# -* coding: utf8 *-

from __future__ import division
import Invoice
import re

# our page size and margins
from .metrics import *
# our custom page style
from .custom_elements import basicPage, firstPage, address_header

# reportlab imports
from reportlab.lib.units import cm, inch
from reportlab.pdfgen import canvas as Canvas
from reportlab.lib.colors import Color


def _formatPrice(price, symbol='€'):
    '''_formatPrice(price, symbol='€'):
    Gets a floating point value and returns a formatted price, suffixed by 'symbol'. '''
    s = ("%.2f" % price).replace('.', ',')
    pat = re.compile(r'([0-9])([0-9]{3}[.,])')
    while pat.search(s):
        s = pat.sub(r'\1.\2', s)
    return s + ' ' + symbol


def _niceCount(value):
    '''_niceCount(value):
    Returns a tuple (integer , decimals) where decimals can be None'''
    if type(value) == int:
        return ('%i' % value, None)
    if round(value, 2) == int(value):
        return ('%i' % int(value), None)
    s = '%.2f' % value
    (integer, decimals) = s.split('.', 1)
    if decimals[-1] == '0':
        decimals = decimals[:-1]
    return (integer, decimals)


def _splitToWidth(canvas, text, width, font, size):
    '''_splitToWidth(canvas, text, width, font, size)
    Split a string to several lines of a given width.'''
    lines = []
    paras = text.split('\n')
    for para in paras:
        words = para.split(' ')
        while len(words) > 0:
            mywords = [words[0], ]
            del words[0]
            while len(words) > 0 and canvas.stringWidth(' '.join(mywords) + ' ' + words[0], font, size) <= width:
                mywords.append(words[0])
                del words[0]
            lines.append(' '.join(mywords))
    return lines


def _drawJustifiedString(x, y, text, canvas, width, font, size):
    text = text.strip()
    if canvas.stringWidth(text, font, size) > width:
        canvas.drawString(x, y, text)
        # too long line, I cannot handle this
        return
    if ' ' not in text:
        canvas.drawString(x, y, text)
        # no space in there, nothing to justify
        return

    words = ['%s' % w for w in text.split(' ')]
    words_width = 0.0
    for word in words:
        words_width += canvas.stringWidth(word, font, size)

    available_space = width - words_width
    available_each = available_space // float((len(words) - 1))

    my_x = x
    for idx in range(len(words)):
        word = words[idx]
        canvas.drawString(my_x, y, word)
        my_x += canvas.stringWidth(word, font, size) + available_each
    return


def address(canvas, lines):
    x = 2.0 * cm
    y = page_height - 5.0 * cm
    canvas.setFont(font, 8)
    canvas.drawString(x + 0.5 * cm, y + 0.1 * cm, 'schokokeks.org · Köchersberg 32 · 71540 Murrhardt')
    canvas.setLineWidth(1)
    canvas.line(x + 0.4 * cm, y, x + address_width, y)
    y = y - 0.2 * cm

    line_height = 11 + 0.1 * cm
    y -= line_height

    fontsize = 11
    for line in lines:
        if canvas.stringWidth(line, font, fontsize) > address_width:
            # Wenn es in zwei Zeilen passt, dann ist alles okay, ansonsten verkleinern
            if len(lines) > 4 or canvas.stringWidth(line, font, fontsize) > 2 * address_width:
                for candidate in [10.5, 10, 9.5, 9, 8.5, 8]:
                    fontsize = candidate
                    if (len(lines) <= 4 and canvas.stringWidth(line, font, fontsize) <= 2 * address_width) or canvas.stringWidth(line, font, fontsize) <= address_width:
                        break
    for line in lines:
        if canvas.stringWidth(line, font, fontsize) > address_width:
            mylines = _splitToWidth(canvas, line, address_width, font, fontsize)
            for l in mylines:
                canvas.setFont(font, fontsize)
                canvas.drawString(x + 0.5 * cm, y, l)
                y -= line_height
        else:
            canvas.setFont(font, fontsize)
            canvas.drawString(x + 0.5 * cm, y, line)
            y -= line_height


def InvoiceToPDF(iv, bankdata=True):
    from io import BytesIO
    fd = BytesIO()
    canvas = Canvas.Canvas(fd, pagesize=A4)

    if iv.tender:
        canvas.setTitle("Angebot von schokokeks.org")
    else:
        canvas.setTitle("Rechnung von schokokeks.org")

    canvas.setFont(font, 12)

