"""
XslDependencyDialog - Dialog zur Anzeige des XSL-Abhängigkeitsgraphen.

Zeigt alle XSL-Dateien im konfigurierten Verzeichnis mit ihren
Import/Include-Beziehungen (vorwärts und rückwärts).
Bietet zwei Ansichten: Baumansicht und interaktiver Netzwerkgraph (vis.js).
"""

import json
import logging
import tempfile
from pathlib import Path

from PySide6.QtCore import QUrl, Qt
from PySide6.QtGui import QIcon
from PySide6.QtWidgets import QDialog, QTreeWidgetItem

from ui.XslDependencyDialog_ui import Ui_XslDependencyDialog
from xsl_dependencies import XslDependencyGraph

logger = logging.getLogger(__name__)

# Prüfe ob QWebEngineView verfügbar ist
try:
    from PySide6.QtWebEngineWidgets import QWebEngineView

    HAS_WEBENGINE = True
except ImportError:
    HAS_WEBENGINE = False
    logger.warning("PySide6-WebEngine nicht verfügbar — Netzwerkgraph-Tab deaktiviert")


class XslDependencyDialog(QDialog):
    """Dialog zur Anzeige des vollständigen XSL-Abhängigkeitsgraphen."""

    def __init__(self, parent, xsl_root_dir: Path, dependency_graph: XslDependencyGraph):
        """
        Args:
            parent: Eltern-Widget
            xsl_root_dir: Wurzelverzeichnis der XSL-Dateien
            dependency_graph: XSL-Abhängigkeitsgraph-Instanz
        """
        super().__init__(parent)
        self.xsl_root_dir = xsl_root_dir
        self.dependency_graph = dependency_graph
        self._web_view: "QWebEngineView | None" = None
        self._graph_loaded = False
        self._temp_html_file: tempfile.NamedTemporaryFile | None = None

        self.ui = Ui_XslDependencyDialog()
        self.ui.setupUi(self)

        # Netzwerkgraph-Tab ausblenden wenn WebEngine nicht verfügbar
        if not HAS_WEBENGINE:
            self.ui.tabWidget.removeTab(1)

        # Spalten konfigurieren
        self.ui.fileTree.setHeaderLabels(["XSL-Datei", "Imports", "Importiert von"])
        self.ui.fileTree.setColumnWidth(0, 300)
        self.ui.fileTree.setColumnWidth(1, 60)
        self.ui.fileTree.setColumnWidth(2, 60)

        self.ui.depTree.setHeaderLabels(["Datei", "Typ"])
        self.ui.depTree.setColumnWidth(0, 350)

        # Graph aufbauen und anzeigen
        self._full_graph = self.dependency_graph.build_full_graph(self.xsl_root_dir)
        self._reverse_map = self._build_reverse_map()
        self._populate_file_tree()

        # Signale verbinden
        self.ui.fileTree.currentItemChanged.connect(self._on_file_selected)
        self.ui.searchEdit.textChanged.connect(self._on_search_changed)
        self.ui.tabWidget.currentChanged.connect(self._on_tab_changed)

    def closeEvent(self, event):
        """Räumt temporäre Dateien und QWebEngineView auf."""
        if self._web_view is not None:
            self._web_view.setUrl(QUrl("about:blank"))
            self._web_view.deleteLater()
            self._web_view = None
        if self._temp_html_file is not None:
            try:
                Path(self._temp_html_file.name).unlink(missing_ok=True)
            except Exception:
                pass
            self._temp_html_file = None
        super().closeEvent(event)

    def _build_reverse_map(self) -> dict[Path, set[Path]]:
        """Baut eine Reverse-Map auf: Welche Dateien importieren eine gegebene Datei?"""
        reverse: dict[Path, set[Path]] = {}
        for xsl_file, deps in self._full_graph.items():
            for dep in deps:
                if dep not in reverse:
                    reverse[dep] = set()
                reverse[dep].add(xsl_file)
        return reverse

    def _rel_path(self, abs_path: Path) -> str:
        """Gibt den relativen Pfad zur XSL-Root zurück."""
        try:
            return str(abs_path.relative_to(self.xsl_root_dir))
        except ValueError:
            return abs_path.name

    def _populate_file_tree(self):
        """Befüllt den Dateibaum mit allen XSL-Dateien und Abhängigkeitszahlen."""
        self.ui.fileTree.clear()

