asset_information.rb in emojidex-0.2.0

- old
+ new

@@ -1,12 +1,13 @@
+require 'digest/md5'
 require_relative '../../defaults'
 
 module Emojidex
   module Data
     # Asset information for emoji
     module EmojiAssetInformation
-      attr_accessor :checksums, :paths
+      attr_accessor :checksums, :paths, :local_checksums
 
       def init_asset_info(details)
         blank_checksums
         fill_checksums(details[:checksums]) if details.include? :checksums
       end
@@ -23,23 +24,105 @@
         @checksums[:svg] = nil
         @checksums[:png] = {}
         Emojidex::Defaults.sizes.keys.each do |size|
           @checksums[:png][size] = nil
         end
+        @local_checksums = @checksums.dup
       end
 
       def fill_checksums(checksums)
         @checksums[:svg] = checksums[:svg] if checksums.include? :svg
         return unless checksums.include? :png
         Emojidex::Defaults.sizes.keys.each do |size|
           @checksums[:png][size] = checksums[:png][size] if checksums[:png].include? size
         end
       end
 
+      def fill_paths(paths)
+        @paths[:svg] = paths[:svg] if paths.include? :svg
+        return unless paths.include? :png
+        Emojidex::Defaults.sizes.keys.each do |size|
+          @paths[:png][size] = paths[:png][size] if paths[:png].include? size
+        end
+      end
+
+      # Acquires path and caches the target file if not found or out of date
+      def path(format, size = nil)
+        fp = path?(format, size)
+        cache(format, [size]) unless !fp.nil? && File.exist?(fp)
+        fp
+      end
+
       # returns asset path
       def path?(format, size = nil)
-        return @paths[format][size] unless size.nil?
-        @paths[format]
+        case format
+        when :svg
+          return @paths[format] if File.exist?(@paths[format])
+        when :png
+          return nil if size.nil?
+          return @paths[format][size] if File.exist?(@paths[format][size])
+        end
+        nil
+      end
+
+      # Caches a file of the specified format in the specified sizes
+      def cache(format, sizes = nil)
+        generate_local_checksums
+        case format
+        when :png
+          _cache_png(sizes) unless sizes.nil?
+        when :svg
+          _cache_svg
+        end
+      end
+
+      # Generates a checksum for each locally cached file
+      def generate_local_checksum(format, size = nil)
+        case format
+        when :png
+          return @local_checksums[:png][size] = _checksum_for_file(@paths[:png][size])
+        when :svg
+          return @local_checksum[:svg] = _checksum_for_file(@paths[:svg])
+        end
+        nil
+      end
+
+      def generate_local_checksums
+        @local_checksums[:svg] = _checksum_for_file(@paths[:svg])
+        @paths[:png].keys.each do |size|
+          @local_checksums[:png][size] = _checksum_for_file(@paths[:png][size])
+        end
+        @local_checksums
+      end
+
+      private
+
+      def _cache_svg
+        @paths[:svg] = Dir.pwd unless (@paths.include? :svg) && !@paths[:svg].nil?
+        return if File.exist?(@paths[:svg]) && !@checksums[:svg].nil? &&
+                  @checksums[:svg] == generate_local_checksum(:svg)
+        response = Emojidex::Service::Transactor.download("#{@code}.svg")
+        File.open(@paths[:svg], 'wb') { |fp| fp.write(response.body) }
+        generate_local_checksum(:svg)
+      end
+
+      def _cache_png(sizes)
+        sizes.each do |size|
+          unless @paths.include?(:png) &&
+                 @paths[:png].include?(size) && @paths[:png][size].nil? == false
+            @paths[:png][size] = "#{Dir.pwd}/#{size}/#{@code}.png"
+          end
+          next if File.exist?(@paths[:png][size]) &&
+                  !@checksums[:png][size].nil? &&
+                  @checksums[:png][size] == generate_local_checksum(:png, size)
+          response = Emojidex::Service::Transactor.download("#{size}/#{@code}.png")
+          File.open(@paths[:png][size], 'wb') { |fp| fp.write(response.body) }
+          generate_local_checksum(:png, size)
+        end
+      end
+
+      def _checksum_for_file(path)
+        (File.exist? path) ? Digest::MD5.file(path).hexdigest : nil
       end
     end
   end
 end