require 'erb'
module MetricFu

  TEMPLATE_DIR = File.join(File.dirname(__FILE__), '..', 'templates')
  BASE_DIRECTORY = ENV['CC_BUILD_ARTIFACTS'] || 'tmp/metric_fu'

  class << self
    # The Configuration instance used to configure the Rails environment
    def configuration
      @@configuration ||= Configuration.new
    end

    def churn
      configuration.churn
    end

    def coverage
      configuration.coverage
    end

    def flay
      configuration.flay
    end

    def flog
      configuration.flog
    end

    def metrics
      configuration.metrics
    end

    def open_in_browser?
      configuration.general[:open_in_browser] && PLATFORM['darwin'] && !run_by_cruise_control?
    end
    
    def saikuro
      configuration.saikuro
    end

    def reek
      configuration.reek
    end    

    def roodi
      configuration.roodi
    end

    def run_by_cruise_control?
      !!ENV['CC_BUILD_ARTIFACTS']
    end

    def uses_git?
      File.exist?(".git")      
    end
    
    def uses_svn?
      File.exist?(".svn")
    end
    
    def can_churn?
      uses_git? || uses_svn?
    end
    
    def is_rails?
      File.exist?("config/environment.rb")
    end
    
    def code_dirs
      dirs = ['lib']
      dirs << 'app' if is_rails?
      dirs.sort{|v1, v2| v1.to_s <=> v2.to_s}
    end
    
    def default_metrics
      metrics = [:coverage, :flog, :flay, :reek, :roodi, :saikuro ]      
      metrics << :stats if is_rails?
      # Churning requires a subversion or git repo
      metrics << :churn if can_churn?
      metrics.sort{|v1, v2| v1.to_s <=> v2.to_s}
    end
    
  end
  
  class Configuration
    attr_accessor :churn, :coverage, :flay, :flog, :metrics, :reek, :roodi, :saikuro, :general
    def initialize
      raise "Use config.churn instead of MetricFu::CHURN_OPTIONS" if defined? ::MetricFu::CHURN_OPTIONS
      raise "Use config.flog[:dirs_to_flog] instead of MetricFu::DIRECTORIES_TO_FLOG" if defined? ::MetricFu::DIRECTORIES_TO_FLOG
      raise "Use config.saikuro instead of MetricFu::SAIKURO_OPTIONS" if defined? ::MetricFu::SAIKURO_OPTIONS      
      reset      
    end
    
    def self.run()  
      yield MetricFu.configuration
    end
    
    def reset
      @general  = { :open_in_browser => true }
      @churn    =  {}
      rcov_opts =  ["--sort coverage", "--html", "--exclude /gems/,/Library/,spec"]
      rcov_opts << "--rails" if MetricFu.is_rails?
      @coverage = { :test_files => ['test/**/*_test.rb', 'spec/**/*_spec.rb'],
                    :rcov_opts => rcov_opts }
      @flay     = { :dirs_to_flay => MetricFu.code_dirs}
      @flog     = { :dirs_to_flog => MetricFu.code_dirs}
      @reek     = { :dirs_to_reek => MetricFu.code_dirs}
      @roodi    = { :dirs_to_roodi => MetricFu.code_dirs}
      @metrics          = MetricFu.default_metrics
      @saikuro  = {}
    end
    
    def saikuro=(options)
      raise "saikuro need to be a Hash" unless options.is_a?(Hash)
      @saikuro = options
    end
  end

  module Base
    
    ######################################################################
    # Base class for report Generators
    #
    class Generator

      def initialize(options={})
        @base_dir = self.class.metric_dir
      end

      def self.metric_dir
        File.join(BASE_DIRECTORY, template_name)        
      end
      
      def self.template_name
        self.to_s.split('::').last.downcase
      end      

      def self.generate_report(options={})
        FileUtils.mkdir_p(metric_dir, :verbose => false) unless File.directory?(metric_dir)
        self.new(options).generate_report
      end

      def save_html(content, file='index.html')
        open("#{@base_dir}/#{file}", "w") do |f|
          f.puts content
        end
      end

      def generate_report
        save_html(generate_html)
      end

      def generate_html
        analyze
        html = ERB.new(File.read(template_file)).result(binding)
      end
      
      def template_name
        self.class.template_name
      end

      def template_file
        File.join(MetricFu::TEMPLATE_DIR, "#{template_name}.html.erb")
      end      
      
      ########################
      # Template methods
      
      def inline_css(css)
	      open(File.join(MetricFu::TEMPLATE_DIR, css)) { |f| f.read }      
      end
      
      def link_to_filename(name, line = nil)
        if MetricFu.run_by_cruise_control?
          cc_link_to_filename(name, line)
        else
          system_link_to_filename(name, line)
        end
      end
      
      def cycle(first_value, second_value, iteration)
        return first_value if iteration % 2 == 0
        return second_value
      end      
      
      private
      def cc_link_to_filename(name, line = nil)
        if MetricFu.configuration.general[:url_prefix]
          MetricFu.configuration.general[:url_prefix] += '/' unless MetricFu.configuration.general[:url_prefix] =~ /\/$/
          %{<a href="#{MetricFu.configuration.general[:url_prefix]}#{name}?line=#{line}##{line}">#{name}</a>}
        else
          %{"#{name}"} # No link for cruise control without a prefix
        end
      end 
      
      def system_link_to_filename(name, line = nil)
        filename = File.expand_path(name)
        if PLATFORM['darwin']
          %{<a href="txmt://open/?url=file://#{filename}&line=#{line}">#{name}</a>}
        else
          %{<a href="file://#{filename}">#{name}</a>}
        end
      end
    end
  end
  
end