// Trial Periods Page Management
// This file handles the standalone trial periods page

let trialPeriodsData = [];
let filteredTrialPeriodsData = [];
let trialCurrentPage = 1;
let trialPageSize = 10;
let trialTotalItems = 0;
let trialTotalPages = 0;
let customersMap = {}; // Map of customer ID to customer name
let trialStartDateFilter = '';
let trialEndDateFilter = '';
let trialSortOrder = 'desc';

// Initialize trial periods page
function initTrialPeriodsPage() {
    const addTrialBtn = document.getElementById('addTrialBtn');
    const trialPeriodsSection = document.getElementById('trialPeriodsSection');

    if (!trialPeriodsSection) return;

    // Add trial button click
    if (addTrialBtn) {
        addTrialBtn.addEventListener('click', function () {
            openAddTrialModal();
        });
    }

    // Pagination controls
    document.getElementById('trialFirstPage')?.addEventListener('click', () => {
        trialCurrentPage = 1;
        applyTrialFiltersAndSort();
    });

    document.getElementById('trialPrevPage')?.addEventListener('click', () => {
        if (trialCurrentPage > 1) {
            trialCurrentPage--;
            applyTrialFiltersAndSort();
        }
    });

    document.getElementById('trialNextPage')?.addEventListener('click', () => {
        if (trialCurrentPage < trialTotalPages) {
            trialCurrentPage++;
            applyTrialFiltersAndSort();
        }
    });

    document.getElementById('trialLastPage')?.addEventListener('click', () => {
        trialCurrentPage = trialTotalPages;
        applyTrialFiltersAndSort();
    });

    document.getElementById('trialPageSizeSelect')?.addEventListener('change', function () {
        trialPageSize = parseInt(this.value);
        trialCurrentPage = 1;
        applyTrialFiltersAndSort();
    });

    // Filter and sort event listeners
    document.getElementById('trialStartDateFilter')?.addEventListener('change', function () {
        trialStartDateFilter = this.value;
        trialCurrentPage = 1;
        applyTrialFiltersAndSort();
    });

    document.getElementById('trialEndDateFilter')?.addEventListener('change', function () {
        trialEndDateFilter = this.value;
        trialCurrentPage = 1;
        applyTrialFiltersAndSort();
    });

    document.getElementById('trialSortOrder')?.addEventListener('change', function () {
        trialSortOrder = this.value;
        trialCurrentPage = 1;
        applyTrialFiltersAndSort();
    });

    // Load customers map for displaying customer names
    loadCustomersMap();
}

// Load customers map for displaying customer names in table
async function loadCustomersMap() {
    try {
        console.log('Loading customers map...');
        const response = await authenticatedFetch('/api/customers/list');

        if (!response) {
            console.error('No response from API');
            return;
        }

        const data = await response.json();
        console.log('Customers data:', data);

        // Use the complete customer map for ID->Name lookups
        customersMap = data.customerMap || {};

        console.log('Number of customer ID mappings:', Object.keys(customersMap).length);
    } catch (error) {
        console.error('Error loading customers map:', error);
    }
}

// Alias for loadCustomersMap - used by main.js when switching to trial periods section
async function loadCustomersForDropdown() {
    return await loadCustomersMap();
}


// Load all trial periods
async function loadAllTrialPeriods() {
    try {
        const response = await authenticatedFetch('/api/trial-periods/all');
        const data = await response.json();

        trialPeriodsData = data.trialPeriods || [];
        applyTrialFiltersAndSort();
        renderExpiryWarnings();
    } catch (error) {
        console.error('Error loading trial periods:', error);
        trialPeriodsData = [];
        filteredTrialPeriodsData = [];
        renderTrialPeriodsTable();
    }
}

// Apply filters and sorting to trial periods
function applyTrialFiltersAndSort() {
    let filtered = [...trialPeriodsData];

    // Apply date range filter
    if (trialStartDateFilter) {
        filtered = filtered.filter(period => {
            const endDate = new Date(period.endTime).toISOString().split('T')[0];
            return endDate >= trialStartDateFilter;
        });
    }

    if (trialEndDateFilter) {
        filtered = filtered.filter(period => {
            const endDate = new Date(period.endTime).toISOString().split('T')[0];
            return endDate <= trialEndDateFilter;
        });
    }

