#!/usr/bin/env ruby
# frozen_string_literal: true

require 'mtree'

require 'optparse'

options = {
  action: :check,
  group_mapping: {},
  user_mapping: {},
}

OptionParser.new do |opts|
  opts.banner = 'usage: mtree options'

  opts.on('-e', 'Noop.  For compatibility only') do
  end
  opts.on('-f', '--file=FILE', 'Read the specification from FILE instead of standard input') do |specification|
    options[:specification] = specification
  end

  opts.on('-p', '--path=PATH', 'Use the file hierarchy rooted in PATH, instead of the current directory') do |path|
    options[:root] = path
  end

  opts.on('-j', 'Indent the output 4 spaces each time a directory level is descended') do
    options[:indent] = true
  end

  opts.on('-u', '--update') do
    options[:action] = :update
  end

  # Extensions

  opts.on('--check', 'Checks that the files hierarchy match the specification') do
    options[:action] = :check
  end

  opts.on('--print', 'Print the transformed specification') do
    options[:action] = :print
  end

  opts.on('--leaves', 'Only consider leaves of the specification') do
    options[:leaves] = true
  end

  opts.on('--map-gname=MAPPING', 'Apply from:to MAPPING to the gname field') do |mapping|
    mapping.split(',').each do |tuple|
      from, to = tuple.split(':', 2)
      options[:group_mapping][from] = to
    end
  end

  opts.on('--map-uname=MAPPING', 'Apply from:to MAPPING to the uname field') do |mapping|
    mapping.split(',').each do |tuple|
      from, to = tuple.split(':', 2)
      options[:user_mapping][from] = to
    end
  end

  opts.on('--symlink-to=DESTINATION', '') do |destination|
    options[:symlink_to] = destination
  end
end.parse!

parser = Mtree::Parser.new
parser.parse_file(options[:specification])
specifications = parser.specifications

specifications.leaves! if options[:leaves]

options[:group_mapping].each do |from, to|
  specifications.each do |specification|
    specification.gname = to if specification.gname == from
  end
end

options[:user_mapping].each do |from, to|
  specifications.each do |specification|
    specification.uname = to if specification.uname == from
  end
end

specifications.symlink_to!(options[:symlink_to]) if options[:symlink_to]

case options[:action]
when :update
  specifications.enforce(options[:root] || '.')
when :check
  exit specifications.match?(options[:root] || '.') ? 0 : 2
when :print
  puts specifications.to_s(indent: options[:indent])
end