import sys, os, re, json
from datetime import datetime, date
import html2text
from escpos import printer
from PIL import Image
import base64
import io

def connect():
	# Get the printer's USB initializing code with $ sudo lsbusb
	try:
		# lp = printer.Usb(0x4b8,0xe15) # televex printer @ Varia
		lp = printer.Usb(0x4b8,0xe03) # printer @ poel
	except:
		lp = None

	return lp

def database(db_path):
	if not os.path.exists(db_path):
		with open(db_path, 'w') as f:
			f.write(json.dumps({ "printed" : [] }, indent=4))
	f = open(db_path).read()
	db = json.loads(f)

	return db

def html2plain(html):
	# remove HTML tags
	txt = re.sub(r'<.*?>', '', html)

	return txt

def preprocess(output, type=None):
	# date_str = None
	if type == 'txt':
		txt = output
	if type == 'txt' or type == 'img':
		post_date = datetime.now()
		date_str = post_date.strftime('%Y-%m-%d_%H-%M-%S')
	if type == 'rss':
		post = output
		txt = post['summary']
		year = post['published_parsed'][0]
		month = post['published_parsed'][1]
		day = post['published_parsed'][2]
		post_date = date(year, month, day)
		date_str = post_date.strftime('%Y-%m-%d')
	if type == 'txt' or type == 'rss':
		output = html2plain(txt)

		# limit printouts to 25 lines (this is a test)
		# lines = [line for line in txt.split('\n')][:25] 
		# txt = '\n'.join(lines)

	return output, date_str

def update_db(db, db_path, post, source, date, type=None):
	# add post to database
	# and check if this item is new
	item = {
		'source' : source,
		'date' : date,
		'printed' : post
	}
	if item not in db['printed']:
		already_in_db = False
		with open(db_path, 'w') as out:
			db['printed'].append(item)
			out.write(json.dumps(db, indent=4))
			out.close()
	else:
		already_in_db = True

	return already_in_db

def print_now(output, lp=None, type=None, size=None):
	# configure the printouts
	if lp:
		if type == 'rss':
			lp.set(
				invert=True,
				font='b',
				width=6, # 1-8
				height=6, # 1-8
			)
			lp.line_spacing(spacing=75) # 0 - 255
			columns = 12 # b 8 8 
		elif size == "normal":
			lp.set(
				align='left',
				font='a',
				text_type='normal', # B, U, U2, BU, BU2, NORMAL
				width=1, # 1-8
				height=1, # 1-8
				density=9, # 0-8, 9=keep unchanged
				invert=False,
				smooth=False,
				flip=False
			)
			lp.line_spacing(spacing=65) # 0 - 255
			# columns = 48 # a 1 1 
			columns = 48 # b 1 1 
		elif size == "big":
			lp.set(
				align='left',
				font='b',
				text_type='normal', # B, U, U2, BU, BU2, NORMAL
				width=8, # 1-8
				height=8, # 1-8
				invert=True
			)
			lp.line_spacing(spacing=75) # 0 - 255
			# columns = 48 # a 1 1 
			columns = 8 # b 1 1 
		elif type == 'img':
			lp.line_spacing(spacing=50) # 0 - 255

	# print
	if lp:
		if type == 'txt' or type == 'rss':
			# lp._raw(b'\x1b'+b'\x52'+b'\x32') # switch to code table, see http://docshare03.docshare.tips/files/24677/246773902.pdf for more info (does not work)
			# lp.magic.force_encoding('CP858') # does not work 
			lp.block_text(output, columns=columns) # columns=line width
			lp.cut()
		elif type == 'img':
			lp.image(output)
			lp.cut()
	else:
		sys.stderr.write('Printing output to the terminal:\n\n'+str(output)+'\n\n')