        xsl_icon = QIcon.fromTheme("text-x-generic")

        for xsl_file in sorted(self._full_graph.keys(), key=lambda p: self._rel_path(p).lower()):
            deps_count = len(self._full_graph.get(xsl_file, set()))
            reverse_count = len(self._reverse_map.get(xsl_file, set()))

            item = QTreeWidgetItem()
            item.setText(0, self._rel_path(xsl_file))
            item.setText(1, str(deps_count) if deps_count > 0 else "")
            item.setText(2, str(reverse_count) if reverse_count > 0 else "")
            item.setData(0, Qt.ItemDataRole.UserRole, xsl_file)
            item.setIcon(0, xsl_icon)

            # Hervorhebung für Dateien mit vielen Abhängigkeiten
            if deps_count > 5 or reverse_count > 10:
                font = item.font(0)
                font.setBold(True)
                item.setFont(0, font)

            self.ui.fileTree.addTopLevelItem(item)

        total = len(self._full_graph)
        with_deps = sum(1 for deps in self._full_graph.values() if deps)
        self.ui.statusLabel.setText(f"{total} XSL-Dateien, davon {with_deps} mit Abhängigkeiten")

    def _on_file_selected(self, current: QTreeWidgetItem | None, _previous: QTreeWidgetItem | None):
        """Zeigt Abhängigkeitsdetails für die ausgewählte Datei."""
        self.ui.depTree.clear()

        if current is None:
            self.ui.rightLabel.setText("Abhängigkeiten")
            return

        xsl_file: Path = current.data(0, Qt.ItemDataRole.UserRole)
        if xsl_file is None:
            return

        rel_name = self._rel_path(xsl_file)
        self.ui.rightLabel.setText(f"Abhängigkeiten: {rel_name}")

        import_icon = QIcon.fromTheme("go-down")
        imported_by_icon = QIcon.fromTheme("go-up")

        # Sektion: "Importiert" (forward dependencies)
        deps = self._full_graph.get(xsl_file, set())
        if deps:
            imports_root = QTreeWidgetItem()
            imports_root.setText(0, f"Importiert ({len(deps)})")
            imports_root.setIcon(0, import_icon)
            font = imports_root.font(0)
            font.setBold(True)
            imports_root.setFont(0, font)

            for dep in sorted(deps, key=lambda p: self._rel_path(p).lower()):
                dep_item = QTreeWidgetItem()
                dep_item.setText(0, self._rel_path(dep))
                dep_item.setText(1, "import/include")
                dep_item.setData(0, Qt.ItemDataRole.UserRole, dep)
                imports_root.addChild(dep_item)

            self.ui.depTree.addTopLevelItem(imports_root)
            imports_root.setExpanded(True)

        # Sektion: "Wird importiert von" (reverse dependencies)
        reverse_deps = self._reverse_map.get(xsl_file, set())
        if reverse_deps:
            imported_by_root = QTreeWidgetItem()
            imported_by_root.setText(0, f"Wird importiert von ({len(reverse_deps)})")
            imported_by_root.setIcon(0, imported_by_icon)
            font = imported_by_root.font(0)
            font.setBold(True)
            imported_by_root.setFont(0, font)

            for rev in sorted(reverse_deps, key=lambda p: self._rel_path(p).lower()):
                rev_item = QTreeWidgetItem()
                rev_item.setText(0, self._rel_path(rev))
                rev_item.setText(1, "importiert diese Datei")
                rev_item.setData(0, Qt.ItemDataRole.UserRole, rev)
                imported_by_root.addChild(rev_item)

            self.ui.depTree.addTopLevelItem(imported_by_root)
            imported_by_root.setExpanded(True)

        if not deps and not reverse_deps:
            no_deps_item = QTreeWidgetItem()
            no_deps_item.setText(0, "Keine Abhängigkeiten")
            self.ui.depTree.addTopLevelItem(no_deps_item)

    def _on_search_changed(self, text: str):
        """Filtert die Dateiliste nach dem Suchbegriff."""
        search_lower = text.lower()
        for i in range(self.ui.fileTree.topLevelItemCount()):
            item = self.ui.fileTree.topLevelItem(i)
            matches = search_lower in item.text(0).lower()
            item.setHidden(not matches)

