-------------------------------------------------------------------------------
-- Title: MSBT Options Controls
-- Author: Mikord
-------------------------------------------------------------------------------

-- Create module and set its name.
local module = {}
local moduleName = "Controls"
MSBTOptions[moduleName] = module


-------------------------------------------------------------------------------
-- Private variables.
-------------------------------------------------------------------------------

-- Prevent tainting global _.
local _

-- Backdrop table to be reused for sliders.
local sliderBackdrop

-- Emphasis shown when a listbox entry is moused over.
local emphasizeFrame

-- Listbox used for dropdowns.
local dropdownListboxFrame

-- Used for correctly calculating string widths.
local calcFontString


-------------------------------------------------------------------------------
-- Listbox functions.
-------------------------------------------------------------------------------

-- ****************************************************************************
-- Shows the highlight frame over the passed line.
-- ****************************************************************************
local function Listbox_ShowHighlight(this, line)
	local highlight = this.highlightFrame
	highlight:ClearAllPoints()
	highlight:SetParent(line)
	highlight:SetPoint("TOPLEFT")
	highlight:SetPoint("BOTTOMRIGHT")
	highlight:Show()

	if (emphasizeFrame:GetParent() == line) then emphasizeFrame:Hide() end
end


-- ****************************************************************************
-- Shows or hides the scroll bar and resizes the display area as necessary.
-- ****************************************************************************
local function Listbox_HandleScrollbar(this)
	-- Show or hide the scroll bar if there are more items than will fit on the page.
	local display = this.displayFrame
	local slider = this.sliderFrame
	if (#this.items <= #this.lines) then
		slider:Hide()
		display:SetPoint("BOTTOMRIGHT")
	else
		display:SetPoint("BOTTOMRIGHT", display:GetParent(), "BOTTOMRIGHT", -16, 0)
		slider:Show()
	end
end


-- ****************************************************************************
-- Returns whether the listbox is fully configured.
-- ****************************************************************************
local function Listbox_IsConfigured(this)
	return this.configured and this.lineHandler and this.displayHandler
end


-- ****************************************************************************
-- Returns the current offset.
-- ****************************************************************************
local function Listbox_GetOffset(this)
	return this.sliderFrame:GetValue()
end


-- ****************************************************************************
-- Returns the current offset.
-- ****************************************************************************
local function Listbox_SetOffset(this, offset)
	this.sliderFrame:SetValue(offset)
end


-- ****************************************************************************
-- Called when the listbox needs to be refreshed.
-- ****************************************************************************
local function Listbox_Refresh(this)
	-- Don't do anything if the listbox isn't configured.
	if (not Listbox_IsConfigured(this)) then return end

	-- Handle scroll bar showing / resizing.
	Listbox_HandleScrollbar(this)

	-- Hide the highlight.
	this.highlightFrame:Hide()

	-- Show or hide the correct lines depending on how many items there are and
	-- apply a highlight to the selected item.
	local selectedItem = this.selectedItem
	local isSelected
	for lineNum, line in ipairs(this.lines) do
		if (lineNum > #this.items) then
			line:Hide()
		else
			line.itemNumber = lineNum + Listbox_GetOffset(this)
			line:Show()

			-- Move the highlight to the selected line and show it.
			if (selectedItem == line.itemNumber) then
				Listbox_ShowHighlight(this, line)
		isSelected = true
			else
				isSelected = false
			end

			if (this.displayHandler) then this:displayHandler(line, this.items[line.itemNumber], isSelected) end
		end
	end
end


-- ****************************************************************************
-- Called when the listbox is scrolled up.
-- ****************************************************************************
local function Listbox_ScrollUp(this)
	local slider = this.sliderFrame
	slider:SetValue(slider:GetValue() - slider:GetValueStep())
end


-- ****************************************************************************
-- Called when the listbox is scrolled down.
-- ****************************************************************************
local function Listbox_ScrollDown(this)
	local slider = this.sliderFrame
	slider:SetValue(slider:GetValue() + slider:GetValueStep())
end


-- ****************************************************************************
-- Called when one of the lines in the listbox is clicked.
-- ****************************************************************************
local function Listbox_OnClickLine(this)
	local listbox = this:GetParent():GetParent()
	listbox.selectedItem = this.lineNumber + Listbox_GetOffset(listbox)

	Listbox_ShowHighlight(listbox, this)

	if (listbox.clickHandler) then listbox:clickHandler(this, listbox.items[listbox.selectedItem]) end
end


-- ****************************************************************************
-- Called when the mouse enters a line.
-- ****************************************************************************
local function Listbox_OnEnterLine(this)
	local listbox = this:GetParent():GetParent()
	if (this.itemNumber ~= listbox.selectedItem) then
		emphasizeFrame:ClearAllPoints()
		emphasizeFrame:SetParent(this)
		emphasizeFrame:SetPoint("TOPLEFT")
		emphasizeFrame:SetPoint("BOTTOMRIGHT")
		emphasizeFrame:Show()
	end

	if (this.tooltip) then
		GameTooltip:SetOwner(this, this.tooltipAnchor or "ANCHOR_RIGHT")
		GameTooltip:SetText(this.tooltip, nil, nil, nil, nil, 1)
	end
end


-- ****************************************************************************
-- Called when the mouse leaves a line.
-- ****************************************************************************
local function Listbox_OnLeaveLine(this)
	emphasizeFrame:Hide()
	GameTooltip:Hide()
end


-- ****************************************************************************
-- Called when the scroll up button is pressed.
-- ****************************************************************************
local function Listbox_OnClickUp(this)
	local listbox = this:GetParent():GetParent()
	Listbox_ScrollUp(listbox)
	PlaySound(826)
end


-- ****************************************************************************
-- Called when the scroll down button is pressed.
-- ****************************************************************************
local function Listbox_OnClickDown(this)
	local listbox = this:GetParent():GetParent()
	Listbox_ScrollDown(listbox)
	PlaySound(827)
end


-- ****************************************************************************
-- Called when the mouse wheel is scrolled in the display frame.
-- ****************************************************************************
local function Listbox_OnMouseWheel(this, delta)
	local listbox = this:GetParent()
	if (delta < 0) then
		Listbox_ScrollDown(listbox)
	elseif (delta > 0) then
		Listbox_ScrollUp(listbox)
	end
end


-- ****************************************************************************
-- Called when the scroll bar slider is changed.
-- ****************************************************************************
local function Listbox_OnValueChanged(this, value)
	Listbox_Refresh(this:GetParent())
end


-- ****************************************************************************
-- Creates a new line using the register create line handler.
-- ****************************************************************************
local function Listbox_CreateLine(this)
	-- Get a line from cache if there are any otherwise call the registered line
	-- handler to create a new line.
	local lineCache = this.lineCache
	local line = (#lineCache > 0) and table.remove(lineCache) or this:lineHandler()

	line:SetParent(this.displayFrame)
	line:SetHeight(this.lineHeight)
	line:ClearAllPoints()
	line:SetScript("OnClick", Listbox_OnClickLine)
	line:SetScript("OnEnter", Listbox_OnEnterLine)
	line:SetScript("OnLeave", Listbox_OnLeaveLine)

	local lines = this.lines
	if (#lines == 0) then
		line:SetPoint("TOPLEFT")
		line:SetPoint("TOPRIGHT")
	else
		line:SetPoint("TOPLEFT", lines[#lines], "BOTTOMLEFT")
		line:SetPoint("TOPRIGHT", lines[#lines], "BOTTOMRIGHT")
	end

	lines[#lines+1] = line
	line.lineNumber = #lines
end


-- ****************************************************************************
-- Reconfigures the listbox if it was already configured.
-- ****************************************************************************
local function Listbox_Reconfigure(this, width, height, lineHeight)
	-- Don't allow negative widths.
	if (width < 0) then width = 0 end

	-- Setup container frame.
	this:SetWidth(width)
	this:SetHeight(height)

	-- Setup line calculations.
	this.lineHeight = lineHeight
	this.linesPerPage = math.floor(height / lineHeight)

