module Slather
  class CoverageFile

    attr_accessor :project, :gcno_file_pathname

    def initialize(project, gcno_file_pathname)
      self.project = project
      self.gcno_file_pathname = Pathname(gcno_file_pathname)
    end

    def source_file_pathname
      @source_file_pathname ||= begin
        base_filename = gcno_file_pathname.basename.sub_ext("")
        # TODO: Handle Swift
        path = nil
        if project.source_directory
          path = Dir["#{project.source_directory}/**/#{base_filename}.m"].first
          path &&= Pathname(path)
        else
          pbx_file = project.files.detect { |pbx_file| pbx_file.real_path.basename.to_s == "#{base_filename}.m" }
          path = pbx_file && pbx_file.real_path
        end
        path
      end
    end

    def source_file
      File.new(source_file_pathname)
    end

    def source_data
      source_file.read
    end

    def source_file_pathname_relative_to_repo_root
      source_file_pathname.realpath.relative_path_from(Pathname("./").realpath)
    end

    def gcov_data
      @gcov_data ||= begin
        gcov_output = `gcov "#{source_file_pathname}" --object-directory "#{gcno_file_pathname.parent}"`
        # Sometimes gcov makes gcov files for Cocoa Touch classes, like NSRange. Ignore and delete later.
        gcov_files_created = gcov_output.scan(/creating '(.+\..+\.gcov)'/)

        gcov_file_name = "./#{source_file_pathname.basename}.gcov"
        if File.exists?(gcov_file_name)
          gcov_data = File.new(gcov_file_name).read
        end

        gcov_files_created.each { |file| FileUtils.rm_f(file) }

        gcov_data
      end
    end

    def coverage_data
      if gcov_data
        first_line_start = gcov_data =~ /^\s+(-|#+|[0-9+]):\s+1:/

        gcov_data[first_line_start..-1].split("\n").map do |line|
          coverage_for_line(line)
        end
      else
        []
      end
    end

    def coverage_for_line(line)
      line =~ /^(.+?):/

      match = $1.strip
      case match
      when /[0-9]+/
        match.to_i
      when /#+/
        0
      when "-"
        nil
      end
    end

    def num_lines_tested
      coverage_data.compact.select { |cd| cd > 0 }.count
    end

    def num_lines_testable
      coverage_data.compact.count
    end

    def percentage_lines_tested
      if num_lines_testable > 0 
        (num_lines_tested / num_lines_testable.to_f) * 100.0
      else
        0
      end
    end

    def ignored?
      project.ignore_list.any? do |ignore|
        File.fnmatch(ignore, source_file_pathname_relative_to_repo_root)
      end
    end

  end
end