import copy
import logging
import re
import uuid
from collections import OrderedDict
from io import BytesIO

import bleach
from django.contrib.staticfiles import finders
from django.utils.formats import date_format
from django.utils.translation import ugettext_lazy as _
from PyPDF2 import PdfFileReader
from pytz import timezone
from reportlab.graphics import renderPDF
from reportlab.graphics.barcode.qr import QrCodeWidget
from reportlab.graphics.shapes import Drawing
from reportlab.lib.colors import Color
from reportlab.lib.enums import TA_CENTER, TA_LEFT, TA_RIGHT
from reportlab.lib.styles import ParagraphStyle
from reportlab.lib.units import mm
from reportlab.pdfbase import pdfmetrics
from reportlab.pdfbase.pdfmetrics import getAscentDescent
from reportlab.pdfbase.ttfonts import TTFont
from reportlab.pdfgen.canvas import Canvas
from reportlab.platypus import Paragraph

from pretix.base.models import Order, OrderPosition
from pretix.base.signals import layout_text_variables
from pretix.base.templatetags.money import money_filter
from pretix.presale.style import get_fonts

logger = logging.getLogger(__name__)


DEFAULT_VARIABLES = OrderedDict((
    ("secret", {
        "label": _("Ticket code (barcode content)"),
        "editor_sample": "tdmruoekvkpbv1o2mv8xccvqcikvr58u",
        "evaluate": lambda orderposition, order, event: orderposition.secret
    }),
    ("order", {
        "label": _("Order code"),
        "editor_sample": "A1B2C",
        "evaluate": lambda orderposition, order, event: orderposition.order.code
    }),
    ("item", {
        "label": _("Product name"),
        "editor_sample": _("Sample product"),
        "evaluate": lambda orderposition, order, event: str(orderposition.item.name)
    }),
    ("variation", {
        "label": _("Variation name"),
        "editor_sample": _("Sample variation"),
        "evaluate": lambda op, order, event: str(op.variation) if op.variation else ''
    }),
    ("item_description", {
        "label": _("Product description"),
        "editor_sample": _("Sample product description"),
        "evaluate": lambda orderposition, order, event: str(orderposition.item.description)
    }),
    ("itemvar", {
        "label": _("Product name and variation"),
        "editor_sample": _("Sample product – sample variation"),
        "evaluate": lambda orderposition, order, event: (
            '{} - {}'.format(orderposition.item.name, orderposition.variation)
            if orderposition.variation else str(orderposition.item.name)
        )
    }),
    ("item_category", {
        "label": _("Product category"),
        "editor_sample": _("Ticket category"),
        "evaluate": lambda orderposition, order, event: (
            str(orderposition.item.category.name) if orderposition.item.category else ""
        )
    }),
    ("price", {
        "label": _("Price"),
        "editor_sample": _("123.45 EUR"),
        "evaluate": lambda op, order, event: money_filter(op.price, event.currency)
    }),
    ("attendee_name", {
        "label": _("Attendee name"),
        "editor_sample": _("John Doe"),
        "evaluate": lambda op, order, ev: op.attendee_name or (op.addon_to.attendee_name if op.addon_to else '')
    }),
    ("event_name", {
        "label": _("Event name"),
        "editor_sample": _("Sample event name"),
        "evaluate": lambda op, order, ev: str(ev.name)
    }),
    ("event_date", {
        "label": _("Event date"),
        "editor_sample": _("May 31st, 2017"),
        "evaluate": lambda op, order, ev: ev.get_date_from_display(show_times=False)
    }),
    ("event_date_range", {
        "label": _("Event date range"),
        "editor_sample": _("May 31st – June 4th, 2017"),
        "evaluate": lambda op, order, ev: ev.get_date_range_display()
    }),
    ("event_begin", {
        "label": _("Event begin date and time"),
        "editor_sample": _("2017-05-31 20:00"),