	-- Resize the line height of existing lines.
	for _, line in ipairs(this.lines) do
		line:SetHeight(this.lineHeight)
	end

	-- Add lines if more will fit on the page and they are needed.
	local lines = this.lines
	if (#this.items > #lines) then
		while (#lines < this.linesPerPage and #this.items > #lines) do
			Listbox_CreateLine(this)
		end
	end

	-- Remove and cache lines that will no longer fit on the page.
	local lineCache = this.lineCache
	for x = this.linesPerPage+1, #lines do
		lines[#lines]:Hide()
		lineCache[#lineCache+1] = table.remove(lines)
	end

	-- Setup slider frame.
	local slider = this.sliderFrame
	slider:Hide()
	slider:SetMinMaxValues(0, math.max(#this.items - #this.lines, 0))
	slider:SetValue(0)

	Listbox_Refresh(this)
end


-- ****************************************************************************
-- Configures the listbox.
-- ****************************************************************************
local function Listbox_Configure(this, width, height, lineHeight)
	-- Don't do anything if required parameters are invalid.
	if (not width or not height or not lineHeight) then return end

	if (Listbox_IsConfigured(this)) then Listbox_Reconfigure(this, width, height, lineHeight) return end

	-- Don't allow negative widths.
	if (width < 0) then width = 0 end

	-- Setup container frame.
	this:SetWidth(width)
	this:SetHeight(height)

	-- Setup slider frame.
	local slider = this.sliderFrame
	slider:SetMinMaxValues(0, 0)
	slider:SetValue(0)

	-- Setup line calculations.
	this.lineHeight = lineHeight
	this.linesPerPage = math.floor(height / lineHeight)

	this.configured = true
end


-- ****************************************************************************
-- Set the function to be called when a new line needs to be created. The
-- called function must return a "Button" frame.
-- ****************************************************************************
local function Listbox_SetCreateLineHandler(this, handler)
	this.lineHandler = handler
end


-- ****************************************************************************
-- Set the function to be called when a line is being displayed.
-- It is passed the line frame to be populated, and the value associated
-- with that line.
-- ****************************************************************************
local function Listbox_SetDisplayHandler(this, handler)
	this.displayHandler = handler
end


-- ****************************************************************************
-- Set the function to be called when a line in the listbox is clicked.
-- It is passed the line frame, and the value associated with that line.
-- ****************************************************************************
local function Listbox_SetClickHandler(this, handler)
	this.clickHandler = handler
end


-- ****************************************************************************
-- Returns the passed item number from the listbox.
-- ****************************************************************************
local function Listbox_GetItem(this, itemNumber)
	return this.items[itemNumber]
end


-- ****************************************************************************
-- Adds the passed item to the listbox.
-- ****************************************************************************
local function Listbox_AddItem(this, key, forceVisible)
	-- Don't do anything if the listbox isn't configured.
	if (not Listbox_IsConfigured(this)) then return end

	-- Add the passed key to the items list.
	local items = this.items
	items[#items + 1] = key

	-- Create a new line if the max number allowed per page hasn't been reached.
	local lines = this.lines
	if (#lines < this.linesPerPage) then
		Listbox_CreateLine(this)
	end

	-- Set the new max offset value.
	local maxOffset = math.max(#items - #lines, 0)
	this.sliderFrame:SetMinMaxValues(0, maxOffset)

	-- Make sure the newly added item is visible if the force flag is set.
	if (forceVisible) then Listbox_SetOffset(this, maxOffset) end

	Listbox_Refresh(this)
end


-- ****************************************************************************
-- Removes the passed item number from the listbox.
-- ****************************************************************************
local function Listbox_RemoveItem(this, itemNumber)
	-- Don't do anything if the listbox isn't configured.
	if (not Listbox_IsConfigured(this)) then return end

	local items = this.items
	table.remove(items, itemNumber)

	-- Set the new max offset value.
	this.sliderFrame:SetMinMaxValues(0, math.max(#items - #this.lines, 0))

	Listbox_Refresh(this)
end


-- ****************************************************************************
-- Returns the number of items in the listbox.
-- ****************************************************************************
local function Listbox_GetNumItems(this)
	return #this.items
end


-- ****************************************************************************
-- Returns the selected item from the listbox.
-- ****************************************************************************
local function Listbox_GetSelectedItem(this)
	if (this.selectedItem ~= 0) then return this.items[this.selectedItem] end
end


-- ****************************************************************************
-- Sets the selected item for the listbox.
-- ****************************************************************************
local function Listbox_SetSelectedItem(this, itemNumber)
	-- Don't do anything if the listbox isn't configured.
	if (not Listbox_IsConfigured(this)) then return end

	this.selectedItem = itemNumber <= #this.items and itemNumber or 0

	-- Highlight the selected line if it's visible.
	local line = this.lines[this.selectedItem - this.sliderFrame:GetValue()]
	if (line) then Listbox_ShowHighlight(this, line) end
end


-- ****************************************************************************
-- Returns the line object from the listbox.
-- ****************************************************************************
local function Listbox_GetLine(this, lineNumber)
	local lines = this.lines
	if (lineNumber <= #lines) then return lines[lineNumber] end
end


-- ****************************************************************************
-- Returns the number of lines in the listbox.
-- ****************************************************************************
local function Listbox_GetNumLines(this)
	return math.min(#this.lines, #this.items)
end


-- ****************************************************************************
-- Clears the listbox contents.
-- ****************************************************************************
local function Listbox_Clear(this)
	-- Don't do anything if the listbox isn't configured.
	if (not Listbox_IsConfigured(this)) then return end

	local items = this.items
	for k, v in ipairs(items) do
		items[k] = nil
	end

	-- Set the new max offset value.
	this.sliderFrame:SetMinMaxValues(0, 0)

	this.selectedItem = 0

	Listbox_Refresh(this)
end


-- ****************************************************************************
-- Disables the listbox.
-- ****************************************************************************
local function Listbox_Disable(this)
	this.displayFrame:EnableMouseWheel(false)
	this.sliderFrame:EnableMouse(false)
	this.upButton:Disable()
	this.downButton:Disable()
end


-- ****************************************************************************
-- Enables the listbox.
-- ****************************************************************************
local function Listbox_Enable(this)
	this.displayFrame:EnableMouseWheel(true)
	this.sliderFrame:EnableMouse(true)
	this.upButton:Enable()
	this.downButton:Enable()
end


-- ****************************************************************************
-- Creates and returns a listbox object ready to be configured.
-- ****************************************************************************
local function CreateListbox(parent)
	-- Create the frame used to emphasize the entry the mouse is over.
	if (not emphasizeFrame) then
		emphasizeFrame = CreateFrame("Frame")

		local texture = emphasizeFrame:CreateTexture(nil, "ARTWORK")
		texture:SetTexture("Interface\\QuestFrame\\UI-QuestLogTitleHighlight")
		texture:SetBlendMode("ADD")
		texture:SetPoint("TOPLEFT", emphasizeFrame, "TOPLEFT")
		texture:SetPoint("BOTTOMRIGHT", emphasizeFrame, "BOTTOMRIGHT")
	end

	-- Create container frame.
	local listbox = CreateFrame("Frame", nil, parent)

	-- Highlight frame.
	local highlight = CreateFrame("Frame")

	local texture = highlight:CreateTexture(nil, "ARTWORK")
	texture:SetTexture("Interface\\QuestFrame\\UI-QuestTitleHighlight")
	texture:SetBlendMode("ADD")
	texture:SetPoint("TOPLEFT", highlight, "TOPLEFT")
	texture:SetPoint("BOTTOMRIGHT", highlight, "BOTTOMRIGHT")

	-- Create display area.
	local display = CreateFrame("Frame", nil, listbox)
	display:SetPoint("TOPLEFT", listbox, "TOPLEFT")
	display:SetPoint("BOTTOMRIGHT", listbox, "BOTTOMRIGHT")