    num_pages = 1
    # Waehrungssysmbol
    symbol = '€'
    y = topcontent
    font_size = default_font_size
    font_height = 0.35 * cm
    line_padding = 0.1 * cm
    line_height = font_height + 0.1 * cm

    def _partHeight(part):
        height = 0
        if type(part) == Invoice.Text:
            left, right = leftcontent, rightcontent
            if part.urgent:
                left += 1.5 * cm
                right -= 1.5 * cm
                height += len(part.paragraphs) * 3 * line_padding
                # Rechne eine Zeile mehr für den Rahmen
                height += line_height
            if part.headline:
                height += (len(_splitToWidth(canvas, part.headline, right - left, font + '-Bold', default_font_size + 1)) * line_height) + line_padding
            for para in part.paragraphs:
                height += (len(_splitToWidth(canvas, para, right - left, font, default_font_size)) * line_height) + line_padding
        elif type(part) == Invoice.Table:
            # Eine Zeile plus 2 mal line_padding für Tabellenkopf
            height = line_height + 2 * line_padding
            # Wenn nur ein Element (plus Summen) hin passt, reicht uns das
            el = part.entries[0]
            # Die Abstände oben und unten
            height += 2 * line_padding
            # Die Breite ist konservativ
            height += line_height * len(_splitToWidth(canvas, el['subject'], 9.3 * cm, font, font_size))
            if 'desc' in el and el['desc'] != '':
                height += line_height * len(_splitToWidth(canvas, el['desc'], 11 * cm, font, font_size))
            if part.vatType == 'net':
                # Eine Zeile mehr
                height += line_height + line_padding
            # Für die MwSt-Summen
            height += (line_height + line_padding) * len(part.vat)
            # Für den Rechnungsbetrag
            height += line_height + line_padding
        return height

    def _tableHead(y):
        canvas.setFont(font, font_size)
        canvas.drawString(left + (0.1 * cm), y - line_height + line_padding, 'Anz.')
        canvas.drawString(left + (2.6 * cm), y - line_height + line_padding, 'Beschreibung')
        if len(part.vat) == 1:
            canvas.drawRightString(left + (14.3 * cm), y - line_height + line_padding, 'Einzelpreis')
        else:
            canvas.drawRightString(left + (13.7 * cm), y - line_height + line_padding, 'Einzelpreis')
        canvas.drawRightString(left + (16.8 * cm), y - line_height + line_padding, 'Gesamtpreis')
        canvas.setLineWidth(0.01 * cm)
        canvas.line(left, y - line_height, right, y - line_height)
        y -= line_height + 0.02 * cm
        return y

    def _PageWrap(canvas):
        '''Seitenumbruch'''
        nonlocal num_pages
        num_pages += 1
        canvas.setFont(font, default_font_size - 2)
        canvas.drawRightString(rightcontent, bottomcontent + line_padding, 'Fortsetzung auf Seite %i' % num_pages)
        canvas.showPage()
        basicPage(canvas)
        y = topcontent - font_size
        canvas.setFillColor((0, 0, 0))
        canvas.setFont(font, font_size - 2)
        canvas.drawCentredString(leftcontent + (rightcontent - leftcontent) // 2, y, '- Seite %i -' % num_pages)

    address(canvas, iv.addresslines)

    font_size = default_font_size
    y = firstPage(canvas)
    if not bankdata:
        # Bankdaten überschreiben wenn Lastschrift
        canvas.setFillColor(Color(255, 255, 255, alpha=0.8))
        canvas.rect(leftcontent + ((rightcontent - leftcontent) // 3) * 2 - 2, bottomcontent - 2, (rightcontent - leftcontent) // 3, -40, fill=True, stroke=False)
        canvas.setFillColor(Color(0, 0, 0, alpha=1))
        canvas.saveState()
        canvas.translate(leftcontent + ((rightcontent - leftcontent) // 3) * 2 + 2, bottomcontent - 40)
        canvas.rotate(15)
        canvas.drawString(0, 0, "Bitte nicht überweisen")
        canvas.restoreState()
        # canvas.drawString(leftcontent+((rightcontent-leftcontent)/3)*2 + 2, bottomcontent - 20, "Bitte nicht überweisen")

    canvas.setFont(font + '-Bold', font_size + 3)
    min_y = y
    if iv.caption:
        canvas.drawString(leftcontent, y, iv.caption)
        min_y -= (font_size + 3) + 0.5 * cm