        "evaluate": lambda op, order, ev: ev.get_date_from_display(show_times=True)
    }),
    ("event_begin_time", {
        "label": _("Event begin time"),
        "editor_sample": _("20:00"),
        "evaluate": lambda op, order, ev: ev.get_time_from_display()
    }),
    ("event_end", {
        "label": _("Event end date and time"),
        "editor_sample": _("2017-05-31 22:00"),
        "evaluate": lambda op, order, ev: date_format(
            ev.date_to.astimezone(timezone(ev.settings.timezone)),
            "SHORT_DATETIME_FORMAT"
        ) if ev.date_to else ""
    }),
    ("event_end_time", {
        "label": _("Event end time"),
        "editor_sample": _("22:00"),
        "evaluate": lambda op, order, ev: date_format(
            ev.date_to.astimezone(timezone(ev.settings.timezone)),
            "TIME_FORMAT"
        ) if ev.date_to else ""
    }),
    ("event_admission", {
        "label": _("Event admission date and time"),
        "editor_sample": _("2017-05-31 19:00"),
        "evaluate": lambda op, order, ev: date_format(
            ev.date_admission.astimezone(timezone(ev.settings.timezone)),
            "SHORT_DATETIME_FORMAT"
        ) if ev.date_admission else ""
    }),
    ("event_admission_time", {
        "label": _("Event admission time"),
        "editor_sample": _("19:00"),
        "evaluate": lambda op, order, ev: date_format(
            ev.date_admission.astimezone(timezone(ev.settings.timezone)),
            "TIME_FORMAT"
        ) if ev.date_admission else ""
    }),
    ("event_location", {
        "label": _("Event location"),
        "editor_sample": _("Random City"),
        "evaluate": lambda op, order, ev: str(ev.location).replace("\n", "<br/>\n")
    }),
    ("invoice_name", {
        "label": _("Invoice address: name"),
        "editor_sample": _("John Doe"),
        "evaluate": lambda op, order, ev: order.invoice_address.name if getattr(order, 'invoice_address') else ''
    }),
    ("invoice_company", {
        "label": _("Invoice address: company"),
        "editor_sample": _("Sample company"),
        "evaluate": lambda op, order, ev: order.invoice_address.company if getattr(order, 'invoice_address') else ''
    }),
    ("addons", {
        "label": _("List of Add-Ons"),
        "editor_sample": _("Addon 1\nAddon 2"),
        "evaluate": lambda op, order, ev: "<br/>".join([
            '{} - {}'.format(p.item, p.variation) if p.variation else str(p.item)
            for p in op.addons.select_related('item', 'variation')
        ])
    }),
    ("organizer", {
        "label": _("Organizer name"),
        "editor_sample": _("Event organizer company"),
        "evaluate": lambda op, order, ev: str(order.event.organizer.name)
    }),
    ("organizer_info_text", {
        "label": _("Organizer info text"),
        "editor_sample": _("Event organizer info text"),
        "evaluate": lambda op, order, ev: str(order.event.settings.organizer_info_text)
    }),
))


def get_variables(event):
    v = copy.copy(DEFAULT_VARIABLES)
    for recv, res in layout_text_variables.send(sender=event):
        v.update(res)
    return v


class Renderer:

    def __init__(self, event, layout, background_file):
        self.layout = layout
        self.background_file = background_file
        self.variables = get_variables(event)
        if self.background_file:
            self.bg_pdf = PdfFileReader(BytesIO(self.background_file.read()))
        else:
            self.bg_pdf = None

    @classmethod
    def _register_fonts(cls):
        pdfmetrics.registerFont(TTFont('Open Sans', finders.find('fonts/OpenSans-Regular.ttf')))
        pdfmetrics.registerFont(TTFont('Open Sans I', finders.find('fonts/OpenSans-Italic.ttf')))
        pdfmetrics.registerFont(TTFont('Open Sans B', finders.find('fonts/OpenSans-Bold.ttf')))
        pdfmetrics.registerFont(TTFont('Open Sans B I', finders.find('fonts/OpenSans-BoldItalic.ttf')))

