"""Chọn project và đổi chế độ xem cho GraphRAG — R08-T14.

Đồ thị luôn thuộc về một project. Đổi project là phải quét lại từ đầu, nên
phần này giữ luôn việc dọn kết quả cũ trước khi nạp cái mới.

Cùng kiểu mixin, xem ghi chú ở đầu ``presentation/shell/nav_rail.py``.
"""
from __future__ import annotations

from .graph_qa_widget import GraphQaMixin
from .graph_render import GraphRenderMixin
from .graph_scene import _Edge, _GraphView, _Node
import re
import sys
from pathlib import Path
from PySide6.QtCore import QPointF, Qt, QTimer, Signal
from PySide6.QtGui import QColor
from PySide6.QtWidgets import QComboBox, QFileDialog, QGraphicsScene, QGraphicsView, QHBoxLayout, QLabel, QLineEdit, QPushButton, QSplitter, QStackedWidget, QTabBar, QTextBrowser, QVBoxLayout, QWidget
from ...theme import current_palette
from ...core.worker import AgentWorker
from ...i18n import on_language_changed, tr
from ...state import AppContext
from ...ui.icons import collapse_right_icon, icon
from ...ui.widgets import CollapseStrip


class GraphProjectMixin:
    """Chọn project + đổi tab xem. Trộn vào StructureGraphView."""

    def _retranslate(self) -> None:
        self.path_edit.setPlaceholderText(tr("structure.path_placeholder"))
        self._pick_btn.setText(tr("structure.browse"))
        self._scan_btn.setText(tr("structure.scan"))
        self._export_btn.setText(tr("structure.export_png"))
        # Both views are named at once now, so neither label depends on state.
        self.view_tabs.setTabText(0, tr("structure.graph_btn"))
        self.view_tabs.setTabText(1, tr("structure.msgs_btn"))
        self.view_tabs.setTabToolTip(1, tr("structure.msgs_tooltip"))
        self._ag_collapse.setToolTip(tr("structure.collapse_agent_tooltip"))
        self._ag_label.setText(tr("structure.agent_header"))
        self.ask_edit.setPlaceholderText(tr("structure.ask_placeholder"))
        self._ask_btn.setText(tr("structure.ask"))
        if self._detail_mode == "idle":
            self.detail.setPlaceholderText(tr("structure.detail_placeholder"))
        self._agent_strip.setToolTip(tr("structure.expand_agent_tooltip"))
        self.project_combo.setToolTip(tr("structure.project_tooltip"))
        self._refresh_project_combo()
    def _refresh_project_combo(self) -> None:
        from ...core.projects import list_projects

        keep = self._active_project_id
        self.project_combo.blockSignals(True)
        self.project_combo.clear()
        self.project_combo.addItem(tr("structure.project_none"), "")
        row_to_select = 0
        for i, p in enumerate(list_projects(), start=1):
            self.project_combo.addItem(p.name, p.project_id)
            if p.project_id == keep:
                row_to_select = i
        self.project_combo.setCurrentIndex(row_to_select)
        self.project_combo.blockSignals(False)
    def set_project(self, project_id: str) -> None:
        pid = project_id or ""
        self._refresh_project_combo()
        target = self.project_combo.findData(pid)
        if target < 0:
            target = 0
        if self.project_combo.currentIndex() == target:
            self._on_project_changed(target)
        else:
            self.project_combo.setCurrentIndex(target)
    def _on_project_changed(self, _idx: int) -> None:
        from ...core.projects import load_project

        pid = self.project_combo.currentData() or ""
        project_changed = pid != self._active_project_id
        if project_changed:
            self._clear_extracts()      # different workspace → drop temp extraction
        self._active_project_id = pid
        locked = bool(pid)
        self.path_edit.setReadOnly(locked)
        # Also disable the folder-pick button — otherwise the scan path is only
        # "locked" against typing, but the picker could still repoint it outside
        # the selected project's sandbox, breaking GraphRAG scope isolation.
        self._pick_btn.setEnabled(not locked)
        if locked:
            project = load_project(pid)
            if project is not None:
                self.path_edit.setText(str(project.workspace_dir()))
        if project_changed:
            # Mark it and scan on the next visit rather than now. The rail's
            # project picker made switching a one-click thing from any screen,
            # and each switch rebuilt this graph — a folder walk plus a force
            # layout plus a full setHtml of the D3 page — for a tab that was
            # usually not even on screen. auto_scan_and_fit() picks the flag up
            # when GraphRAG is actually opened.
            self._needs_scan = True
    def _pick(self) -> None:
        chosen = QFileDialog.getExistingDirectory(self, tr("structure.pick_folder_title"), self.path_edit.text())
        if chosen:
            self.path_edit.setText(chosen)
    def _on_view_tab(self, index: int) -> None:
        """Tab 0 = graph, tab 1 = messages. Same two views as before, now named
        on screen instead of hidden behind one button's changing label."""
        if index == 1:
            self._reload_messages()
            self._stack.setCurrentWidget(self._msgs_view)
        else:
            self._stack.setCurrentWidget(self.web if self.web is not None else self.view)