    if type(iv) == Invoice.Tender:
        canvas.setFont(font, font_size)
        canvas.drawString(rightcolumn, y, "Erstellungsdatum:")
        canvas.drawRightString(rightcontent, y, "%s" % iv.date.strftime('%d. %m. %Y'))
        y -= (font_size + 0.1 * cm)
    elif type(iv) == Invoice.Generic:
        canvas.setFont(font, font_size)
        canvas.drawString(rightcolumn, y, "Datum:")
        canvas.drawRightString(rightcontent, y, "%s" % iv.date.strftime('%d. %m. %Y'))
        y -= (font_size + 0.1 * cm)
    elif type(iv) == Invoice.Invoice:
        canvas.setFont(font + '-Bold', font_size)
        canvas.drawString(rightcolumn, y, "Bei Fragen bitte immer angeben:")
        y -= (font_size + 0.2 * cm)
        canvas.setFont(font, font_size)
        canvas.drawString(rightcolumn, y, "Rechnungsdatum:")
        canvas.drawRightString(rightcontent, y, "%s" % iv.date.strftime('%d. %m. %Y'))
        y -= (font_size + 0.1 * cm)
        canvas.drawString(rightcolumn, y, "Rechnungsnummer:")
        canvas.drawRightString(rightcontent, y, "%i" % iv.id)
        y -= (font_size + 0.1 * cm)
    if iv.customerno:
        canvas.drawString(rightcolumn, y, "Kundennummer:")
        canvas.drawRightString(rightcontent, y, "%s" % iv.customerno)
        y -= (font_size + 0.5 * cm)
    canvas.setFont(font, font_size)
    y = min(min_y, y)

    if iv.salutation:
        canvas.drawString(leftcontent, y, iv.salutation)
        y -= font_size + 0.2 * cm
        if type(iv) in [Invoice.Tender, Invoice.Invoice]:
            introText = 'hiermit stellen wir Ihnen die nachfolgend genannten Leistungen in Rechnung.'
            if type(iv) == Invoice.Tender:
                introText = 'hiermit unterbreiten wir Ihnen folgendes Angebot.'
            intro = _splitToWidth(canvas, introText, rightcontent - leftcontent, font, font_size)
            for line in intro:
                canvas.drawString(leftcontent, y, line)
                y -= font_size + 0.1 * cm
            y -= font_size + 0.1 * cm

    font_size = default_font_size
    for part in iv.parts:
        if y - _partHeight(part) < (bottomcontent + (0.5 * cm)):
            _PageWrap(canvas)
            y = topcontent - font_size - line_padding * 3
        # Debug: Was hat die Höhenbestimmung für diesen Teil als Höhe herausgefunden?
        # canvas.line(leftcontent, y-_partHeight(part), rightcontent, y-_partHeight(part))

        if type(part) == Invoice.Table:

            left = leftcontent
            right = rightcontent
            top = topcontent
            bottom = bottomcontent
            temp_sum = 0.0
            y = _tableHead(y)
            odd = True
            for el in part.entries:
                subject = []
                if len(part.vat) == 1:
                    subject = _splitToWidth(canvas, el['subject'], 10.3 * cm, font, font_size)
                else:
                    subject = _splitToWidth(canvas, el['subject'], 9.3 * cm, font, font_size)
                desc = []
                if 'desc' in el and el['desc'] != '':
                    desc = _splitToWidth(canvas, el['desc'], 11 * cm, font, font_size)
                need_lines = len(subject) + len(desc)

                # need page wrap?
                if y - (need_lines + 2 * font_size) < (bottomcontent + 2 * cm):
                    canvas.setFont(font, font_size)
                    # Zwischensumme
                    canvas.drawRightString(left + 14.5 * cm, y - font_height, 'Zwischensumme:')
                    canvas.drawRightString(left + 16.8 * cm, y - font_height, _formatPrice(temp_sum))
                    # page wrap
                    _PageWrap(canvas)
                    y = topcontent - font_size - line_padding * 3
                    # header
                    y = _tableHead(y)
                    odd = True
                    # übertrag
                    canvas.setFont(font, font_size)
                    canvas.drawRightString(left + 14.5 * cm, y - font_height, 'Übertrag:')
                    canvas.drawRightString(left + 16.8 * cm, y - font_height, _formatPrice(temp_sum))
                    y -= font_height + line_padding