    // Sort by end time
    filtered.sort((a, b) => {
        const dateA = new Date(a.endTime);
        const dateB = new Date(b.endTime);
        return trialSortOrder === 'asc' ? dateA - dateB : dateB - dateA;
    });

    filteredTrialPeriodsData = filtered;
    trialTotalItems = filteredTrialPeriodsData.length;
    trialTotalPages = Math.ceil(trialTotalItems / trialPageSize);

    renderTrialPeriodsTable();
    updateTrialPagination();
}

// Render expiry warning cards
function renderExpiryWarnings() {
    const warningsContainer = document.getElementById('trialExpiryWarnings');
    if (!warningsContainer) return;

    warningsContainer.innerHTML = '';

    const now = new Date();
    now.setHours(0, 0, 0, 0); // Set to start of today

    const warnings = [];

    trialPeriodsData.forEach(period => {
        const endTime = new Date(period.endTime);
        endTime.setHours(0, 0, 0, 0); // Set to start of day

        const daysUntilExpiry = Math.ceil((endTime - now) / (1000 * 60 * 60 * 24));
        const customerName = customersMap[period.customerId] || period.customerId;

        if (daysUntilExpiry >= 0 && daysUntilExpiry <= 3) {
            warnings.push({
                customerName,
                endTime: period.endTime,
                daysUntilExpiry,
                period
            });
        }
    });

    // Sort by days until expiry (most urgent first)
    warnings.sort((a, b) => a.daysUntilExpiry - b.daysUntilExpiry);

    warnings.forEach(warning => {
        const card = document.createElement('div');
        let warningClass = 'warning-soon';
        let iconClass = 'fa-info-circle';
        let title = '试用即将到期';
        let message = '';

        if (warning.daysUntilExpiry === 0) {
            warningClass = 'warning-today';
            iconClass = 'fa-exclamation-triangle';
            title = '试用今日到期';
            message = `<strong>${warning.customerName}</strong> 客户的试用期将于<span class="expiry-warning-time">今天</span>到期，请及时跟进！`;
        } else if (warning.daysUntilExpiry === 1) {
            warningClass = 'warning-tomorrow';
            iconClass = 'fa-exclamation-circle';
            title = '试用明日到期';
            message = `<strong>${warning.customerName}</strong> 客户的试用期将于<span class="expiry-warning-time">明天</span>到期，请及时跟进！`;
        } else {
            warningClass = 'warning-soon';
            iconClass = 'fa-info-circle';
            title = '试用即将到期';
            message = `<strong>${warning.customerName}</strong> 客户的试用期将于<span class="expiry-warning-time">${warning.daysUntilExpiry}天后</span>到期，请及时跟进！`;
        }

        const formattedEndTime = formatDateTime(warning.endTime);
        message += `<br><small>试用结束时间：${formattedEndTime}</small>`;

        card.className = `expiry-warning-card ${warningClass}`;
        card.innerHTML = `
            <div class="expiry-warning-icon">
                <i class="fas ${iconClass}"></i>
            </div>
            <div class="expiry-warning-content">
                <div class="expiry-warning-title">${title}</div>
                <div class="expiry-warning-message">${message}</div>
            </div>
            <button class="expiry-warning-close" onclick="this.parentElement.remove()">
                <i class="fas fa-times"></i>
            </button>
        `;

        warningsContainer.appendChild(card);
    });
}


// Render trial periods table
function renderTrialPeriodsTable() {
    const tbody = document.getElementById('trialPeriodsBody');
    if (!tbody) return;

    tbody.innerHTML = '';

    if (filteredTrialPeriodsData.length === 0) {
        const row = document.createElement('tr');
        row.innerHTML = `
            <td colspan="6" class="empty-state">
                <i class="fas fa-users"></i>
                <h3>👥 还没有客户试用信息</h3>
                <p>点击上方「添加试用时间」开始管理客户试用</p>
            </td>
        `;
        tbody.appendChild(row);
        return;
    }

