from PySide6.QtWidgets import QPushButton, QLabel, QVBoxLayout, QWidget
from PySide6.QtCore import Qt


class NavButton(QPushButton):
    """Bottom navigation button with active underline."""
    def __init__(self, text: str):
        super().__init__()
        self.setObjectName("NavBtn")
        self.setCheckable(False)
        self.setCursor(Qt.PointingHandCursor)

        self._wrap = QWidget()
        wrap_layout = QVBoxLayout(self._wrap)
        wrap_layout.setContentsMargins(0, 0, 0, 0)
        wrap_layout.setSpacing(6)

        self._label = QLabel(text)
        self._label.setAlignment(Qt.AlignCenter)

        self._underline = QWidget()
        self._underline.setObjectName("NavUnderline")
        self._underline.setFixedHeight(3)
        self._underline.setFixedWidth(36)
        self._underline.setStyleSheet("background: transparent; border-radius: 2px;")

        wrap_layout.addStretch(1)
        wrap_layout.addWidget(self._label)
        wrap_layout.addWidget(self._underline, 0, Qt.AlignHCenter)
        wrap_layout.addStretch(1)

        btn_layout = QVBoxLayout(self)
        btn_layout.setContentsMargins(0, 0, 0, 0)
        btn_layout.addWidget(self._wrap)

    def set_active(self, active: bool):
        self.setProperty("active", "true" if active else "false")
        # important to re-polish to apply dynamic property styling:
        self.style().unpolish(self)
        self.style().polish(self)