#!/usr/bin/env ruby

require 'yaml'
require 'optparse'
require 'digest'
require 'mini_magick'
require 'fileutils'
require 'erb'

def copyimage(path, file, target, extension)
  hash = Digest::MD5.file(file).hexdigest
  hash = Digest::MD5.hexdigest(hash.to_s + target)
  filename = "#{hash}.#{extension}"
  dest = File.join(path, filename)

  if File.exist?(dest)
    puts "Skipping"
    return filename
  end

  puts "Writing #{dest}"
  # Resize image and write it to destination
  image = MiniMagick::Image.open(file)
  image.resize(target)
  image.format(extension)
  image.write(dest)

  return filename
end

def forImgs(imgs, &block)
  if imgs.respond_to?("each")
    imgs.each &block
  else
    block.call(imgs)
  end
end

def placeImage(file, src, href = nil)
  if href
    file.puts "<a href=\"#{href}\">"
  end
  file.puts "<img src=\"#{src}\">"
  if href
    file.puts "</a>"
  end
end

options = {}
OptionParser.new do |opts|
  opts.banner = "Usage: build.rb dest"

  opts.on("-d", "--dest PATH", "PATH to put build files") do |path|
    options[:path] = path
  end
  opts.on("-s", "--size SIZE", "Size to resize images to") do |size|
    options[:size] = size
  end
  opts.on("-g", "--commit HASH", "Commit to display on website") do |hash|
    options[:commit] = hash
  end
  opts.on("-c", "--clean", "Cleanup unused images") do |v|
    options[:clean] = true
  end
  opts.on("-b", "--linkbase URL", "Add links to images, with URL as base") do |url|
    options[:base] = url
  end
  opts.on("-e", "--extension EXT", "Image extension to use with imagemagick") do |ext|
    options[:extension] = ext
  end
end.parse!

options[:path] = "build" unless options[:path]
options[:size] = "1920x1080" unless options[:size]
options[:clean] = false unless options[:clean]
options[:extension] = "jpg" unless options[:extension]
puts options

# Create build dir
FileUtils.mkdir_p(options[:path])

defs = YAML.load(File.read("imginfo.yml"))
files = {}

puts defs

defs["groups"].each do |value|

  # For each image inside group
  forImgs(value["imgs"]) do |img|
    puts "Converting file #{img}"
    dest = copyimage(options[:path], img, options[:size], options[:extension])
    files[img] = dest
  end

end

puts files

template = File.read("index.tmpl")
template = template.split("%BODY%")

# Cleanup old files
if options[:clean]
  Dir.glob(File.join(options[:path], "*")) do |file|
    hash = File.basename(file)
    if !files.values.include? hash 
      puts "Cleaning #{hash}"
      File.delete(file)
    end
  end
end

File.open(File.join(options[:path], "index.html"), "w") do |file|
  # Print preample
  file.write(template[0])

  defs["groups"].each do |value|
    file.puts "<div class=\"group\">"
    if value[:title]
      file.puts "<h2>#{value[:title]}</h2>"
    end
    forImgs(value["imgs"]) do |img|
      href = options[:base]
      # If href is given add a filename at the end
      if href
        href = File.join(href, img)
      end

      placeImage(file, files[img], href)
    end

    if value["what"]
      file.puts "<p>#{value["what"]}"
    end
    file.puts "</div>"
  end

  if options[:commit]
    file.puts "<p>Build from commit #{options[:commit]}</p>"
  end

  # Print postampleee?
  file.write(template[1])
end