{% extends "base.html" %}

{% block title %}问题配置 - 有音个性化教学系统{% endblock %}

{% block page_css %}
<style>
.problem-card { transition: all 0.2s; }
.problem-card:hover { transform: translateY(-2px); box-shadow: 0 4px 15px rgba(0,0,0,0.1); }
.category-badge { font-size: 11px; padding: 3px 8px; }
.category-综合 { background: #f5f5f5; color: #616161; }
.category-乐理相关 { background: #e3f2fd; color: #1565c0; }
.category-演奏能力 { background: #e8f5e9; color: #2e7d32; }
.category-其他 { background: #fff3e0; color: #e65100; }
.editor-textarea { font-family: monospace; font-size: 13px; }
.modal-footer-with-top {
    display: flex;
    justify-content: flex-end;
    gap: 0.5rem;
    padding: 1rem;
    border-top: 1px solid #dee2e6;
    background: #f8f9fa;
    position: sticky;
    bottom: 0;
}
</style>
{% endblock %}

{% block content %}
<!-- Tab导航 -->
<ul class="nav nav-tabs mb-4" id="settingsTabs" role="tablist">
    <li class="nav-item" role="presentation">
        <button class="nav-link active" id="problems-tab" data-bs-toggle="tab" data-bs-target="#problemsPane" type="button">
            <i class="bi bi-list-check"></i> 问题配置
        </button>
    </li>
</ul>

<div class="tab-content" id="settingsTabsContent">
    <!-- 问题配置面板 -->
    <div class="tab-pane fade show active" id="problemsPane" role="tabpanel">
        <!-- 工具栏 -->
        <div class="card mb-3">
            <div class="card-body">
                <div class="d-flex justify-content-between align-items-center mb-3">
                    <h5 class="mb-0"><i class="bi bi-list-check"></i> 问题配置</h5>
                    <div>
                        <button type="button" class="btn btn-outline-secondary btn-sm me-2" onclick="loadProblems()">
                            <i class="bi bi-arrow-clockwise"></i> 刷新
                        </button>
                        <button type="button" class="btn btn-primary btn-sm" onclick="showAddModal()">
                            <i class="bi bi-plus-lg"></i> 新增问题
                        </button>
                    </div>
                </div>
                <input type="text" class="form-control mb-3" placeholder="搜索问题..." id="searchInput" onkeyup="applyProblemFilters()">
                <div class="row g-3 align-items-center">
                    <div class="col-auto">
                        <label class="form-label mb-0">筛选：</label>
                    </div>
                    <div class="col-auto">
                        <select class="form-select" id="filterCategory" onchange="applyProblemFilters()">
                            <option value="">全部分类</option>
                            <option value="综合">综合</option>
                            <option value="乐理相关">乐理相关</option>
                            <option value="演奏能力">演奏能力</option>
                            <option value="其他">其他</option>
                        </select>
                    </div>
                    <div class="col-auto">
                        <label class="form-label mb-0">分组：</label>
                    </div>
                    <div class="col-auto">
                        <select class="form-select" id="groupByCategory" onchange="applyProblemFilters()">
                            <option value="">不分组</option>
                            <option value="category">按分类分组</option>
                        </select>
                    </div>
                    <div class="col-auto ms-auto">
                        <span id="problems-count" class="text-muted small"></span>
                    </div>
                </div>
            </div>
        </div>

