# frozen_string_literal: true

require 'json'
require 'pathname'

module RuboCop
  module Formatter
    # This formatter formats the report data in JSON format.
    class JSONFormatter < BaseFormatter
      include PathUtil

      attr_reader :output_hash

      def initialize(output, options = {})
        super
        @output_hash = {
          metadata: metadata_hash,
          files: [],
          summary: { offense_count: 0 }
        }
      end

      def started(target_files)
        output_hash[:summary][:target_file_count] = target_files.count
      end

      def file_finished(file, offenses)
        output_hash[:files] << hash_for_file(file, offenses)
        output_hash[:summary][:offense_count] += offenses.count
      end

      def finished(inspected_files)
        output_hash[:summary][:inspected_file_count] = inspected_files.count
        output.write output_hash.to_json
      end

      def metadata_hash
        {
          rubocop_version: RuboCop::Version::STRING,
          ruby_engine: RUBY_ENGINE,
          ruby_version: RUBY_VERSION,
          ruby_patchlevel: RUBY_PATCHLEVEL.to_s,
          ruby_platform: RUBY_PLATFORM
        }
      end

      def hash_for_file(file, offenses)
        {
          path: smart_path(file),
          offenses: offenses.map { |o| hash_for_offense(o) }
        }
      end

      def hash_for_offense(offense)
        {
          severity: offense.severity.name,
          message: offense.message,
          cop_name: offense.cop_name,
          corrected: offense.corrected?,
          location: hash_for_location(offense)
        }
      end

      # TODO: Consider better solution for Offense#real_column.
      def hash_for_location(offense)
        {
          start_line: offense.line,
          start_column: offense.real_column,
          last_line: offense.last_line,
          last_column: offense.last_column,
          length: offense.location.length,
          # `line` and `column` exist for compatibility.
          # Use `start_line` and `start_column` instead.
          line: offense.line,
          column: offense.real_column
        }
      end
    end
  end
end
