require "musedown/version"
require "thor"

module Musedown
    class Score
        attr_accessor :score_file
        attr_accessor :relative_score_file
        attr_accessor :relative_image_file
        attr_reader :prebuilt

        def initialize(prebuilt)
            @score_file = nil
            @relative_score_file = nil
            @relative_image_file = nil
            @prebuilt = prebuilt
        end

        def build(command)
            begin
                image_file = "#{@score_file.gsub(".mscz", "-mscz")}.png"
                result = `#{command} #{@score_file} -o #{image_file}`
            rescue Errno::ENOENT => error
                puts("⚠️ Error building #{@score_file}: #{error}")
            end

            if $?.success?
                if !prebuilt
                    @relative_image_file = @relative_score_file.sub(/.*\K\.mscz/, "-mscz-1.png")
                end
            else
                puts("⚠️ Failed to convert #{@score_file}")
            end
            return $?.success?
        end
    end

    class CLI < Thor
        desc("build [FILE_NAME]", "build markdown file")
        option(:output, :type => :string, :required => false, :desc => "output file", :aliases => "-o")
        option(:command, :type => :string, :default => "mscore", :desc => "musescore command, default: mscore", :aliases => "-c")
        def build(file_name)
            output_file = file_name
            if options[:output]
                puts("✏️  Output file will be #{options[:output]}")
                output_file = options[:output]
            end

            puts("👷‍♂️ Building file #{file_name}...")
            contents = nil
            File.open(file_name) do |file|
                contents = file.read
            end
            scores = []

            prebuilt_expression = /!\[.*\]\((?<file_name>.*\-mscz-1\.png)\)/
            prebuilt_matches = contents.scan(prebuilt_expression)

            puts("🔍 Found #{prebuilt_matches.length} previously built images...")
            prebuilt_matches.each do |match|
                score = Score.new(true)
                score.relative_image_file = match[0]
                resolved_image_file = File.join(File.dirname(file_name), score.relative_image_file)
                score.score_file = resolved_image_file.gsub("-mscz-1.png", ".mscz")
                scores << score
            end

            expression = /!\[.*\]\((?<file_name>.*\.mscz)\)/
            matches = contents.scan(expression)

            puts("🔍 Found unbuilt #{matches.length} score files...")
            matches.each do |match|
                score = Score.new(false)
                score.relative_score_file = match[0]
                score.score_file = File.join(File.dirname(file_name), score.relative_score_file)
                scores << score
            end

            scores.each do |score|
                sucess = score.build(options[:command])
                if !score.prebuilt and sucess
                    contents = contents.gsub(score.relative_score_file, score.relative_image_file)
                end
            end

            puts("💾 Saving...")
            File.open(output_file, "w") do |file|
                file.write(contents)
            end

            puts "✅ Done!"
        end
    end
end