	-- Create slider to track the position.
	local slider = CreateFrame("Slider", nil, listbox)
	slider:Hide()
	slider:SetWidth(16)
	slider:SetPoint("TOPRIGHT", listbox, "TOPRIGHT", 0, -16)
	slider:SetPoint("BOTTOMRIGHT", listbox, "BOTTOMRIGHT", 0, 16)
	slider:SetThumbTexture("Interface\\Buttons\\UI-ScrollBar-Knob")
	slider:SetValueStep(1)
	slider:SetObeyStepOnDrag(true)
	slider:SetScript("OnValueChanged", Listbox_OnValueChanged)

	-- Up button.
	local upButton = CreateFrame("Button", nil, slider, "UIPanelScrollUpButtonTemplate")
	upButton:SetPoint("BOTTOM", slider, "TOP")
	upButton:SetScript("OnClick", Listbox_OnClickUp)

	-- Down button.
	local downButton = CreateFrame("Button", nil, slider, "UIPanelScrollDownButtonTemplate")
	downButton:SetPoint("TOP", slider, "BOTTOM")
	downButton:SetScript("OnClick", Listbox_OnClickDown)


	-- Make it work with the mouse wheel.
	display:EnableMouseWheel(true)
	display:SetScript("OnMouseWheel", Listbox_OnMouseWheel)


	-- Extension functions.
	listbox.Configure				= Listbox_Configure
	listbox.SetCreateLineHandler	= Listbox_SetCreateLineHandler
	listbox.SetDisplayHandler		= Listbox_SetDisplayHandler
	listbox.SetClickHandler		= Listbox_SetClickHandler
	listbox.GetOffset				= Listbox_GetOffset
	listbox.SetOffset				= Listbox_SetOffset
	listbox.GetItem				= Listbox_GetItem
	listbox.AddItem				= Listbox_AddItem
	listbox.RemoveItem				= Listbox_RemoveItem
	listbox.GetNumItems			= Listbox_GetNumItems
	listbox.GetSelectedItem		= Listbox_GetSelectedItem
	listbox.SetSelectedItem		= Listbox_SetSelectedItem
	listbox.GetLine				= Listbox_GetLine
	listbox.GetNumLines			= Listbox_GetNumLines
	listbox.Refresh				= Listbox_Refresh
	listbox.Clear					= Listbox_Clear
	listbox.Disable				= Listbox_Disable
	listbox.Enable					= Listbox_Enable

	-- Track internal values.
	listbox.displayFrame = display
	listbox.sliderFrame = slider
	listbox.upButton = upButton
	listbox.downButton = downButton
	listbox.highlightFrame = highlight
	listbox.items = {}
	listbox.lines = {}
	listbox.lineCache = {}
	listbox.selectedItem = 0
	return listbox
end


-------------------------------------------------------------------------------
-- Checkbox functions.
-------------------------------------------------------------------------------

-- ****************************************************************************
-- Called when the internal checkbutton is clicked.
-- ****************************************************************************
local function Checkbox_OnClick(this)
	local isChecked = this:GetChecked() and true or false
	if (isChecked) then PlaySound(856) else PlaySound(857) end

	local checkbox = this:GetParent()
	if (checkbox.clickHandler) then checkbox:clickHandler(isChecked) end
end


-- ****************************************************************************
-- Called when the mouse enters the internal checkbutton.
-- ****************************************************************************
local function Checkbox_OnEnter(this)
	if (this.tooltip) then
		GameTooltip:SetOwner(this, this.tooltipAnchor or "ANCHOR_RIGHT")
		GameTooltip:SetText(this.tooltip, nil, nil, nil, nil, 1)
	end
end


-- ****************************************************************************
-- Called when the mouse leaves the internal checkbutton.
-- ****************************************************************************
local function Checkbox_OnLeave(this)
	GameTooltip:Hide()
end


-- ****************************************************************************
-- Sets the label for the checkbox.
-- ****************************************************************************
local function Checkbox_SetLabel(this, label)
	local fontString = this.fontString
	fontString:SetText(label or "")
	calcFontString:SetText(label or "")
	local width = this.checkFrame:GetWidth() + calcFontString:GetStringWidth() + 2
	this:SetWidth(math.ceil(width))
end


-- ****************************************************************************
-- Sets the tooltip for the checkbox.
-- ****************************************************************************
local function Checkbox_SetTooltip(this, tooltip)
	this.checkFrame.tooltip = tooltip
end


-- ****************************************************************************
-- Configures the checkbox.
-- ****************************************************************************
local function Checkbox_Configure(this, size, label, tooltip)
	-- Don't do anything if required parameters are invalid.
	if (not size) then return end

	-- Setup the container frame.
	this:SetHeight(size)

	-- Setup the checkbox dimensions.
	local check = this.checkFrame
	check:SetWidth(size)
	check:SetHeight(size)

	-- Setup the label and tooltip.
	Checkbox_SetLabel(this, label)
	Checkbox_SetTooltip(this, tooltip)

	this.configured = true
end


-- ****************************************************************************
-- Sets the function to be called when the checkbox is clicked.
-- It is passed the checkbox and whether or not it's checked.
-- ****************************************************************************
local function Checkbox_SetClickHandler(this, handler)
	this.clickHandler = handler
end


-- ****************************************************************************
-- Returns whether or not the checkbox is checked.
-- ****************************************************************************
local function Checkbox_GetChecked(this)
	return this.checkFrame:GetChecked() and true or false
end


-- ****************************************************************************
-- Sets the checked state.
-- ****************************************************************************
local function Checkbox_SetChecked(this, isChecked)
	this.checkFrame:SetChecked(isChecked)
end


-- ****************************************************************************
-- Disables the checkbox.
-- ****************************************************************************
local function Checkbox_Disable(this)
	this.checkFrame:Disable()
	this.fontString:SetTextColor(0.5, 0.5, 0.5)
end


-- ****************************************************************************
-- Enables the checkbox.
-- ****************************************************************************
local function Checkbox_Enable(this)
	this.checkFrame:Enable()
	this.fontString:SetTextColor(NORMAL_FONT_COLOR.r, NORMAL_FONT_COLOR.g, NORMAL_FONT_COLOR.b)
end


-- ****************************************************************************
-- Creates and returns a checkbox object ready to be configured.
-- ****************************************************************************
local function CreateCheckbox(parent)
	-- XXX Hack to work around apparent WoW API bug not returning correct string width.
	if (not calcFontString) then
		calcFontString = UIParent:CreateFontString(nil, "ARTWORK", "GameFontNormalSmall")
	end

	-- Create container frame.
	local checkbox = CreateFrame("Frame", nil, parent)

	-- Create check button.
	local checkbutton = CreateFrame("CheckButton", nil, checkbox)
	checkbutton:SetPoint("TOPLEFT")
	checkbutton:SetNormalTexture("Interface\\Buttons\\UI-CheckBox-Up")
	checkbutton:SetPushedTexture("Interface\\Buttons\\UI-CheckBox-Down")
	checkbutton:SetHighlightTexture("Interface\\Buttons\\UI-CheckBox-Highlight")
	checkbutton:SetDisabledCheckedTexture("Interface\\Buttons\\UI-CheckBox-Check-Disabled")
	checkbutton:SetCheckedTexture("Interface\\Buttons\\UI-CheckBox-Check")
	checkbutton:SetScript("OnClick", Checkbox_OnClick)
	checkbutton:SetScript("OnEnter", Checkbox_OnEnter)
	checkbutton:SetScript("OnLeave", Checkbox_OnLeave)

	-- Label.
	local fontString = checkbox:CreateFontString(nil, "OVERLAY", "GameFontNormalSmall")
	fontString:SetPoint("LEFT", checkbutton, "RIGHT", 2, 0)
	fontString:SetPoint("RIGHT", checkbox, "RIGHT", 0, 0)
	fontString:SetJustifyH("LEFT")


	-- Extension functions.
	checkbox.Configure			= Checkbox_Configure
	checkbox.SetLabel			= Checkbox_SetLabel
	checkbox.SetTooltip		= Checkbox_SetTooltip
	checkbox.SetClickHandler	= Checkbox_SetClickHandler
	checkbox.GetChecked		= Checkbox_GetChecked
	checkbox.SetChecked		= Checkbox_SetChecked
	checkbox.Disable			= Checkbox_Disable
	checkbox.Enable			= Checkbox_Enable