    # === Netzwerkgraph (vis.js) ===

    def _on_tab_changed(self, index: int):
        """Lazy-Init des Netzwerkgraphs beim ersten Tab-Wechsel."""
        if not HAS_WEBENGINE:
            return

        # Tab 1 = Netzwerkgraph
        if index == 1 and not self._graph_loaded:
            self._setup_network_graph()

    def _setup_network_graph(self):
        """Erstellt QWebEngineView und lädt den vis.js Netzwerkgraph."""
        self._web_view = QWebEngineView(self.ui.graphContainer)
        self.ui.graphContainerLayout.addWidget(self._web_view)

        # Graph-Daten aufbauen (nur direkte Abhängigkeiten für Kanten)
        nodes_json, edges_json = self._build_graph_data()
        html = self._generate_html(nodes_json, edges_json)

        # HTML in temporäre Datei schreiben und per URL laden
        # (setHtml() hat Größenlimit und kann bei großen Inhalten einfrieren)
        self._temp_html_file = tempfile.NamedTemporaryFile(mode="w", suffix=".html", encoding="utf-8", delete=False)
        self._temp_html_file.write(html)
        self._temp_html_file.close()
        self._web_view.setUrl(QUrl.fromLocalFile(self._temp_html_file.name))
        self._graph_loaded = True

        logger.info("Netzwerkgraph geladen")

    def _build_graph_data(self) -> tuple[str, str]:
        """
        Konvertiert den Abhängigkeitsgraph in vis.js-kompatible JSON-Strukturen.

        Returns:
            tuple[str, str]: (nodes_json, edges_json)
        """
        # Direkten Graph verwenden (nicht transitiv)
        direct_graph = self.dependency_graph.build_direct_graph(self.xsl_root_dir)

        # Pfad → ID Mapping
        all_paths = sorted(direct_graph.keys(), key=lambda p: self._rel_path(p).lower())
        path_to_id: dict[Path, int] = {path: idx for idx, path in enumerate(all_paths)}

        # Nodes
        nodes = []
        for path, node_id in path_to_id.items():
            rel = self._rel_path(path)
            label = path.name
            direct_deps = len(direct_graph.get(path, set()))
            reverse_count = len(self._reverse_map.get(path, set()))
            title = f"<b>{rel}</b><br>Importiert: {direct_deps}<br>Importiert von: {reverse_count}"
            # Knotengröße basierend auf Verbindungsanzahl
            value = direct_deps + reverse_count

            nodes.append(
                {
                    "id": node_id,
                    "label": label,
                    "title": title,
                    "value": max(value, 1),
                }
            )

        # Edges (nur direkte Abhängigkeiten)
        edges = []
        for path, deps in direct_graph.items():
            from_id = path_to_id.get(path)
            if from_id is None:
                continue
            for dep in deps:
                to_id = path_to_id.get(dep)
                if to_id is not None:
                    edges.append({"from": from_id, "to": to_id})

        return json.dumps(nodes, ensure_ascii=False), json.dumps(edges, ensure_ascii=False)

    def _generate_html(self, nodes_json: str, edges_json: str) -> str:
        """
        Generiert die HTML-Seite mit inline vis.js und Graph-Daten.

        Args:
            nodes_json: vis.js Nodes als JSON-String
            edges_json: vis.js Edges als JSON-String

        Returns:
            str: Vollständige HTML-Seite
        """
        # vis.js Bibliothek einlesen
        vis_js_path = Path(__file__).parent.parent / "res" / "vis-network.min.js"
        try:
            vis_js_content = vis_js_path.read_text(encoding="utf-8")
        except Exception as e:
            logger.error(f"Konnte vis-network.min.js nicht laden: {e}")
            return f"<html><body><h2>Fehler: vis-network.min.js nicht gefunden</h2><p>{e}</p></body></html>"

