#!/usr/bin/env bash
# This approach was adapted from https://gist.github.com/domenic/ec8b0fc8ab45f39403dd

THIS_DIR="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"

cd $THIS_DIR

git config --global user.name "$COMMIT_AUTHOR_NAME"
git config --global user.email "$COMMIT_AUTHOR_EMAIL"

set -e # Exit with nonzero exit code if anything fails

SOURCE_BRANCH="master"
TARGET_BRANCH="gh-pages"

function doCompile {
  ./compile.sh
}

# Pull requests and commits to other branches shouldn't try to deploy, just build to verify
if [ "$TRAVIS_PULL_REQUEST" != "false" -o "$TRAVIS_BRANCH" != "$SOURCE_BRANCH" ]; then
    echo "Skipping deploy; just doing a build."
    doCompile
    exit 0
fi

# Save some useful information
REPO=`git config remote.origin.url`
SSH_REPO=${REPO/https:\/\/github.com\//git@github.com:}
SHA=`git rev-parse --verify HEAD`

# Run our compile script
doCompile

# Get the deploy key by using Travis's stored variables to decrypt deploy_key.enc
ENCRYPTED_KEY_VAR="encrypted_${ENCRYPTION_LABEL}_key"
ENCRYPTED_IV_VAR="encrypted_${ENCRYPTION_LABEL}_iv"
ENCRYPTED_KEY=${!ENCRYPTED_KEY_VAR}
ENCRYPTED_IV=${!ENCRYPTED_IV_VAR}

openssl aes-256-cbc -K $ENCRYPTED_KEY -iv $ENCRYPTED_IV -in deploy_key.enc -out deploy_key -d
chmod 600 deploy_key
eval `ssh-agent -s`
ssh-add deploy_key

# Clone the existing gh-pages for this repo into out/
# Create a new empty branch if gh-pages doesn't exist yet (should only happen on first deply)
git clone $REPO out
cd out
git checkout $TARGET_BRANCH || git checkout --orphan $TARGET_BRANCH

# Clean out existing contents
git ls-files | xargs rm -rf

mv ../README.html ./index.html

# Commit the "changes", i.e. the new version.
# The delta will show diffs between new and old versions.
git add --all .
git commit -m "Deploy to GitHub Pages: ${SHA}"

git fetch origin master

if [ "$(git rev-parse origin/master)" == "$SHA" ]; then
  git push "$SSH_REPO" "$TARGET_BRANCH"
else
    echo "The commit this build was started for is not the one on master. Doing nothing."
fi
