#!/usr/bin/env python

'''
mm extern webresize.py
Use extern imagemagick binary to downscale the image.

Author:
Michael Munzert (mail mm-log com)

Version:
2010.02.03 Added different filters.

modelled after the trace plugin (lloyd konneker, lkk, bootch at nc.rr.com) 

License:

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.

The GNU Public License is available at
http://www.gnu.org/copyleft/gpl.html

'''

from gimpfu import *
import subprocess
import os

def plugin_main(image, drawable, size, method, visible):
  # Get image file name
  name = image.filename
  
  # Get exif data
  exifdata = image.parasite_find("exif-data")

  # Copy so the save operations doesn't affect the original
  tempimage = pdb.gimp_image_duplicate(image)
  if not tempimage:
    raise RuntimeError
    
  # Use temp file names from gimp, it reflects the user's choices in gimp.rc
  tempfilename = pdb.gimp_temp_name("tif")
  if visible == 0:  
    # Save in temporary.  Note: empty user entered file name
    tempdrawable = pdb.gimp_image_get_active_drawable(tempimage)
  else:
    # Get the current visible
    tempdrawable = pdb.gimp_layer_new_from_visible(image, tempimage, "visible") 

  # !!! Note no run-mode first parameter, and user entered filename is empty string
  pdb.gimp_progress_set_text ("Saving a copy")
  pdb.gimp_file_save(tempimage, tempdrawable, tempfilename, "")

  width = tempdrawable.width
  height = tempdrawable.height
  
  # Command string for mogrify.
  if method == 1:
    arg = "-filter Catrom "
  elif method == 2:
    arg = "-filter Mitchell "
  elif method == 3:
    arg = "-filter Cubic "
  else:
    arg = "-filter Lanczos "
  
  if height > width:
    arg = arg + "-resize x" + str(size) + " "
  else :
    arg = arg + "-resize " + str(size) + " "

  # Command line for linux
  command = "/usr/bin/mogrify " + arg + "\"" + tempfilename + "\""
  # Command line for windows, alter path if needed
  # command = "c:\\programs\\ImageMagick\\mogrify.exe " + arg + "\"" + tempfilename + "\""

  # Invoke mogrify.

  pdb.gimp_progress_set_text ("Resizing")
  pdb.gimp_progress_pulse()
  child = subprocess.Popen(command, shell=True)
  child.communicate() 

  # Reload the transformed image.

  try: 
    newimage = pdb.file_tiff_load(tempfilename, "")
  except: 
    RuntimeError

  # Write exif data
  if exifdata != None:  
    newimage.parasite_attach(exifdata)

  # Write name
  if name != None:
    newimage.filename = name

  '''
  # just for testing, put it as a new layer in the opened image
  try:
    newlayer = pdb.gimp_file_load_layer(image, tempfilename)
  except:
    RuntimeError
  image.add_layer(newlayer,0)
  '''

  # cleanup
  os.remove(tempfilename)  # delete the temporary file
  gimp.delete(tempimage)   # delete the temporary image
  
  # Note the new image is dirty in Gimp and the user will be asked to save before closing.

  gimp.Display(newimage)
  gimp.displays_flush()


  
register(
        "python_fu_mm_extern_webresize",
        "Create a new resized image by using the Lanczos algorithm of ImageMagick. Requires separate ImageMagick (mogrify) program to be installed.",
        "Create a new resized image by using the Lanczos algorithm of ImageMagick. Requires separate ImageMagick (mogrify) program to be installed.",
        "Michael Munzert (mail mm-log com)",
        "Copyright 2010 Michael Munzert",
        "2010",
        "<Image>/Filters/MM-Filters/_Web Resize ...", # menuitem with accelerator key
        "*", # image types
        [ (PF_SPINNER, "size", "Longer edge:", 800, (400, 2000, 100)),
          (PF_OPTION, "method", "Filter:", 0, ["Lanczos","Catrom","Mitchell","Cubic"]),
          (PF_RADIO, "visible", "Layer:", 1, (("new from visible", 1),("current layer",0)))
        ],
        [],
        plugin_main,
        # menu="<Image>/Filters", # really the menupath less menuitem. 
        # Enables plugin regardless of image open, passes less params
        # domain=("gimp20-python", gimp.locale_directory))
        )

main()