(function () {
    // 防止重复初始化
    if (window.contactusFormInitialized) {
        return;
    }
    window.contactusFormInitialized = true;

    // 国家选择器样式（注入一次）
    if (!document.getElementById("cp-style")) {
        const st = document.createElement("style");
        st.id = "cp-style";
        st.textContent = [
            ".country-picker{position:relative;font-size:14px}",
            ".country-picker .cp-display{display:flex;align-items:center;gap:6px;padding:10px;border:1px solid #d1d5db;border-radius:6px;background:#fff;color:#333;cursor:pointer}",
            ".country-picker .cp-search{width:100%;box-sizing:border-box;margin-top:4px;padding:8px 10px;border:1px solid #d1d5db;border-radius:6px;font-size:14px;outline:none}",
            ".country-picker .cp-list{display:none;position:absolute;z-index:99;top:100%;left:0;width:260px;max-height:220px;overflow-y:auto;margin-top:4px;background:#fff;border:1px solid #d1d5db;border-radius:6px;box-shadow:0 8px 24px rgba(0,0,0,.12)}",
            ".country-picker .cp-list.cp-open{display:block}",
            ".country-picker .cp-opt{display:flex;align-items:center;gap:8px;padding:7px 10px;cursor:pointer}",
            ".country-picker .cp-opt:hover{background:#f3f4f6}",
            ".cp-caret{color:#9ca3af;font-size:12px}"
        ].join("");
        (document.head || document.documentElement).appendChild(st);
    }

    const forms = document.querySelectorAll(".contactus-form");
    if (!forms.length) {
        return;
    }

    const DEFAULT_MESSAGES = {
        pending: "Sending your request…",
        success: "Thank you! Our engineering team will contact you within 24 hours.",
        error: "Send failed, please try again later."
    };

    const ensureStatusPlacement = (form, node) => {
        const submitButton = form.querySelector("[type='submit']");
        if (submitButton) {
            if (submitButton.nextElementSibling !== node) {
                submitButton.insertAdjacentElement("afterend", node);
            }
            return;
        }
        if (!node.parentElement) {
            form.appendChild(node);
        }
    };

    const getStatusNode = (form) => {
        let node = form.querySelector(".contactus-status");
        if (!node) {
            node = document.createElement("p");
            node.className = "contactus-status";
            node.setAttribute("role", "status");
            node.setAttribute("aria-live", "polite");
        }
        ensureStatusPlacement(form, node);
        return node;
    };

    const setStatus = (node, state, message) => {
        if (!node) return;
        node.dataset.state = state;
        node.textContent = message || DEFAULT_MESSAGES[state] || "";
    };

    const extractMessage = (payload, fallback) => {
        if (!payload || typeof payload !== "object") {
            return fallback;
        }
        return payload.msg || payload.message || fallback;
    };