	-- Track internal values.
	checkbox.checkFrame = checkbutton
	checkbox.fontString = fontString
	return checkbox
end



-------------------------------------------------------------------------------
-- Button functions.
-------------------------------------------------------------------------------

-- ****************************************************************************
-- Called when the button is clicked.
-- ****************************************************************************
local function Button_OnClick(this)
	PlaySound(856)
	if (this.clickHandler) then this:clickHandler() end
end


-- ****************************************************************************
-- Called when the mouse enters the button.
-- ****************************************************************************
local function Button_OnEnter(this)
	if (this.tooltip) then
		GameTooltip:SetOwner(this, "ANCHOR_RIGHT")
		GameTooltip:SetText(this.tooltip, nil, nil, nil, nil, 1)
	end
end


-- ****************************************************************************
-- Called when the mouse leaves the button.
-- ****************************************************************************
local function Button_OnLeave(this)
	GameTooltip:Hide()
end


-- ****************************************************************************
-- Sets the tooltip for the button.
-- ****************************************************************************
local function Button_SetTooltip(this, tooltip)
	this.tooltip = tooltip
end


-- ****************************************************************************
-- Sets the function to be called when the button is clicked.
-- ****************************************************************************
local function Button_SetClickHandler(this, handler)
	this.clickHandler = handler
end



-- ****************************************************************************
-- Creates and returns a generic button object. Only used internally.
-- ****************************************************************************
local function CreateButton(parent)
	-- Create button frame.
	local button = CreateFrame("Button", nil, parent)
	button:SetScript("OnClick", Button_OnClick)
	button:SetScript("OnEnter", Button_OnEnter)
	button:SetScript("OnLeave", Button_OnLeave)

	-- Extension functions.
	button.SetClickHandler	= Button_SetClickHandler
	button.SetTooltip	= Button_SetTooltip

	return button
end


-------------------------------------------------------------------------------
-- OptionButton functions.
-------------------------------------------------------------------------------

-- ****************************************************************************
-- Set the label for the option button.
-- ****************************************************************************
local function OptionButton_SetLabel(this, label)
	this:SetText(label or "")
	this:SetWidth(this:GetFontString():GetStringWidth() + 50)
end


-- ****************************************************************************
-- Configures the option button.
-- ****************************************************************************
local function OptionButton_Configure(this, height, label, tooltip)
	this:SetHeight(height)
	OptionButton_SetLabel(this, label)
	Button_SetTooltip(this, tooltip)
end


-- ****************************************************************************
-- Creates and returns a push button object ready to be configured.
-- ****************************************************************************
local function CreateOptionButton(parent)
	-- Create generic button.
	local button = CreateButton(parent)
	local fontString = button:CreateFontString(nil, "OVERLAY")
	fontString:SetPoint("CENTER")
	button:SetFontString(fontString)
	button:SetNormalFontObject(GameFontNormalSmall)
	button:SetHighlightFontObject(GameFontHighlightSmall)
	button:SetDisabledFontObject(GameFontDisableSmall)
	button:SetNormalTexture("Interface\\Buttons\\UI-Panel-Button-Up")
	button:SetPushedTexture("Interface\\Buttons\\UI-Panel-Button-Down")
	button:SetDisabledTexture("Interface\\Buttons\\UI-Panel-Button-Disabled")
	button:SetHighlightTexture("Interface\\Buttons\\UI-Panel-Button-Highlight")
	button:GetNormalTexture():SetTexCoord(0, 0.625, 0, 0.6875)
	button:GetPushedTexture():SetTexCoord(0, 0.625, 0, 0.6875)
	button:GetDisabledTexture():SetTexCoord(0, 0.625, 0, 0.6875)
	button:GetHighlightTexture():SetTexCoord(0, 0.625, 0, 0.6875)


	-- Extension functions.
	button.SetLabel			= OptionButton_SetLabel
	button.Configure		= OptionButton_Configure

	return button
end


-------------------------------------------------------------------------------
-- IconButton functions.
-------------------------------------------------------------------------------

-- ****************************************************************************
-- Creates and returns an icon button object ready to be configured.
-- ****************************************************************************
local function CreateIconButton(parent, buttonType)
	-- Create generic button.
	local button = CreateButton(parent)
	button:SetWidth(24)
	button:SetHeight(24)
	button:SetNormalTexture("Interface\\Addons\\MSBTOptions\\Artwork\\" .. buttonType .. "Icon")
	button:SetDisabledTexture("Interface\\Addons\\MSBTOptions\\Artwork\\" .. buttonType .. "IconDisable")
	button:SetHighlightTexture("Interface\\Addons\\MSBTOptions\\Artwork\\" .. buttonType .. "IconHighlight")

	return button
end


-------------------------------------------------------------------------------
-- Slider functions.
-------------------------------------------------------------------------------

-- ****************************************************************************
-- Called when the value of the slider changes.
-- ****************************************************************************
local function Slider_OnValueChanged(this, value)
	local slider = this:GetParent()
	if (slider.labelText ~= "") then
		slider.labelFontString:SetText(slider.labelText .. ": " .. value)
	else
		slider.labelFontString:SetText(value)
	end
	if (slider.valueChangedHandler) then slider:valueChangedHandler(value) end
end


-- ****************************************************************************
-- Called when the mouse enters the slider.
-- ****************************************************************************
local function Slider_OnEnter(this)
	if (this.tooltip) then
		GameTooltip:SetOwner(this, this.tooltipAnchor or "ANCHOR_RIGHT")
		GameTooltip:SetText(this.tooltip, nil, nil, nil, nil, 1)
	end
end


-- ****************************************************************************
-- Called when the mouse leaves the slider.
-- ****************************************************************************
local function Slider_OnLeave(this)
	GameTooltip:Hide()
end


-- ****************************************************************************
-- Sets the label for the slider.
-- ****************************************************************************
local function Slider_SetLabel(this, label)
	this.labelText = label or ""
	if (this.labelText ~= "") then
		this.labelFontString:SetText(this.labelText .. ": " .. this:GetValue())
	else
		this.labelFontString:SetText(this:GetValue())
	end
end


-- ****************************************************************************
-- Sets the tooltip for the slider.
-- ****************************************************************************
local function Slider_SetTooltip(this, tooltip)
	this.sliderFrame.tooltip = tooltip
end


-- ****************************************************************************
-- Configures the slider.
-- ****************************************************************************
local function Slider_Configure(this, width, label, tooltip)
	this:SetWidth(width)
	Slider_SetLabel(this, label)
	Slider_SetTooltip(this, tooltip)
end


-- ****************************************************************************
-- Sets the function to be called when the value of the slider is changed.
-- It is passed the slider and the new value.
-- ****************************************************************************
local function Slider_SetValueChangedHandler(this, handler)
	this.valueChangedHandler = handler
end


-- ****************************************************************************
-- Sets the minimum and maximum values for the slider.
-- ****************************************************************************
local function Slider_SetMinMaxValues(this, minValue, maxValue)
	this.sliderFrame:SetMinMaxValues(minValue, maxValue)
end


-- ****************************************************************************
-- Sets how far the slider moves with each "tick."
-- ****************************************************************************
local function Slider_SetValueStep(this, value)
	this.sliderFrame:SetValueStep(value)
end


-- ****************************************************************************
-- Sets the current value of the slider.
-- ****************************************************************************
local function Slider_GetValue(this)
	return this.sliderFrame:GetValue()
end


-- ****************************************************************************
-- Sets the current value of the slider.
-- ****************************************************************************
local function Slider_SetValue(this, value)
	this.sliderFrame:SetValue(value)
end


-- ****************************************************************************
-- Disables the slider.
-- ****************************************************************************
local function Slider_Disable(this)
	this.sliderFrame:EnableMouse(false)
	this.labelFontString:SetTextColor(0.5, 0.5, 0.5)
end


