module Gumdrop

  class Generator
    attr_reader :filename, :base_path, :params, :pages
    
    def initialize(content, site, opts={})
      @site= site
      @content= content
      if @content.is_a? Proc
        @filename= ""
        @base_path= ""
      else
        @filename= content.filename || ""
        @base_path= content.slug || ""
      end
      @params= HashObject.new
      @pages= []
    end
    
    # This should probably not be accessible to the generators
    def execute
      if @content.is_a? Proc
        instance_eval &@content
      else
        instance_eval File.read(@content.path)
      end
    end

    def site
      @site
    end
    
    def data
      @site.data
    end

    def config
      @site.config
    end
    
    def set(var_name, value)
      params[var_name]= value
    end
    
    def page(name, opts={}, &block)
      name= name[1..-1] if name.starts_with?('/')
      opts= params.reverse_merge(opts)
      filepath= if @base_path.empty?
        File.join @site.src_path, name
      else
        File.join @site.src_path, @base_path, @name
      end
      content= GeneratedContent.new(filepath, block, @site, opts)
      if opts.has_key? :template and !opts[:template].nil?
        content.template = if @site.layouts.has_key?( opts[:template] )
          @site.layouts[ opts[:template] ]
        else
          @site.layouts[ "#{opts[:template]}.template" ]
        end.template
      end
      content.ignored= site.greylist.any? {|pattern| site.path_match name, pattern }
      unless content.ignored
        content.ignored= site.blacklist.any? {|pattern| site.path_match name, pattern }
      end      
      @site.report " generated: #{content.uri}", :info
      @site.node_tree[content.uri]= content
    end

    # FIXME: Does redirect require abs-paths?
    def redirect(from, opts={})
      if opts[:to]
        page from do
          <<-EOF
          <meta http-equiv="refresh" content="0;url=#{ opts[:to] }">
          <script> window.location.href='#{ opts[:to] }'; </script>
          EOF
        end
        opts[:from]= from
        @site.redirects << opts
      else
        @site.report "You must specify :to in a redirect", :warning
      end
    end
    
    def sprockets(name, opts)
      require 'gumdrop/sprockets_support'
      # require 'pp'
      env = Sprockets::Environment.new @site.root_path
      env.append_path @site.src_path
      opts[:paths].each do |path|
        env.append_path(path)
      end
      
      content= env[ opts[:src] ].to_s
      page name do
        compress_output(content, opts)
      end
      keep_src(name, content, opts)
      prune_src(name, opts)
    end
    
    def stitch(name, opts)
      require 'gumdrop/stitch_support'
      content= Stitch::Package.new(opts).compile
      page name do
        compress_output(content, opts)
      end
      keep_src(name, content, opts)
      prune_src(name, opts)
    end
    
    
  private
  
    def compress_output(content, opts)
      case opts[:compress]

      when true, :jsmin
        require 'jsmin'
        JSMin.minify content

      when :yuic
        require "yui/compressor"
        compressor = YUI::JavaScriptCompressor.new(:munge => opts[:obfuscate])
        compressor.compress(content)

      when :uglify
        require "uglifier"
        Uglifier.compile( content, :mangle=>opts[:obfuscate])

      when :packr
        require 'packr'
        Packr.pack(content, :shrink_vars => true, :base62 => false, :private=>false)

      when false
        content

      else
        # UNKNOWN Compressor type!
        @site.report "Unknown javascript compressor type! (#{ opts[:compressor] })", :warning
        content
      end
    end
    
    def keep_src(name, content, opts)
      if opts[:keep_src] or opts[:keep_source]
        ext= File.extname name
        page name.gsub(ext, "#{opts.fetch(:source_postfix, '-src')}#{ext}") do
          content
        end
      end
    end
    
    def prune_src(name, opts)
      if opts[:prune] and opts[:root]
        sp = File.expand_path( @site.config.source_dir )
        rp = File.expand_path(opts[:root])
        relative_root = rp.gsub(sp, '')[1..-1]
        rrlen= relative_root.length - 1
        @site.node_tree.keys.each do |path|
          if path[0..rrlen] == relative_root and name != path
            @site.node_tree.delete path
          end
        end
      end
    end
    
  end
  
  class GeneratedContent < Content
    # Nothing special, per se...

    def initialize(path, block, site, params={})
      super(path, site, params)
      @content_block= block
      @generated= true
    end

    def render(context=nil, ignore_layout=false,  reset_context=true, locals={})
      if @content_block.nil?
        super(context, ignore_layout, reset_context, locals)
      else
        @content_block.call
      end
    end

    def useLayout?
      !@content_block.nil? or !@template.nil?
    end

  end
  
end