    // 全世界国家电话代码 + ISO 国旗代码（默认 +1 美国）
    const COUNTRY_CODES = [
        ["+93", "Afghanistan", "af"], ["+355", "Albania", "al"], ["+213", "Algeria", "dz"],
        ["+376", "Andorra", "ad"], ["+244", "Angola", "ao"], ["+54", "Argentina", "ar"],
        ["+374", "Armenia", "am"], ["+61", "Australia", "au"], ["+43", "Austria", "at"],
        ["+994", "Azerbaijan", "az"], ["+973", "Bahrain", "bh"], ["+880", "Bangladesh", "bd"],
        ["+375", "Belarus", "by"], ["+32", "Belgium", "be"], ["+501", "Belize", "bz"],
        ["+229", "Benin", "bj"], ["+975", "Bhutan", "bt"], ["+591", "Bolivia", "bo"],
        ["+387", "Bosnia and Herzegovina", "ba"], ["+267", "Botswana", "bw"],
        ["+55", "Brazil", "br"], ["+673", "Brunei", "bn"], ["+359", "Bulgaria", "bg"],
        ["+226", "Burkina Faso", "bf"], ["+257", "Burundi", "bi"], ["+855", "Cambodia", "kh"],
        ["+237", "Cameroon", "cm"], ["+1", "Canada", "ca"], ["+238", "Cape Verde", "cv"],
        ["+236", "Central African Republic", "cf"], ["+235", "Chad", "td"], ["+56", "Chile", "cl"],
        ["+86", "China", "cn"], ["+57", "Colombia", "co"], ["+269", "Comoros", "km"],
        ["+242", "Congo", "cg"], ["+243", "Congo (DRC)", "cd"], ["+506", "Costa Rica", "cr"],
        ["+225", "Cote d'Ivoire", "ci"], ["+385", "Croatia", "hr"], ["+53", "Cuba", "cu"],
        ["+357", "Cyprus", "cy"], ["+420", "Czech Republic", "cz"], ["+45", "Denmark", "dk"],
        ["+253", "Djibouti", "dj"], ["+593", "Ecuador", "ec"], ["+20", "Egypt", "eg"],
        ["+503", "El Salvador", "sv"], ["+240", "Equatorial Guinea", "gq"],
        ["+291", "Eritrea", "er"], ["+372", "Estonia", "ee"], ["+268", "Eswatini", "sz"],
        ["+251", "Ethiopia", "et"], ["+679", "Fiji", "fj"], ["+358", "Finland", "fi"],
        ["+33", "France", "fr"], ["+241", "Gabon", "ga"], ["+220", "Gambia", "gm"],
        ["+995", "Georgia", "ge"], ["+49", "Germany", "de"], ["+233", "Ghana", "gh"],
        ["+30", "Greece", "gr"], ["+502", "Guatemala", "gt"], ["+224", "Guinea", "gn"],
        ["+245", "Guinea-Bissau", "gw"], ["+592", "Guyana", "gy"], ["+509", "Haiti", "ht"],
        ["+504", "Honduras", "hn"], ["+852", "Hong Kong", "hk"], ["+36", "Hungary", "hu"],
        ["+354", "Iceland", "is"], ["+91", "India", "in"], ["+62", "Indonesia", "id"],
        ["+98", "Iran", "ir"], ["+964", "Iraq", "iq"], ["+353", "Ireland", "ie"],
        ["+972", "Israel", "il"], ["+39", "Italy", "it"], ["+81", "Japan", "jp"],
        ["+962", "Jordan", "jo"], ["+7", "Kazakhstan", "kz"], ["+254", "Kenya", "ke"],
        ["+686", "Kiribati", "ki"], ["+850", "Korea (North)", "kp"], ["+82", "Korea (South)", "kr"],
        ["+965", "Kuwait", "kw"], ["+996", "Kyrgyzstan", "kg"], ["+856", "Laos", "la"],
        ["+371", "Latvia", "lv"], ["+961", "Lebanon", "lb"], ["+266", "Lesotho", "ls"],
        ["+231", "Liberia", "lr"], ["+218", "Libya", "ly"], ["+423", "Liechtenstein", "li"],
        ["+370", "Lithuania", "lt"], ["+352", "Luxembourg", "lu"], ["+853", "Macau", "mo"],
        ["+261", "Madagascar", "mg"], ["+265", "Malawi", "mw"], ["+60", "Malaysia", "my"],
        ["+960", "Maldives", "mv"], ["+223", "Mali", "ml"], ["+356", "Malta", "mt"],
        ["+692", "Marshall Islands", "mh"], ["+222", "Mauritania", "mr"],
        ["+230", "Mauritius", "mu"], ["+52", "Mexico", "mx"], ["+691", "Micronesia", "fm"],
        ["+373", "Moldova", "md"], ["+377", "Monaco", "mc"], ["+976", "Mongolia", "mn"],
        ["+382", "Montenegro", "me"], ["+212", "Morocco", "ma"], ["+258", "Mozambique", "mz"],
        ["+95", "Myanmar", "mm"], ["+264", "Namibia", "na"], ["+674", "Nauru", "nr"],
        ["+977", "Nepal", "np"], ["+31", "Netherlands", "nl"], ["+64", "New Zealand", "nz"],
        ["+505", "Nicaragua", "ni"], ["+227", "Niger", "ne"], ["+234", "Nigeria", "ng"],
        ["+389", "North Macedonia", "mk"], ["+47", "Norway", "no"], ["+968", "Oman", "om"],
        ["+92", "Pakistan", "pk"], ["+680", "Palau", "pw"], ["+507", "Panama", "pa"],
        ["+675", "Papua New Guinea", "pg"], ["+595", "Paraguay", "py"], ["+51", "Peru", "pe"],
        ["+63", "Philippines", "ph"], ["+48", "Poland", "pl"], ["+351", "Portugal", "pt"],
        ["+974", "Qatar", "qa"], ["+40", "Romania", "ro"], ["+7", "Russia", "ru"],
        ["+250", "Rwanda", "rw"], ["+685", "Samoa", "ws"], ["+378", "San Marino", "sm"],
        ["+239", "Sao Tome and Principe", "st"], ["+966", "Saudi Arabia", "sa"],
        ["+221", "Senegal", "sn"], ["+381", "Serbia", "rs"], ["+248", "Seychelles", "sc"],
        ["+232", "Sierra Leone", "sl"], ["+65", "Singapore", "sg"], ["+421", "Slovakia", "sk"],
        ["+386", "Slovenia", "si"], ["+677", "Solomon Islands", "sb"],
        ["+252", "Somalia", "so"], ["+27", "South Africa", "za"], ["+211", "South Sudan", "ss"],
        ["+34", "Spain", "es"], ["+94", "Sri Lanka", "lk"], ["+249", "Sudan", "sd"],
        ["+597", "Suriname", "sr"], ["+46", "Sweden", "se"], ["+41", "Switzerland", "ch"],
        ["+963", "Syria", "sy"], ["+886", "Taiwan", "tw"], ["+992", "Tajikistan", "tj"],
        ["+255", "Tanzania", "tz"], ["+66", "Thailand", "th"], ["+670", "Timor-Leste", "tl"],
        ["+228", "Togo", "tg"], ["+676", "Tonga", "to"], ["+1", "Trinidad and Tobago", "tt"],
        ["+216", "Tunisia", "tn"], ["+90", "Turkey", "tr"], ["+993", "Turkmenistan", "tm"],
        ["+256", "Uganda", "ug"], ["+380", "Ukraine", "ua"], ["+971", "United Arab Emirates", "ae"],
        ["+44", "United Kingdom", "gb"], ["+1", "United States", "us"], ["+598", "Uruguay", "uy"],
        ["+998", "Uzbekistan", "uz"], ["+678", "Vanuatu", "vu"], ["+58", "Venezuela", "ve"],
        ["+84", "Vietnam", "vn"], ["+967", "Yemen", "ye"], ["+260", "Zambia", "zm"],
        ["+263", "Zimbabwe", "zw"]
    ];

