/**
 * AKSRT CMS Download
 *
 * 功能：
 *   - 监听 [data-action="aksrt-download"] 按钮点击
 *   - 调 POST /aksrt/v1/download/request
 *   - 弹窗显示下载链接（含提取码）
 *
 * 依赖：
 *   - window.aksrtData.{ ajaxUrl, nonce, siteUrl }
 *   - 主题已加载 fetch (现代浏览器)
 */
(function () {
	'use strict';

	if (!window.aksrtData) return;
	const REST_BASE = window.aksrtData.siteUrl ? window.aksrtData.siteUrl.replace(/\/$/, '') + '/wp-json/aksrt/v1' : '/wp-json/aksrt/v1';
	const PAY_CONTENT_PATH = '/pay/content/';

	function tt(key, zh) { return zh; }

	function escapeHtml(value) {
		return String(value == null ? '' : value)
			.replace(/&/g, '&')
			.replace(/</g, '&lt;')
			.replace(/>/g, '&gt;')
			.replace(/"/g, '&quot;')
			.replace(/'/g, '&#039;');
	}

	function escapeAttr(value) {
		return escapeHtml(value);
	}

	// ===== Focus trap state =====
	let lastFocusedElement = null;

	function getFocusableElements(container) {
		if (!container) return [];
		return Array.prototype.slice.call(container.querySelectorAll(
			'a[href], area[href], button:not([disabled]), input:not([disabled]):not([type="hidden"]),' +
			' select:not([disabled]), textarea:not([disabled]), [tabindex]:not([tabindex="-1"])'
		)).filter(function (el) {
			return !!(el.offsetWidth || el.offsetHeight || el.getClientRects().length);
		});
	}

	function trapFocus(e, modal) {
		if (e.key !== 'Tab') return;
		const focusables = getFocusableElements(modal);
		if (!focusables.length) {
			e.preventDefault();
			return;
		}
		const first = focusables[0];
		const last = focusables[focusables.length - 1];
		if (e.shiftKey && document.activeElement === first) {
			e.preventDefault();
			last.focus();
		} else if (!e.shiftKey && document.activeElement === last) {
			e.preventDefault();
			first.focus();
		}
	}

	// ===== Modal helper =====
	function buildModal() {
		let modal = document.getElementById('aksrt-dl-modal');
		if (modal) return modal;
		modal = document.createElement('div');
		modal.id = 'aksrt-dl-modal';
		modal.className = 'aksrt-dl-modal';
		modal.setAttribute('role', 'dialog');
		modal.setAttribute('aria-modal', 'true');
		modal.setAttribute('aria-hidden', 'true');
		modal.setAttribute('aria-labelledby', 'aksrt-dl-modal-title');
		modal.innerHTML =
			'<div class="aksrt-dl-modal__backdrop" data-close></div>' +
			'<div class="aksrt-dl-modal__dialog modal-mini">' +
			'  <div class="aksrt-dl-modal__panel modal-content" role="document" tabindex="-1">' +
			'    <button type="button" class="aksrt-dl-modal__close" aria-label="' + tt('close', '关闭') + '" data-close>×</button>' +
			'    <div class="aksrt-dl-modal__body" data-body></div>' +
			'  </div>' +
			'</div>';
		document.body.appendChild(modal);

		modal.addEventListener('click', function (e) {
			if (e.target.closest('[data-close]')) close();
		});
		modal.addEventListener('keydown', function (e) {
			if (e.key === 'Escape' && modal.classList.contains('is-open')) {
				e.preventDefault();
				close();
			} else if (e.key === 'Tab' && modal.classList.contains('is-open')) {
				trapFocus(e, modal);
			}
		});
		return modal;
	}

	function open(html, returnFocusEl, variant) {
		// 记录调用方按钮以便关闭后回焦
		lastFocusedElement = returnFocusEl || document.activeElement;

		const modal = buildModal();
		const body = modal.querySelector('[data-body]');
		modal.classList.toggle('is-cashier', variant === 'cashier');
		body.innerHTML = html;
		const title = body.querySelector('.aksrt-dl-modal__title, .aksrt-cashier__title');
		if (title) title.id = 'aksrt-dl-modal-title';
		modal.classList.add('is-open');
		modal.setAttribute('aria-hidden', 'false');
		document.body.classList.add('aksrt-dl-modal-open');

		// 进入后将焦点放在第一个可聚焦元素，否则放 panel
		setTimeout(function () {
			const focusables = getFocusableElements(modal);
			if (focusables.length) {
				focusables[0].focus();
			} else {
				modal.querySelector('.aksrt-dl-modal__panel').focus();
			}
		}, 0);
	}

	function close() {
		const modal = document.getElementById('aksrt-dl-modal');
		if (!modal) return;
		modal.classList.remove('is-open');
		modal.setAttribute('aria-hidden', 'true');
		document.body.classList.remove('aksrt-dl-modal-open');
		// 焦点回到触发按钮
		if (lastFocusedElement && typeof lastFocusedElement.focus === 'function') {
			try { lastFocusedElement.focus(); } catch (_) { /* ignore */ }
		}
		lastFocusedElement = null;
	}

