#! /usr/bin/env ruby

require 'json'
require 'optparse'

class FindRecentFiles

  def initialize
    @default_fd_filetype = 'f'
    @fd_allowed_filetypes = ["f", "d", "l", "s", "p", "x", "e"]
    @output_format = "text"
    @reverse = false
    @ignore_file = nil
    @filetypes = []
    @max_results = -1
    @changed_within = '7d'

    get_arguments
    check_paths
  end

  def run
    files = run_fd_command
    if @output_format == 'text'
      text_output(files)
    else
      json_output(files)
    end

  end

  private

  def get_arguments
    opts = OptionParser.new do |opts|
      opts.banner = "Usage: #$0 [options]"
      opts.on('-c', '--changed-within [STRING]', 'changed within 1h, 2d, 5min, etc.; the default is 7d') do |c|
        @changed_within = c
      end
      opts.on('-d', '--dir [STRING]', 'directory to start search from; the default is the current directory') do |d|
        @directory = d
      end
      opts.on('--fd-command [STRING]', 'path to the fd(1) command if not specified in $PATH') do |i|
        @fd_command = i
      end
      opts.on('-h') do
          puts opts
          exit
      end
      opts.on('-H', '--hidden', 'show hidden files; the default is not to show hidden files') do
        @show_hidden = true
      end
      opts.on('-i', '--ignore-file [STRING]', 'path to the Git-format ignore file for search exclusions, optional') do |i|
        @ignore_file = i
      end
      opts.on('-m', '--max-results [INT]', 'only return MAX_RESULTS items; the default is to return all results') do |m|
        @max_results = m.to_i
      end
      opts.on('-o', '--output-format [text or json]', 'output format, default is text; json is for use by Alfred') do |o|
        @output_format = o
      end
      opts.on('-r', '--reverse', 'reverse the sorting order; the default is newest files first') do
        @reverse = true
      end
      opts.on('-t', '--filetype [STRING]', 'filetype, as supported by fd; the default is \"f\"; the argument may be repeated or combined, so both (1) and (2)\ are allowed: (1) --filetype fd (2) --filetype f --filetype d') do |t|
        @filetypes << t
      end
    end

    opts.parse!(ARGV)

    if @filetypes.empty?
      @filetypes << @default_fd_filetype
    else
      @filetypes.each do |f|
        if not @fd_allowed_filetypes.include? f
          print "--filetype (or -t) must be one or more of: #{@fd_allowed_filetypes.join(',')}\n\n"
          puts opts
          exit 1
        end
      end
    end

    # If there's a funky output format, ignore it
    if @output_format != 'json'
      @output_format = 'text'
    end

    @fd_command = 'fd' if @fd_command.nil?
    @directory = Dir.pwd if @directory.nil?

  end

  def check_paths

    if not @ignore_file.nil?
      if File.exist? @ignore_file
        @ignore_file = File.expand_path(@ignore_file)
      else
        print "Error: -i/--ignore-file file does not exist: #{@ignore_file}\n"
        exit 1
      end
    end

  end

  def set_command_line_options
    options = ['-a']

    options << '--changed-within'
    options << @changed_within

    @filetypes.each do |f|
      options << '-t'
      options << f
    end

    if @ignore_file
      options << '--ignore-file'
      options << @ignore_file
    end

    options << '-H' if @show_hidden

    return options

  end

  def run_fd_command

    options = set_command_line_options
    files = {}

    Dir.chdir(@directory) do
      IO.popen([@fd_command, *options]) do |subprocess|
        subprocess.read.split("\n").each do |line|
          files[line] = File.stat(line).mtime.to_f
        end
      end
    end

    return files.sort_by {|k, v| v} if @reverse

    return files.sort_by {|k, v| -v}

  end

  def text_output(data)

    data.each_with_index do |f, index|
      break if index == @max_results
      print("#{f[0]}\n")
    end

  end

  def json_output(data)
    files = []
    result_count = 0

    data.each do |file|
      break if result_count == @max_results

      result_count += 1

      filename = file[0]
      record = {
        :type => "file",
        :title => filename,
        :subtitle => filename,
        :arg => filename,
        :icon => {
          :type => "fileicon",
          :path => filename
        }
      }
      files.append(record)

    end

    items = { :items => files }
    print JSON.generate(items)

  end

end

frf = FindRecentFiles.new
frf.run