require "FlickrCollage/version"
require "methadone"
require "flickraw"
require "mini_magick"
require "open-uri"
require "fileutils"

# Creating collage from top-rated Flickr images for your keywords
# @author Chromium
module FlickrCollage
  # Class for Dictionary. Provides random words
  IMG_COUNT     = 10
  IMG_PATH      = "./"
  COLLAGE_FILE  = "flickrCollage"
  RAISE_ERROR   = true

  class Dictionary
    DICT_FILE = "/usr/share/dict/words"
    # @return [Array] All words at dictionary file
    attr_accessor :words

    def initialize(opts = {})
      opts[:file] ||= DICT_FILE
      @words = File.read(opts[:file]).lines.select do |line|
        (4..9).cover?(line.strip.size)
      end
    end

    # Get random word from Dictionary file
    #
    # @return [String] random word
    def get_word
      @words.sample.strip
    end
  end

  # Class for Flickr. Get and download top-rated images for keywords
  class Flickr
    include Methadone::CLILogging

    API_KEY         = "27ad23a09746546c02c79f39879ee408"
    SHARED_SECRET   = "707eaf92eece0744"
    SEARCH_KEYWORD  = "Giant Robots Smashing into Other Giant Robots"
    SEARCH_COUNT    = 1
    # @return [String] Path for saving images
    attr_accessor :img_path

    def initialize(opts = {})
      opts[:api_key]        ||= API_KEY
      opts[:shared_secret]  ||= SHARED_SECRET
      opts[:img_path]       ||= IMG_PATH

      FlickRaw.api_key        = opts[:api_key]
      FlickRaw.shared_secret  = opts[:shared_secret]
      @img_path               = opts[:img_path]
    end

    # Search top-rated images for keyword
    #
    # @param [Hash] opts
    # @option opts [String] :keyword ('Giant Robots Smashing into Other Giant Robots') keyword for search
    # @option opts [Number] :count (1) how many images you need
    #
    # @return [Array<String>] urls with top-rated images for keyword
    # @return [String] url with top-rated image for keyword
    def search(opts = {})
      opts[:keyword]  ||= SEARCH_KEYWORD
      opts[:count]    ||= SEARCH_COUNT
      photos = []
      begin
        list = flickr.photos.search(text: opts[:keyword], sort: "interestingness-desc", per_page: opts[:count])
        debug "flickr.search: #{opts[:keyword]} (img: #{list.size})"

        list.each do |photo|
          info = flickr.photos.getInfo(photo_id: photo.id)
          debug "flickr.search: get image url for #{photo.id}"
          # debug "flickr.search: #{FlickRaw.url_photopage(info)}"
          photos << FlickRaw.url_c(info)
        end
      rescue StandardError => e
        warn "flickr.search: caught exception #{e}"
        raise e if RAISE_ERROR
      end
      photos.size > 1 ? photos : photos.first
    end

    # Download images from urls
    #
    # @param [Array<Hash>] opts
    # @option opts [String] :keyword keyword for file name
    # @option opts [String] :url image url
    #
    # @return [Array<String>] files paths for downloaded images
    # @return [String] file path for downloaded image
    def download(opts = {})
      opts ||= []
      photos = []
      return photos unless opts.any?
      opts = [keyword: opts[:keyword], url: opts[:url]] unless opts.is_a?(Array)
      FileUtils.mkdir_p("#{@img_path}tmp")

      begin
        opts.each do |img|
          debug "flickr.download: #{img[:keyword]} #{img[:url]}"
          next unless defined?(img[:url]) && !img[:url].nil?
          open(img[:url]) do |url|
            File.open("#{@img_path}tmp/#{img[:keyword]}.jpg", "wb") do |file|
              file.puts url.read
            end
            file = "#{@img_path}tmp/#{img[:keyword]}.jpg"
            debug "flickr.download: file #{file}"
            photos << file if Image.valid?(file)
          end
        end
      rescue StandardError => e
        warn "flickr.download: caught exception: #{e.inspect}"
        raise e if RAISE_ERROR
      end
      photos.size > 1 ? photos : photos.first
    end

