"""
mail.Reader
mail.Writer
"""

import os.path as opath
from os.path import getctime
import re
import time
from datetime import datetime
from PIL import Image
from math import ceil
import sys
import md5
import base64
import sys

class FileDoesNotExist(Exception):
	def __init__(self, fname):
		self.filename = fname
	def __str__(self):
		return '%s does not exist'%(self.filename)
		
class NoDate(Exception):
	def __init__(self, fname):
		self.filename = fname
	def __str__(self):
		return '%s does not provide any date info'%(self.filename)

class Reader:
	def __init__(self, filename, root = False):
		self.type = 'image'
		if root <> False:
			filename = opath.join (root, filename)
		if not opath.exists(filename):
			raise FileDoesNotExist(filename)
		try:
			im = Image.open (filename)
		except IOError:
			print 'Cannot open %s: expect missing data'%(filename,)
		except Exception as e:
			print 'Unhandle exception: %s'%(e,)

		self.img = {}
		self.img['filename'] = filename
		#self.creationtime = self.get_creationtime (im)
		self.img['date'] = self.get_creationtime_from_filename (filename)
		self.img['fullpage'] = self.is_fullpage ()
		self.img['type'] = 'image'

	def get_creationtime_from_filename (self, filename):
		tail = opath.split (filename)[1]
		date_patt = '(\d{4})(\d{2})(\d{2})_(\d{2})h(\d{2})m(\d{2})s'
		alt_date_patt = '(\d{4})(\d{2})(\d{2})'
		d = re.search (date_patt, tail)
		if d <> None:
			# Regular date time is in the filename
			return datetime (int (d.group(1)), int (d.group(2)), int(d.group(3)), int(d.group (4)), int(d.group (5)), int(d.group(6)))
		else:
			d = re.search (alt_date_patt, tail)
			if d <> None:
				# We've found somewhat of a date in the filename. Try to parse it.
				try:
					return datetime (int (d.group(1)), int (d.group(2)), int(d.group(3)), 0, 0, 0)
				except ValueError:
					# Fallback to the date in the directory
					return self.get_creationtime_from_path (filename)
			else:
				# Fallback to the date in the directory
				return self.get_creationtime_from_path (filename)
	
	def get_creationtime_from_path(self, filename):
		parts = filename.split ('/')
		parts.reverse()
		
		for part in parts:
			d = re.search ('(\d{4})-(\d{2})-(\d{2})', part)
			if d <> None:
				try:
					return datetime (int (d.group(1)), int (d.group(2)), int(d.group(3)), 0, 0, 0)
				except ValueError:
					# Fallback to the date in the directory
					continue
		
		raise NoDate (filename)
	
	def is_fullpage (self):
		return re.search ('FULL', opath.split (self.img['filename'])[1]) <> None

	def get_creationtime(self, im):
		exif = im._getexif();
		ctime = datetime.fromtimestamp (getctime (self.img['filename'] ))

		if exif <> None:
			for field in [306,36868,36867]:
				if field in exif:
					new_time = datetime.strptime (exif[field], '%Y:%m:%d %H:%M:%S')
					if new_time <> None and (ctime == None or (time.mktime (new_time.timetuple()) > 0 and new_time < ctime)):
						ctime = new_time	

		return ctime
		
class Writer:
	panel_count = 4
	tex_special_chars = {r'&': '\\&', r'%': '\\%', r'$': '\\$', r'#': '\\#', r'_': '\\_', r'{': '\\{', r'}': '\\}', r'~': '\\textasciitilde{}', r'^': '\\textasciicircum{}', '\\' : '\\textbackslash{}', '|':'\\textbar{}'}
	def __init__(self, reader):
		self.image = reader

	def as_string(self, width='\\getvariable{pageprops}{columnwidth}', place='here', caption='none'):
		et_pat = '[%s]'%(re.escape(''.join(self.tex_special_chars.keys())),)
		buff = ''
		if (self.fullpage == True):
			paths = self.splitImage ()
			buff += '\n\\page'
			#buff += '\n\\setuplayout[width=\paperwidth,textheight=\paperheight,rightedge=0mm,rightmargin=0mm,leftmargin=0mm,leftedge=0mm,top=0mm,header=0mm,footer=0mm,bottom=0mm,backspace=0mm,topspace=0mm,rightedgedistance=0mm,rightmargindistance=0mm,leftmargindistance=0mm,leftedgedistance=0mm,topdistance=0mm,footerdistance=0mm,bottomdistance=0mm]'
			buff += '\n\\setuplayout[nomargins]'
			for path in paths:
				buff += '\n\\placefigure[here,force]{none}{\\externalfigure[%s][width=\\paperwidth,height=\\paperheight]}'%(re.sub(et_pat, getattr(self, 'escape_tex'), path))
			buff += '\n\\page'
			buff += '\n\\setuplayout[reset]'

		else:
			esc_text = re.sub(et_pat, getattr(self, 'escape_tex') , self.filename)
			imgpts = [esc_text]
			md = md5.new()
			md.update(esc_text)
			mds = base64.b64encode(md.digest())
			
			options = []
			if width <> False:
				options.append ('width=%s' % width)
				options.append ('factor=max')
			try:
				buff += '\\useexternalfigure[%s][%s]'%(mds,esc_text)
				buff += '\\medskip\\hbox {\\externalfigure[%s][%s]}' % (mds, ','.join(options))
				buff += '\\blank[image]'
			except Exception as e:
				pass

		return buff


	def escape_tex(self, pt):
		r = pt.group()
		if r in self.tex_special_chars:
			return self.tex_special_chars[r]
		return r


	def __getattr__(self, name):
		try:
			return self.image[name]
		except Exception:
			raise AttributeError(name)

	def splitImage (self):
		tmp_path = '/tmp/OSP_AETHER9__'
		im = Image.open (self.filename)
		panelWidth = int (ceil (float(im.size[0]) * (1.0 / float (self.panel_count))))
		part = opath.split(self.filename)[1].split ('.')[0]
		paths = []
		for i in range (0,self.panel_count):
			panel = Image.new (im.mode, (panelWidth, im.size[1]), (255,255,255))
			panel.paste (im.copy (), (i * -panelWidth,0))
			paths.append ('%s%s_%d.png' % (tmp_path, part, i))
			panel.save (paths[-1])
		
		return paths

if __name__ == '__main__':
	from glob import glob

	root = '/home/gijs/Documents/osp/osp.work.aether9'

	for filename in glob (opath.join (root, 'PAR-PERFO/*/img/*.jpg')):
		reader = Reader (filename)
		if reader.img['date'] <> None or reader.img['fullpage'] == True:
			writer = Writer (reader)
			print writer.as_string ()