        for family, styles in get_fonts().items():
            pdfmetrics.registerFont(TTFont(family, finders.find(styles['regular']['truetype'])))
            if 'italic' in styles:
                pdfmetrics.registerFont(TTFont(family + ' I', finders.find(styles['italic']['truetype'])))
            if 'bold' in styles:
                pdfmetrics.registerFont(TTFont(family + ' B', finders.find(styles['bold']['truetype'])))
            if 'bolditalic' in styles:
                pdfmetrics.registerFont(TTFont(family + ' B I', finders.find(styles['bolditalic']['truetype'])))

    def _draw_barcodearea(self, canvas: Canvas, op: OrderPosition, o: dict):
        content = o.get('content', 'secret')
        if content == 'secret':
            content = op.secret
        elif content == 'pseudonymization_id':
            content = op.pseudonymization_id

        reqs = float(o['size']) * mm
        qrw = QrCodeWidget(content, barLevel='H', barHeight=reqs, barWidth=reqs)
        d = Drawing(reqs, reqs)
        d.add(qrw)
        qr_x = float(o['left']) * mm
        qr_y = float(o['bottom']) * mm
        renderPDF.draw(d, canvas, qr_x, qr_y)

    def _get_ev(self, op, order):
        return op.subevent or order.event

    def _get_text_content(self, op: OrderPosition, order: Order, o: dict):
        ev = self._get_ev(op, order)
        if not o['content']:
            return '(error)'
        if o['content'] == 'other':
            return o['text'].replace("\n", "<br/>\n")
        elif o['content'].startswith('meta:'):
            return ev.meta_data.get(o['content'][5:]) or ''
        elif o['content'] in self.variables:
            try:
                return self.variables[o['content']]['evaluate'](op, order, ev)
            except:
                logger.exception('Failed to process variable.')
                return '(error)'
        return ''

    def _draw_textarea(self, canvas: Canvas, op: OrderPosition, order: Order, o: dict):
        font = o['fontfamily']
        if o['bold']:
            font += ' B'
        if o['italic']:
            font += ' I'

        align_map = {
            'left': TA_LEFT,
            'center': TA_CENTER,
            'right': TA_RIGHT
        }
        style = ParagraphStyle(
            name=uuid.uuid4().hex,
            fontName=font,
            fontSize=float(o['fontsize']),
            leading=float(o['fontsize']),
            autoLeading="max",
            textColor=Color(o['color'][0] / 255, o['color'][1] / 255, o['color'][2] / 255),
            alignment=align_map[o['align']]
        )
        text = re.sub(
            "<br[^>]*>", "<br/>",
            bleach.clean(
                self._get_text_content(op, order, o) or "",
                tags=["br"], attributes={}, styles=[], strip=True
            )
        )
        p = Paragraph(text, style=style)
        p.wrapOn(canvas, float(o['width']) * mm, 1000 * mm)
        # p_size = p.wrap(float(o['width']) * mm, 1000 * mm)
        ad = getAscentDescent(font, float(o['fontsize']))
        p.drawOn(canvas, float(o['left']) * mm, float(o['bottom']) * mm - ad[1])

    def draw_page(self, canvas: Canvas, order: Order, op: OrderPosition):
        for o in self.layout:
            if o['type'] == "barcodearea":
                self._draw_barcodearea(canvas, op, o)
            elif o['type'] == "textarea":
                self._draw_textarea(canvas, op, order, o)
        canvas.showPage()

    def render_background(self, buffer, title=_('Ticket')):
        from PyPDF2 import PdfFileWriter, PdfFileReader
        buffer.seek(0)
        new_pdf = PdfFileReader(buffer)
        output = PdfFileWriter()

        for page in new_pdf.pages:
            bg_page = copy.copy(self.bg_pdf.getPage(0))
            bg_page.mergePage(page)
            output.addPage(bg_page)

        output.addMetadata({
            '/Title': str(title),
            '/Creator': 'pretix',
        })
        outbuffer = BytesIO()
        output.write(outbuffer)
        outbuffer.seek(0)
        return outbuffer