    // Paginate data
    const startIndex = (trialCurrentPage - 1) * trialPageSize;
    const endIndex = Math.min(startIndex + trialPageSize, filteredTrialPeriodsData.length);
    const pageData = filteredTrialPeriodsData.slice(startIndex, endIndex);

    pageData.forEach(period => {
        const row = document.createElement('tr');
        row.classList.add('trial-row');

        // 显示客户名称，如果找不到则显示ID
        const customerName = customersMap[period.customerId] || period.customerId;

        // 计算状态和到期天数
        const now = new Date();
        const endDate = new Date(period.endTime);
        const startDate = new Date(period.startTime);
        const daysUntilExpiry = Math.ceil((endDate - now) / (1000 * 60 * 60 * 24));
        const isTrial = (period.isTrial !== undefined && period.isTrial !== null) ? period.isTrial : false;

        // 生成状态badge
        let statusBadge = '';
        if (!isTrial) {
            statusBadge = '<span class="status-badge status-inactive"><i class="fas fa-pause-circle"></i> 非试用</span>';
        } else if (daysUntilExpiry < 0) {
            statusBadge = '<span class="status-badge status-expired"><i class="fas fa-times-circle"></i> 已过期</span>';
        } else if (daysUntilExpiry === 0) {
            statusBadge = '<span class="status-badge status-urgent"><i class="fas fa-exclamation-circle"></i> 今日到期</span>';
        } else if (daysUntilExpiry <= 3) {
            statusBadge = `<span class="status-badge status-warning"><i class="fas fa-clock"></i> ${daysUntilExpiry}天后到期</span>`;
        } else if (daysUntilExpiry <= 7) {
            statusBadge = `<span class="status-badge status-notice"><i class="fas fa-bell"></i> ${daysUntilExpiry}天后到期</span>`;
        } else {
            statusBadge = '<span class="status-badge status-active"><i class="fas fa-check-circle"></i> 试用中</span>';
        }

        const startTime = formatDateTime(period.startTime);
        const endTime = formatDateTime(period.endTime);
        const createdAt = formatDateTime(period.createdAt);

        row.innerHTML = `
            <td><strong>${customerName}</strong></td>
            <td>${statusBadge}</td>
            <td>${startTime}</td>
            <td>${endTime}</td>
            <td>${createdAt}</td>
            <td class="action-cell">
                <button class="action-btn edit-btn" data-id="${period.id}" title="编辑">
                    <i class="fas fa-edit"></i>
                </button>
                <button class="action-btn delete-btn" data-id="${period.id}" title="删除">
                    <i class="fas fa-trash"></i>
                </button>
            </td>
        `;

        tbody.appendChild(row);
    });

    // Add event listeners
    tbody.querySelectorAll('.edit-btn').forEach(btn => {
        btn.addEventListener('click', function () {
            const periodId = this.getAttribute('data-id');
            openEditTrialModal(periodId);
        });
    });

    tbody.querySelectorAll('.delete-btn').forEach(btn => {
        btn.addEventListener('click', function () {
            const periodId = this.getAttribute('data-id');
            deleteTrialPeriodFromPage(periodId);
        });
    });
}

// Update trial pagination
function updateTrialPagination() {
    const startItem = trialTotalItems === 0 ? 0 : (trialCurrentPage - 1) * trialPageSize + 1;
    const endItem = Math.min(trialCurrentPage * trialPageSize, trialTotalItems);

    document.getElementById('trialPaginationInfo').textContent =
        `显示 ${startItem}-${endItem} 共 ${trialTotalItems} 条`;

    document.getElementById('trialFirstPage').disabled = trialCurrentPage === 1;
    document.getElementById('trialPrevPage').disabled = trialCurrentPage === 1;
    document.getElementById('trialNextPage').disabled = trialCurrentPage === trialTotalPages;
    document.getElementById('trialLastPage').disabled = trialCurrentPage === trialTotalPages;

