$:.unshift(File.dirname(__FILE__)) unless
	$:.include?(File.dirname(__FILE__)) || $:.include?(File.expand_path(File.dirname(__FILE__)))


require 'PatchedPNG'

#generic class for a HI-RES picture

class AppleHiResPic<NativeFileType

#should be a subclass for each file system
  def self.file_system_file_types
    {}
  end
  
#colours cribbed from http://groups.google.com.au/group/comp.sys.apple2/browse_thread/thread/b9aa36ead6935c42/faa0f4df3e89060f
HGR_BLACK=PNG::Color::Black			#color=0,4
HGR_GREEN=PNG::Color.new(0x2F,0xB8,0x1F,0xFF)	#color=1
HGR_VIOLET=PNG::Color.new(0xC8,0x47,0xE4,0xFF)	#color=2
HGR_WHITE=PNG::Color::White			#color=3,7
HGR_ORANGE=PNG::Color.new(0xC7,0x70,0x28,0xFF)	#color=5
HGR_BLUE=PNG::Color.new(0x30,0x8F,0xE3,0xFF)	#color=6

HGR_COLS=40*7
HGR_ROWS=8*8*3


#per Apple // Reference Manual for //e chapter 2, pages 22-35
#also TechNote - Apple IIe #3 Double High-Resolution Graphics - http://web.pdx.edu/~heiss/technotes/aiie/tn.aiie.03.html
#HGR screen consists of 3 bands of 8 rows of 8 scanlines
#for each absolute scanline, what is the offset into screen ram that the 40 bytes for this scanline is stored?

@@scanline_offsets=Array.new(HGR_ROWS)

3.times do |band|
		8.times do |row|						
			8.times do |relative_scanline|
				band_ram_offset=band*40
				band_scanline_offset=band*64
				scanline_ram_offset=relative_scanline*1024
				scanline_scanline_offset=relative_scanline
				row_ram_offset=128*row
				row_scanline_offset=8*row
				scanline_offset=band_scanline_offset+scanline_scanline_offset+row_scanline_offset
				ram_offset=band_ram_offset+scanline_ram_offset+row_ram_offset								
				@@scanline_offsets[scanline_offset]=ram_offset
		end
	end
end


def self.matching_score
  [AppleBinary.matching_score+1,NADOLFile.matching_score+1].max
end

def to_picture
 buffer=unpacked_picture_bytes
  canvas = PNG::Canvas.new HGR_COLS, HGR_ROWS, PNG::Color::Black
  HGR_ROWS.times do |y|
    last_bit_set=false
    40.times do |x_byte|
      offset=@@scanline_offsets[y]+x_byte
      current_byte=buffer[offset]				
      current_byte=0 if current_byte.nil? #if we overrun the buffer then assume it's black
      7.times do |x_bit|
        x=x_byte*7+x_bit
        bit_set=((current_byte & (2**x_bit))>0)
        if (bit_set) then
          if (last_bit_set) then 
            #adjacent pixels should both be white
            AppleHiResPic.set_pixel(canvas,x-1,y,HGR_WHITE) 
            AppleHiResPic.set_pixel(canvas,x,y,HGR_WHITE)
          else
            if current_byte>=0x80 then
              pallete=[HGR_BLUE,HGR_ORANGE]
            else
              pallete=[HGR_VIOLET,HGR_GREEN]
            end
            this_pixel_colour=pallete[x%2]
            AppleHiResPic.set_pixel(canvas,x,y,this_pixel_colour)
            AppleHiResPic.set_pixel(canvas,x+1,y,this_pixel_colour) unless x>=HGR_COLS-1
          end
        end
        
        last_bit_set=bit_set
      end
    end
  end
  
  png = PNG.new canvas
  result=png.raw_bytes
  result
end

def picture_width
  HGR_COLS
end
def picture_height
  HGR_ROWS
end

def picture_format
  :png
end
private
	def self.set_pixel(canvas,x,y,colour)
				canvas[x, y]= colour
	end

end

class AppleDosPic < AppleHiResPic

  def self.file_system_file_types
    {
      AppleDos=>0x04
    }
  end

def self.load_address(contents)
  contents[0]+contents[1]*256
end

  def header_length
    4
  end
  def unpacked_picture_bytes
    data_without_header
  end 
  
  is_valid_file_if  lambda {  
      load_address=AppleBinary.load_address(contents)
     ((contents.length>=8184) && (contents.length<=9000) && ((load_address==0x2000) || load_address==0x4000))
  }
  
end

class NADOLPic < AppleHiResPic
  def self.file_system_file_types
    {
      NADOLDos=>:any
    }
  end
    is_valid_file_if  lambda {  
      (contents.length==8192)
    }
  def unpacked_picture_bytes
    contents
  end 
end

class PascalPic < AppleHiResPic
  def self.file_system_file_types
    {
      PascalDos=>0x07
    }
  end
  def unpacked_picture_bytes
    contents
  end 
end


class ProDosBinPic < AppleHiResPic
def self.file_system_file_types
  {
    ProDos=>0x06
  }
end
  
  is_valid_file_if  lambda {  
    (aux_code==0x2000 || aux_code==0x4000) && ((contents.length>=8192) && (contents.length<=9000)) || (aux_code==0x2000 && contents.length==0x4000)    
  }
  def unpacked_picture_bytes
    contents
  end 
  
  def load_address
    aux_code
  end
end




  
# == Author
# Jonno Downes (jonno@jamtronix.com)
#
# == Copyright
# Copyright (c) 2008 Jonno Downes (jonno@jamtronix.com)
#
#Permission is hereby granted, free of charge, to any person obtaining
#a copy of this software and associated documentation files (the
#"Software"), to deal in the Software without restriction, including
#without limitation the rights to use, copy, modify, merge, publish,
#distribute, sublicense, and/or sell copies of the Software, and to
#permit persons to whom the Software is furnished to do so, subject to
#the following conditions:

# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.

# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.