# SPDX-FileCopyrightText: Freya Bruhin (The Compiler) <mail@qutebrowser.org>
#
# SPDX-License-Identifier: GPL-3.0-or-later

"""The main browser widget for QtWebEngine."""

import mimetypes
from typing import Optional
from collections.abc import Iterable

from qutebrowser.qt import machinery
from qutebrowser.qt.core import pyqtSignal, pyqtSlot, QUrl
from qutebrowser.qt.gui import QPalette
from qutebrowser.qt.webenginewidgets import QWebEngineView
from qutebrowser.qt.webenginecore import (
    QWebEnginePage, QWebEngineCertificateError, QWebEngineSettings,
    QWebEngineHistory,
)

from qutebrowser.browser import shared
from qutebrowser.browser.webengine import webenginesettings, certificateerror
from qutebrowser.config import config
from qutebrowser.utils import log, debug, usertypes, qtutils


_QB_FILESELECTION_MODES = {
    QWebEnginePage.FileSelectionMode.FileSelectOpen: shared.FileSelectionMode.single_file,
    QWebEnginePage.FileSelectionMode.FileSelectOpenMultiple: shared.FileSelectionMode.multiple_files,
    # WORKAROUND for https://bugreports.qt.io/browse/QTBUG-91489
    #
    # QtWebEngine doesn't expose this value from its internal
    # FilePickerControllerPrivate::FileChooserMode enum (i.e. it's not included in
    # the public QWebEnginePage::FileSelectionMode enum).
    # However, QWebEnginePage::chooseFiles is still called with the matching value
    # (2) when a file input with "webkitdirectory" is used.
    QWebEnginePage.FileSelectionMode(2): shared.FileSelectionMode.folder,
}


class WebEngineView(QWebEngineView):

    """Custom QWebEngineView subclass with qutebrowser-specific features."""

    def __init__(self, *, tabdata, win_id, private, parent=None):
        super().__init__(parent)
        self._win_id = win_id
        self._tabdata = tabdata

        style = self.style()
        assert style is not None
        theme_color = style.standardPalette().color(QPalette.ColorRole.Base)
        if private:
            assert webenginesettings.private_profile is not None
            profile = webenginesettings.private_profile
            assert profile.isOffTheRecord()
        else:
            profile = webenginesettings.default_profile
        page = WebEnginePage(theme_color=theme_color, profile=profile,
                             parent=self)
        self.setPage(page)

    def render_widget(self):
        """Get the RenderWidgetHostViewQt for this view."""
        return self.focusProxy()

    def shutdown(self):
        """Shut down the underlying page."""
        page = self.page()
        assert isinstance(page, WebEnginePage), page
        page.shutdown()

    def createWindow(self, wintype):
        """Called by Qt when a page wants to create a new window.

        This function is called from the createWindow() method of the
        associated QWebEnginePage, each time the page wants to create a new
        window of the given type. This might be the result, for example, of a
        JavaScript request to open a document in a new window.

        Args:
            wintype: This enum describes the types of window that can be
                     created by the createWindow() function.

                     QWebEnginePage::WebBrowserWindow:
                         A complete web browser window.
                     QWebEnginePage::WebBrowserTab:
                         A web browser tab.
                     QWebEnginePage::WebDialog:
                         A window without decoration.
                     QWebEnginePage::WebBrowserBackgroundTab:
                         A web browser tab without hiding the current visible
                         WebEngineView.

        Return:
            The new QWebEngineView object.
        """
        debug_type = debug.qenum_key(QWebEnginePage, wintype)
        background = config.val.tabs.background

        log.webview.debug("createWindow with type {}, background {}".format(
            debug_type, background))

        if wintype == QWebEnginePage.WebWindowType.WebBrowserWindow:
            # Shift-Alt-Click
            target = usertypes.ClickTarget.window
        elif wintype == QWebEnginePage.WebWindowType.WebDialog:
            log.webview.warning("{} requested, but we don't support "
                                "that!".format(debug_type))
            target = usertypes.ClickTarget.tab
        elif wintype == QWebEnginePage.WebWindowType.WebBrowserTab:
            # Middle-click / Ctrl-Click with Shift
            # FIXME:qtwebengine this also affects target=_blank links...
            if background:
                target = usertypes.ClickTarget.tab
            else:
                target = usertypes.ClickTarget.tab_bg
        elif wintype == QWebEnginePage.WebWindowType.WebBrowserBackgroundTab:
            # Middle-click / Ctrl-Click
            if background:
                target = usertypes.ClickTarget.tab_bg
            else:
                target = usertypes.ClickTarget.tab
        else:
            raise ValueError("Invalid wintype {}".format(debug_type))