    # Scrape top-rated images for keyword
    #
    # @param [Hash] opts
    # @option opts [String] :keyword ('Giant Robots Smashing into Other Giant Robots') keyword for scrape
    #
    # @return [String] file path for downloaded image
    def scrape(opts = {})
      opts[:keyword] ||= SEARCH_KEYWORD

      url = search(keyword: opts[:keyword])
      debug "flickr.scrape: #{opts[:keyword]} #{url}"
      download(keyword: opts[:keyword], url: url)
    end
  end

  # Class for Image. Create collage and crop images
  # @attr_reader [String] img_path Path for saving images
  # @attr_reader [Number] img_width Width for images crop
  # @attr_reader [Number] img_height Height for images crop
  # @attr_reader [String] collage_file Collage file name
  # @attr_reader [Boolean] clear_tmp Delete all downloaded images
  class Image
    include Methadone::CLILogging

    IMG_WIDTH   = 800
    IMG_HEIGHT  = 600

    attr_accessor :img_path, :img_width, :img_height, :collage_file, :clear_tmp

    def initialize(opts = {})
      opts[:img_path]     ||= IMG_PATH
      opts[:img_width]    ||= IMG_WIDTH
      opts[:img_height]   ||= IMG_HEIGHT
      opts[:collage_file] ||= COLLAGE_FILE

      @img_path           = opts[:img_path]
      @img_width          = opts[:img_width]
      @img_height         = opts[:img_height]
      @collage_file       = opts[:collage_file]
      @clear_tmp          = opts[:clear_tmp]
    end

    # Validates downloaded image
    #
    # @param [String] file file path for downloaded image
    #
    # @return [true] image is valid
    # @return [false] image is not valid
    def self.valid?(file)
      return false if file.nil?
      begin
        image = MiniMagick::Image.open(file)
      rescue StandardError => e
        warn "Image.valid: caught exception #{e}"
        raise e if RAISE_ERROR
      end
      image.valid?
    end

    # Resize image
    #
    # @param [Hash] opts
    # @option opts [String] :file file path for image
    # @option opts [Number] :width (@img_width) image new width
    # @option opts [Number] :height (@img_height) image new height
    #
    # @return [String] file path for resized image
    def resize(opts = {})
      return false if opts[:file].nil?

      opts[:width]    ||= @img_width
      opts[:height]   ||= @img_height
      begin
        image = MiniMagick::Image.open(opts[:file])
        resize_to_fill(opts[:width], opts[:height], image)
        file_resize = "#{@img_path}tmp/#{File.basename(opts[:file], ".jpg")}_resize.jpg"
        image.write file_resize
        debug "Resize #{opts[:file]} to #{opts[:width]}x#{opts[:height]}"
      rescue StandardError => e
        warn "Image.resize: caught exception #{e}"
        raise e if RAISE_ERROR
      end
      file_resize
    end

    # Creates collage from 10 images
    #
    # @param [Hash] opts
    # @option opts [Array<String>] :files file paths for collage images
    #
    # @return [true] collage created successfully
    # @return [false] something went wrong
    def collage(opts = {})
      unless opts[:files].size == IMG_COUNT
        info "Not enough images for collage"
        return false
      end

      begin
        (1..4).each do |row|
          montage = MiniMagick::Tool::Montage.new
          files = montage_resize(files: opts[:files], row: row)
          files.each do |file|
            montage << file
          end
          montage << "-mode"
          montage << "Concatenate"
          montage << "-background"
          montage << "none"
          montage << "-geometry"
          montage << montage_geometry(row: row)
          montage << "-tile"
          montage << montage_tile(row: row)
          montage << montage_img_path(row: row)
          montage.call
        end
      rescue StandardError => e
        warn "Image.collage: caught exception #{e}"
        raise e if RAISE_ERROR
      end
      FileUtils.rm_rf("#{@img_path}tmp") if @clear_tmp
      true
    end