-- ****************************************************************************
-- Enables the slider.
-- ****************************************************************************
local function Slider_Enable(this)
	this.sliderFrame:EnableMouse(true)
	this.labelFontString:SetTextColor(NORMAL_FONT_COLOR.r, NORMAL_FONT_COLOR.g, NORMAL_FONT_COLOR.b)
end


-- ****************************************************************************
-- Creates and returns a slider object ready to be configured.
-- ****************************************************************************
local function CreateSlider(parent)
	-- Create the backdrop table if it hasn't already been so it can be reused.
	if (not sliderBackdrop) then
		sliderBackdrop = {
			bgFile = "Interface\\Buttons\\UI-SliderBar-Background",
			edgeFile = "Interface\\Buttons\\UI-SliderBar-Border",
			tile = true, tileSize = 8, edgeSize = 8,
			insets = {left=3, right=3, top=6, bottom=6},
		}
	end

	-- Create container frame.
	local slider = CreateFrame("Frame", nil, parent)
	slider:SetHeight(30)

	-- Create slider.
	local sliderFrame = CreateFrame("Slider", nil, slider, BackdropTemplateMixin and "BackdropTemplate")
	sliderFrame:SetOrientation("HORIZONTAL")
	sliderFrame:SetThumbTexture("Interface\\Buttons\\UI-SliderBar-Button-Horizontal")
	sliderFrame:SetPoint("LEFT")
	sliderFrame:SetPoint("RIGHT")
	sliderFrame:SetHeight(16)
	sliderFrame:SetBackdrop(sliderBackdrop)
	sliderFrame:SetObeyStepOnDrag(true)
	sliderFrame:SetScript("OnValueChanged", Slider_OnValueChanged)
	sliderFrame:SetScript("OnEnter", Slider_OnEnter)
	sliderFrame:SetScript("OnLeave", Slider_OnLeave)


	-- Label.
	local label = slider:CreateFontString(nil, "OVERLAY", "GameFontNormalSmall")
	label:SetPoint("BOTTOM", sliderFrame, "TOP", 0, 0)

	-- Extension functions.
	slider.Configure				= Slider_Configure
	slider.SetLabel				= Slider_SetLabel
	slider.SetTooltip				= Slider_SetTooltip
	slider.SetValueChangedHandler	= Slider_SetValueChangedHandler
	slider.SetMinMaxValues			= Slider_SetMinMaxValues
	slider.SetValueStep			= Slider_SetValueStep
	slider.GetValue				= Slider_GetValue
	slider.SetValue				= Slider_SetValue
	slider.Enable					= Slider_Enable
	slider.Disable					= Slider_Disable


	-- Track internal values.
	slider.sliderFrame = sliderFrame
	slider.labelFontString = label
	slider.labelText = ""
	return slider
end


-------------------------------------------------------------------------------
-- Dropdown functions.
-------------------------------------------------------------------------------

-- ****************************************************************************
-- Hides the dropdown listbox frame that holds the selections.
-- ****************************************************************************
local function Dropdown_HideSelections(this)
	if (dropdownListboxFrame:IsShown() and dropdownListboxFrame.dropdown == this) then
		dropdownListboxFrame:Hide()
	end
end

-- ****************************************************************************
-- Called when the mouse enters the dropdown.
-- ****************************************************************************
local function Dropdown_OnEnter(this)
	if (this.tooltip) then
		GameTooltip:SetOwner(this, this.tooltipAnchor or "ANCHOR_RIGHT")
		GameTooltip:SetText(this.tooltip, nil, nil, nil, nil, 1)
	end
end


-- ****************************************************************************
-- Called when the mouse leaves the dropdown.
-- ****************************************************************************
local function Dropdown_OnLeave(this)
	GameTooltip:Hide()
end


-- ****************************************************************************
-- Called when the dropdown is hidden.
-- ****************************************************************************
local function Dropdown_OnHide(this)
	Dropdown_HideSelections(this)
end


-- ****************************************************************************
-- Called when the button for the dropdown is pressed.
-- ****************************************************************************
local function Dropdown_OnClick(this)
	-- Close the listbox and exit if it's already open for the dropdown.
	local dropdown = this:GetParent()
	if (dropdownListboxFrame:IsShown() and dropdownListboxFrame.dropdown == dropdown) then
		dropdownListboxFrame:Hide()
		return
	end

	-- Resize and move the dropdown listbox frame for the clicked dropdown.
	local height = #dropdown.items * 20
	local listboxHeight = dropdown.listboxHeight or 140
	local listboxWidth = dropdown.listboxWidth or dropdown:GetWidth() + 20
	height = math.max(math.min(height, listboxHeight), 20)
	dropdownListboxFrame:SetParent(dropdown:GetParent())
	dropdownListboxFrame:SetHeight(height + 24)
	dropdownListboxFrame:SetWidth(listboxWidth)
	dropdownListboxFrame:ClearAllPoints()
	dropdownListboxFrame:SetPoint("TOPLEFT", dropdown, "BOTTOMLEFT")
	dropdownListboxFrame.dropdown = dropdown

	-- Setup the listbox.
	local listbox = dropdownListboxFrame.listbox
	Listbox_Clear(listbox)
	listbox:SetPoint("TOPLEFT", dropdownListboxFrame, "TOPLEFT", 8, -12)
	listbox:SetPoint("BOTTOMRIGHT", dropdownListboxFrame, "BOTTOMRIGHT", -12, 12)
	Listbox_Configure(listbox, 0, height, 20)
	for itemNum in ipairs(dropdown.items) do
		Listbox_AddItem(listbox, itemNum)
	end
	Listbox_SetSelectedItem(listbox, dropdown.selectedItem)
	Listbox_SetOffset(listbox, dropdown.selectedItem - 1)

	dropdownListboxFrame:Show()
	dropdownListboxFrame:Raise()
end


-- ****************************************************************************
-- Called by listbox to create a line.
-- ****************************************************************************
local function Dropdown_CreateLine(this)
	local frame = CreateFrame("Button", nil, this)

	local fontString = frame:CreateFontString(nil, "OVERLAY", "GameFontNormalSmall")
	fontString:SetPoint("LEFT", frame, "LEFT")
	fontString:SetPoint("RIGHT", frame, "RIGHT")

	frame.fontString = fontString
	return frame
end


-- ****************************************************************************
-- Called by listbox to display a line.
-- ****************************************************************************
local function Dropdown_DisplayLine(this, line, key, isSelected)
	line.fontString:SetText(dropdownListboxFrame.dropdown.items[key])
	local color = isSelected and HIGHLIGHT_FONT_COLOR or NORMAL_FONT_COLOR
	line.fontString:SetTextColor(color.r, color.g, color.b)
end


-- ****************************************************************************
-- Called when a line is clicked.
-- ****************************************************************************
local function Dropdown_OnClickLine(this, line, value)
	local dropdown = dropdownListboxFrame.dropdown
	dropdown.selectedFontString:SetText(dropdown.items[value])
	dropdown.selectedItem = value
	dropdownListboxFrame:Hide()

	-- Call the registered change handler for the dropdown.
	if (dropdown.changeHandler) then dropdown:changeHandler(dropdown.itemIDs[value]) end
end


-- ****************************************************************************
-- Sets the label for the dropdown.
-- ****************************************************************************
local function Dropdown_SetLabel(this, label)
	this.labelFontString:SetText(label or "")
end


-- ****************************************************************************
-- Sets the tooltip for the dropdown.
-- ****************************************************************************
local function Dropdown_SetTooltip(this, tooltip)
	this.tooltip = tooltip
end


-- ****************************************************************************
-- Configures the dropdown.
-- ****************************************************************************
local function Dropdown_Configure(this, width, label, tooltip)
	-- Don't do anything if required parameters are invalid.
	if (not width) then return end

	-- Set the width of the dropdown and the max height of the listbox is shown.
	this:SetWidth(width)

