/* HermesCustom — Lukas' additions to obsidian-web-viewer
 *
 * Loaded by vault.html (one-line patch) AFTER the main script. Initializes
 * automatically via HermesCustom.init() at the bottom of this file.
 *
 * Features:
 *   1. Current-page highlighting in 3D Graph
 *   2. Click-to-navigate on 3D Graph nodes (Three.js raycasting)
 *   3. Responsive layout (graph collapses below 1024px, tree below 768px)
 *
 * Design notes: see docs/ARCHITECTURE.md
 */
(function() {
    'use strict';

    window.HermesCustom = window.HermesCustom || {};

    const HermesCustom = window.HermesCustom;

    // ============================================================
    // 1. Current-page highlighting
    // ============================================================

    /**
     * Determine which file is currently being viewed.
     * Uses URL ?file=<path> parameter, or falls back to extracting from the
     * page content (the last file fetched via loadFile).
     */
    HermesCustom.getCurrentFile = function() {
        // Method 1: ?file= query param (preferred)
        const params = new URLSearchParams(window.location.search);
        const fileParam = params.get('file');
        if (fileParam) return fileParam;

        // Method 2: Parse from URL hash if obv uses hash-based routing
        if (window.location.hash) {
            const hashMatch = window.location.hash.match(/file=([^&]+)/);
            if (hashMatch) return decodeURIComponent(hashMatch[1]);
        }

        // Method 3: Track via the last loadFile() call (set up in init)
        return HermesCustom._lastLoadedFile || null;
    };

    /**
     * Find all WikiLink targets in the currently loaded file's content.
     * We hook into the renderMarkdown flow by tracking what was last loaded.
     */
    HermesCustom.getConnectedFiles = function(currentFile) {
        if (!currentFile) return [];
        // Use the global graph data loaded by obv's fetch('/api/vault/graph')
        const graphData = HermesCustom._graphData;
        if (!graphData) return [];

        const connections = graphData.edges
            .filter(e => e.source === currentFile)
            .map(e => e.target);

        // Also outgoing from current file (WikiLinks from current page)
        // And bidirectional awareness
        return connections;
    };

    /**
     * Highlight the current node + connected nodes in the 3D Graph.
     * Uses obv's global graph variables (graphScene, graphNodeObjects).
     */
    HermesCustom.highlightCurrentNode = function() {
        const currentFile = HermesCustom.getCurrentFile();
        if (!currentFile) return;

        // Hook into obv's globals (set after graph render)
        if (typeof window.graphScene === 'undefined' || !window.graphNodeObjects) {
            // Graph not yet built — try again shortly
            setTimeout(HermesCustom.highlightCurrentNode, 500);
            return;
        }

        const connected = new Set(HermesCustom.getConnectedFiles(currentFile));
        connected.add(currentFile);

        // Iterate node meshes and adjust material
        window.graphNodeObjects.forEach((mesh, nodeId) => {
            const isCurrent = (nodeId === currentFile);
            const isConnected = connected.has(nodeId) && !isCurrent;

            if (isCurrent) {
                // Bright + slightly larger + emissive glow
                mesh.material.color.setHex(0xFFD700); // gold
                mesh.material.emissive.setHex(0xFFD700);
                mesh.material.emissiveIntensity = 0.6;
                mesh.scale.set(1.5, 1.5, 1.5);
            } else if (isConnected) {
                // Brighter than default, smaller than current
                mesh.material.color.setHex(0x89b4fa); // light blue
                mesh.material.emissive.setHex(0x89b4fa);
                mesh.material.emissiveIntensity = 0.3;
                mesh.scale.set(1.1, 1.1, 1.1);
            } else {
                // Dim everything else
                mesh.material.color.setHex(0x313244); // muted
                mesh.material.emissiveIntensity = 0;
                mesh.material.opacity = 0.2;
                mesh.material.transparent = true;
            }
        });
    };

    // ============================================================
    // 2. Click-to-navigate on 3D Graph
    // ============================================================

    HermesCustom.setupGraphClickHandler = function() {
        if (!window.graphRenderer || !window.graphScene || !window.graphCamera) {
            setTimeout(HermesCustom.setupGraphClickHandler, 500);
            return;
        }

        const raycaster = new THREE.Raycaster();
        const mouse = new THREE.Vector2();

        window.graphRenderer.domElement.addEventListener('click', (event) => {
            const rect = window.graphRenderer.domElement.getBoundingClientRect();
            mouse.x = ((event.clientX - rect.left) / rect.width) * 2 - 1;
            mouse.y = -((event.clientY - rect.top) / rect.height) * 2 + 1;

            raycaster.setFromCamera(mouse, window.graphCamera);
            const intersects = raycaster.intersectObjects(
                Object.values(window.graphNodeObjects || {})
            );

            if (intersects.length > 0) {
                const nodeId = intersects[0].object.userData.nodeId;
                if (nodeId && typeof window.loadFile === 'function') {
                    window.loadFile(nodeId);
                    window.history.pushState({}, '', `?file=${encodeURIComponent(nodeId)}`);
                }
            }
        });
    };