        tab = shared.get_tab(self._win_id, target)
        return tab._widget  # pylint: disable=protected-access

    def contextMenuEvent(self, ev):
        """Prevent context menus when rocker gestures are enabled."""
        if config.val.input.mouse.rocker_gestures:
            ev.ignore()
            return
        super().contextMenuEvent(ev)

    def page(self) -> "WebEnginePage":
        """Return the page for this view."""
        maybe_page = super().page()
        assert isinstance(maybe_page, WebEnginePage), maybe_page
        return maybe_page

    def settings(self) -> "QWebEngineSettings":
        """Return the settings for this view."""
        maybe_settings = super().settings()
        assert maybe_settings is not None
        return maybe_settings

    def history(self) -> "QWebEngineHistory":
        """Return the history for this view."""
        maybe_history = super().history()
        assert maybe_history is not None
        return maybe_history


def extra_suffixes_workaround(upstream_mimetypes):
    """Return any extra suffixes for mimetypes in upstream_mimetypes.

    Return any file extensions (aka suffixes) for mimetypes listed in
    upstream_mimetypes that are not already contained in there.

    WORKAROUND: for https://bugreports.qt.io/browse/QTBUG-116905
    Affected Qt versions > 6.2.2 (probably) < 6.7.0
    """
    if not (
        qtutils.version_check("6.2.3", compiled=False)
        and not qtutils.version_check("6.7.0", compiled=False)
    ):
        return set()

    suffixes = {entry for entry in upstream_mimetypes if entry.startswith(".")}
    mimes = {entry for entry in upstream_mimetypes if "/" in entry}
    python_suffixes = set()
    for mime in mimes:
        if mime.endswith("/*"):
            python_suffixes.update(
                [
                    suffix
                    for suffix, mimetype in mimetypes.types_map.items()
                    if mimetype.startswith(mime[:-1])
                ]
            )
        else:
            python_suffixes.update(mimetypes.guess_all_extensions(mime))
    return python_suffixes - suffixes


class WebEnginePage(QWebEnginePage):

    """Custom QWebEnginePage subclass with qutebrowser-specific features.

    Attributes:
        _is_shutting_down: Whether the page is currently shutting down.
        _theme_color: The theme background color.

    Signals:
        certificate_error: Emitted on certificate errors.
                           Needs to be directly connected to a slot calling
                           .accept_certificate(), .reject_certificate, or
                           .defer().
        shutting_down: Emitted when the page is shutting down.
        navigation_request: Emitted on acceptNavigationRequest.
    """

    certificate_error = pyqtSignal(certificateerror.CertificateErrorWrapper)
    shutting_down = pyqtSignal()
    navigation_request = pyqtSignal(usertypes.NavigationRequest)

    _JS_LOG_LEVEL_MAPPING = {
        QWebEnginePage.JavaScriptConsoleMessageLevel.InfoMessageLevel:
            usertypes.JsLogLevel.info,
        QWebEnginePage.JavaScriptConsoleMessageLevel.WarningMessageLevel:
            usertypes.JsLogLevel.warning,
        QWebEnginePage.JavaScriptConsoleMessageLevel.ErrorMessageLevel:
            usertypes.JsLogLevel.error,
    }

    _NAVIGATION_TYPE_MAPPING = {
        QWebEnginePage.NavigationType.NavigationTypeLinkClicked:
            usertypes.NavigationRequest.Type.link_clicked,
        QWebEnginePage.NavigationType.NavigationTypeTyped:
            usertypes.NavigationRequest.Type.typed,
        QWebEnginePage.NavigationType.NavigationTypeFormSubmitted:
            usertypes.NavigationRequest.Type.form_submitted,
        QWebEnginePage.NavigationType.NavigationTypeBackForward:
            usertypes.NavigationRequest.Type.back_forward,
        QWebEnginePage.NavigationType.NavigationTypeReload:
            usertypes.NavigationRequest.Type.reload,
        QWebEnginePage.NavigationType.NavigationTypeOther:
            usertypes.NavigationRequest.Type.other,
        QWebEnginePage.NavigationType.NavigationTypeRedirect:
            usertypes.NavigationRequest.Type.redirect,
    }

    def __init__(self, *, theme_color, profile, parent=None):
        super().__init__(profile, parent)
        self._is_shutting_down = False
        self._theme_color = theme_color
        self._set_bg_color()
        config.instance.changed.connect(self._set_bg_color)
        if machinery.IS_QT6:
            self.certificateError.connect(self._handle_certificate_error)
            # Qt 5: Overridden method instead of signal

