// ========== Confirm Dialog ==========
function confirmAction(msg) {
    return confirm(msg || '确定要执行此操作吗？');
}

// ========== Delete with Confirm ==========
function deleteItem(url, msg) {
    if (confirmAction(msg || '确定要删除吗？此操作不可恢复。')) {
        fetch(url, {
            method: 'POST',
            headers: { 'Content-Type': 'application/json' }
        }).then(res => res.json()).then(data => {
            if (data.success) {
                showToast('操作成功', 'success');
                setTimeout(() => location.reload(), 800);
            } else {
                showToast(data.message || '操作失败', 'danger');
            }
        }).catch(() => {
            showToast('网络错误', 'danger');
        });
    }
}

// ========== Toast Notification ==========
function showToast(message, type) {
    type = type || 'success';
    var toastEl = document.createElement('div');
    toastEl.className = 'toast align-items-center text-bg-' + type + ' border-0 show';
    toastEl.setAttribute('role', 'alert');
    toastEl.style.cssText = 'position:fixed;top:24px;right:24px;z-index:9999;min-width:260px;border-radius:16px;box-shadow:-4px -4px 10px rgba(255,255,255,0.8),4px 4px 10px rgba(163,163,200,0.35);';
    toastEl.innerHTML = '<div class="d-flex"><div class="toast-body">' + message + '</div><button type="button" class="btn-close btn-close-white me-2 m-auto" data-bs-dismiss="toast"></button></div>';
    document.body.appendChild(toastEl);
    setTimeout(function() {
        toastEl.remove();
    }, 3000);
}

// ========== Auto-dismiss alerts ==========
document.addEventListener('DOMContentLoaded', function() {
    var alerts = document.querySelectorAll('.alert:not(.alert-permanent)');
    alerts.forEach(function(alert) {
        setTimeout(function() {
            var bsAlert = new bootstrap.Alert(alert);
            bsAlert.close();
        }, 3000);
    });
});

// ========== Sidebar Toggle (mobile) ==========
function toggleSidebar() {
    document.querySelector('.sidebar').classList.toggle('show');
}

// ========== Format Number ==========
function formatNumber(num) {
    if (num === null || num === undefined) return '0';
    return parseFloat(num).toLocaleString('zh-CN', { minimumFractionDigits: 2, maximumFractionDigits: 2 });
}

// ========== Form Validation ==========
(function() {
    'use strict';
    var forms = document.querySelectorAll('.needs-validation');
    forms.forEach(function(form) {
        form.addEventListener('submit', function(event) {
            if (!form.checkValidity()) {
                event.preventDefault();
                event.stopPropagation();
            }
            form.classList.add('was-validated');
        }, false);
    });
})();

// ========== Date Range Picker Helper ==========
function setQuickDateRange(startInput, endInput, days) {
    var end = new Date();
    var start = new Date();
    start.setDate(start.getDate() - days);
    startInput.value = start.toISOString().split('T')[0];
    endInput.value = end.toISOString().split('T')[0];
}

// ========== Export Table to CSV ==========
function exportTableToCSV(tableId, filename) {
    var table = document.getElementById(tableId);
    if (!table) return;
    var rows = table.querySelectorAll('tr');
    var csv = [];
    rows.forEach(function(row) {
        var cols = row.querySelectorAll('td, th');
        var rowData = [];
        cols.forEach(function(col) {
            rowData.push('"' + col.innerText.replace(/"/g, '""') + '"');
        });
        csv.push(rowData.join(','));
    });
    var blob = new Blob(['\uFEFF' + csv.join('\n')], { type: 'text/csv;charset=utf-8;' });
    var link = document.createElement('a');
    link.href = URL.createObjectURL(blob);
    link.download = filename || 'export.csv';
    link.click();
}