# -*- coding: utf-8 -*-

__license__   = 'GPL v3'
__copyright__ = '2012, Kovid Goyal <kovid at kovidgoyal.net>'
__docformat__ = 'restructuredtext en'

'''
Write content to PDF.
'''

import os, shutil, json

from PyQt5.Qt import (QEventLoop, QObject, QPrinter, QSizeF, Qt, QPainter,
        QPixmap, QTimer, pyqtProperty, QSize)
from PyQt5.QtWebKit import QWebSettings
from PyQt5.QtWebKitWidgets import QWebView, QWebPage

from calibre.ptempfile import PersistentTemporaryDirectory
from calibre.ebooks.pdf.pageoptions import (unit, paper_size)
from calibre.ebooks.pdf.outline_writer import Outline
from calibre.ptempfile import PersistentTemporaryFile
from calibre import (__appname__, __version__, fit_image, isosx)
from calibre.ebooks.oeb.display.webview import load_html


def get_custom_size(opts):
    custom_size = None
    if opts.custom_size is not None:
        width, sep, height = opts.custom_size.partition('x')
        if height:
            try:
                width = float(width)
                height = float(height)
                custom_size = (width, height)
            except:
                custom_size = None
    return custom_size


def get_pdf_printer(opts, for_comic=False, output_file_name=None):  # {{{
    from calibre.gui2 import must_use_qt
    must_use_qt()

    printer = QPrinter(QPrinter.HighResolution)
    custom_size = get_custom_size(opts)
    if isosx and not for_comic:
        # On OSX, the native engine can only produce a single page size
        # (usually A4). The Qt engine on the other hand produces image based
        # PDFs. If we set a custom page size using QSizeF the native engine
        # produces unreadable output, so we just ignore the custom size
        # settings.
        printer.setPaperSize(paper_size(opts.paper_size))
    else:
        if opts.output_profile.short_name == 'default' or \
                opts.output_profile.width > 9999 or opts.override_profile_size:
            if custom_size is None:
                printer.setPaperSize(paper_size(opts.paper_size))
            else:
                printer.setPaperSize(QSizeF(custom_size[0], custom_size[1]), unit(opts.unit))
        else:
            w = opts.output_profile.comic_screen_size[0] if for_comic else \
                    opts.output_profile.width
            h = opts.output_profile.comic_screen_size[1] if for_comic else \
                    opts.output_profile.height
            dpi = opts.output_profile.dpi
            printer.setPaperSize(QSizeF(float(w) / dpi, float(h) / dpi), QPrinter.Inch)

    if for_comic:
        # Comic pages typically have their own margins, or their background
        # color is not white, in which case the margin looks bad
        printer.setPageMargins(0, 0, 0, 0, QPrinter.Point)
    else:
        printer.setPageMargins(opts.margin_left, opts.margin_top,
                opts.margin_right, opts.margin_bottom, QPrinter.Point)
    printer.setOutputFormat(QPrinter.PdfFormat)
    printer.setFullPage(for_comic)
    if output_file_name:
        printer.setOutputFileName(output_file_name)
    if isosx and not for_comic:
        # Ensure we are not generating enormous image based PDFs
        printer.setOutputFormat(QPrinter.NativeFormat)

    return printer
# }}}


def draw_image_page(printer, painter, p, preserve_aspect_ratio=True):
    page_rect = printer.pageRect()
    if preserve_aspect_ratio:
        aspect_ratio = float(p.width())/p.height()
        nw, nh = page_rect.width(), page_rect.height()
        if aspect_ratio > 1:
            nh = int(page_rect.width()/aspect_ratio)
        else:  # Width is smaller than height
            nw = page_rect.height()*aspect_ratio
        __, nnw, nnh = fit_image(nw, nh, page_rect.width(),
                page_rect.height())
        dx = int((page_rect.width() - nnw)/2.)
        dy = int((page_rect.height() - nnh)/2.)
        page_rect.moveTo(dx, dy)
        page_rect.setHeight(nnh)
        page_rect.setWidth(nnw)
    painter.drawPixmap(page_rect, p, p.rect())


class Page(QWebPage):  # {{{

    def __init__(self, opts, log):
        self.log = log
        QWebPage.__init__(self)
        settings = self.settings()
        settings.setFontSize(QWebSettings.DefaultFontSize,
                opts.pdf_default_font_size)
        settings.setFontSize(QWebSettings.DefaultFixedFontSize,
                opts.pdf_mono_font_size)
        settings.setFontSize(QWebSettings.MinimumLogicalFontSize, 8)
        settings.setFontSize(QWebSettings.MinimumFontSize, 8)

