import json, os, logging
import xml.etree.ElementTree as et
import export.utils
import config
from datetime import datetime

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 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']

	content = et.SubElement(mail, 'content')
	content.text = export.utils.format_content(msg['content'])

	# 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 = 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)

	fout.write(export.utils.remove_invalid_xml_characters(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, 'w') 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, 'w') 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')))