	// ===== 错误提示渲染 =====
	function renderError(msg, data, returnFocusEl, code) {
		let title = tt('failed', '下载失败');
		let extra = '';

		if (code === 'aksrt_need_login' && data && data.login_url) {
			title = tt('need_login', '请先登录');
			msg = tt('login_hint', '登录后即可继续下载，访客不可使用此资源。');
			extra = '<a class="btn-primary btn-sm" href="' + data.login_url + '">' + tt('go_login', '前往登录') + '</a>';
		} else if (code === 'aksrt_need_purchase') {
			title = tt('need_purchase', '请先购买');
			msg = msg || tt('purchase_hint', '请先完成购买后再下载该资源。');
			extra = '<button type="button" class="btn-primary btn-sm" data-aksrt-open-cashier="' + escapeAttr((data && data.post_id) || '') + '">' + tt('go_buy', '去购买') + '</button>';
		} else if (code === 'aksrt_need_vip') {
			title = tt('need_vip', '会员专属');
			msg = msg || tt('vip_hint', '该资源仅限会员购买/下载。');
			if (data && data.vip_url) {
				extra = '<a class="btn-primary btn-sm" href="' + escapeAttr(data.vip_url) + '">' + tt('go_vip', '开通会员') + '</a>';
			}
		} else if (code === 'aksrt_points_insufficient' || code === 'aksrt_balance_insufficient') {
			title = tt('credit_low', '积分不够');
			const balance = typeof (data && data.balance) === 'number' ? data.balance : 0;
			const cost = typeof (data && data.cost) === 'number' ? data.cost : 0;
			msg = tt('credit_hint',
				'当前余额 ' + balance + ' 积分，需要 ' + cost + ' 积分。可通过签到、阅读、邀请好友等方式获取积分。'
			);
			if (data && data.credits_url) {
				extra = '<a class="btn-primary btn-sm" href="' + escapeAttr(data.credits_url) + '">' + tt('my_points', '我的积分') + '</a>';
			}
		} else if (code === 'aksrt_download_limit') {
			title = tt('quota_over', '今日免费额度已用完');
			msg = msg || tt('quota_hint', '您今日下载免费资源个数已超限，请明日再下载。');
			if (data && data.allow_limit_over && data.post_id) {
				extra = '<button type="button" class="btn-primary btn-sm" data-aksrt-open-cashier="' + escapeAttr(data.post_id) + '" data-price-type="download_limit_over">' + tt('buy_over', '立即购买') + '</button>';
			}
		} else if (code === 'aksrt_captcha_failed') {
			title = tt('captcha_fail', '验证失败');
			msg = msg || tt('captcha_retry', '人机验证失败，请重试。');
		} else if (data && data.login_url) {
			extra = '<a class="btn-primary btn-sm" href="' + data.login_url + '">' + tt('go_login', '前往登录') + '</a>';
		}

		open(
			'<h3 class="aksrt-dl-modal__title">' + title + '</h3>' +
			'<p class="aksrt-dl-modal__msg">' + (msg || '') + '</p>' +
			(extra ? '<div class="aksrt-dl-modal__actions">' + extra + '</div>' : ''),
			returnFocusEl
		);

		const openCashierBtn = document.querySelector('[data-aksrt-open-cashier]');
		if (openCashierBtn) {
			openCashierBtn.addEventListener('click', function () {
				const pid = parseInt(openCashierBtn.getAttribute('data-aksrt-open-cashier'), 10) || 0;
				const pt = openCashierBtn.getAttribute('data-price-type') || '';
				close();
				if (pid) openCashier(pid, returnFocusEl, pt);
			});
		}
	}

