usage 'show-data'
aliases :debug
summary 'show data in this site'
description <<-EOS
Show information about all items, item representations and layouts in the
current site, along with dependency information.
EOS

module Nanoc::CLI::Commands
  class ShowData < ::Nanoc::CLI::CommandRunner
    def run
      load_site(preprocess: true)

      # Get data
      items   = site.items
      layouts = site.layouts

      # Get dependency tracker
      compiler = site.compiler
      compiler.load_stores
      dependency_store = compiler.dependency_store

      # Print data
      print_item_dependencies(items, dependency_store)
      print_item_rep_paths(items)
      print_item_rep_outdatedness(items, compiler)
      print_layouts(layouts, compiler)
    end

    protected

    def sorted_with_prev(objects)
      prev = nil
      objects.sort_by(&:identifier).each do |object|
        yield(object, prev)
        prev = object
      end
    end

    def sorted_reps_with_prev(items)
      prev = nil
      items.sort_by(&:identifier).each do |item|
        site.compiler.reps[item].sort_by { |r| r.name.to_s }.each do |rep|
          yield(rep, prev)
          prev = rep
        end
      end
    end

    def print_header(title)
      header = '=' * 78
      header[3..(title.length + 5)] = " #{title} "

      puts
      puts header
      puts
    end

    def print_item_dependencies(items, dependency_store)
      print_header('Item dependencies')

      sorted_with_prev(items) do |item, prev|
        puts if prev
        puts "item #{item.identifier} depends on:"
        predecessors = dependency_store.objects_causing_outdatedness_of(item).sort_by { |i| i ? i.identifier : '' }
        predecessors.each do |pred|
          type =
            case pred
            when Nanoc::Int::Layout
              'layout'
            when Nanoc::Int::ItemRep
              'item rep'
            when Nanoc::Int::Item
              'item'
            end

          if pred
            puts "  [ #{format '%6s', type} ] #{pred.identifier}"
          else
            puts '  ( removed item )'
          end
        end
        puts '  (nothing)' if predecessors.empty?
      end
    end

    def print_item_rep_paths(items)
      print_header('Item representation paths')

      sorted_reps_with_prev(items) do |rep, prev|
        puts if prev
        puts "item #{rep.item.identifier}, rep #{rep.name}:"
        if rep.raw_paths.empty?
          puts '  (not written)'
        end
        length = rep.raw_paths.keys.map { |s| s.to_s.length }.max
        rep.raw_paths.each do |snapshot_name, raw_path|
          puts format("  [ %-#{length}s ] %s", snapshot_name, raw_path)
        end
      end
    end

    def print_item_rep_outdatedness(items, compiler)
      print_header('Item representation outdatedness')

      sorted_reps_with_prev(items) do |rep, prev|
        puts if prev
        puts "item #{rep.item.identifier}, rep #{rep.name}:"
        outdatedness_reason = compiler.outdatedness_checker.outdatedness_reason_for(rep)
        if outdatedness_reason
          puts "  is outdated: #{outdatedness_reason.message}"
        else
          puts '  is not outdated'
        end
      end
    end

    def print_layouts(layouts, compiler)
      print_header('Layouts')

      sorted_with_prev(layouts) do |layout, prev|
        puts if prev
        puts "layout #{layout.identifier}:"
        outdatedness_reason = compiler.outdatedness_checker.outdatedness_reason_for(layout)
        if outdatedness_reason
          puts "  is outdated: #{outdatedness_reason.message}"
        else
          puts '  is not outdated'
        end
        puts
      end
    end
  end
end

runner Nanoc::CLI::Commands::ShowData