    // ============================================================
    // 3. Responsive layout
    // ============================================================

    HermesCustom.responsiveLayout = function() {
        const applyLayout = () => {
            const app = document.querySelector('.vault-app');
            if (!app) return;

            const width = window.innerWidth;
            if (width < 768) {
                // Mobile: tree collapses to hamburger, graph hidden by default
                app.classList.add('mobile-mode');
                app.classList.remove('graph-visible');
            } else if (width < 1024) {
                // Tablet: tree visible, graph collapses to bottom panel
                app.classList.add('tablet-mode');
                app.classList.remove('mobile-mode');
            } else {
                // Desktop: full 3-panel layout
                app.classList.remove('mobile-mode', 'tablet-mode');
            }
        };

        // Throttled resize handler
        let resizeTimer;
        window.addEventListener('resize', () => {
            clearTimeout(resizeTimer);
            resizeTimer = setTimeout(applyLayout, 150);
        });

        applyLayout(); // Initial
    };

    /**
     * Inject responsive CSS into <head> (since vault.html doesn't have these)
     * Must run early so it doesn't conflict with obv's layout.
     */
    HermesCustom.injectResponsiveCSS = function() {
        if (document.getElementById('hermes-custom-css')) return;

        const style = document.createElement('style');
        style.id = 'hermes-custom-css';
        style.textContent = `
/* === Tablet (768px - 1023px): graph → bottom panel === */
@media (max-width: 1023px) {
    .vault-app.tablet-mode {
        grid-template-columns: 240px 1fr !important;
        grid-template-rows: 48px 1fr 200px !important;
    }
    .vault-app.tablet-mode .vault-graph {
        grid-column: 1 / -1 !important;
        grid-row: 3 !important;
        border-left: none !important;
        border-top: 1px solid var(--border);
    }
    .vault-app.tablet-mode .vault-content {
        grid-column: 2 !important;
    }
}

/* === Mobile (<768px): tree → hamburger menu === */
@media (max-width: 767px) {
    .vault-app.mobile-mode {
        grid-template-columns: 1fr !important;
        grid-template-rows: 48px 1fr !important;
    }
    .vault-app.mobile-mode .vault-sidebar {
        position: fixed;
        top: 48px;
        left: 0;
        bottom: 0;
        width: 280px;
        transform: translateX(-100%);
        transition: transform 0.2s ease;
        z-index: 100;
    }
    .vault-app.mobile-mode .vault-sidebar.open {
        transform: translateX(0);
    }
    .vault-app.mobile-mode .vault-graph {
        display: none;
    }
}

/* === Hamburger toggle button (mobile only) === */
.hermes-mobile-toggle {
    display: none;
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    color: var(--text-secondary);
    padding: 4px 10px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 12px;
}
@media (max-width: 767px) {
    .hermes-mobile-toggle { display: inline-block; }
}
        `;
        document.head.appendChild(style);

        // Add hamburger button to header
        const header = document.querySelector('.vault-header');
        if (header && !document.querySelector('.hermes-mobile-toggle')) {
            const btn = document.createElement('button');
            btn.className = 'hermes-mobile-toggle';
            btn.textContent = '☰ Tree';
            btn.onclick = () => {
                const sidebar = document.querySelector('.vault-sidebar');
                if (sidebar) sidebar.classList.toggle('open');
            };
            header.insertBefore(btn, header.firstChild);
        }
    };

    // ============================================================
    // Init: wire everything together
    // ============================================================

    HermesCustom.init = function() {
        console.log('[HermesCustom] init');
        HermesCustom.injectResponsiveCSS();
        HermesCustom.responsiveLayout();

        // Hook into obv's loadFile to track current file + re-highlight
        if (typeof window.loadFile === 'function') {
            const originalLoadFile = window.loadFile;
            window.loadFile = function(path) {
                HermesCustom._lastLoadedFile = path;
                const result = originalLoadFile.apply(this, arguments);
                // Re-highlight after content renders
                setTimeout(HermesCustom.highlightCurrentNode, 300);
                return result;
            };
        }

        // Fetch graph data once for highlight logic
        fetch('/api/vault/graph')
            .then(r => r.json())
            .then(data => {
                HermesCustom._graphData = data;
                console.log(`[HermesCustom] Loaded graph: ${data.nodes.length} nodes, ${data.edges.length} edges`);
                HermesCustom.highlightCurrentNode();
            })
            .catch(err => console.warn('[HermesCustom] Graph fetch failed:', err));

        // Click handler + responsive layout (need to wait for Three.js to init)
        setTimeout(() => {
            HermesCustom.setupGraphClickHandler();
        }, 1500);
    };

    // Auto-init when DOM is ready
    if (document.readyState === 'loading') {
        document.addEventListener('DOMContentLoaded', HermesCustom.init);
    } else {
        HermesCustom.init();
    }

})();