# frozen_string_literal: true
require 'etc'
require 'open3'
require 'media_tools'

module Booru
  module ImageProcessing
    module ShellHelper
      FFMPEG_COMMAND_BASE = [
        'ffmpeg',
        '-loglevel', 'warning', # don't be overly verbose in the logs
        '-threads', (Etc.nprocessors / 2).to_s, # don't use all our CPUs
        '-y' # overwrite existing files without asking
      ]

      def exec(cmd)
        write_log("EXEC: #{cmd}")
        output = `#{cmd} 2>&1`
        if output.present?
          write_log("OUTPUT\n#{output}\n")
        else
          write_log('<no output>')
        end

        output
      end

      def exec_new(tag, command_and_args)
        write_log("#{tag}: #{command_and_args.join(' ')}")
        output, stderr, status = Open3.capture3(*command_and_args)

        write_log("exit code: #{status}")
        write_log(output.blank? ? '<no output>' : "OUTPUT\n#{output}\n")
        write_log("STDERR\n#{stderr}") if stderr.present?

        raise "#{tag} returned exit status: #{status}" if status != 0

        output
      end

      def ffmpeg(*ffmpeg_args)
        exec_new('FFMPEG', FFMPEG_COMMAND_BASE + ffmpeg_args)
      end

      def optipng(path)
        exec_new 'OPTIPNG', ['nice', '-n', '19', 'optipng', '-quiet', '-fix', '-i0', '-o3', path]
      end

      def jpegtran(path)
        exec_new 'JPEGTRAN', ['nice', '-n', '19', 'jpegtran', '-optimize', '-outfile', path, path]
      end

      def generate_thumb(path, time, dest_path)
        write_log "generate_thumb(\"#{path}\", #{time}, \"#{dest_path}\")"
        result = MediaTools.generate_thumb(path, time, dest_path)
        write_log("result: #{result}")
      end
    end
  end
end