        <div class="row" id="problemList"></div>
    </div>
</div>

<!-- 新增问题模态框 -->
<div class="modal fade" id="addModal" tabindex="-1">
    <div class="modal-dialog">
        <div class="modal-content">
            <div class="modal-header">
                <h5 class="modal-title">新增问题</h5>
                <button type="button" class="btn-close" data-bs-dismiss="modal"></button>
            </div>
            <div class="modal-body">
                <div class="mb-3">
                    <label class="form-label">问题编号</label>
                    <input type="text" class="form-control" id="newProblemId" placeholder="如: 16">
                    <small class="text-muted">数字编号，将自动补齐为2位</small>
                </div>
                <div class="mb-3">
                    <label class="form-label">问题名称 *</label>
                    <input type="text" class="form-control" id="newProblemName" placeholder="如: 手小">
                </div>
                <div class="mb-3">
                    <label class="form-label">分类</label>
                    <select class="form-select" id="newProblemCategory">
                        <option value="综合">综合</option>
                        <option value="乐理相关">乐理相关</option>
                        <option value="演奏能力">演奏能力</option>
                        <option value="其他">其他</option>
                    </select>
                </div>
            </div>
            <div class="modal-footer">
                <button type="button" class="btn btn-secondary" data-bs-dismiss="modal">取消</button>
                <button type="button" class="btn btn-primary" onclick="createProblem()">创建</button>
            </div>
        </div>
    </div>
</div>

<!-- 编辑问题模态框 -->
<div class="modal fade" id="editModal" tabindex="-1">
    <div class="modal-dialog modal-lg">
        <div class="modal-content">
            <div class="modal-header">
                <h5 class="modal-title">编辑问题</h5>
                <button type="button" class="btn-close" data-bs-dismiss="modal"></button>
            </div>
            <div class="modal-body">
                <div class="row g-3">
                    <div class="col-md-8">
                        <div class="mb-3">
                            <label class="form-label">问题名称 *</label>
                            <input type="text" class="form-control" id="editProblemName">
                        </div>
                    </div>
                    <div class="col-md-4">
                        <div class="mb-3">
                            <label class="form-label">分类</label>
                            <select class="form-select" id="editProblemCategory">
                                <option value="综合">综合</option>
                                <option value="乐理相关">乐理相关</option>
                                <option value="演奏能力">演奏能力</option>
                                <option value="其他">其他</option>
                            </select>
                        </div>
                    </div>
                </div>
                <div class="mb-3">
                    <label class="form-label">问题描述 (Markdown)</label>
                    <textarea class="form-control editor-textarea" id="editProblemContent" rows="20"></textarea>
                </div>
            </div>
            <div class="modal-footer-with-top">
                <button type="button" class="btn btn-secondary" id="cancelEditProblemBtn">取消</button>
                <button type="button" class="btn btn-primary" onclick="saveProblem()">保存</button>
            </div>
        </div>
    </div>
</div>

<!-- 删除确认模态框 -->
<div class="modal fade" id="deleteModal" tabindex="-1">
    <div class="modal-dialog">
        <div class="modal-content">
            <div class="modal-header">
                <h5 class="modal-title">确认删除</h5>
                <button type="button" class="btn-close" data-bs-dismiss="modal"></button>
            </div>
            <div class="modal-body">
                <p>确定要删除问题 <strong id="deleteProblemName"></strong> 吗？</p>
                <p class="text-muted small">已被学员使用的问题无法删除</p>
            </div>
            <div class="modal-footer">
                <button type="button" class="btn btn-secondary" data-bs-dismiss="modal">取消</button>
                <button type="button" class="btn btn-danger" onclick="confirmDelete()">删除</button>
            </div>
        </div>
    </div>
</div>
{% endblock %}

{% block extra_js %}
    <script>
let allProblems = [];
let currentEditId = null;
let currentDeleteId = null;
const PROBLEM_FILTER_KEY = 'problem_filters';

function saveProblemFilterState() {
    const state = {
        search: document.getElementById('searchInput').value,
        filterCategory: document.getElementById('filterCategory').value,
        groupBy: document.getElementById('groupByCategory').value
    };
    sessionStorage.setItem(PROBLEM_FILTER_KEY, JSON.stringify(state));
}

function restoreProblemFilterState() {
    const saved = sessionStorage.getItem(PROBLEM_FILTER_KEY);
    if (!saved) return;
    try {
        const state = JSON.parse(saved);
        if (state.search) document.getElementById('searchInput').value = state.search;
        if (state.filterCategory) document.getElementById('filterCategory').value = state.filterCategory;
        if (state.groupBy) document.getElementById('groupByCategory').value = state.groupBy;
        saveProblemFilterState();
    } catch (e) {
        console.error('恢复问题筛选状态失败', e);
    }
}

window.pageInit = function() {
    loadProblems();
};

