const PageScene = {
    _el: null,
    _currentGameId: null,
    _currentGameName: '',
    _editorSceneId: null,
    _editorData: null,

    init() {
        this._el = document.getElementById('page-scene');
    },

    async render() {
        const cfg = await API.getConfig();
        this._currentGameId = cfg.selected_game_id;

        if (this._currentGameId) {
            const games = await API.getGames();
            const game = games.find(g => g.id === this._currentGameId);
            this._currentGameName = game ? game.name : this._currentGameId;
        }

        this._el.innerHTML = this._template();
        await this._loadScenes();
        this._bindEvents();
    },

    async _loadScenes() {
        const grid = document.getElementById('scene-grid');
        if (!grid) return;

        try {
            const scenes = await API.getScenes(this._currentGameId);
            if (!scenes || scenes.length === 0) {
                grid.innerHTML = `
                <div class="empty-state" style="grid-column:1/-1;">
                    <svg viewBox="0 0 24 24" width="64" height="64"><path d="M3 3h8v8H3zm10 0h8v8h-8zM3 13h8v8H3zm10 0h8v8h-8z" fill="currentColor"/></svg>
                    <h4>暂无场景</h4>
                    <p>点击"新建场景"创建你的第一个场景布局</p>
                </div>`;
                return;
            }

            grid.innerHTML = scenes.map(s => this._sceneCardHtml(s)).join('');
        } catch (e) {
            console.error('Failed to load scenes:', e);
        }
    },

    _bindEvents() {
        document.getElementById('btn-new-scene')?.addEventListener('click', () => this._showEditor());
        document.getElementById('btn-import-scene')?.addEventListener('click', () => {
            const input = document.createElement('input');
            input.type = 'file';
            input.accept = '.tss';
            input.onchange = async (e) => {
                const file = e.target.files[0];
                if (!file) return;
                const formData = new FormData();
                formData.append('file', file);
                try {
                    const res = await fetch('/api/scenes/import', { method: 'POST', body: formData });
                    const data = await res.json();
                    if (data.ok) { Toast.show('场景导入成功', 'success'); this._loadScenes(); }
                    else Toast.show('导入失败', 'error');
                } catch (err) { Toast.show('导入失败', 'error'); }
            };
            input.click();
        });

        const grid = document.getElementById('scene-grid');
        if (grid) {
            grid.addEventListener('click', (e) => {
                const card = e.target.closest('[data-scene-id]');
                if (!card) return;
                const action = card.dataset.action;
                const sceneId = card.dataset.sceneId;

                if (action === 'render') {
                    this._renderScene(sceneId);
                } else if (action === 'edit') {
                    e.stopPropagation();
                    this._showEditor(sceneId);
                } else if (action === 'delete') {
                    e.stopPropagation();
                    this._deleteScene(sceneId);
                } else if (action === 'export') {
                    e.stopPropagation();
                    this._exportScene(sceneId);
                }
            });
        }
    },

    async _showEditor(sceneId) {
        let scene = null;
        if (sceneId) {
            scene = await API.getScene(sceneId);
            if (!scene) return;
        }

        this._editorSceneId = sceneId;
        const modal = document.createElement('div');
        modal.className = 'modal-overlay';
        modal.innerHTML = this._editorTemplate(scene);
        document.body.appendChild(modal);

        modal.querySelector('.modal-overlay, .modal-actions .btn-secondary')
            ?.addEventListener('click', (e) => {
                if (e.target === modal || e.target.matches('.btn-secondary')) {
                    modal.remove();
                }
            });

        modal.querySelector('.btn-primary')?.addEventListener('click', async () => {
            const name = modal.querySelector('#edit-scene-name').value || 'New Scene';
            const desc = modal.querySelector('#edit-scene-desc').value || '';
            const gameId = this._currentGameId || '';