                # Zwischensumme (inkl. aktueller Posten)
                temp_sum += el['total']
                # draw the background
                if not odd:
                    canvas.setFillColorRGB(0.9, 0.9, 0.9)
                else:
                    canvas.setFillColorRGB(1, 1, 1)
                canvas.rect(left, y - (need_lines * line_height) - (2 * line_padding), height=(need_lines * line_height) + (2 * line_padding), width=right - left, fill=1, stroke=0)
                canvas.setFillColorRGB(0, 0, 0)
                y -= line_padding
                (integer, decimals) = _niceCount(el['count'])
                canvas.drawRightString(left + 0.8 * cm, y - font_height, integer)
                suffix = ''
                if decimals:
                    suffix = ',%s' % decimals
                if el['unit']:
                    suffix = suffix + ' ' + el['unit']
                if suffix:
                    canvas.drawString(left + 0.8 * cm, y - font_height, '%s' % suffix)

                if len(part.vat) < 2:
                    canvas.drawString(left + 2.7 * cm, y - font_height, subject[0])
                    canvas.drawRightString(left + 14.3 * cm, y - font_height, _formatPrice(el['price']))
                    if el['tender']:
                        canvas.drawRightString(left + 16.8 * cm, y - font_height, 'eventual')
                    else:
                        canvas.drawRightString(left + 16.8 * cm, y - font_height, _formatPrice(el['total']))
                    subject = subject[1:]
                    x = 1
                    for line in subject:
                        canvas.drawString(left + 2.7 * cm, y - (x * line_height) - font_height, line)
                        x += 1
                    for line in desc[:-1]:
                        _drawJustifiedString(left + 2.7 * cm, y - (x * line_height) - font_height, line, canvas, 11 * cm, font, font_size)
                        x += 1
                    canvas.drawString(left + 2.7 * cm, y - (x * line_height) - font_height, desc[-1])
                    x += 1
                else:
                    canvas.drawString(left + 2.7 * cm, y - font_height, subject[0])
                    canvas.drawRightString(left + 13.3 * cm, y - font_height, _formatPrice(el['price']))
                    canvas.drawString(left + 13.7 * cm, y - font_height, str(part.vat[el['vat']][1]))
                    if el['tender']:
                        canvas.drawRightString(left + 16.8 * cm, y - font_height, 'eventual')
                    else:
                        canvas.drawRightString(left + 16.8 * cm, y - font_height, _formatPrice(el['total']))
                    subject = subject[1:]
                    x = 1
                    for line in subject:
                        canvas.drawString(left + 2.7 * cm, y - (x * line_height) - font_height, line)
                        x += 1
                    for line in desc:
                        canvas.drawString(left + 2.7 * cm, y - (x * line_height) - font_height, line)
                        x += 1
                odd = not odd
                y -= (need_lines * line_height) + line_padding
            if part.summary:
                y -= (0.3 * cm)
                if part.vatType == 'gross':
                    summaries = []
                    if len(part.vat) == 1:
                        vat = list(part.vat.keys())[0]
                        (integer, decimals) = _niceCount((vat * 100))
                        vatstr = '%s' % integer
                        if decimals:
                            vatstr += ',%s' % decimals
                        canvas.drawRightString(left + 14.5 * cm, y - font_height, 'Nettobetrag:')
                        canvas.drawRightString(left + 16.8 * cm, y - font_height, _formatPrice(part.sum - (part.sum / (vat + 1)) * vat))
                        y -= line_height
                        summaries.append(('%s%% MwSt:' % vatstr, _formatPrice((part.sum / (vat + 1)) * vat)))
                    else:
                        net = 0.0
                        for vat, vatdata in list(part.vat.items()):
                            (integer, decimals) = _niceCount((vat * 100))
                            vatstr = '%s' % integer
                            if decimals:
                                vatstr += ',%s' % decimals
                            _gross = vatdata[0]
                            _net = _gross / (1+vat)
                            _vat = _net * vat
                            summaries.append(('%s: Teilbetrag %s: Nettobetrag %s zzgl. %s%% MwSt:' % (vatdata[1], _formatPrice(_gross), _formatPrice(_net), vatstr), _formatPrice(_vat)))
                            net += _net
                        summaries.append(('Nettobetrag gesamt:', _formatPrice(net)))
                    summaries.sort()
                    for line in summaries:
                        canvas.drawRightString(left + 14.5 * cm, y - font_height, line[0])
                        canvas.drawRightString(left + 16.8 * cm, y - font_height, line[1])
                        y -= line_height
                    canvas.setFont(font + '-Bold', font_size)
                    if iv.tender:
                        canvas.drawRightString(left + 14.5 * cm, y - font_height, 'Gesamtbetrag:')