    # Smart image crop
    #
    # @param [Number] width image new width
    # @param [Number] height image new height
    # @param [MiniMagick::Image] img image
    # @param [String] gravity crop around
    #
    # @return [MiniMagick::Image] cropped image
    def resize_to_fill(width, height, img, gravity = "Center")
      cols, rows = img[:dimensions]
      img.combine_options do |cmd|
        if width != cols || height != rows
          scale_x = width / cols.to_f
          scale_y = height / rows.to_f
          if scale_x >= scale_y
            cols = (scale_x * (cols + 0.5)).round
            rows = (scale_x * (rows + 0.5)).round
            cmd.resize cols.to_s
          else
            cols = (scale_y * (cols + 0.5)).round
            rows = (scale_y * (rows + 0.5)).round
            cmd.resize "x#{rows}"
          end
        end

        cmd.gravity gravity
        cmd.background "rgba(255,255,255,0.0)"
        cmd.extent "#{width}x#{height}" if cols != width || rows != height
      end
    end

    # Creates simple collage 5x2 from 10 images
    #
    # @param [Hash] opts
    # @option opts [Array<String>] :files file paths for collage images
    #
    # @return [true] collage created successfully
    # @return [false] something went wrong
    # @deprecated First collage implementation
    def collage_simple(opts = {})
      unless opts[:files].size == IMG_COUNT
        info "No images for collage"
        return false
      end

      begin
        montage = MiniMagick::Tool::Montage.new
        opts[:files].each do |file|
          montage << resize(file: file)
        end
        montage << "-mode"
        montage << "Concatenate"
        montage << "-background"
        montage << "none"
        montage << "-geometry"
        montage << "#{@img_width}x#{@img_height}+0+0"
        montage << "-tile"
        montage << "5x2"
        montage << "#{@img_path}#{@collage_file}.jpg"
        puts montage.inspect.to_s
        montage.call
      rescue StandardError => e
        warn "Image.collage: caught exception #{e}"
        raise e if RAISE_ERROR
      end
      true
    end

    private

    # Montage Collage - resizing images for rows
    # 1 row - 3 images
    # 2 row - 4 images
    # 3 row - 3 images
    #
    # @param [Hash] opts
    # @option opts [Number] :row collage row 1..4 (4 row - final collage from first 3 rows)
    #
    # @return [Array<String>] Array of file paths for resized images
    def montage_resize(opts = {})
      files = []
      case opts[:row]
      when 1
        (0..2).each do |i|
          files << resize(file: opts[:files][i])
        end
      when 2
        (3..6).each do |i|
          files << resize(file: opts[:files][i], width: @img_width * 0.75)
        end
      when 3
        (7..9).each do |i|
          files << resize(file: opts[:files][i])
        end
      when 4
        (1..3).each do |i|
          files << "#{@img_path}tmp/#{@collage_file}-#{i}.jpg"
        end
      end
      files
    end

    # Montage Collage - setting images geometry for rows
    # 1 row - 3 images
    # 2 row - 4 images
    # 3 row - 3 images
    #
    # @param [Hash] opts
    # @option opts [Number] :row collage row 1..4 (4 row - final collage from first 3 rows)
    #
    # @return [String] images geometry
    def montage_geometry(opts = {})
      case opts[:row]
      when 1, 3 then "#{@img_width}x#{@img_height}+0+0"
      when 2 then "#{@img_width * 0.75}x#{@img_height}+0+0"
      when 4 then "#{@img_width * 3}x#{@img_height}+0+0"
      end
    end

    # Montage Collage - setting images tile for rows
    # 1 row - 3 images
    # 2 row - 4 images
    # 3 row - 3 images
    #
    # @param [Hash] opts
    # @option opts [Number] :row collage row 1..4 (4 row - final collage from first 3 rows)
    #
    # @return [String] images tile
    def montage_tile(opts = {})
      case opts[:row]
      when 1, 3 then "3x1"
      when 2 then "4x1"
      when 4 then "1x3"
      end
    end

    # Montage Collage - setting images paths for rows
    # 1 row - 3 images
    # 2 row - 4 images
    # 3 row - 3 images
    #
    # @param [Hash] opts
    # @option opts [Number] :row collage row 1..4 (4 row - final collage from first 3 rows)
    #
    # @return [String] images path
    def montage_img_path(opts = {})
      case opts[:row]
      when 1..3 then "#{@img_path}tmp/#{@collage_file}-#{opts[:row]}.jpg"
      when 4 then "#{@img_path}#{@collage_file}.jpg"
      else ""
      end
    end
  end
end