	// ===== 成功渲染 =====
	function renderSuccess(payload, returnFocusEl) {
		const code = String(payload.extract_code || '').trim();
		const has = !!payload.has_extract || code !== '';
		const safeCode = escapeHtml(code);
		const safeCodeAttr = escapeAttr(code);
		const dlUrl = escapeAttr(payload.dl_url || '#');
		const extractHtml = code !== ''
			? '<div class="aksrt-dl-modal__row"><span class="aksrt-dl-modal__label">' + tt('extract', '提取码') + '</span><code class="aksrt-dl-modal__code">' + safeCode + '</code><button type="button" class="aksrt-dl-modal__copy" data-copy="' + safeCodeAttr + '"><span class="aksrt-dl-modal__copy-text">' + tt('copy', '复制') + '</span></button></div>'
			: (has ? '<p class="aksrt-dl-modal__msg aksrt-dl-modal__msg--warn">' + tt('extract_missing', '下载源标记了提取码，但接口未返回具体内容，请检查资源下载源的 extract_code 字段。') + '</p>' : '');
		open(
			'<h3 class="aksrt-dl-modal__title">' + tt('ready', '下载已就绪') + '</h3>' +
			(extractHtml || '<p class="aksrt-dl-modal__msg">' + tt('hint', '点击下方按钮开始下载，链接 10 分钟内有效。') + '</p>') +
			'<div class="aksrt-dl-modal__actions">' +
			'  <a class="btn-primary aksrt-dl-modal__download" href="' + dlUrl + '" target="_blank" rel="noopener noreferrer">' + tt('go', '立即下载') + '</a>' +
			(typeof payload.balance === 'number' ? '  <span class="aksrt-dl-modal__balance">' + tt('balance', '余额：') + payload.balance + '</span>' : '') +
			'</div>',
			returnFocusEl
		);

		// 复制按钮
		document.querySelectorAll('[data-copy]').forEach(function (btn) {
			btn.addEventListener('click', function () {
				const text = btn.getAttribute('data-copy') || '';
				const label = btn.querySelector('.aksrt-dl-modal__copy-text') || btn;
				if (navigator.clipboard) {
					navigator.clipboard.writeText(text).then(function () {
						label.textContent = tt('copied', '已复制');
						setTimeout(function () { label.textContent = tt('copy', '复制'); }, 2000);
					});
				}
			});
		});
	}

	// ===== 主流程 =====
	function collectCaptchaPayload(sourceEl) {
		const box = sourceEl ? sourceEl.closest('[data-aksrt-download-box]') : null;
		const container = box ? box.querySelector('[data-aksrt-download-captcha]') : null;
		if (!container) return {};
		const out = {};
		const keys = [
			'captcha_verified',
			'cf_turnstile_response',
			'tencent_ticket', 'tencent_randstr', 'tencent_sid',
			'geetest_lot_number', 'geetest_captcha_output', 'geetest_pass_token', 'geetest_gen_time',
			'aliyun_captcha_verify_param',
		];
		keys.forEach(function (k) {
			const el = container.querySelector('input[name="' + k + '"]');
			if (el && el.value !== '') out[k] = el.value;
		});
		return out;
	}

	function isCaptchaActive(sourceEl) {
		const card = sourceEl ? sourceEl.closest('[data-aksrt-download-box]') : null;
		if (!card) return false;
		return card.getAttribute('data-captcha') === '1';
	}

	function cashierHeader() {
		return '<div class="modal-colorful-header colorful-bg jb-blue">' +
			'<button type="button" class="close aksrt-cashier__close" aria-label="' + tt('close', '关闭') + '" data-close>×</button>' +
			'<div class="colorful-make"></div>' +
			'<div class="text-center">' +
			'  <div class="em2x"><i class="fa fas fa-cart-plus" aria-hidden="true"></i></div>' +
			'  <div class="aksrt-cashier__title mt10 em12 padding-w10">' + tt('confirm_buy', '确认购买') + '</div>' +
			'</div>' +
			'</div>';
	}

	function openCashierContent(content, returnFocusEl) {
		open(
			cashierHeader() + '<div class="modal-pay-body box-body">' + content + '</div>',
			returnFocusEl,
			'cashier'
		);
	}

	function ensureCaptchaThen(sourceEl, callback) {
		if (!isCaptchaActive(sourceEl)) { callback(); return; }
		const state = window.AKSRTCaptchaState;
		const scene = state && state.scenes && state.scenes.download;
		if (!scene || typeof scene.verify !== 'function') {
			// captcha 组件未就绪：不直发，避免绕过服务端门槛
			if (window.console && console.warn) {
				console.warn('[AKSRT] download captcha not ready');
			}
			alert(tt('captcha_loading', '验证码组件加载中，请稍候再试'));
			return;
		}
		scene.verify(function () { callback(); });
	}

	function performDownloadRequest(button) {
		const card = button.closest('[data-aksrt-download-box]');
		if (!card) return;
		const postId = parseInt(card.getAttribute('data-post-id'), 10);
		const sourceIndex = parseInt(button.getAttribute('data-source-index'), 10);
		if (!postId || isNaN(sourceIndex)) return;

		button.disabled = true;
		const original = button.innerHTML;
		button.innerHTML = '<i class="fa fas fa-spinner fa-spin" aria-hidden="true"></i> ' + tt('processing', '处理中…');

		const restNonce = window.aksrtData.restNonce || '';
		const captchaPayload = collectCaptchaPayload(button);