	Dropdown_SetLabel(this, label)
	Dropdown_SetTooltip(this, tooltip)
end


-- ****************************************************************************
-- Sets the max height the listbox frame can be for the dropdown.
-- ****************************************************************************
local function Dropdown_SetListboxHeight(this, height)
	this.listboxHeight = height
end

-- ****************************************************************************
-- Sets the width of the listbox frame for the dropdown.
-- ****************************************************************************
local function Dropdown_SetListboxWidth(this, width)
	this.listboxWidth = width
end


-- ****************************************************************************
-- Sets the function to be called when one of the dropdown's options is
-- selected. It is passed the ID for the selected item.
-- ****************************************************************************
local function Dropdown_SetChangeHandler(this, handler)
	this.changeHandler = handler
end


-- ****************************************************************************
-- Adds the passed text and id to the dropdown.
-- ****************************************************************************
local function Dropdown_AddItem(this, text, id)
	this.items[#this.items+1] = text
	this.itemIDs[#this.items] = id
end


-- ****************************************************************************
-- Remove the passed item id from the dropdown.
-- ****************************************************************************
local function Dropdown_RemoveItem(this, id)
	for itemNum, itemID in ipairs(this.itemIDs) do
		if (itemID == id) then
			-- Hide dropdown if it is shown.
			Dropdown_HideSelections(this)

			-- Clear the selected item if it's the item being removed.
			if (itemNum == this.selectedItem) then
				this.selectedItem = 0
	this.selectedFontString:SetText("")
			end

			table.remove(this.items, itemNum)
			table.remove(this.itemIDs, itemNum)
			return
		end
	end
end


-- ****************************************************************************
-- Clears the dropdown.
-- ****************************************************************************
local function Dropdown_Clear(this)
	local items = this.items
	for k, v in ipairs(items) do
		items[k] = nil
	end

	local itemIDs = this.itemIDs
	for k, v in ipairs(itemIDs) do
		itemIDs[k] = nil
	end

	this.selectedFontString:SetText(nil)
end


-- ****************************************************************************
-- Gets the selected text from the dropdown.
-- ****************************************************************************
local function Dropdown_GetSelectedText(this)
	return this.selectedFontString:GetText()
end


-- ****************************************************************************
-- Gets the selected id from the dropdown.
-- ****************************************************************************
local function Dropdown_GetSelectedID(this)
	if (this.selectedItem) then return this.itemIDs[this.selectedItem] end
end


-- ****************************************************************************
-- Sets the selected item for the listbox.
-- ****************************************************************************
local function Dropdown_SetSelectedID(this, id)
	for itemNum, itemID in ipairs(this.itemIDs) do
		if (itemID == id) then
			this.selectedFontString:SetText(this.items[itemNum])
			this.selectedItem = itemNum
			return
		end
	end
end


-- ****************************************************************************
-- Sorts the contents of the dropdown.
-- ****************************************************************************
local function Dropdown_Sort(this)
	local selectedID = Dropdown_GetSelectedID(this)

	-- Sort the dropdown items and associated IDs using an insertion sort.
	local items = this.items
	local itemIDs = this.itemIDs
	local tempItem, tempID, j
	for i = 2, #items do
		tempItem = items[i]
		tempID = itemIDs[i]
		j = i - 1
		while (j > 0 and items[j] > tempItem) do
			items[j + 1] = items[j]
			itemIDs[j + 1] = itemIDs[j]
			j = j - 1
		end
		items[j + 1] = tempItem
		itemIDs[j + 1] = tempID
	end

	Dropdown_SetSelectedID(this, selectedID)
end


-- ****************************************************************************
-- Disables the dropdown.
-- ****************************************************************************
local function Dropdown_Disable(this)
	Dropdown_HideSelections(this)
	this.buttonFrame:Disable()
	this:EnableMouse(false)
	this.labelFontString:SetTextColor(0.5, 0.5, 0.5)
	this.selectedFontString:SetTextColor(0.5, 0.5, 0.5)
end


-- ****************************************************************************
-- Enables the dropdown.
-- ****************************************************************************
local function Dropdown_Enable(this)
	this:EnableMouse(true)
	this.buttonFrame:Enable()
	this.labelFontString:SetTextColor(NORMAL_FONT_COLOR.r, NORMAL_FONT_COLOR.g, NORMAL_FONT_COLOR.b)
	this.selectedFontString:SetTextColor(HIGHLIGHT_FONT_COLOR.r, HIGHLIGHT_FONT_COLOR.g, HIGHLIGHT_FONT_COLOR.b)
end


-- ****************************************************************************
-- Creates the listbox frame that dropdowns use.
-- ****************************************************************************
local function Dropdown_CreateListboxFrame(parent)
	dropdownListboxFrame = CreateFrame("Frame", nil, parent, BackdropTemplateMixin and "BackdropTemplate")
	dropdownListboxFrame:EnableMouse(true)
	dropdownListboxFrame:SetToplevel(true)
	dropdownListboxFrame:SetFrameStrata("FULLSCREEN_DIALOG")
	dropdownListboxFrame:SetBackdrop{
		bgFile = "Interface\\Addons\\MSBTOptions\\Artwork\\PlainBackdrop",
		edgeFile = "Interface\\Tooltips\\UI-Tooltip-Border",
		insets = {left = 6, right = 6, top = 6, bottom = 6},
	}
	dropdownListboxFrame:Hide()

	local listbox = CreateListbox(dropdownListboxFrame)
	listbox:SetToplevel(true)
	listbox:SetFrameStrata("FULLSCREEN_DIALOG")
	listbox:SetCreateLineHandler(Dropdown_CreateLine)
	listbox:SetDisplayHandler(Dropdown_DisplayLine)
	listbox:SetClickHandler(Dropdown_OnClickLine)

	dropdownListboxFrame.listbox = listbox
end


-- ****************************************************************************
-- Creates and returns a dropdown object ready to be configured.
-- ****************************************************************************
local function CreateDropdown(parent)
	-- Create dropdown listbox if it hasn't already been.
	if (not dropdownListboxFrame) then Dropdown_CreateListboxFrame(parent) end


	-- Create container frame.
	local dropdown = CreateFrame("Frame", nil, parent)
	dropdown:SetHeight(38)
	dropdown:EnableMouse(true)
	dropdown:SetScript("OnEnter", Dropdown_OnEnter)
	dropdown:SetScript("OnLeave", Dropdown_OnLeave)
	dropdown:SetScript("OnHide", Dropdown_OnHide)


	-- Left border.
	local left = dropdown:CreateTexture(nil, "BACKGROUND")
	left:SetTexture("Interface\\Glues\\CharacterCreate\\CharacterCreate-LabelFrame")
	left:SetWidth(9)
	left:SetHeight(25)
	left:SetPoint("BOTTOMLEFT")
	left:SetTexCoord(0.125, 0.1953125, 0.28125, 0.671875)

	-- Right border.
	local right = dropdown:CreateTexture(nil, "BACKGROUND")
	right:SetTexture("Interface\\Glues\\CharacterCreate\\CharacterCreate-LabelFrame")
	right:SetWidth(9)
	right:SetHeight(25)
	right:SetPoint("BOTTOMRIGHT")
	right:SetTexCoord(0.7890625, 0.859375, 0.28125, 0.671875)

	-- Middle border.
	local middle = dropdown:CreateTexture(nil, "BACKGROUND")
	middle:SetTexture("Interface\\Glues\\CharacterCreate\\CharacterCreate-LabelFrame")
	middle:SetWidth(76)
	middle:SetHeight(25)
	middle:SetPoint("LEFT", left, "RIGHT", 0, 0)
	middle:SetPoint("RIGHT", right, "LEFT", 0, 0)
	middle:SetTexCoord(0.1953125, 0.7890625, 0.28125, 0.671875)

	-- Label.
	local label = dropdown:CreateFontString(nil, "OVERLAY", "GameFontNormalSmall")
	label:SetPoint("BOTTOMLEFT", left, "TOPLEFT", 2, 2)


