"""
novelWriter – Custom Widget: Progress Bars
==========================================

This file is a part of novelWriter
Copyright (C) 2023 Veronica Berglyd Olsen and novelWriter contributors

This program 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.

This program 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 this program. If not, see <https://www.gnu.org/licenses/>.
"""  # noqa

from __future__ import annotations

from math import ceil

from PyQt6.QtCore import QRect
from PyQt6.QtGui import QBrush, QColor, QPainter, QPaintEvent, QPen
from PyQt6.QtWidgets import QProgressBar, QWidget

from novelwriter.types import QtAlignCenter, QtPaintAntiAlias, QtRoundCap, QtSizeFixed, QtSolidLine, QtTransparent


class NProgressCircle(QProgressBar):
    """Extension: Circular Progress Widget.

    A custom widget that paints a circular progress indicator instead of
    a straight bar. It is also possible to set custom text for iṫ.
    """

    __slots__ = (
        "_bPen",
        "_cPen",
        "_cRect",
        "_dBrush",
        "_dPen",
        "_dRect",
        "_point",
        "_tColor",
        "_text",
    )

    def __init__(self, parent: QWidget, size: int, point: int) -> None:
        super().__init__(parent=parent)
        self._text = None
        self._point = point
        self._dRect = QRect(0, 0, size, size)
        self._cRect = QRect(point, point, size - 2 * point, size - 2 * point)
        self._dPen = QPen(QtTransparent)
        self._dBrush = QBrush(QtTransparent)
        self.setColors(
            track=self.palette().alternateBase().color(),
            bar=self.palette().highlight().color(),
            text=self.palette().text().color(),
        )
        self.setSizePolicy(QtSizeFixed, QtSizeFixed)
        self.setFixedWidth(size)
        self.setFixedHeight(size)

    def setColors(
        self,
        back: QColor | None = None,
        track: QColor | None = None,
        bar: QColor | None = None,
        text: QColor | None = None,
    ) -> None:
        """Set the colours of the widget."""
        if isinstance(back, QColor):
            self._dPen = QPen(back)
            self._dBrush = QBrush(back)
        if isinstance(bar, QColor):
            self._cPen = QPen(QBrush(bar), self._point, QtSolidLine, QtRoundCap)
        if isinstance(track, QColor):
            self._bPen = QPen(QBrush(track), self._point, QtSolidLine, QtRoundCap)
        if isinstance(text, QColor):
            self._tColor = text

    def setCentreText(self, text: str | None) -> None:
        """Replace the progress text with a custom string."""
        self._text = text
        self.setValue(self.value())  # Triggers a redraw

    def paintEvent(self, event: QPaintEvent) -> None:
        """Paint the progress bar."""
        progress = 100.0 * self.value() / self.maximum()
        angle = ceil(16 * 3.6 * progress)
        painter = QPainter(self)
        painter.setRenderHint(QtPaintAntiAlias, True)
        painter.setPen(self._dPen)
        painter.setBrush(self._dBrush)
        painter.drawEllipse(self._dRect)
        painter.setPen(self._bPen)
        painter.drawArc(self._cRect, 0, 360 * 16)
        painter.setPen(self._cPen)
        painter.drawArc(self._cRect, 90 * 16, -angle)
        painter.setPen(self._tColor)
        painter.drawText(self._cRect, QtAlignCenter, self._text or f"{progress:.1f} %")


class NProgressSimple(QProgressBar):
    """Extension: Simple Progress Widget.

    A custom widget that paints a plain bar with no other styling.
    """

    def __init__(self, parent: QWidget) -> None:
        super().__init__(parent=parent)

    def paintEvent(self, event: QPaintEvent) -> None:
        """Paint the progress bar."""
        if (value := self.value()) > 0:
            progress = ceil(self.width() * float(value) / self.maximum())
            painter = QPainter(self)
            painter.setRenderHint(QtPaintAntiAlias, True)
            painter.setPen(self.palette().highlight().color())
            painter.setBrush(self.palette().highlight())
            painter.drawRect(0, 0, progress, self.height())
