# vim: ft=python fileencoding=utf-8 sts=4 sw=4 et:

# Copyright 2016-2018 Florian Bruhin (The Compiler) <mail@qutebrowser.org>
#
# This file is part of qutebrowser.
#
# qutebrowser is free software: you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.
#
# qutebrowser is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with qutebrowser.  If not, see <http://www.gnu.org/licenses/>.

"""Showing messages above the statusbar."""


from PyQt5.QtCore import pyqtSlot, pyqtSignal, QTimer, Qt, QSize
from PyQt5.QtWidgets import QWidget, QVBoxLayout, QLabel, QSizePolicy

from qutebrowser.config import config
from qutebrowser.utils import usertypes


class Message(QLabel):

    """A single error/warning/info message."""

    def __init__(self, level, text, replace, parent=None):
        super().__init__(text, parent)
        self.replace = replace
        self.setAttribute(Qt.WA_StyledBackground, True)
        stylesheet = """
            padding-top: 2px;
            padding-bottom: 2px;
        """
        if level == usertypes.MessageLevel.error:
            stylesheet += """
                background-color: {{ conf.colors.messages.error.bg }};
                color: {{ conf.colors.messages.error.fg }};
                font: {{ conf.fonts.messages.error }};
                border-bottom: 1px solid {{ conf.colors.messages.error.border }};
            """
        elif level == usertypes.MessageLevel.warning:
            stylesheet += """
                background-color: {{ conf.colors.messages.warning.bg }};
                color: {{ conf.colors.messages.warning.fg }};
                font: {{ conf.fonts.messages.warning }};
                border-bottom:
                    1px solid {{ conf.colors.messages.warning.border }};
            """
        elif level == usertypes.MessageLevel.info:
            stylesheet += """
                background-color: {{ conf.colors.messages.info.bg }};
                color: {{ conf.colors.messages.info.fg }};
                font: {{ conf.fonts.messages.info }};
                border-bottom: 1px solid {{ conf.colors.messages.info.border }}
            """
        else:  # pragma: no cover
            raise ValueError("Invalid level {!r}".format(level))
        # We don't bother with set_register_stylesheet here as it's short-lived
        # anyways.
        config.set_register_stylesheet(self, stylesheet=stylesheet,
                                       update=False)


class MessageView(QWidget):

    """Widget which stacks error/warning/info messages."""

    update_geometry = pyqtSignal()

    def __init__(self, parent=None):
        super().__init__(parent)
        self._messages = []
        self._vbox = QVBoxLayout(self)
        self._vbox.setContentsMargins(0, 0, 0, 0)
        self._vbox.setSpacing(0)
        self.setSizePolicy(QSizePolicy.Expanding, QSizePolicy.Fixed)

        self._clear_timer = QTimer()
        self._clear_timer.timeout.connect(self.clear_messages)
        config.instance.changed.connect(self._set_clear_timer_interval)

        self._last_text = None

    def sizeHint(self):
        """Get the proposed height for the view."""
        height = sum(label.sizeHint().height() for label in self._messages)
        # The width isn't really relevant as we're expanding anyways.
        return QSize(-1, height)

    @config.change_filter('messages.timeout')
    def _set_clear_timer_interval(self):
        """Configure self._clear_timer according to the config."""
        interval = config.val.messages.timeout
        if interval > 0:
            interval *= min(5, len(self._messages))
            self._clear_timer.setInterval(interval)

    @pyqtSlot()
    def clear_messages(self):
        """Hide and delete all messages."""
        for widget in self._messages:
            self._vbox.removeWidget(widget)
            widget.hide()
            widget.deleteLater()
        self._messages = []
        self._last_text = None
        self.hide()
        self._clear_timer.stop()

    @pyqtSlot(usertypes.MessageLevel, str, bool)
    def show_message(self, level, text, replace=False):
        """Show the given message with the given MessageLevel."""
        if text == self._last_text:
            return

        if replace and self._messages and self._messages[-1].replace:
            old = self._messages.pop()
            old.hide()

        widget = Message(level, text, replace=replace, parent=self)
        self._vbox.addWidget(widget)
        widget.show()
        self._messages.append(widget)
        self._last_text = text
        self.show()
        self.update_geometry.emit()
        if config.val.messages.timeout != 0:
            self._set_clear_timer_interval()
            self._clear_timer.start()

    def mousePressEvent(self, e):
        """Clear messages when they are clicked on."""
        if e.button() in [Qt.LeftButton, Qt.MiddleButton, Qt.RightButton]:
            self.clear_messages()