	-- Dropdown button.
	local button = CreateFrame("Button", nil, dropdown)
	button:SetWidth(24)
	button:SetHeight(24)
	button:SetPoint("BOTTOMRIGHT")
	button:SetNormalTexture("Interface\\ChatFrame\\UI-ChatIcon-ScrollDown-Up")
	button:SetPushedTexture("Interface\\ChatFrame\\UI-ChatIcon-ScrollDown-Down")
	button:SetDisabledTexture("Interface\\ChatFrame\\UI-ChatIcon-ScrollDown-Disabled")
	button:SetHighlightTexture("Interface\\Buttons\\UI-Common-MouseHilight")
	button:GetHighlightTexture():SetBlendMode("ADD")
	button:SetScript("OnClick", Dropdown_OnClick)


		-- Selected text.
	local selected = dropdown:CreateFontString(nil, "OVERLAY", "GameFontHighlightSmall")
	selected:SetPoint("LEFT", left, "RIGHT")
	selected:SetPoint("RIGHT", button, "LEFT")
	selected:SetJustifyH("RIGHT")


	-- Extension functions.
	dropdown.Configure			= Dropdown_Configure
	dropdown.SetListboxHeight	= Dropdown_SetListboxHeight
	dropdown.SetListboxWidth	= Dropdown_SetListboxWidth
	dropdown.SetLabel			= Dropdown_SetLabel
	dropdown.SetTooltip		= Dropdown_SetTooltip
	dropdown.SetChangeHandler	= Dropdown_SetChangeHandler
	dropdown.HideSelections	= Dropdown_HideSelections
	dropdown.AddItem			= Dropdown_AddItem
	dropdown.RemoveItem		= Dropdown_RemoveItem
	dropdown.Clear				= Dropdown_Clear
	dropdown.GetSelectedText	= Dropdown_GetSelectedText
	dropdown.GetSelectedID		= Dropdown_GetSelectedID
	dropdown.SetSelectedID		= Dropdown_SetSelectedID
	dropdown.Sort				= Dropdown_Sort
	dropdown.Disable			= Dropdown_Disable
	dropdown.Enable			= Dropdown_Enable

	-- Track internal values.
	dropdown.selectedFontString = selected
	dropdown.buttonFrame = button
	dropdown.labelFontString = label
	dropdown.items = {}
	dropdown.itemIDs = {}
	dropdown.selectedItem = 0
	return dropdown
end


-------------------------------------------------------------------------------
-- Editbox functions.
-------------------------------------------------------------------------------

-- ****************************************************************************
-- Called when the editbox has focus and escape is pressed.
-- ****************************************************************************
local function Editbox_OnEscape(this)
	this:ClearFocus()
	local editbox = this:GetParent()
	if (editbox.escapeHandler) then editbox:escapeHandler() end
end


-- ****************************************************************************
-- Called when the editbox loses focus.
-- ****************************************************************************
local function Editbox_OnFocusLost(this)
	this:HighlightText(0, 0)
end


-- ****************************************************************************
-- Called when the editbox gains focus.
-- ****************************************************************************
local function Editbox_OnFocusGained(this)
	this:HighlightText()
end


-- ****************************************************************************
-- Called when the text in the editbox changes.
-- ****************************************************************************
local function Editbox_OnTextChanged(this)
	local editbox = this:GetParent()
	if (editbox.textChangedHandler) then editbox:textChangedHandler() end
end


-- ****************************************************************************
-- Called when the mouse enters the editbox.
-- ****************************************************************************
local function Editbox_OnEnter(this)
	if (this.tooltip) then
		GameTooltip:SetOwner(this, this.tooltipAnchor or "ANCHOR_RIGHT")
		GameTooltip:SetText(this.tooltip, nil, nil, nil, nil, 1)
	end
end


-- ****************************************************************************
-- Called when the mouse leaves the editbox.
-- ****************************************************************************
local function Editbox_OnLeave(this)
	GameTooltip:Hide()
end


-- ****************************************************************************
-- Sets the label for the editbox.
-- ****************************************************************************
local function Editbox_SetLabel(this, label)
	this.labelFontString:SetText(label)
end


-- ****************************************************************************
-- Sets the tooltip for the editbox.
-- ****************************************************************************
local function Editbox_SetTooltip(this, tooltip)
	this.editboxFrame.tooltip = tooltip
end


-- ****************************************************************************
-- Configures the editbox.
-- ****************************************************************************
local function Editbox_Configure(this, width, label, tooltip)
	-- Don't do anything if required parameters are invalid.
	if (not width) then return end

	this:SetWidth(width)
	Editbox_SetLabel(this, label)
	Editbox_SetTooltip(this, tooltip)
end


-- ****************************************************************************
-- Sets the handler to be called when the enter button is pressed.
-- ****************************************************************************
local function Editbox_SetEnterHandler(this, handler)
	this.editboxFrame:SetScript("OnEnterPressed", handler)
end


-- ****************************************************************************
-- Sets the handler to be called when the escape button is pressed.
-- ****************************************************************************
local function Editbox_SetEscapeHandler(this, handler)
	this.escapeHandler = handler
end


-- ****************************************************************************
-- Sets the handler to be called when the text in the editbox changes.
-- ****************************************************************************
local function Editbox_SetTextChangedHandler(this, handler)
	this.textChangedHandler = handler
end


-- ****************************************************************************
-- Sets the focus to the editbox.
-- ****************************************************************************
local function Editbox_SetFocus(this)
	this.editboxFrame:SetFocus()
end


-- ****************************************************************************
-- Gets the text entered in the editbox.
-- ****************************************************************************
local function Editbox_GetText(this)
	return this.editboxFrame:GetText()
end


-- ****************************************************************************
-- Sets the text entered in the editbox.
-- ****************************************************************************
local function Editbox_SetText(this, text)
	return this.editboxFrame:SetText(text or "")
end


-- ****************************************************************************
-- Disables the editbox.
-- ****************************************************************************
local function Editbox_Disable(this)
	this.editboxFrame:EnableMouse(false)
	this.labelFontString:SetTextColor(0.5, 0.5, 0.5)
end

-- ****************************************************************************
-- Enables the editbox.
-- ****************************************************************************
local function Editbox_Enable(this)
	this.editboxFrame:EnableMouse(true)
	this.labelFontString:SetTextColor(NORMAL_FONT_COLOR.r, NORMAL_FONT_COLOR.g, NORMAL_FONT_COLOR.b)
end


-- ****************************************************************************
-- Creates and returns an editbox object ready to be configured.
-- ****************************************************************************
local function CreateEditbox(parent)
	-- Create container frame.
	local editbox = CreateFrame("Frame", nil, parent)
	editbox:SetHeight(32)

	-- Create editbox frame.
	local editboxFrame = CreateFrame("Editbox", nil, editbox)
	editboxFrame:SetHeight(20)
	editboxFrame:SetPoint("BOTTOMLEFT", editbox, "BOTTOMLEFT", 5, 0)
	editboxFrame:SetPoint("BOTTOMRIGHT")
	editboxFrame:SetAutoFocus(false)
	editboxFrame:SetFontObject(ChatFontNormal)
	editboxFrame:SetScript("OnEscapePressed", Editbox_OnEscape)
	editboxFrame:SetScript("OnEditFocusLost", Editbox_OnFocusLost)
	editboxFrame:SetScript("OnEditFocusGained", Editbox_OnFocusGained)
	editboxFrame:SetScript("OnTextChanged", Editbox_OnTextChanged)
	editboxFrame:SetScript("OnEnter", Editbox_OnEnter)
	editboxFrame:SetScript("OnLeave", Editbox_OnLeave)

	-- Left border.
	local left = editboxFrame:CreateTexture(nil, "BACKGROUND")
	left:SetTexture("Interface\\Common\\Common-Input-Border")
	left:SetWidth(8)
	left:SetHeight(20)
	left:SetPoint("LEFT", editboxFrame, "LEFT", -5, 0)
	left:SetTexCoord(0, 0.0625, 0, 0.625)