                    else:
                        canvas.drawRightString(left + 14.5 * cm, y - font_height, 'Rechnungsbetrag:')
                    canvas.drawRightString(left + 16.8 * cm, y - font_height, _formatPrice(part.sum))
                    canvas.setFont(font, font_size)
                    y -= line_height + line_padding
                else:
                    canvas.drawRightString(left + 14.5 * cm, y - font_height, 'Nettobetrag:')
                    canvas.drawRightString(left + 16.8 * cm, y - font_height, _formatPrice(part.sum))
                    y -= line_height
                    summaries = []
                    if len(part.vat) == 1:
                        vat = list(part.vat.keys())[0]
                        (integer, decimals) = _niceCount((vat * 100))
                        vatstr = '%s' % integer
                        if decimals:
                            vatstr += ',%s' % decimals
                        summaries.append(('zzgl. %s%% MwSt:' % vatstr, _formatPrice(vat * part.sum)))
                    elif len(part.vat) > 1:
                        for vat, vatdata in list(part.vat.items()):
                            (integer, decimals) = _niceCount((vat * 100))
                            vatstr = '%s' % integer
                            if decimals:
                                vatstr += ',%s' % decimals
                            summaries.append(('zzgl. %s%% MwSt (%s):' % (vatstr, vatdata[1]), _formatPrice(vat * vatdata[0])))
                    summaries.sort()
                    for line in summaries:
                        canvas.drawRightString(left + 14.5 * cm, y - font_height, line[0])
                        canvas.drawRightString(left + 16.8 * cm, y - font_height, line[1])
                        y -= line_height
                    sum = part.sum
                    for vat, vatdata in list(part.vat.items()):
                        sum += vat * vatdata[0]
                    canvas.setFont(font + '-Bold', font_size)
                    if iv.tender:
                        canvas.drawRightString(left + 14.5 * cm, y - font_height, 'Gesamtbetrag:')
                    else:
                        canvas.drawRightString(left + 14.5 * cm, y - font_height, 'Rechnungsbetrag:')
                    canvas.drawRightString(left + 16.8 * cm, y - font_height, _formatPrice(sum))
                    canvas.setFont(font, font_size)
                    y -= line_height + line_padding
        elif type(part) == Invoice.Text:
            my_font_size = font_size
            canvas.setFont(font, my_font_size)
            left, right = leftcontent, rightcontent
            firsttime = True
            headlines = []
            if part.urgent:
                left += 1.5 * cm
                right -= 1.5 * cm
            if part.headline:
                headlines = _splitToWidth(canvas, part.headline, right - left, font, my_font_size)
            for para in part.paragraphs:
                lines = _splitToWidth(canvas, para, right - left, font, my_font_size)
                if part.urgent:
                    need_height = len(lines) * line_height
                    if len(headlines) > 0:
                        need_height += len(headlines) * (line_height + 1) + line_padding
                    canvas.setFillColorRGB(0.95, 0.95, 0.95)
                    canvas.rect(left - 0.5 * cm, y - (need_height + (6 * line_padding)), height=need_height + (6 * line_padding), width=right - left + 1 * cm, fill=1, stroke=1)
                    canvas.setFillColorRGB(0, 0, 0)
                    y -= line_padding * 3
                if part.headline and firsttime:
                    firsttime = False
                    canvas.setFont(font + '-Bold', my_font_size + 1)
                    for line in headlines:
                        canvas.drawString(left, y - (font_height + 1), line)
                        y -= line_height + 1
                    y -= line_padding
                    canvas.setFont(font, my_font_size)
                for line in lines[:-1]:
                    _drawJustifiedString(left, y - font_height, line, canvas, right - left, font, my_font_size)
                    y -= line_height
                canvas.drawString(left, y - font_height, lines[-1])
                y -= line_height

                y -= line_padding * 3
            left, right = leftcontent, rightcontent
        elif type(part) == Invoice.Image:
            width = (part.imagedata.width / part.dpi) * inch
            height = width * (part.imagedata.height / part.imagedata.width)
            x = leftcontent
            if part.alignment == "center":
                x = leftcontent + (rightcontent - leftcontent)/2 - width/2
            elif part.alignment == "right":
                x = rightcontent - width
            canvas.drawInlineImage(part.imagedata, x, y-height, width=width, height=height)
            y -= line_padding + height
            if part.caption:
                canvas.drawString(x, y-font_height, part.caption)
                y -= line_height
        else:
            raise NotImplementedError("Cannot handle part of type %s" % type(part))
        y -= (0.5 * cm)

    canvas.showPage()
    canvas.save()
    pdfdata = fd.getvalue()
    return pdfdata