"""Monochrome play/pause icons for the dashboard toolbar (avoids Windows emoji glyphs)."""

from __future__ import annotations

from typing import Literal

from PyQt5.QtCore import QPointF, QRectF, Qt
from PyQt5.QtGui import QColor, QIcon, QPainter, QPixmap, QPolygonF

TransportKind = Literal["play", "pause"]

_DEFAULT_ICON_PX = 18


def transport_icon(kind: TransportKind, color: str, *, size: int = _DEFAULT_ICON_PX) -> QIcon:
    """Build a flat play triangle or pause bars in ``color`` (#rrggbb)."""
    pixmap = QPixmap(size, size)
    pixmap.fill(Qt.transparent)

    painter = QPainter(pixmap)
    painter.setRenderHint(QPainter.Antialiasing, True)
    painter.setBrush(QColor(color))
    painter.setPen(Qt.NoPen)

    if kind == "play":
        w = size * 0.52
        h = size * 0.60
        x0 = (size - w) * 0.58
        y0 = (size - h) / 2.0
        painter.drawPolygon(
            QPolygonF(
                [
                    QPointF(x0, y0),
                    QPointF(x0, y0 + h),
                    QPointF(x0 + w, y0 + h / 2.0),
                ]
            )
        )
    else:
        bar_w = size * 0.17
        bar_h = size * 0.60
        gap = size * 0.14
        y0 = (size - bar_h) / 2.0
        x0 = (size - (2.0 * bar_w + gap)) / 2.0
        radius = max(1.0, size * 0.06)
        painter.drawRoundedRect(QRectF(x0, y0, bar_w, bar_h), radius, radius)
        painter.drawRoundedRect(QRectF(x0 + bar_w + gap, y0, bar_w, bar_h), radius, radius)

    painter.end()
    return QIcon(pixmap)