        std = {'serif':opts.pdf_serif_family, 'sans':opts.pdf_sans_family,
                'mono':opts.pdf_mono_family}.get(opts.pdf_standard_font,
                        opts.pdf_serif_family)
        if std:
            settings.setFontFamily(QWebSettings.StandardFont, std)
        if opts.pdf_serif_family:
            settings.setFontFamily(QWebSettings.SerifFont, opts.pdf_serif_family)
        if opts.pdf_sans_family:
            settings.setFontFamily(QWebSettings.SansSerifFont,
                    opts.pdf_sans_family)
        if opts.pdf_mono_family:
            settings.setFontFamily(QWebSettings.FixedFont, opts.pdf_mono_family)

    def javaScriptConsoleMessage(self, msg, lineno, msgid):
        self.log.debug(u'JS:', unicode(msg))

    def javaScriptAlert(self, frame, msg):
        self.log(unicode(msg))
# }}}


class PDFWriter(QObject):  # {{{

    def __init__(self, opts, log, cover_data=None, toc=None):
        from calibre.gui2 import must_use_qt
        from calibre.utils.podofo import get_podofo
        must_use_qt()
        QObject.__init__(self)

        self.logger = self.log = log
        self.podofo = get_podofo()
        self.doc = self.podofo.PDFDoc()

        self.loop = QEventLoop()
        self.view = QWebView()
        self.page = Page(opts, self.log)
        self.view.setPage(self.page)
        self.view.setRenderHints(QPainter.Antialiasing|QPainter.TextAntialiasing|QPainter.SmoothPixmapTransform)
        self.view.loadFinished.connect(self._render_html,
                type=Qt.QueuedConnection)
        for x in (Qt.Horizontal, Qt.Vertical):
            self.view.page().mainFrame().setScrollBarPolicy(x,
                    Qt.ScrollBarAlwaysOff)
        self.render_queue = []
        self.combine_queue = []
        self.tmp_path = PersistentTemporaryDirectory(u'_pdf_output_parts')

        self.opts = opts
        self.cover_data = cover_data
        self.paged_js = None
        self.toc = toc

    def dump(self, items, out_stream, pdf_metadata):
        self.metadata = pdf_metadata
        self._delete_tmpdir()
        self.outline = Outline(self.toc, items)

        self.render_queue = items
        self.combine_queue = []
        self.out_stream = out_stream
        self.insert_cover()

        self.render_succeeded = False
        self.current_page_num = self.doc.page_count()
        self.combine_queue.append(os.path.join(self.tmp_path,
            'qprinter_out.pdf'))
        self.first_page = True
        self.setup_printer(self.combine_queue[-1])
        QTimer.singleShot(0, self._render_book)
        self.loop.exec_()
        if self.painter is not None:
            self.painter.end()
        if self.printer is not None:
            self.printer.abort()

        if not self.render_succeeded:
            raise Exception('Rendering HTML to PDF failed')

    def _render_book(self):
        try:
            if len(self.render_queue) == 0:
                self._write()
            else:
                self._render_next()
        except:
            self.logger.exception('Rendering failed')
            self.loop.exit(1)

    def _render_next(self):
        item = unicode(self.render_queue.pop(0))

        self.logger.debug('Processing %s...' % item)
        self.current_item = item
        load_html(item, self.view)

    def _render_html(self, ok):
        if ok:
            self.do_paged_render()
        else:
            # The document is so corrupt that we can't render the page.
            self.logger.error('Document cannot be rendered.')
            self.loop.exit(0)
            return
        self._render_book()

    def _pass_json_value_getter(self):
        val = json.dumps(self.bridge_value)
        return val

    def _pass_json_value_setter(self, value):
        self.bridge_value = json.loads(unicode(value))

    _pass_json_value = pyqtProperty(str, fget=_pass_json_value_getter,
            fset=_pass_json_value_setter)

    def setup_printer(self, outpath):
        self.printer = self.painter = None
        printer = get_pdf_printer(self.opts, output_file_name=outpath)
        painter = QPainter(printer)
        zoomx = printer.logicalDpiX()/self.view.logicalDpiX()
        zoomy = printer.logicalDpiY()/self.view.logicalDpiY()
        painter.scale(zoomx, zoomy)
        pr = printer.pageRect()
        self.printer, self.painter = printer, painter
        self.viewport_size = QSize(pr.width()/zoomx, pr.height()/zoomy)
        self.page.setViewportSize(self.viewport_size)

    def do_paged_render(self):
        if self.paged_js is None:
            from calibre.utils.resources import compiled_coffeescript
            self.paged_js = compiled_coffeescript('ebooks.oeb.display.utils')
            self.paged_js += compiled_coffeescript('ebooks.oeb.display.indexing')
            self.paged_js += compiled_coffeescript('ebooks.oeb.display.paged')

