import json, os, logging
import xml.etree.ElementTree as et
from xml.sax.saxutils import unescape, escape
import export.utils
import config
from datetime import datetime
from export import emailreply
import re

nn = 0

sel_dump = os.path.join(config.selection['path'], config.selection['sel_dump'])
xml_dump = os.path.join(config.export['path'], config.export['xml'])


def export_generate_path(tag):
	now = datetime.now()
	return os.path.join(config.export['path'], tag + "_[now].xml")

def make_xml_element(el, val):
	return "<" + el + ">" + escape(val) + "</" + el + ">"


def emit_mail_xml(msg, li):

	global nn
	nn += 1

	logging.info("export xml: " + li)

	subject = make_xml_element("subject", msg['subject']) + "\n"

	if 'to' in msg: 
		to = make_xml_element("to", msg['to']) + "\n"
	else:
		to = make_xml_element("to", 'n/a') + "\n"

	from_ = make_xml_element("from", msg['from']) + "\n"

	date = make_xml_element("date", msg['date']) + "\n"

	'''
	todo:
		- filter reply 
		- unescape XML
	'''
	e = emailreply.EmailMessage(export.utils.format_content(msg['content']))
	e.read()

	content_stripped = re.sub(r'(?<!\n)\n(?!\n)', ' ', e.reply)

	content = make_xml_element("content", content_stripped) + "\n"

	mail = "<mail>\n" + subject + from_ + to + date + content + "</mail>\n"

	# content = et.SubElement(mail, 'content')
	# content.text = e.reply

	# recursuve "follow-up"
	if 'follow-up' in msg:
		followups = export.utils.index_follow_up(msg)
		followups.sort(key=lambda tup: tup[0])
		for d, f in followups:
			mail += emit_mail_xml(f, li)

	return mail


# def emit_mail_xml(msg, li, xmlel):

# 	global nn
# 	nn += 1

# 	logging.info("export xml: " + li)

# 	mail = et.SubElement(xmlel, 'mail')

# 	subject = et.SubElement(mail, 'subject')
# 	subject.text = export.utils.format_subject(msg['subject'])

# 	to = et.SubElement(mail, 'to')
# 	if 'to' in msg: 
# 		to.text = msg['to']
# 	else:
# 		to.text = 'n/a'

# 	from_ = et.SubElement(mail, 'from')
# 	from_.text = msg['from']

# 	date = et.SubElement(mail, 'date')
# 	date.text = msg['date']

# 	'''
# 	todo:
# 		- filter reply 
# 		- unescape XML
# 	'''
# 	e = emailreply.EmailMessage(export.utils.format_content(msg['content']))
# 	e.read()

# 	escape_table = {
# 		"&": "&amp;",
# 		">": "&gt;",
# 		"<": "&lt;"
# 	}

# 	content_str = "<content>" + escape(e.reply, escape_table) + "</content>"

# 	print(content_str)

# 	content = et.fromstring(content_str)
# 	mail.append(content)

# 	# content = et.SubElement(mail, 'content')
# 	# content.text = e.reply

# 	# recursuve "follow-up"
# 	if 'follow-up' in msg:
# 		followups = export.utils.index_follow_up(msg)
# 		followups.sort(key=lambda tup: tup[0])
# 		for d, f in followups:
# 			emit_mail_xml(f, li, xmlel)


#------------------------------------------------------------
# The following functions parse the selection files 
#------------------------------------------------------------

def export_single_tag(t, sel, fout):

	if t not in list(sel.keys()):
		logging.error("Tag: " + t + " does not exists.")
		return False

	ch = sel[t]


	chapter = "<chapter>\n"

	chapter_title = make_xml_element("title", t) + "\n"

	chapter_desc = make_xml_element("desc", ch['desc']) + "\n"

	chapter_mails = "<mails>\n"

	for m in ch['lists']:
		chapter_mails += emit_mail_xml(m, m['list'])

	chapter_mails += "</mails>\n"

	chapter = "<chapter>\n" + chapter_mails + "</chapter>"

	fout.write(chapter.encode('utf-8'))