            const data = { name, description: desc, game_id: gameId };
            if (this._editorSceneId) {
                await API.updateScene(this._editorSceneId, data);
            } else {
                await API.createScene(data);
            }
            modal.remove();
            Toast.show('场景保存成功', 'success');
            this.render();
        });
    },

    async _renderScene(sceneId) {
        const url = `${location.origin}/scene/${sceneId}`;
        window.open(url, '_blank');
        navigator.clipboard.writeText(url).then(() => {
            Toast.show('场景链接已复制，可在局域网设备访问', 'success');
        }).catch(() => {});
    },

    async _deleteScene(sceneId) {
        if (!confirm('确定删除此场景？')) return;
        await API.deleteScene(sceneId);
        Toast.show('场景已删除', 'info');
        this._loadScenes();
    },

    _exportScene(sceneId) {
        const a = document.createElement('a');
        a.href = `/api/scenes/${sceneId}/export`;
        a.download = `${sceneId}.tss`;
        a.click();
        Toast.show('正在下载 .tss 文件...', 'info');
    },

    _sceneCardHtml(scene) {
        const canvasCount = (scene.canvases || []).length;
        return `
        <div class="glass-card scene-card" data-scene-id="${scene.id}" data-action="render">
            <div class="scene-card-name">${scene.name}</div>
            <div class="scene-card-game" style="margin-bottom:6px;">${this._currentGameName || '未关联游戏'}</div>
            <div class="scene-card-meta">
                <span>${canvasCount} 个画布</span>
                <span>${scene.updated_at ? new Date(scene.updated_at).toLocaleDateString() : ''}</span>
            </div>
            <div class="scene-canvas-list">
                ${(scene.canvases || []).map(c => `<span class="scene-canvas-badge">${c.label || c.width + 'x' + c.height}</span>`).join('')}
            </div>
            <div style="margin-top:12px;display:flex;gap:6px;">
                <button class="btn btn-sm btn-primary" data-scene-id="${scene.id}" data-action="render">渲染</button>
                <button class="btn btn-sm btn-secondary" data-scene-id="${scene.id}" data-action="edit">编辑</button>
                <button class="btn btn-sm btn-secondary" data-scene-id="${scene.id}" data-action="export">导出</button>
                <button class="btn btn-sm btn-danger" data-scene-id="${scene.id}" data-action="delete">删除</button>
            </div>
        </div>`;
    },

    _editorTemplate(scene) {
        const name = scene ? scene.name : '';
        const desc = scene ? scene.description : '';
        return `
        <div class="modal">
            <h3>${scene ? '编辑场景' : '新建场景'}</h3>
            <div class="form-group">
                <label>场景名称</label>
                <input id="edit-scene-name" type="text" value="${name}" placeholder="输入场景名称">
            </div>
            <div class="form-group">
                <label>描述</label>
                <textarea id="edit-scene-desc" placeholder="场景描述（可选）">${desc}</textarea>
            </div>
            <p style="font-size:12px;color:var(--text-tertiary);margin-top:8px;">
                提示：保存后可在场景编辑器中添加仪表盘、调整布局和画布比例。
            </p>
            <div class="modal-actions">
                <button class="btn btn-secondary">取消</button>
                <button class="btn btn-primary">保存</button>
            </div>
        </div>`;
    },

    _template() {
        return `
        <div class="scene-header animated">
            <div>
                <h2>场景管理</h2>
                <p style="color:var(--text-secondary);font-size:14px;margin-top:4px;">
                    ${this._currentGameId ? `当前游戏: ${this._currentGameName}` : '请先在侧边栏选择一个游戏'}
                </p>
            </div>
            <div style="display:flex;gap:8px;">
                <button id="btn-import-scene" class="btn btn-secondary btn-sm">导入 .tss</button>
                <button id="btn-new-scene" class="btn btn-primary btn-sm" ${!this._currentGameId ? 'disabled' : ''}>
                    + 新建场景
                </button>
            </div>
        </div>
        <div id="scene-grid" class="scene-grid animated"></div>`;
    }
};

window.PageScene = PageScene;