ShareImageComposerService

class ShareImageComposerService
  attr_reader :red_pack, :base, :avatar, :wxacode, :watchword

  def initialize(red_pack)
    @red_pack = red_pack
  end

  def perform
    set_material_images
    tempfile1 = base.composite(avatar) { |c| c.compose "Over"; c.geometry "+296+102" }
    tempfile2 = tempfile1.composite(wxacode) { |c| c.compose "Over"; c.geometry "+276+508" }
    tempfile2.combine_options{ |c| c.font "#{Rails.root}/vendor/assets/fonts/PingFang.ttc" ; c.encoding "UTF-8"; c.pointsize 40; c.fill 'white'; c.gravity "north"; c.draw "text 0,360 '#{watchword}'" }
    QiniuUploader.upload_file(ENVConfig.qiniu_domain, ENVConfig.qiniu_bucket, tempfile2).tap do
      [base, avatar, wxacode, tempfile1, tempfile2].each { |img| img.destroy! }
    end
  end

  private
    def wxacode_params
      {scene: "voice-redpack:#{red_pack.id}", page: "pages/voice_redpack/show", width: 246}
      # {scene: "voice-redpack:#{red_pack.id}", page: "pages/index/index", width: 246}
    end

    def set_material_images
      @base = MiniMagick::Image.open "#{Rails.root}/vendor/assets/images/voice-red-pack-share-base-image.jpg"
      @avatar = MiniMagick::Image.open "#{red_pack.user.avatar_url}?imageView2/0/w/160/h/160|roundPic/radius/!50p|imageslim"
      # @wxacode = set_wxacode_by_qiniu
      @wxacode = set_wxacode_by_minimagick
      @watchword = red_pack.watchword
    end

    def set_wxacode_by_qiniu
      wxacode_url = WeixinMiniProgramService.new(ENVConfig.weixin_oauth_app_id, ENVConfig.weixin_oauth_app_secret).create_wxacode_url(wxacode_params)
      MiniMagick::Image.open "#{wxacode_url}?imageView2/0/w/200/h/200|roundPic/radius/!50p"
    end

    def set_wxacode_by_minimagick
      original_wxacode_file = WeixinMiniProgramService.new(ENVConfig.weixin_oauth_app_id, ENVConfig.weixin_oauth_app_secret).create_wxacode_tempfile(wxacode_params)
      original_wxacode_image = MiniMagick::Image.open(original_wxacode_file.path).tap { original_wxacode_file.unlink }
      original_wxacode_image.resize "200x200"
      original_wxacode_image.format 'png'

      width = original_wxacode_image[:width]-2
      radius = width/2

      mask = ::MiniMagick::Image.open original_wxacode_image.path
      mask.format 'png'
      mask.combine_options do |m|
        m.alpha 'transparent'
        m.background 'none'
        m.fill 'white'
        m.draw 'roundrectangle 1,1,%s,%s,%s,%s' % [width, width, radius, radius]
      end

      overlay = ::MiniMagick::Image.open original_wxacode_image.path
      overlay.format 'png'
      overlay.combine_options do |o|
        o.alpha 'transparent'
        o.background 'none'
        o.fill 'none'
        o.stroke 'white'
        o.strokewidth 2
        o.draw 'roundrectangle 1,1,%s,%s,%s,%s' % [width, width, radius, radius]
      end

      masked = original_wxacode_image.composite(mask, 'png') do |i|
        i.alpha "set"
        i.compose 'DstIn'
      end
      original_wxacode_image.destroy!
      mask.destroy!

      result = masked.composite(overlay, 'png') do |i|
        i.compose 'Over'
      end
      masked.destroy!
      overlay.destroy!

      result
    end
end