from flask import Flask, Response, redirect, url_for, request, session, abort, render_template, send_file
from flask_login import LoginManager, UserMixin, login_required, login_user, logout_user, current_user
from PIL import Image, ImageFont, ImageDraw
import qrcode
from io import BytesIO
import json, random, re, string

app = Flask(__name__)
systemURL = 'http://192.168.0.11:5000/' #FULL URL with a '/' at the end
systemURL = 'http://10.0.1.115:5000/'
randomchars = 'ABCDEFGHIJKLMNOPQRSTUVWXYZ123456789' #note the lack of zero

with open('links.json', 'r') as infile:
	links = json.load(infile)

def saveFile():
	with open('links.json', 'w') as outfile:
		json.dump(links, outfile)

def randomToken():
	code = ""
	for i in range(0,6):
		code += random.choice(randomchars)
	return code

def codeValidation(code):
	if len(code) not in range (3,10):
		return False
	if re.match('^[\w-]+$', code) is None:
		return False
	return True

def codeLink(code):
	global links
	if code not in links:
		return False
	if len(links[code]['url'])==0:
		return None
	return links[code]['url']

def createNewCode():
	code=randomToken()
	while code in links: #danger!
		code=randomToken()
	links[code]={'url':''}
	return code

def serveImage(img):
    img_io = BytesIO()
    img.save(img_io, 'PNG')
    img_io.seek(0)
    return send_file(img_io, mimetype='image/png')

@app.route('/code/<code>')
def serveCode(code):
	code = code[:code.find('.')]
	if codeValidation(code) is False:
		return send_file('static/invalid.png', mimetype='image/png')
	qr = qrcode.QRCode(
    	version=1,
    	error_correction=qrcode.constants.ERROR_CORRECT_M,
    	box_size=8,
    	border=3,
	)
	qr.add_data('systemURL + code')
	qr.make(fit=True)
	img = qr.make_image(fill_color="black", back_color="white")
	return serveImage(img)

@app.route("/edit", methods=['GET', 'POST'])
def edit():
	code = request.form.get("code")
	print ("code: {}".format(code))
	if codeLink(code) is False:
		return render_template('invalid.html', code=code)
	if codeLink(code) is not None:
		return render_template('cantedit.html', url=codeLink(code))
	url = request.form.get("url")
	if url is None:
		return render_template('editlink.html', code=code)
	#Saving the link:
	if url.lower().startswith('https://') is False and url.lower().startswith('http://') is False:
		return render_template('message.html', message="Only http:// and https:// links alowed. Plz fix your link!")
	if len(url)>1000:
		return render_template('message.html', message="This link is too long! It probably contains tracking data or other crap. Please find a shorter link.")
	links[code]['url']=url
	saveFile()
	return render_template('success.html')

@app.route("/admin")
def admin():
	return render_template('admin.html')

@app.route("/generate", methods=['GET', 'POST'])
def generate():
	howmany = request.form.get("howmany")
	if howmany is None:
		return render_template('generate.html')
	codes = []
	for i in range(0, int(howmany)):
		codes.append(createNewCode())
	columns = 4
	codesarray = [codes[i:i+columns] for i in range(0, len(codes), columns)]
	saveFile()
	humanSystemURL = systemURL[systemURL.find('//')+2:]
	return render_template("printlabels.html", codes=codesarray, systemURL=humanSystemURL, codegenURL=systemURL+'code/', format='.png')

@app.route("/list")
def list():
	linklist = []
	for key, value in links.items():
		if len(value['url'])>0:
			linklist.append({'code':key, 'url':value['url']})
	return render_template('list.html', linklist=linklist)

@app.route('/', defaults={'path': ''})
@app.route('/<path:path>')
def catch_all(path):
	if len(path)==0:
		return render_template('welcome.html')
	if path in links:
		if codeLink(path) is not None:
			return redirect(links[path]['url'], code=302)
		else:
			return render_template('newcode.html', code=path)
	else:
		return render_template('invalid.html', code=path)