        self.view.page().mainFrame().addToJavaScriptWindowObject("py_bridge", self)
        evaljs = self.view.page().mainFrame().evaluateJavaScript
        evaljs(self.paged_js)
        evaljs('''
        Object.defineProperty(py_bridge, 'value', {
               get : function() { return JSON.parse(this._pass_json_value); },
               set : function(val) { this._pass_json_value = JSON.stringify(val); }
        });

        document.body.style.backgroundColor = "white";
        paged_display.set_geometry(1, 0, 0, 0);
        paged_display.layout();
        paged_display.fit_images();
        ''')
        mf = self.view.page().mainFrame()
        start_page = self.current_page_num
        if not self.first_page:
            start_page += 1
        while True:
            if not self.first_page:
                if self.printer.newPage():
                    self.current_page_num += 1
            self.first_page = False
            mf.render(self.painter)
            try:
                nsl = int(evaljs('paged_display.next_screen_location()'))
            except (TypeError, ValueError):
                break
            if nsl <= 0:
                break
            evaljs('window.scrollTo(%d, 0)'%nsl)

        self.bridge_value = tuple(self.outline.anchor_map[self.current_item])
        evaljs('py_bridge.value = book_indexing.anchor_positions(py_bridge.value)')
        amap = self.bridge_value
        if not isinstance(amap, dict):
            amap = {}  # Some javascript error occurred
        self.outline.set_pos(self.current_item, None, start_page, 0)
        for anchor, x in amap.iteritems():
            pagenum, ypos = x
            self.outline.set_pos(self.current_item, anchor, start_page + pagenum, ypos)

    def append_doc(self, outpath):
        doc = self.podofo.PDFDoc()
        with open(outpath, 'rb') as f:
            raw = f.read()
        doc.load(raw)
        self.doc.append(doc)

    def _delete_tmpdir(self):
        if os.path.exists(self.tmp_path):
            shutil.rmtree(self.tmp_path, True)
            self.tmp_path = PersistentTemporaryDirectory('_pdf_output_parts')

    def insert_cover(self):
        if not isinstance(self.cover_data, bytes):
            return
        item_path = os.path.join(self.tmp_path, 'cover.pdf')
        printer = get_pdf_printer(self.opts, output_file_name=item_path,
                for_comic=True)
        self.combine_queue.insert(0, item_path)
        p = QPixmap()
        p.loadFromData(self.cover_data)
        if not p.isNull():
            painter = QPainter(printer)
            draw_image_page(printer, painter, p,
                    preserve_aspect_ratio=self.opts.preserve_cover_aspect_ratio)
            painter.end()
            self.append_doc(item_path)
        printer.abort()

    def _write(self):
        self.painter.end()
        self.printer.abort()
        self.painter = self.printer = None
        self.append_doc(self.combine_queue[-1])

        try:
            self.doc.creator = u'%s %s [https://calibre-ebook.com]'%(
                    __appname__, __version__)
            self.doc.title = self.metadata.title
            self.doc.author = self.metadata.author
            if self.metadata.tags:
                self.doc.keywords = self.metadata.tags
            self.outline(self.doc)
            self.doc.save_to_fileobj(self.out_stream)
            self.render_succeeded = True
        finally:
            self._delete_tmpdir()
            self.loop.exit(0)

# }}}


class ImagePDFWriter(object):  # {{{

    def __init__(self, opts, log, cover_data=None, toc=None):
        self.opts = opts
        self.log = log

    def dump(self, items, out_stream, pdf_metadata):
        from calibre.utils.podofo import get_podofo
        f = PersistentTemporaryFile('_comic2pdf.pdf')
        f.close()
        self.metadata = pdf_metadata
        try:
            self.render_images(f.name, pdf_metadata, items)
            with open(f.name, 'rb') as x:
                raw = x.read()
            doc = get_podofo().PDFDoc()
            doc.load(raw)
            doc.creator = u'%s %s [https://calibre-ebook.com]'%(
                    __appname__, __version__)
            doc.title = self.metadata.title
            doc.author = self.metadata.author
            if self.metadata.tags:
                doc.keywords = self.metadata.tags
            raw = doc.write()
            out_stream.write(raw)
        finally:
            try:
                os.remove(f.name)
            except:
                pass

    def render_images(self, outpath, mi, items):
        printer = get_pdf_printer(self.opts, for_comic=True,
                output_file_name=outpath)
        printer.setDocName(mi.title)

        painter = QPainter(printer)
        painter.setRenderHints(QPainter.Antialiasing|QPainter.SmoothPixmapTransform)

        for i, imgpath in enumerate(items):
            self.log('Rendering image:', i)
            p = QPixmap()
            p.load(imgpath)
            if not p.isNull():
                if i > 0:
                    printer.newPage()
                draw_image_page(printer, painter, p)
            else:
                self.log.warn('Failed to load image', i)
        painter.end()

# }}}