	# # root = et.ElementTree(chapter)
	# # root.write(fout, encoding="utf-8", xml_declaration=True)

	# # xml = export.utils.remove_invalid_xml_characters(et.tostring(chapter).decode('unicode-escape', 'ignore'))
	# xml = export.utils.remove_invalid_xml_characters(et.tostring(chapter, encoding="utf-8").decode('utf-8', 'ignore'))
	# xml = '<?xml version="1.0" encoding="UTF-8"?>' + xml

	# print(et.tostring(chapter, encoding="utf-8").decode('utf-8', 'ignore'))

	# fout.write(et.tostring(chapter).decode('utf-8', 'ignore'))

	return True


# def export_single_tag(t, sel, fout):

# 	if t not in list(sel.keys()):
# 		logging.error("Tag: " + t + " does not exists.")
# 		return False

# 	ch = sel[t]

# 	chapter = et.Element('chapter')
# 	chapter_title = et.SubElement(chapter, 'title')
# 	chapter_title.text = t

# 	chapter_desc = et.SubElement(chapter, 'desc')
# 	chapter_desc.text = ch['desc']

# 	chapter_mails = et.SubElement(chapter, 'mails')

# 	for m in ch['lists']:
# 		emit_mail_xml(m, m['list'], chapter_mails)


# 	# root = et.ElementTree(chapter)
# 	# root.write(fout, encoding="utf-8", xml_declaration=True)

# 	# xml = export.utils.remove_invalid_xml_characters(et.tostring(chapter).decode('unicode-escape', 'ignore'))
# 	xml = export.utils.remove_invalid_xml_characters(et.tostring(chapter, encoding="utf-8").decode('utf-8', 'ignore'))
# 	xml = '<?xml version="1.0" encoding="UTF-8"?>' + xml

# 	print(et.tostring(chapter, encoding="utf-8").decode('utf-8', 'ignore'))

# 	fout.write(et.tostring(chapter).decode('utf-8', 'ignore'))

# 	return True

def export_selection_all(sel_dump=sel_dump, xml_out=xml_dump):

	with open(sel_dump) as fin:
		d = json.load(fin)

	with open(xml_dump, 'wb') as fout:
		for k in d.keys():
			if not export_single_tag(k, d, fout):
				logging.error("Error exporting: " + k)
				return False
	return True

def export_selection_tag(tag, sel_dump=sel_dump, xml_out=xml_dump):

	with open(sel_dump) as fin:
		d = json.load(fin)

	now = datetime.now()
	xml_out.replace("[now]", now.strftime("%d-%m-%y_%H:%M:%S"))

	with open(xml_out, 'wb') as fout:
		if not export_single_tag(tag, d, fout):
			logging.error("Error exporting: " + tag)
			return False
	return True



#------------------------------------------------------------
# The following functions parse the archive files directly
#------------------------------------------------------------

def export_file(f, fout):

	with open(f) as fp:
		d = json.load(fp)

	all_mail = et.Element('all')
	for t in d['threads']:
		emit_mail_xml(t, all_mail)		

	fout.write(et.tostring(all_mail).decode('utf-8', 'ignore'))		

def parse_date_file(fname):
	return datetime.strptime(fname, '%B_%Y.json')

def export_year(d, dt, fout):

	dir_files = [f for f in glob.glob(os.path.join(d, "*.json"))]

	chapter = et.Element('chapter')
	year = et.SubElement(chapter, 'year')
	year.text = dt.strftime('%Y')

	# SORT MONTHS BEFORE WRITING TO XML
	dates = []
	for f in dir_files:

		fdt = parse_date_file(os.path.basename(f))
		if dt.year != fdt.year:
			continue

		dates.append((fdt, f))

	dates.sort(key=lambda tup: tup[0])

	for d, f in dates:

		logging.debug(f)

		section = et.SubElement(chapter, 'section')
		month = et.SubElement(section, 'month')
		month.text = d.strftime('%B')

		with open(f) as fp:
			dj = json.load(fp)

		mails = et.SubElement(section, 'mails')
		for t in dj['threads']:
			emit_mail_xml(t, mails)		

	# write utf8 to file (et.tostring are bytes)
	# fout.write(et.tostring(chapter).decode('utf-8', 'ignore'))
	fout.write(export.utils.remove_invalid_xml_characters(et.tostring(chapter).decode('utf-8', 'ignore')))