        # Hintergrundfarbe aus Qt-Palette ableiten
        palette = self.palette()
        bg_color = palette.window().color()
        text_color = palette.windowText().color()
        bg_hex = bg_color.name()
        text_hex = text_color.name()

        return f"""<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<style>
    html, body {{
        margin: 0;
        padding: 0;
        width: 100%;
        height: 100%;
        overflow: hidden;
        background-color: {bg_hex};
        color: {text_hex};
        font-family: sans-serif;
    }}
    #graph-container {{
        width: 100%;
        height: 100%;
    }}
    .vis-tooltip {{
        background-color: {bg_hex} !important;
        color: {text_hex} !important;
        border: 1px solid #888 !important;
        border-radius: 4px !important;
        padding: 8px !important;
        font-size: 13px !important;
        box-shadow: 2px 2px 6px rgba(0,0,0,0.3) !important;
    }}
</style>
<script type="text/javascript">
{vis_js_content}
</script>
</head>
<body>
<div id="graph-container"></div>
<script type="text/javascript">
    var nodesData = {nodes_json};
    var edgesData = {edges_json};

    var nodes = new vis.DataSet(nodesData);
    var edges = new vis.DataSet(edgesData);

    var container = document.getElementById('graph-container');
    var data = {{ nodes: nodes, edges: edges }};

    var options = {{
        nodes: {{
            shape: 'dot',
            scaling: {{
                min: 8,
                max: 28,
                label: {{ enabled: true, min: 10, max: 16 }}
            }},
            font: {{
                size: 12,
                color: '{text_hex}',
                strokeWidth: 2,
                strokeColor: '{bg_hex}'
            }},
            color: {{
                background: '#4a90d9',
                border: '#2c5f9e',
                highlight: {{ background: '#ff8c00', border: '#cc7000' }},
                hover: {{ background: '#5da0e9', border: '#3a6fae' }}
            }}
        }},
        edges: {{
            arrows: {{ to: {{ enabled: true, scaleFactor: 0.5 }} }},
            color: {{
                color: '#888888',
                highlight: '#ff8c00',
                hover: '#aaaaaa',
                opacity: 0.7
            }},
            smooth: {{ type: 'continuous' }}
        }},
        physics: {{
            solver: 'barnesHut',
            barnesHut: {{
                gravitationalConstant: -3000,
                centralGravity: 0.3,
                springLength: 150,
                springConstant: 0.04,
                damping: 0.09
            }},
            stabilization: {{
                enabled: true,
                iterations: 200,
                updateInterval: 25
            }}
        }},
        interaction: {{
            hover: true,
            tooltipDelay: 200,
            navigationButtons: true,
            keyboard: true
        }}
    }};

    var network = new vis.Network(container, data, options);

    // Nachbar-Hervorhebung bei Klick
    var allNodes = nodes.get();
    var originalColors = {{}};
    allNodes.forEach(function(node) {{
        originalColors[node.id] = {{
            color: node.color || options.nodes.color,
            font: node.font || options.nodes.font
        }};
    }});

    network.on("selectNode", function(params) {{
        var selectedId = params.nodes[0];
        var connectedNodes = network.getConnectedNodes(selectedId);
        var connectedSet = new Set(connectedNodes);
        connectedSet.add(selectedId);

        var updates = [];
        allNodes.forEach(function(node) {{
            if (connectedSet.has(node.id)) {{
                updates.push({{
                    id: node.id,
                    opacity: 1.0
                }});
            }} else {{
                updates.push({{
                    id: node.id,
                    opacity: 0.15
                }});
            }}
        }});
        nodes.update(updates);

        // Kanten dimmen
        var allEdges = edges.get();
        var connectedEdges = network.getConnectedEdges(selectedId);
        var connectedEdgeSet = new Set(connectedEdges);
        var edgeUpdates = [];
        allEdges.forEach(function(edge) {{
            if (connectedEdgeSet.has(edge.id)) {{
                edgeUpdates.push({{ id: edge.id, color: {{ opacity: 1.0 }} }});
            }} else {{
                edgeUpdates.push({{ id: edge.id, color: {{ opacity: 0.08 }} }});
            }}
        }});
        edges.update(edgeUpdates);
    }});

    network.on("deselectNode", function() {{
        // Alle Knoten zurücksetzen
        var updates = [];
        allNodes.forEach(function(node) {{
            updates.push({{
                id: node.id,
                opacity: 1.0
            }});
        }});
        nodes.update(updates);

        // Alle Kanten zurücksetzen
        var allEdges = edges.get();
        var edgeUpdates = [];
        allEdges.forEach(function(edge) {{
            edgeUpdates.push({{ id: edge.id, color: {{ opacity: 0.7 }} }});
        }});
        edges.update(edgeUpdates);
    }});
</script>
</body>
</html>"""