	-- Right border.
	local right = editboxFrame:CreateTexture(nil, "BACKGROUND")
	right:SetTexture("Interface\\Common\\Common-Input-Border")
	right:SetWidth(8)
	right:SetHeight(20)
	right:SetPoint("RIGHT")
	right:SetTexCoord(0.9375, 1, 0, 0.625)

	-- Middle border.
	local middle = editboxFrame:CreateTexture(nil, "BACKGROUND")
	middle:SetTexture("Interface\\Common\\Common-Input-Border")
	middle:SetWidth(10)
	middle:SetHeight(20)
	middle:SetPoint("LEFT", left, "RIGHT", 0, 0)
	middle:SetPoint("RIGHT", right, "LEFT", 0, 0)
	middle:SetTexCoord(0.0625, 0.9375, 0, 0.625)


	-- Label.
	local label = editbox:CreateFontString(nil, "OVERLAY", "GameFontNormalSmall")
	label:SetPoint("TOPLEFT")
	label:SetPoint("TOPRIGHT")
	label:SetJustifyH("LEFT")


	-- Extension functions.
	editbox.Configure				= Editbox_Configure
	editbox.SetLabel				= Editbox_SetLabel
	editbox.SetTooltip				= Editbox_SetTooltip
	editbox.SetEnterHandler		= Editbox_SetEnterHandler
	editbox.SetEscapeHandler		= Editbox_SetEscapeHandler
	editbox.SetTextChangedHandler	= Editbox_SetTextChangedHandler
	editbox.SetFocus				= Editbox_SetFocus
	editbox.GetText				= Editbox_GetText
	editbox.SetText				= Editbox_SetText
	editbox.Disable				= Editbox_Disable
	editbox.Enable					= Editbox_Enable


	-- Track internal values.
	editbox.editboxFrame = editboxFrame
	editbox.labelFontString = label
	return editbox
end


-------------------------------------------------------------------------------
-- Colorswatch functions.
-------------------------------------------------------------------------------

-- ****************************************************************************
-- Sets the color of the colorswatch.
-- ****************************************************************************
local function Colorswatch_SetColor(this, r, g, b)
	this.r = r
	this.g = g
	this.b = b
	this:GetNormalTexture():SetVertexColor(r, g, b)
end


-- ****************************************************************************
-- Called when the color picker values change.
-- ****************************************************************************
local function Colorswatch_ColorPickerOnChange(this)
	local colorswatch = ColorPickerFrame.associatedColorSwatch
	if (not colorswatch) then return end

	Colorswatch_SetColor(colorswatch, ColorPickerFrame:GetColorRGB())
	if (colorswatch.colorChangedHandler) then colorswatch:colorChangedHandler() end
end


-- ****************************************************************************
-- Called when the color picker values change.
-- ****************************************************************************
local function Colorswatch_ColorPickerOnCancel(previousValues)
	local colorswatch = ColorPickerFrame.associatedColorSwatch
	if (not colorswatch) then return end

	Colorswatch_SetColor(colorswatch, previousValues.r, previousValues.g, previousValues.b)
	if (colorswatch.colorChangedHandler) then colorswatch:colorChangedHandler() end
end


-- ****************************************************************************
-- Called when the colorswatch is clicked.
-- ****************************************************************************
local function Colorswatch_OnClick(this)
	local tempR = this.r or 1
	local tempG = this.g or 1
	local tempB = this.b or 1

	ColorPickerFrame.associatedColorSwatch = this
	ColorPickerFrame.hasOpacity = false
	ColorPickerFrame.opacity = 1
	ColorPickerFrame.previousValues = {r = tempR, g = tempG, b = tempB}
	ColorPickerFrame.func = Colorswatch_ColorPickerOnChange
	ColorPickerFrame.cancelFunc = Colorswatch_ColorPickerOnCancel
	ColorPickerFrame:SetColorRGB(tempR, tempG, tempB)
	ColorPickerFrame:ClearAllPoints()
	ColorPickerFrame:SetPoint("CENTER", this, "CENTER")
	ColorPickerFrame:Show()
end


-- ****************************************************************************
-- Called when the mouse enters the colorswatch.
-- ****************************************************************************
local function Colorswatch_OnEnter(this)
	if (this.tooltip) then
		GameTooltip:SetOwner(this, this.tooltipAnchor or "ANCHOR_RIGHT")
		GameTooltip:SetText(this.tooltip, nil, nil, nil, nil, 1)
	end

	this.borderTexture:SetVertexColor(NORMAL_FONT_COLOR.r, NORMAL_FONT_COLOR.g, NORMAL_FONT_COLOR.b)
end


-- ****************************************************************************
-- Called when the mouse leaves the colorswatch.
-- ****************************************************************************
local function Colorswatch_OnLeave(this)
	GameTooltip:Hide()
	this.borderTexture:SetVertexColor(HIGHLIGHT_FONT_COLOR.r, HIGHLIGHT_FONT_COLOR.g, HIGHLIGHT_FONT_COLOR.b)
end


-- ****************************************************************************
-- Sets the handler to be called when the color changes.
-- ****************************************************************************
local function Colorswatch_SetColorChangedHandler(this, handler)
	this.colorChangedHandler = handler
end


-- ****************************************************************************
-- Sets the tooltip for the colorswatch.
-- ****************************************************************************
local function Colorswatch_SetTooltip(this, tooltip)
	this.tooltip = tooltip
end


-- ****************************************************************************
-- Disables the colorswatch.
-- ****************************************************************************
local function Colorswatch_Disable(this)
	this:GetNormalTexture():SetVertexColor(0.5, 0.5, 0.5)
	this:oldDisableHandler()
end


-- ****************************************************************************
-- Enables the colorswatch.
-- ****************************************************************************
local function Colorswatch_Enable(this)
	this:oldEnableHandler()
	this:GetNormalTexture():SetVertexColor(this.r, this.g, this.b)
end


-- ****************************************************************************
-- Creates and returns a colorswatch object ready to be configured.
-- ****************************************************************************
local function CreateColorswatch(parent)
	-- Create button frame.
	local colorswatch = CreateFrame("Button", nil, parent)
	colorswatch:SetWidth(16)
	colorswatch:SetHeight(16)
	colorswatch:SetNormalTexture("Interface\\ChatFrame\\ChatFrameColorSwatch")
	colorswatch:SetScript("OnClick", Colorswatch_OnClick)
	colorswatch:SetScript("OnEnter", Colorswatch_OnEnter)
	colorswatch:SetScript("OnLeave", Colorswatch_OnLeave)


	-- Border texture.
	local texture = colorswatch:CreateTexture(nil, "BACKGROUND")
	texture:SetTexture("Interface\\ChatFrame\\ChatFrameBackground")
	texture:SetWidth(14)
	texture:SetHeight(14)
	texture:SetPoint("CENTER")
	texture:SetVertexColor(HIGHLIGHT_FONT_COLOR.r, HIGHLIGHT_FONT_COLOR.g, HIGHLIGHT_FONT_COLOR.b)

	-- Save old disable/enable handlers.
	colorswatch.oldDisableHandler = colorswatch.Disable
	colorswatch.oldEnableHandler = colorswatch.Enable

	-- Extension functions.
	colorswatch.SetColorChangedHandler	= Colorswatch_SetColorChangedHandler
	colorswatch.SetTooltip				= Colorswatch_SetTooltip
	colorswatch.SetColor				= Colorswatch_SetColor
	colorswatch.Disable				= Colorswatch_Disable
	colorswatch.Enable					= Colorswatch_Enable

	-- Track internal values.
	colorswatch.borderTexture = texture
	return colorswatch
end




-------------------------------------------------------------------------------
-- Module interface.
-------------------------------------------------------------------------------

-- Protected Functions.
module.CreateListbox			= CreateListbox
module.CreateCheckbox			= CreateCheckbox
module.CreateOptionButton		= CreateOptionButton
module.CreateIconButton			= CreateIconButton
module.CreateSlider				= CreateSlider
module.CreateDropdown			= CreateDropdown
module.CreateEditbox			= CreateEditbox
module.CreateColorswatch		= CreateColorswatch