// ========== 问题配置相关 ==========

async function loadProblems() {
    const response = await fetch('/api/problems');
    allProblems = await response.json();
    restoreProblemFilterState();
    applyProblemFilters();
}

function applyProblemFilters() {
    saveProblemFilterState();

    const search = document.getElementById('searchInput').value.toLowerCase();
    const filterCategory = document.getElementById('filterCategory').value;
    const groupBy = document.getElementById('groupByCategory').value;

    // 筛选
    let filtered = allProblems.filter(p => {
        if (search && !p.name.toLowerCase().includes(search)) return false;
        if (filterCategory && p.category !== filterCategory) return false;
        return true;
    });

    // 更新计数
    document.getElementById('problems-count').textContent = `共 ${filtered.length} 个问题`;

    renderProblems(filtered, groupBy);
}

function renderProblems(problems, groupBy) {
    const container = document.getElementById('problemList');
    if (problems.length === 0) {
        container.innerHTML = '<div class="col-12 text-center text-muted py-5"><p>未找到问题配置</p></div>';
        return;
    }

    if (groupBy) {
        // 分组显示
        const groups = {};
        problems.forEach(p => {
            const key = p.category || '其他';
            if (!groups[key]) groups[key] = [];
            groups[key].push(p);
        });

        container.innerHTML = Object.entries(groups).map(([key, items]) => `
            <div class="col-12 mb-3">
                <div class="card">
                    <div class="card-header bg-light">
                        <h6 class="mb-0">分类：${key}（${items.length}个）</h6>
                    </div>
                    <div class="card-body p-2">
                        <div class="row g-2">
                            ${items.map(p => `<div class="col-md-4 col-sm-6">${renderProblemCard(p)}</div>`).join('')}
                        </div>
                    </div>
                </div>
            </div>
        `).join('');
    } else {
        // 不分组
        container.innerHTML = problems.map(p => `
            <div class="col-md-4 col-sm-6 mb-3">
                ${renderProblemCard(p)}
            </div>
        `).join('');
    }
}

function renderProblemCard(p) {
    return `
        <div class="card problem-card h-100">
            <div class="card-body">
                <div class="d-flex justify-content-between align-items-start mb-2">
                    <h6 class="card-title mb-0">${p.name}</h6>
                    <span class="badge category-badge category-${p.category}">${p.category}</span>
                </div>
                <p class="text-muted small mb-2">编号: ${p.id}</p>
                <div class="btn-group btn-group-sm">
                    <button type="button" class="btn btn-outline-primary" onclick="editProblem('${p.id}')">
                        <i class="bi bi-pencil"></i> 编辑
                    </button>
                    <button type="button" class="btn btn-outline-danger" onclick="showDeleteConfirm('${p.id}', '${p.name}')">
                        <i class="bi bi-trash"></i> 删除
                    </button>
                </div>
            </div>
        </div>
    `;
}

// 新增
function showAddModal() {
    document.getElementById('newProblemId').value = '';
    document.getElementById('newProblemName').value = '';
    document.getElementById('newProblemCategory').value = '综合';
    new bootstrap.Modal(document.getElementById('addModal')).show();
}

async function createProblem() {
    const id = document.getElementById('newProblemId').value.trim();
    const name = document.getElementById('newProblemName').value.trim();
    const category = document.getElementById('newProblemCategory').value;

    if (!id || !name) {
        alert('请填写编号和名称');
        return;
    }

    const response = await fetch('/api/problems', {
        method: 'POST',
        headers: {'Content-Type': 'application/json'},
        body: JSON.stringify({id, name, category})
    });

    if (response.ok) {
        bootstrap.Modal.getInstance(document.getElementById('addModal')).hide();
        loadProblems();
    } else {
        const err = await response.json();
        alert(err.error || '创建失败');
    }
}