    // Update page numbers
    const pageNumbers = document.getElementById('trialPageNumbers');
    pageNumbers.innerHTML = '';

    const maxVisiblePages = 5;
    let startPage = Math.max(1, trialCurrentPage - Math.floor(maxVisiblePages / 2));
    let endPage = Math.min(trialTotalPages, startPage + maxVisiblePages - 1);

    if (endPage - startPage < maxVisiblePages - 1) {
        startPage = Math.max(1, endPage - maxVisiblePages + 1);
    }

    for (let i = startPage; i <= endPage; i++) {
        const pageBtn = document.createElement('button');
        pageBtn.className = 'page-number';
        if (i === trialCurrentPage) {
            pageBtn.classList.add('active');
        }
        pageBtn.textContent = i;
        pageBtn.addEventListener('click', () => {
            trialCurrentPage = i;
            applyTrialFiltersAndSort();
        });
        pageNumbers.appendChild(pageBtn);
    }
}

// Open add trial modal
function openAddTrialModal() {
    console.log('Opening add trial modal');
    document.getElementById('trialCustomerInput').value = '';
    document.querySelector('input[name="isTrial"][value="true"]').checked = true;
    document.getElementById('trialStartTime').value = '';
    document.getElementById('trialEndTime').value = '';
    document.getElementById('addTrialPeriodModal').style.display = 'block';
}

// Open edit trial modal
function openEditTrialModal(periodId) {
    const period = filteredTrialPeriodsData.find(p => p.id === periodId);
    if (!period) return;

    document.getElementById('editTrialPeriodId').value = period.id;

    const startDate = new Date(period.startTime);
    const endDate = new Date(period.endTime);

    document.getElementById('editTrialStartTime').value = formatDateTimeLocal(startDate);
    document.getElementById('editTrialEndTime').value = formatDateTimeLocal(endDate);

    document.getElementById('editTrialPeriodModal').style.display = 'block';
}

// Delete trial period from page
async function deleteTrialPeriodFromPage(periodId) {
    if (!confirm('确定要删除这个试用时间记录吗？')) {
        return;
    }

    try {
        const response = await authenticatedFetch(`/api/trial-periods/${periodId}`, {
            method: 'DELETE'
        });

        if (response.ok) {
            await loadAllTrialPeriods();
            alert('试用时间删除成功！');
        } else {
            alert('删除试用时间时出错');
        }
    } catch (error) {
        console.error('Error deleting trial period:', error);
        alert('删除试用时间时出错');
    }
}

// Create trial period from page
async function createTrialPeriodFromPage() {
    const customerName = document.getElementById('trialCustomerInput').value.trim();
    const isTrialValue = document.querySelector('input[name="isTrial"]:checked').value;
    const isTrial = isTrialValue === 'true';
    const startTime = document.getElementById('trialStartTime').value;
    const endTime = document.getElementById('trialEndTime').value;

    if (!customerName) {
        alert('请输入客户名称');
        return;
    }

    if (!startTime || !endTime) {
        alert('请填写开始时间和结束时间');
        return;
    }

    // Find or create customer ID from customer name
    let customerId = null;
    for (const [id, name] of Object.entries(customersMap)) {
        if (name === customerName) {
            customerId = id;
            break;
        }
    }

    // If customer doesn't exist in map, generate a new ID
    if (!customerId) {
        customerId = customerName; // Use customer name as ID for now
    }

    const formData = {
        customerId: customerId,
        startTime: new Date(startTime).toISOString(),
        endTime: new Date(endTime).toISOString(),
        isTrial: isTrial
    };

    try {
        const response = await authenticatedFetch('/api/trial-periods', {
            method: 'POST',
            headers: {
                'Content-Type': 'application/json'
            },
            body: JSON.stringify(formData)
        });

        if (response.ok) {
            document.getElementById('addTrialPeriodModal').style.display = 'none';
            document.getElementById('addTrialPeriodForm').reset();
            await loadAllTrialPeriods();
            alert('试用时间添加成功！');
        } else {
            alert('添加试用时间时出错');
        }
    } catch (error) {
        console.error('Error creating trial period:', error);
        alert('添加试用时间时出错');
    }
}

// Initialize when switching to trial periods section
document.addEventListener('DOMContentLoaded', function () {
    initTrialPeriodsPage();

    // Override the form submit for add trial period
    const addForm = document.getElementById('addTrialPeriodForm');
    if (addForm) {
        addForm.addEventListener('submit', async function (e) {
            e.preventDefault();
            await createTrialPeriodFromPage();
        });
    }
});