# PublishR -- Fast publishing for ebooks and paper
# Copyright (C) 2012 Michael Franzl
# 
# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as
# published by the Free Software Foundation, either version 3 of the
# License, or (at your option) any later version.
# 
# 
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.
#
# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

module Publishr
  class EpubRenderer
    def initialize(name,inpath,outpath,metadata,rails_resources_url='')
      @name = name
      @inpath = inpath
      @outpath = outpath
      @metadata = metadata
      @gempath = Publishr::gempath
      @rails_resources_url = rails_resources_url

      @html_files = []
      @image_files = []
    end

    def render
      make_epub_directory_structure
      render_htmls
      compile_xmls
    end

    def make_epub_directory_structure
      FileUtils.rm_rf @outpath
      FileUtils.cp_r File.join(@gempath,'lib','epub_skeleton'), @outpath
      FileUtils.cp Dir[File.join(@inpath,'images','*.jpg')], @outpath
      FileUtils.cp File.join(@inpath,'cover.jpg'), @outpath
      @image_files = Dir[File.join(@outpath,'*.jpg')]
      # users can provide an overriding css file
      FileUtils.cp_f File.join(@inpath,'epub.css'), @outpath if File.exists?(File.join(@inpath,'epub.css'))
    end

    def render_htmls
      kramdown_options = {
        :auto_ids => false,
        :smart_quotes => @metadata['kramdown_options']['smart_quotes'],
        :template => File.join(@gempath,'lib','epub_templates','kramdown.html')
      }
      Dir[File.join(@inpath,'*.txt')].each do |infilepath|
        kramdown = File.open(infilepath, 'r').read
        html = Kramdown::Document.new(kramdown, kramdown_options).to_html
        degraded_html = HtmlProcessor.new(html,@inpath,@metadata,@rails_resources_url).degrade
        outfilepath = File.join(@outpath, File.basename(infilepath).gsub(/(.*).txt/, '\1.html'))
        File.open(outfilepath, 'w'){ |f| f.write degraded_html }
      end
      @html_files = ([File.join(@outpath,'covertext.html')] + [File.join(@outpath,'frontmatter.html')] + [File.join(@outpath,'toc.html')] + Dir[File.join(@outpath,'*.html')].sort).uniq
    end

    def compile_xmls
      File.open(File.join(@outpath,'content.opf'),'w'){ |f| f.write render_content_opf }
      File.open(File.join(@outpath,'toc.ncx'),'w'){ |f| f.write render_toc_ncx     }
      Dir.chdir @outpath
      filename = File.join(@inpath,"#{ @name }.epub")
      `zip -X0 #{ filename } mimetype`
      `zip -Xur9D #{ filename } *`
    end

    def render_content_opf
      erb = File.open(File.join(@gempath,'lib','epub_templates','content.opf.erb'),'r').read
      spine_items = render_spine_items
      manifest_items = render_manifest_items
      ERB.new(erb).result binding
    end

    def render_toc_ncx
      erb = File.open(File.join(@gempath,'lib','epub_templates','toc.ncx.erb'),'r').read
      nav_points = render_nav_points
      ERB.new(erb).result binding
    end

    def render_nav_points
      erb = File.open(File.join(@gempath,'lib','epub_templates','nav_points.erb'),'r').read
      results = []
      i = 0
      @html_files.each do |h|
        filename = File.basename(h)
        id = filename.gsub '.',''
        i += 1
        results << (ERB.new(erb).result binding)
      end
      results.join("\n")
    end

    def render_manifest_items
      image_files = Dir[File.join(@outpath,'*.jpg')]
      erb = File.open(File.join(@gempath,'lib','epub_templates','manifest_items.erb'),'r').read
      results = []
      (@html_files + @image_files).each do |h|
        filename = File.basename(h)
        id = filename.gsub '.',''
        mediatype = case File.extname(h) 
          when '.html' then 'application/xhtml+xml'
          when '.jpg' then 'image/jpeg'
          when '.png' then 'image/png'
        end
        results << (ERB.new(erb).result binding)
      end
      results.join("\n")
    end

    def render_spine_items
      erb = File.open(File.join(@gempath,'lib','epub_templates','spine_items.erb'),'r').read
      results = []
      @html_files.each do |h|
        id = File.basename(h).gsub '.',''
        results << (ERB.new(erb).result binding)
      end
      results.join("\n")
    end
    

  end
end