		fetch(REST_BASE + '/download/request', {
			method: 'POST',
			credentials: 'same-origin',
			headers: {
				'Content-Type': 'application/json',
				'X-WP-Nonce': restNonce,
			},
			body: JSON.stringify({
				post_id: postId,
				source_index: sourceIndex,
				captcha: captchaPayload,
			}),
		})
			.then(function (resp) { return resp.json().then(function (j) { return { ok: resp.ok, json: j }; }); })
			.then(function (r) {
				button.disabled = false;
				button.innerHTML = original;
				if (!r.ok || (r.json && r.json.code)) {
					renderError(r.json.message || tt('default_err', '请稍后重试'), r.json.data || {}, button, r.json.code);
					// 验证码已被消费，重置以便用户重试
					try {
						const scene = window.AKSRTCaptchaState && window.AKSRTCaptchaState.scenes && window.AKSRTCaptchaState.scenes.download;
						if (scene && typeof scene.reset === 'function') scene.reset();
					} catch (_) { /* ignore */ }
					return;
				}
				renderSuccess(r.json, button);
			})
			.catch(function () {
				button.disabled = false;
				button.innerHTML = original;
				renderError(tt('network_err', '网络错误，请稍后重试'), {}, button);
			});
	}

	function requestDownload(button) {
		ensureCaptchaThen(button, function () {
			performDownloadRequest(button);
		});
	}

	function pollOrderPaid(orderNumber, returnFocusEl) {
		if (!orderNumber) return;
		let tries = 0;
		const maxTries = 40;
		const timer = setInterval(function () {
			tries += 1;
			fetch(REST_BASE + '/pay/content/order/' + encodeURIComponent(orderNumber), {
				method: 'GET',
				credentials: 'same-origin',
				headers: restHeaders(),
			})
				.then(function (resp) { return resp.json().then(function (j) { return { ok: resp.ok, json: j }; }); })
				.then(function (r) {
					if (r.ok && r.json && r.json.paid) {
						clearInterval(timer);
						window.location.reload();
					}
				})
				.catch(function () { /* ignore */ });
			if (tries >= maxTries) clearInterval(timer);
		}, 3000);
	}

	// ===== 积分不足按钮（前置拦截，不发请求） =====
	function showLowCreditModal(button) {
		const balance = parseInt(button.getAttribute('data-balance'), 10) || 0;
		const cost = parseInt(button.getAttribute('data-cost'), 10) || 0;
		renderError('', { balance: balance, cost: cost }, button, 'aksrt_points_insufficient');
	}

	// ===== 收银台（内容购买） =====
	function restHeaders(idempotencyKey) {
		const headers = {
			'Content-Type': 'application/json',
			'X-WP-Nonce': window.aksrtData.restNonce || '',
		};
		if (idempotencyKey) headers['Idempotency-Key'] = idempotencyKey;
		return headers;
	}

	function buildPreviewUrl(postId, priceType, couponCode) {
		var previewUrl = REST_BASE + PAY_CONTENT_PATH + postId;
		var qs = [];
		if (priceType) qs.push('price_type=' + encodeURIComponent(priceType));
		if (couponCode) qs.push('coupon_code=' + encodeURIComponent(couponCode));
		if (qs.length) previewUrl += '?' + qs.join('&');
		return previewUrl;
	}

	function fetchPreview(postId, priceType, couponCode) {
		return fetch(buildPreviewUrl(postId, priceType, couponCode), {
			method: 'GET',
			credentials: 'same-origin',
			headers: restHeaders(),
		}).then(function (resp) {
			return resp.json().then(function (j) { return { ok: resp.ok, status: resp.status, json: j }; });
		});
	}

	function openCashier(postId, returnFocusEl, priceType, couponCode) {
		if (!postId) return;
		priceType = priceType || '';
		couponCode = couponCode || '';
		openCashierContent(
			'<p class="aksrt-cashier__loading muted-2-color">' + tt('loading', '加载中…') + '</p>',
			returnFocusEl
		);

		fetchPreview(postId, priceType, couponCode)
			.then(function (r) {
				if (!r.ok || (r.json && r.json.code)) {
					const code = r.json && r.json.code ? r.json.code : '';
					const data = (r.json && r.json.data) || {};
					if (code === 'aksrt_need_login' || r.status === 401) {
						renderError(r.json.message || '', data, returnFocusEl, 'aksrt_need_login');
						return;
					}
					if (code === 'aksrt_need_vip') {
						renderError(r.json.message || '', data, returnFocusEl, 'aksrt_need_vip');
						return;
					}
					if (code === 'aksrt_already_paid' || code === 'aksrt_already_followed') {
						window.location.reload();
						return;
					}
					renderError((r.json && r.json.message) || tt('default_err', '请稍后重试'), data, returnFocusEl, code);
					return;
				}
				var prev = r.json || {};
				if (priceType) prev._price_type = priceType;
				if (couponCode) prev._coupon_code = couponCode;
				renderCashier(prev, returnFocusEl);
			})
			.catch(function () {
				renderError(tt('network_err', '网络错误，请稍后重试'), {}, returnFocusEl);
			});
	}

