"""
Левая панель: поиск, выбор корневой папки, дерево подпапок,
фильтр избранного и фильтр по тегу.
"""

from PyQt6.QtWidgets import (
    QWidget, QVBoxLayout, QLabel, QLineEdit, QTreeView, QComboBox, QCheckBox
)
from PyQt6.QtGui import QFileSystemModel
from PyQt6.QtCore import QDir, pyqtSignal

from comfy_studio.core.i18n import tr
from comfy_studio.ui.widgets.translatable_text_edit import TranslatableLineEdit


class LeftPanel(QWidget):
    search_changed = pyqtSignal(str)
    root_folder_changed = pyqtSignal(str)
    filters_changed = pyqtSignal()  # избранное / тег

    def __init__(self, parent=None):
        super().__init__(parent)
        self.init_ui()

    def init_ui(self):
        layout = QVBoxLayout(self)
        layout.setContentsMargins(5, 5, 5, 5)

        self.search_input = TranslatableLineEdit()
        self.search_input.setPlaceholderText(tr("search_placeholder"))
        self.search_input.textChanged.connect(self.search_changed.emit)
        layout.addWidget(self.search_input)

        # Фильтр избранного
        self.favorites_check = QCheckBox(tr("filter_favorites"))
        self.favorites_check.stateChanged.connect(lambda _: self.filters_changed.emit())
        layout.addWidget(self.favorites_check)

        # Фильтр по тегу
        layout.addWidget(QLabel(tr("filter_tag")))
        self.tag_combo = QComboBox()
        self.tag_combo.addItem(tr("all_tags"), None)
        self.tag_combo.currentIndexChanged.connect(lambda _: self.filters_changed.emit())
        layout.addWidget(self.tag_combo)

        # Выбор активной корневой директории
        layout.addWidget(QLabel(tr("active_folder")))
        self.folder_selector = QComboBox()
        self.folder_selector.currentTextChanged.connect(self._on_folder_changed)
        layout.addWidget(self.folder_selector)

        layout.addWidget(QLabel(tr("subfolder_tree")))

        self.folder_model = QFileSystemModel()
        self.folder_model.setFilter(QDir.Filter.Dirs | QDir.Filter.NoDotAndDotDot)

        self.tree_view = QTreeView()
        self.tree_view.setModel(self.folder_model)
        self.tree_view.setHeaderHidden(True)

        for i in range(1, self.folder_model.columnCount()):
            self.tree_view.setColumnHidden(i, True)

        layout.addWidget(self.tree_view)

    # ── Публичные методы ──

    def set_tracked_folders(self, folders: list):
        self.folder_selector.blockSignals(True)
        self.folder_selector.clear()
        self.folder_selector.addItems(folders)
        self.folder_selector.blockSignals(False)

    def set_root_path(self, path: str):
        self.folder_model.setRootPath(path)
        self.tree_view.setRootIndex(self.folder_model.index(path))

    def update_tags(self, tags: list):
        """Обновляет список тегов, сохраняя текущий выбор если возможно."""
        current = self.tag_combo.currentData()
        self.tag_combo.blockSignals(True)
        self.tag_combo.clear()
        self.tag_combo.addItem(tr("all_tags"), None)
        for t in tags:
            self.tag_combo.addItem(t, t)
        if current in tags:
            self.tag_combo.setCurrentIndex(tags.index(current) + 1)
        self.tag_combo.blockSignals(False)

    def get_filters(self) -> dict:
        return {
            "favorites_only": self.favorites_check.isChecked(),
            "tag": self.tag_combo.currentData(),
        }

    def _on_folder_changed(self, path: str):
        if path:
            self.set_root_path(path)
            self.root_folder_changed.emit(path)