// 编辑
let editProblemOriginalState = { name: '', content: '' };  // 记录原始状态

async function editProblem(problemId) {
    currentEditId = problemId;
    const response = await fetch(`/api/problems/${problemId}`);
    const data = await response.json();

    if (data.error) {
        alert(data.error);
        return;
    }

    const name = data.name;
    document.getElementById('editProblemName').value = name;
    document.getElementById('editProblemCategory').value = data.category || '综合';
    document.getElementById('editProblemContent').value = data.content || '';

    // 记录原始状态
    editProblemOriginalState.name = name;
    editProblemOriginalState.content = data.content;

    if (window.problemEditor) {
        window.problemEditor.toTextArea();
        window.problemEditor = null;
    }
    if (window.EasyMDE) {
        window.problemEditor = new EasyMDE({
            element: document.getElementById('editProblemContent'),
            spellChecker: false,
            status: false,
            toolbar: ['bold', 'italic', 'heading', '|', 'code', 'quote', 'unordered-list', '|', 'preview', 'side-by-side', 'fullscreen'],
            initialValue: data.content
        });
    }

    const editModal = new bootstrap.Modal(document.getElementById('editModal'), {
        keyboard: false  // 禁用 ESC 关闭，由我们手动处理
    });
    const modalEl = document.getElementById('editModal');

    // 取消按钮点击处理
    document.getElementById('cancelEditProblemBtn').onclick = () => {
        if (isEditProblemDirty()) {
            if (confirm('内容已修改，确定要关闭吗？')) {
                editModal.hide();
            }
        } else {
            editModal.hide();
        }
    };

    // ESC 键处理
    const handleEscape = (e) => {
        if (e.key === 'Escape') {
            e.preventDefault();
            e.stopPropagation();
            if (isEditProblemDirty()) {
                if (confirm('内容已修改，确定要关闭吗？')) {
                    modalEl.removeEventListener('keydown', handleEscape);
                    editModal.hide();
                }
            } else {
                modalEl.removeEventListener('keydown', handleEscape);
                editModal.hide();
            }
        }
    };
    modalEl.addEventListener('keydown', handleEscape);

    editModal.show();
    editModal._element.addEventListener('shown.bs.modal', function() {
        if (window.problemEditor && window.problemEditor.codemirror) {
            window.problemEditor.codemirror.refresh();
        }
    });
}

// 检测编辑问题是否有修改
function isEditProblemDirty() {
    const currentName = document.getElementById('editProblemName').value;
    const currentContent = window.problemEditor ? window.problemEditor.value() : document.getElementById('editProblemContent').value;

    return currentName !== editProblemOriginalState.name || currentContent !== editProblemOriginalState.content;
}

async function saveProblem() {
    const name = document.getElementById('editProblemName').value.trim();
    const category = document.getElementById('editProblemCategory').value;
    const content = window.problemEditor ? window.problemEditor.value() : document.getElementById('editProblemContent').value;

    if (!name) {
        alert('请填写名称');
        return;
    }

    const response = await fetch(`/api/problems/${currentEditId}`, {
        method: 'PUT',
        headers: {'Content-Type': 'application/json'},
        body: JSON.stringify({name, category, content})
    });

    if (response.ok) {
        bootstrap.Modal.getInstance(document.getElementById('editModal')).hide();
        if (window.problemEditor) {
            window.problemEditor.toTextArea();
            window.problemEditor = null;
        }
        loadProblems();
    } else {
        const err = await response.json();
        alert(err.error || '保存失败');
    }
}

// 删除
function showDeleteConfirm(problemId, problemName) {
    currentDeleteId = problemId;
    document.getElementById('deleteProblemName').textContent = problemName;
    new bootstrap.Modal(document.getElementById('deleteModal')).show();
}

async function confirmDelete() {
    const response = await fetch(`/api/problems/${currentDeleteId}`, {
        method: 'DELETE'
    });

    if (response.ok) {
        bootstrap.Modal.getInstance(document.getElementById('deleteModal')).hide();
        loadProblems();
    } else {
        const err = await response.json();
        alert(err.error || '删除失败');
    }
}
</script>
{% endblock %}