	function formatAssetLabel(preview, value) {
		const currency = escapeHtml(preview.currency || (preview.pay_modo === 'points' ? '积分' : '￥'));
		const amount = escapeHtml(value == null ? '' : value);
		return preview.pay_modo === 'points' ? amount + currency : currency + amount;
	}

	function paymentMethodLogo(methodId) {
		const logoNames = {
			balance: 'pay-balance-logo.svg',
			alipay: 'pay-alipay-logo.svg',
			epay_alipay: 'pay-alipay-logo.svg',
			wechatpay: 'pay-wechat-logo.svg',
			epay_wxpay: 'pay-wechat-logo.svg',
			paypal: 'pay-paypal-logo.svg',
			stripe: 'pay-stripe-logo.svg',
		};
		const logo = logoNames[methodId];
		if (!logo) return '';
		const themeUrl = String(window.aksrtData.themeUrl || '').replace(/\/$/, '');
		return '<img src="' + escapeAttr(themeUrl + '/assets/img/' + logo) + '" alt="">';
	}

	function cashierPriceRow(label, value, className) {
		return '<div class="flex jsb ab aksrt-cashier__price-row">' +
			'<span class="muted-2-color">' + label + '</span>' +
			'<div class="' + (className || '') + '">' + value + '</div>' +
			'</div>';
	}

	function renderCashier(preview, returnFocusEl) {
		if (!preview) return;
		if (preview.need_login && !preview.allow_guest) {
			renderError('', { login_url: preview.login_url }, returnFocusEl, 'aksrt_need_login');
			return;
		}
		if (preview.need_vip) {
			renderError('', { vip_url: preview.vip_url }, returnFocusEl, 'aksrt_need_vip');
			return;
		}
		if (preview.has_paid_access) {
			window.location.reload();
			return;
		}
		// Content free: reload.
		if (preview.is_free) {
			window.location.reload();
			return;
		}

		const isPoints = preview.pay_modo === 'points';
		const priceType = (preview._price_type || preview.price_type || '');

		let amountLabel = escapeHtml(preview.amount_label || '');
		let baseLabel = escapeHtml(preview.base_label || '');
		const listLabel = escapeHtml(preview.list_amount_label || preview.amount_label || amountLabel);
		if (priceType === 'download_limit_over' && preview.download_limit_over_label && !preview.discounts) {
			amountLabel = escapeHtml(preview.download_limit_over_label);
			baseLabel = amountLabel;
			preview.amount = preview.download_limit_over_price;
			preview.base = preview.download_limit_over_price;
		}
		const title = escapeHtml(preview.title || '');
		const typeLabel = escapeHtml(preview.pay_type_label || '');
		const balance = isPoints && Number.isSafeInteger(preview.balance) ? preview.balance : 0;
		const methods = Array.isArray(preview.payment_methods) ? preview.payment_methods : [];
		const couponAllowed = !isPoints && !!preview.coupon_allowed;
		const couponCodeVal = escapeAttr(preview.coupon_code || preview._coupon_code || '');

		let priceRows = '';
		if (!preview.pay_limit) {
			let regularPrice = '<span class="em14">' + baseLabel + '</span>';
			if (!isPoints && Number(preview.original) > Number(preview.base)) {
				regularPrice = '<span class="original-price">' + formatAssetLabel(preview, preview.original) + '</span>' + regularPrice;
			}
			priceRows += cashierPriceRow(tt('price', '价格'), regularPrice, 'aksrt-cashier__regular-price');
		}
		if (preview.list_amount !== preview.base) {
			priceRows += cashierPriceRow(
				tt('vip_price', '会员价') + '<span class="aksrt-cashier__vip-mark">VIP' + escapeHtml(preview.vip_level || '') + '</span>',
				'<span class="em14">' + listLabel + '</span>',
				'c-red'
			);
		} else if (preview.amount !== preview.base && !preview.rebate_discount && !preview.coupon_discount) {
			priceRows += cashierPriceRow(
				tt('vip_price', '会员价') + '<span class="aksrt-cashier__vip-mark">VIP' + escapeHtml(preview.vip_level || '') + '</span>',
				'<span class="em14">' + amountLabel + '</span>',
				'c-red'
			);
		}
		if (preview.rebate_discount > 0) {
			priceRows += cashierPriceRow(
				tt('rebate_discount', '推广折扣'),
				'<span class="em14">' + escapeHtml(preview.rebate_discount_label || ('-' + preview.rebate_discount)) + '</span>'
			);
		}
		if (preview.coupon_discount > 0) {
			priceRows += cashierPriceRow(
				tt('coupon_discount', '优惠码'),
				'<span class="em14">' + escapeHtml(preview.coupon_discount_label || ('-' + preview.coupon_discount)) + '</span>'
			);
		}
		if (preview.amount !== preview.base || preview.rebate_discount > 0 || preview.coupon_discount > 0) {
			priceRows += cashierPriceRow(
				tt('pay_amount', '支付金额'),
				'<span class="em14">' + amountLabel + '</span>',
				'font-bold c-red'
			);
		}

