from PySide6.QtWidgets import (QWidget, QPushButton, QVBoxLayout,
                               QSizePolicy)
from PySide6.QtCore import Signal, Qt, QObject
from PySide6.QtGui import QFont

class FrequencyButtonGroup(QWidget):
    """振捣频率选择按钮组"""
    # 该信号frequency_changed，用于振捣频率的控制逻辑，表示需要按照int类型的频率开始振捣
    frequency_changed = Signal(int)  # 选中切换信号（新选中频率）
    
    # 该信号frequency_cleared，用于停止振捣
    frequency_cleared = Signal()     # 取消选中信号（无参数）

    def __init__(self, parent=None):
        super().__init__(parent)
        self.setFixedSize(115, 159)
        self._init_ui()
        self._selected_freq = None  # 当前选中的频率（None表示未选中）
        

    def _init_ui(self):
        """初始化UI:垂直排列3个按钮, 设置样式和交互"""
        # 1. 布局：垂直排列，间隔16px
        self.layout = QVBoxLayout(self)
        self.layout.setSpacing(16)  # 按钮间间隔16px
        self.layout.setContentsMargins(0, 0, 0, 0)  # 去除外层边距
        self.layout.setAlignment(Qt.AlignCenter)  # 按钮垂直居中

        # 2. 按钮配置：频率列表、样式
        self.freq_buttons = {}  # 存储按钮映射：{频率值: 按钮实例}
        freq_list = [220, 230, 240]  # 频率设置，设置三个频率
        font = QFont()
        font.setPointSize(15)  # 字体大小15px

        for freq in freq_list:
            btn = QPushButton(f"{freq}Hz", self)
            btn.setFont(font)
            btn.setSizePolicy(QSizePolicy.Fixed, QSizePolicy.Fixed)  # 固定尺寸
            btn.setFixedSize(96, 36)  # 按钮固定大小（匹配背景图尺寸）
            btn.setCursor(Qt.PointingHandCursor)

            # 3. 绑定点击事件
            btn.clicked.connect(lambda checked, target_freq=freq: self._on_btn_clicked(target_freq))

            # 4. 设置默认样式（未选中状态）
            self._set_btn_style(btn, is_selected=False)

            # 5. 添加到布局和映射表
            self.layout.addWidget(btn)
            self.freq_buttons[freq] = btn

        # 6. 禁止布局拉伸（按钮垂直居中，不填充多余空间）
        self.layout.addStretch()

    def _set_btn_style(self, btn, is_selected: bool):
        """设置按钮样式"""
        if is_selected:
            btn.setStyleSheet("""
                QPushButton {
                    background-image: url(images/频率按钮2.png);
                    background-repeat: no-repeat;
                    background-position: center;
                    background-origin: content-box;
                    background-clip: content-box;
                    color: #05267d;
                    border: none;
                    padding: 0px;
                }
                QPushButton:hover {
                    opacity: 0.95;
                    background-image: url(images/频率按钮2.png);
                    background-repeat: no-repeat;
                    background-position: center;
                    background-origin: content-box;
                    background-clip: content-box;
                }
            """)
        else:
            btn.setStyleSheet("""
                QPushButton {
                    background-image: url(images/频率按钮1.png);
                    background-repeat: no-repeat;
                    background-position: center;
                    background-origin: content-box;
                    background-clip: content-box;
                    color: #3bfff8;
                    border: none;
                    padding: 0px;
                }
                QPushButton:hover {
                    opacity: 0.95;
                    background-image: url(images/频率按钮1.png);
                    background-repeat: no-repeat;
                    background-position: center;
                    background-origin: content-box;
                    background-clip: content-box;
                }
            """)
        btn.repaint()

    def _on_btn_clicked(self, target_freq):
        """按钮点击事件：支持切换选中/取消选中"""
        if target_freq == self._selected_freq:
            self.clear_selection()
            self.frequency_cleared.emit()
            return

        if self._selected_freq is not None:
            prev_btn = self.freq_buttons[self._selected_freq]
            self._set_btn_style(prev_btn, is_selected=False)

        current_btn = self.freq_buttons[target_freq]
        self._set_btn_style(current_btn, is_selected=True)
        self._selected_freq = target_freq
        self.frequency_changed.emit(target_freq)

    def _set_frequency_show(self, target_freq:int):
        """设置振捣频率, 只修改显示, 不控制变频器"""
        if self._selected_freq is not None:
            prev_btn = self.freq_buttons[self._selected_freq]
            self._set_btn_style(prev_btn, is_selected=False)

        current_btn = self.freq_buttons[target_freq]
        self._set_btn_style(current_btn, is_selected=True)
        self._selected_freq = target_freq

    # ------------------- 外部接口 -------------------
    def set_selected_frequency(self, freq: int):
        """ 设置显示选中的频率, 只显示不控制 """
        try:
            freq_int = int(freq)
            if freq_int not in self.freq_buttons:
                # 除了220、230、240，其他的数值(比如:0)都表示取消显示的频率 
                self.clear_selection()
                return
            self._set_frequency_show(freq_int)
        except (ValueError, TypeError):
            pass  # 传入的振捣频率类型错误，维持原频率
        

    def get_selected_frequency(self):
        """获取当前选中的频率（外部接口）,没有选中返回None"""
        return self._selected_freq

    def clear_selection(self):
        """清除所有选中状态（内部调用+外部接口）"""
        if self._selected_freq is not None:
            prev_btn = self.freq_buttons[self._selected_freq]
            self._set_btn_style(prev_btn, is_selected=False)
            self._selected_freq = None