# Copyright (C) 2011-2012 Tanaka Akira  <akr@fsij.org>
#
# Redistribution and use in source and binary forms, with or without
# modification, are permitted provided that the following conditions
# are met:
#
#  1. Redistributions of source code must retain the above copyright
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#     copyright notice, this list of conditions and the following
#     disclaimer in the documentation and/or other materials provided
#     with the distribution.
#  3. The name of the author may not be used to endorse or promote
#     products derived from this software without specific prior
#     written permission.
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Tb::Cmd.subcommands << 'sort'

Tb::Cmd.default_option[:opt_sort_f] = nil
Tb::Cmd.default_option[:opt_sort_r] = nil

def (Tb::Cmd).op_sort
  op = OptionParser.new
  op.banner = "Usage: tb sort [OPTS] [TABLE]\n" +
    "Sort rows."
  define_common_option(op, "hNo", "--no-pager")
  op.def_option('-f FIELD,...', 'specify sort keys') {|fs| Tb::Cmd.opt_sort_f = fs }
  op.def_option('-r', '--reverse', 'reverse order') { Tb::Cmd.opt_sort_r = true }
  op
end

Tb::Cmd.def_vhelp('sort', <<'End')
Example:

  % cat tst.csv
  name,value
  foo,1
  bar,8
  baz,2
  % tb sort tst.csv
  name,value
  bar,8
  baz,2
  foo,1
  % tb sort -f value tst.csv
  name,value
  foo,1
  baz,2
  bar,8
End

def (Tb::Cmd).main_sort(argv)
  op_sort.parse!(argv)
  exit_if_help('sort')
  argv = ['-'] if argv.empty?
  if Tb::Cmd.opt_sort_f
    fs = split_field_list_argument(Tb::Cmd.opt_sort_f)
  else
    fs = nil
  end
  creader = Tb::CatReader.open(argv, Tb::Cmd.opt_N)
  header = []
  if fs
    blk = lambda {|pairs| fs.map {|f| Tb::Func.smart_cmp_value(pairs[f]) } }
  else
    blk = lambda {|pairs| header.map {|f| Tb::Func.smart_cmp_value(pairs[f]) } }
  end
  if Tb::Cmd.opt_sort_r
    blk1 = blk
    blk = lambda {|pairs| Tb::RevCmp.new(blk1.call(pairs)) }
  end
  er = Tb::Enumerator.new {|y|
    creader.with_cumulative_header {|header0|
      if header0
        y.set_header(header0)
      end
    }.each {|pairs, header1|
      header = header1
      y.yield pairs
    }
  }.extsort_by(&blk)
  output_tbenum(er)
end