		let body = '';
		body += '<div class="mb10 order-type-' + escapeAttr(preview.pay_type || '') + '">' +
			'<span class="pay-tag badg badg-sm mr6">' + typeLabel + '</span><span>' + title + '</span>' +
			'</div>';
		body += '<div class="mb10 muted-box padding-h6 line-16">' + priceRows + '</div>';

		if (isPoints) {
			body += '<div class="mb10 muted-box padding-h10">' +
				'<div class="flex jsb ac"><span class="muted-2-color">' +
				'<i class="fa fas fa-database aksrt-cashier__asset-icon" aria-hidden="true"></i>' + tt('my_points', '我的积分') +
				'</span><div class="c-green"><span class="em14">' + balance + '</span></div></div></div>';
			if (!preview.balance_enough) {
				body += '<div class="badg c-red btn-block mb20 aksrt-cashier__warn">' + tt('points_short', '抱歉，您的积分不足，暂时无法支付') + '</div>';
				body += '<div class="modal-buts but-average">';
				if (preview.credits_url) {
					body += '<a class="but padding-lg" href="' + escapeAttr(preview.credits_url) + '">' + tt('my_points', '我的积分') + '</a>';
				}
				body += '</div>';
				openCashierContent(body, returnFocusEl);
				return;
			}
			body += '<button type="button" class="mt6 but jb-red initiate-pay btn-block radius" data-aksrt-pay-submit data-mode="points" data-price-type="' + escapeAttr(priceType) + '">' +
				tt('pay_now', '立即支付') + '<span class="pay-price-text ml10">' + amountLabel + '</span></button>';
		} else {
			if (couponAllowed) {
				body += '<div class="mb10 coupon-input-box">';
				body += '<div class="muted-2-color em09 mb6">' + tt('use_coupon', '使用优惠码') + '</div>';
				body += '<div class="relative">';
				body += '<input type="text" class="form-control coupon-input" name="aksrt_coupon_code" value="' + couponCodeVal + '" placeholder="' + escapeAttr(tt('enter_coupon', '请输入优惠码')) + '" autocomplete="off">';
				body += '<span class="abs-right"><button type="button" class="but c-blue coupon-submit" data-aksrt-check-coupon>' + tt('check_coupon', '检查优惠码') + '</button></span>';
				body += '</div>';
				if (preview.coupon_desc) {
					body += '<div class="muted-3-color px12 mt6 aksrt-cashier__coupon-desc">' + escapeHtml(preview.coupon_desc) + '</div>';
				}
				if (preview.coupon_error) {
					body += '<div class="aksrt-cashier__warn">' + escapeHtml(preview.coupon_error) + '</div>';
				} else if (preview.coupon_discount > 0) {
					body += '<div class="aksrt-cashier__coupon-ok">' + tt('coupon_ok', '优惠码可用') + '</div>';
				}
				body += '</div>';
			}
			const walletBal = typeof preview.wallet_balance === 'string'
				? preview.wallet_balance
				: (typeof preview.balance === 'string' ? preview.balance : '0.00');
			const hasBalanceMethod = methods.some(function (m) { return (m && m.id) === 'balance'; });
			let methodHtml = '';
			methods.forEach(function (m, idx) {
				const rawId = String((m && m.id) || '');
				const id = escapeAttr(rawId);
				const name = escapeHtml((m && m.name) || rawId);
				methodHtml += '<div class="flex jc hh payment-method-radio hollow-radio flex-auto pointer' + (idx === 0 ? ' active' : '') + '"' +
					' role="radio" aria-checked="' + (idx === 0 ? 'true' : 'false') + '" tabindex="0" data-aksrt-payment-method="' + id + '">' +
					paymentMethodLogo(rawId) + '<div>' + name + '</div></div>';
			});
			if (methods.length > 1) {
				body += '<div class="muted-2-color em09 mb6">' + tt('pay_method', '请选择支付方式') + '</div>' +
					'<div class="flex mb10 aksrt-cashier__methods" role="radiogroup">' + methodHtml + '</div>';
			}
			if (methods.length) {
				body += '<input type="hidden" name="aksrt_pay_method" value="' + escapeAttr(methods[0].id || '') + '">';
			}
			if (hasBalanceMethod) {
				const balanceSelected = methods[0] && methods[0].id === 'balance';
				body += '<div class="mb10 muted-box padding-h10 aksrt-cashier__balance" data-aksrt-balance-box' + (balanceSelected ? '' : ' hidden') + '>' +
					'<div class="flex jsb ac"><span class="muted-2-color">' +
					'<i class="fa fas fa-wallet aksrt-cashier__asset-icon" aria-hidden="true"></i>' + tt('my_wallet', '我的余额') +
					'</span><div class="c-blue-2"><span class="em14">￥' + escapeHtml(walletBal) + '</span></div></div>';
				if (preview.balance_enough === false) {
					if (preview.credits_url) {
						body += '<a class="but c-red block mt6 aksrt-cashier__recharge" href="' + escapeAttr(preview.credits_url) + '">' +
							tt('wallet_short', '抱歉！余额不足，请先充值') + ' <i class="ml6 fa fa-angle-right em12" aria-hidden="true"></i></a>';
					} else {
						body += '<div class="c-red mt6 aksrt-cashier__recharge">' + tt('wallet_short', '抱歉！余额不足，请先充值') + '</div>';
					}
				}
				body += '</div>';
			}
			if (methods.length) {
				body += '<button type="button" class="mt6 but jb-red initiate-pay btn-block radius" data-aksrt-pay-submit data-mode="cash" data-price-type="' + escapeAttr(priceType) + '">' +
					tt('pay_now', '立即支付') + '<span class="pay-price-text ml10">' + amountLabel + '</span></button>';
			} else {
				body += '<div class="badg c-red btn-block aksrt-cashier__warn">' + tt('no_pay_method', '暂无可用支付方式，请联系站长配置收款接口') + '</div>';
			}
		}