    @config.change_filter('colors.webpage.bg')
    def _set_bg_color(self):
        col = config.val.colors.webpage.bg
        if col is None:
            col = self._theme_color
        self.setBackgroundColor(col)

    def shutdown(self):
        self._is_shutting_down = True
        self.shutting_down.emit()

    @pyqtSlot(QWebEngineCertificateError)
    def _handle_certificate_error(self, qt_error):
        """Handle certificate errors coming from Qt."""
        error = certificateerror.CertificateErrorWrapper(qt_error)
        self.certificate_error.emit(error)
        # Right now, we never defer accepting, due to a PyQt bug
        return error.certificate_was_accepted()

    if machinery.IS_QT5:
        # Overridden method instead of signal
        certificateError = _handle_certificate_error  # noqa: N815

    def javaScriptConfirm(self, url, js_msg):
        """Override javaScriptConfirm to use qutebrowser prompts."""
        if self._is_shutting_down:
            return False
        try:
            return shared.javascript_confirm(
                url, js_msg, abort_on=[self.loadStarted, self.shutting_down])
        except shared.CallSuper:
            return super().javaScriptConfirm(url, js_msg)

    def javaScriptPrompt(self, url, js_msg, default):
        """Override javaScriptPrompt to use qutebrowser prompts."""
        if self._is_shutting_down:
            return (False, "")
        try:
            return shared.javascript_prompt(
                url, js_msg, default, abort_on=[self.loadStarted, self.shutting_down])
        except shared.CallSuper:
            return super().javaScriptPrompt(url, js_msg, default)

    def javaScriptAlert(self, url, js_msg):
        """Override javaScriptAlert to use qutebrowser prompts."""
        if self._is_shutting_down:
            return
        try:
            shared.javascript_alert(
                url, js_msg, abort_on=[self.loadStarted, self.shutting_down])
        except shared.CallSuper:
            super().javaScriptAlert(url, js_msg)

    def javaScriptConsoleMessage(self, level, msg, line, source):
        """Log javascript messages to qutebrowser's log."""
        shared.javascript_log_message(self._JS_LOG_LEVEL_MAPPING[level], source, line, msg)

    def acceptNavigationRequest(self,
                                url: QUrl,
                                typ: QWebEnginePage.NavigationType,
                                is_main_frame: bool) -> bool:
        """Override acceptNavigationRequest to forward it to the tab API."""
        navigation = usertypes.NavigationRequest(
            url=url,
            navigation_type=self._NAVIGATION_TYPE_MAPPING.get(
                typ, usertypes.NavigationRequest.Type.other),
            is_main_frame=is_main_frame)
        self.navigation_request.emit(navigation)
        return navigation.accepted

    def chooseFiles(
        self,
        mode: QWebEnginePage.FileSelectionMode,
        old_files: Iterable[Optional[str]],
        accepted_mimetypes: Iterable[Optional[str]],
    ) -> list[str]:
        """Override chooseFiles to (optionally) invoke custom file uploader."""
        accepted_mimetypes_filtered = [m for m in accepted_mimetypes if m is not None]
        old_files_filtered = [f for f in old_files if f is not None]
        extra_suffixes = extra_suffixes_workaround(accepted_mimetypes_filtered)
        if extra_suffixes:
            log.webview.debug(
                "adding extra suffixes to filepicker: "
                f"before={accepted_mimetypes_filtered} "
                f"added={extra_suffixes}",
            )
            accepted_mimetypes_filtered = list(
                accepted_mimetypes_filtered
            ) + list(extra_suffixes)

        handler = config.val.fileselect.handler
        if handler == "default":
            return super().chooseFiles(
                mode, old_files_filtered, accepted_mimetypes_filtered,
            )
        assert handler == "external", handler
        try:
            qb_mode = _QB_FILESELECTION_MODES[mode]
        except KeyError:
            log.webview.warning(
                f"Got file selection mode {mode}, but we don't support that!"
            )
            return super().chooseFiles(
                mode, old_files_filtered, accepted_mimetypes_filtered,
            )

        return shared.choose_file(qb_mode=qb_mode)