		openCashierContent(body, returnFocusEl);
		const modal = document.getElementById('aksrt-dl-modal');

		const checkBtn = modal && modal.querySelector('[data-aksrt-check-coupon]');
		if (checkBtn) {
			checkBtn.addEventListener('click', function () {
				const input = modal.querySelector('input[name="aksrt_coupon_code"]');
				const code = input ? String(input.value || '').trim() : '';
				if (!code) {
					if (input) input.focus();
					return;
				}
				checkBtn.disabled = true;
				const old = checkBtn.innerHTML;
				checkBtn.innerHTML = tt('checking', '检查中…');
				fetchPreview(preview.post_id, priceType, code)
					.then(function (r) {
						checkBtn.disabled = false;
						checkBtn.innerHTML = old;
						if (!r.ok || (r.json && r.json.code && !r.json.amount && r.json.amount !== 0)) {
							renderError((r.json && r.json.message) || tt('default_err', '请稍后重试'), (r.json && r.json.data) || {}, returnFocusEl, (r.json && r.json.code) || '');
							return;
						}
						var prev = r.json || {};
						if (priceType) prev._price_type = priceType;
						prev._coupon_code = code;
						renderCashier(prev, returnFocusEl);
					})
					.catch(function () {
						checkBtn.disabled = false;
						checkBtn.innerHTML = old;
						renderError(tt('network_err', '网络错误，请稍后重试'), {}, returnFocusEl);
					});
			});
		}

		if (modal) {
			const methodCards = modal.querySelectorAll('[data-aksrt-payment-method]');
			const methodInput = modal.querySelector('input[name="aksrt_pay_method"]');
			const balanceBox = modal.querySelector('[data-aksrt-balance-box]');
			const selectMethod = function (card) {
				const method = card.getAttribute('data-aksrt-payment-method') || '';
				methodCards.forEach(function (item) {
					const active = item === card;
					item.classList.toggle('active', active);
					item.setAttribute('aria-checked', active ? 'true' : 'false');
				});
				if (methodInput) methodInput.value = method;
				if (balanceBox) balanceBox.hidden = method !== 'balance';
			};
			methodCards.forEach(function (card) {
				card.addEventListener('click', function () { selectMethod(card); });
				card.addEventListener('keydown', function (event) {
					if (event.key === 'Enter' || event.key === ' ') {
						event.preventDefault();
						selectMethod(card);
					}
				});
			});
		}

		const submitBtn = modal && modal.querySelector('[data-aksrt-pay-submit]');
		if (submitBtn) {
			submitBtn.addEventListener('click', function () {
				const mode = submitBtn.getAttribute('data-mode') || (isPoints ? 'points' : 'cash');
				let paymentMethod = 'balance';
				const selected = modal.querySelector('input[name="aksrt_pay_method"]');
				if (selected) paymentMethod = selected.value;
				const input = modal.querySelector('input[name="aksrt_coupon_code"]');
				const code = input ? String(input.value || '').trim() : (preview.coupon_code || preview._coupon_code || '');
				submitPurchase(preview.post_id, mode, paymentMethod, submitBtn, returnFocusEl, code);
			});
		}
	}

	function submitPurchase(postId, mode, paymentMethod, button, returnFocusEl, couponCode) {
		if (!postId) return;
		const original = button.innerHTML;
		button.disabled = true;
		button.innerHTML = tt('processing', '处理中…');

		const payload = { mode: mode };
		if (mode === 'cash') payload.payment_method = paymentMethod || 'balance';
		const pt = button.getAttribute('data-price-type') || '';
		if (pt) payload.price_type = pt;
		if (mode === 'cash' && couponCode) payload.coupon_code = couponCode;

		if (!button.dataset.aksrtOperationKey) {
			button.dataset.aksrtOperationKey = window.AksrtRequest.createIdempotencyKey();
		}
		fetch(REST_BASE + PAY_CONTENT_PATH + postId, {
			method: 'POST',
			credentials: 'same-origin',
			headers: restHeaders(button.dataset.aksrtOperationKey),
			body: JSON.stringify(payload),
		})
			.then(function (resp) { return resp.json().then(function (j) { return { ok: resp.ok, status: resp.status, json: j }; }); })
			.then(function (r) {
				button.disabled = false;
				button.innerHTML = original;
				if (!r.ok || (r.json && r.json.code && !r.json.success)) {
					const code = r.json && r.json.code ? r.json.code : '';
					const data = (r.json && r.json.data) || {};
					if (code === 'aksrt_already_paid' || code === 'aksrt_already_followed') {
						window.location.reload();
						return;
					}
					renderError((r.json && r.json.message) || tt('default_err', '请稍后重试'), data, returnFocusEl, code);
					return;
				}
				const data = (r.json && r.json.data) ? r.json.data : r.json;
				delete button.dataset.aksrtOperationKey;
				if (data && data.redirect && (data.payment_url || data.qr_content)) {
					if (data.payment_url) {
						window.open(data.payment_url, '_blank');
					}
					open(
						'<h3 class="aksrt-dl-modal__title">' + tt('scan_pay', '扫码支付') + '</h3>' +
						'<p class="aksrt-dl-modal__msg">' + escapeHtml(data.message || tt('scan_hint', '请使用手机扫码完成支付，支付后刷新页面。')) + '</p>' +
						(data.qr_content ? ('<p class="aksrt-dl-modal__msg"><code>' + escapeHtml(data.qr_content || '') + '</code></p>') : '') +
						'<div class="aksrt-dl-modal__actions"><button type="button" class="btn-primary btn-sm" data-aksrt-reload>' + tt('paid_refresh', '我已支付') + '</button></div>',
						returnFocusEl
					);
					const reloadBtn = document.querySelector('[data-aksrt-reload]');
					if (reloadBtn) reloadBtn.addEventListener('click', function () { window.location.reload(); });
					if (data.order_number) pollOrderPaid(data.order_number, returnFocusEl);
					return;
				}
				window.location.reload();
			})
			.catch(function () {
				button.disabled = false;
				button.innerHTML = original;
				renderError(tt('network_err', '网络错误，请稍后重试'), {}, returnFocusEl);
			});
	}

	// ===== 事件绑定 =====
	document.addEventListener('click', function (e) {
		const lowBtn = e.target.closest('[data-action="aksrt-need-credits"]');
		if (lowBtn) {
			e.preventDefault();
			showLowCreditModal(lowBtn);
			return;
		}

		const buyBtn = e.target.closest('[data-action="aksrt-need-purchase"], [data-aksrt-pay-content]');
		if (buyBtn) {
			e.preventDefault();
			const postId = parseInt(
				buyBtn.getAttribute('data-aksrt-pay-content') ||
				buyBtn.getAttribute('data-post-id') ||
				(buyBtn.closest('[data-post-id]') && buyBtn.closest('[data-post-id]').getAttribute('data-post-id')) ||
				'0',
				10
			);
			const priceType = buyBtn.getAttribute('data-price-type') || '';
			if (postId) openCashier(postId, buyBtn, priceType);
			return;
		}

		const cashierLink = e.target.closest('.cashier-link');
		if (cashierLink && cashierLink.hasAttribute('data-aksrt-pay-content')) {
			e.preventDefault();
			const postId = parseInt(cashierLink.getAttribute('data-aksrt-pay-content') || '0', 10);
			if (postId) openCashier(postId, cashierLink);
			return;
		}

		const btn = e.target.closest('[data-action="aksrt-download"]');
		if (!btn) return;
		if (btn.disabled || btn.getAttribute('aria-disabled') === 'true') return;
		e.preventDefault();
		requestDownload(btn);
	});

	// Public cashier bridge (content pay).
	window.aksrtOpenCashier = function (postId, returnFocusEl, priceType, couponCode) {
		openCashier(postId, returnFocusEl || null, priceType || '', couponCode || '');
	};

})();