    // 可搜索国家选择器：搜索框 + 国旗 + 代码，选中后写入隐藏 input[name=phone_code]
    const buildCountryPicker = (form) => {
        const host = form.querySelector(".country-picker[data-name='phone_code']");
        if (!host || host.dataset.built) return;
        host.dataset.built = "1";

        const hidden = document.createElement("input");
        hidden.type = "hidden";
        hidden.name = "phone_code";
        hidden.value = "+1";
        host.appendChild(hidden);

        const display = document.createElement("div");
        display.className = "cp-display";
        display.innerHTML = '<img src="https://flagcdn.com/w20/us.png" alt="" loading="lazy" style="width:20px;height:14px;object-fit:cover;border-radius:2px;vertical-align:middle"> <span class="cp-code">+1</span> <span class="cp-caret">▾</span>';
        host.appendChild(display);

        const search = document.createElement("input");
        search.type = "text";
        search.className = "cp-search";
        search.placeholder = "Search country / code";
        search.autocomplete = "off";
        host.appendChild(search);

        const list = document.createElement("div");
        list.className = "cp-list";
        host.appendChild(list);

        const renderList = (q) => {
            q = (q || "").toLowerCase().replace(/^\+/, "");
            list.innerHTML = "";
            COUNTRY_CODES.forEach(([code, name, a2]) => {
                if (q && name.toLowerCase().indexOf(q) === -1 && code.replace("+", "").indexOf(q) === -1) return;
                const row = document.createElement("div");
                row.className = "cp-opt";
                row.innerHTML = '<img src="https://flagcdn.com/w20/' + a2 + '.png" alt="" loading="lazy" style="width:20px;height:14px;object-fit:cover;border-radius:2px;vertical-align:middle"> <span>' + name + '</span> <span style="margin-left:auto;color:#6b7280">' + code + '</span>';
                row.addEventListener("mousedown", (ev) => {
                    ev.preventDefault();
                    hidden.value = code;
                    display.querySelector(".cp-code").textContent = code;
                    display.querySelector("img").src = "https://flagcdn.com/w20/" + a2 + ".png";
                    list.classList.remove("cp-open");
                    search.value = "";
                    search.blur();
                });
                list.appendChild(row);
            });
        };

        display.addEventListener("click", () => {
            list.classList.toggle("cp-open");
            if (list.classList.contains("cp-open")) {
                search.focus();
                renderList("");
            }
        });
        search.addEventListener("input", () => renderList(search.value));
        search.addEventListener("focus", () => {
            list.classList.add("cp-open");
            renderList(search.value);
        });
        document.addEventListener("click", (e) => {
            if (!host.contains(e.target)) list.classList.remove("cp-open");
        });
        renderList("");
    };

    const flagEmailIfNeeded = (form, message) => {
        if (!message) return;
        const normalized = message.toLowerCase();
        if (!normalized.includes("email")) {
            return;
        }
        const emailField = form.querySelector("input[name='email']");
        if (!emailField) {
            return;
        }
        emailField.setAttribute("aria-invalid", "true");
        emailField.focus();
        const clearInvalid = () => {
            emailField.removeAttribute("aria-invalid");
            emailField.removeEventListener("input", clearInvalid);
        };
        emailField.addEventListener("input", clearInvalid);
    };

    const toggleButton = (button, disabled) => {
        if (!button) return;
        if (disabled) {
            // 保存原始文本（如果还没有保存）
            if (!button.dataset.originalText) {
                button.dataset.originalText = button.textContent;
            }
            // 也保存当前文本作为 previousText（用于兼容）
            button.dataset.previousText = button.textContent;
            // 从按钮的 data-submitting 属性读取多语言文本，如果没有则使用默认值
            const submittingText = button.dataset.submitting || "Submitting...";
            button.textContent = submittingText;
            button.setAttribute("disabled", "disabled");
        } else {
            // 优先使用 previousText，如果没有则使用 originalText
            const restoreText = button.dataset.previousText || button.dataset.originalText;
            if (restoreText) {
                button.textContent = restoreText;
            }
            button.removeAttribute("disabled");
            // 清除 previousText，但保留 originalText 以备下次使用
            delete button.dataset.previousText;
        }
    };

    const buildRequest = (form) => {
        const target = form.getAttribute("action") || "/Contactus";
        const formData = new FormData(form);
        if (!formData.get("source") && form.dataset.contactusSource) {
            formData.set("source", form.dataset.contactusSource);
        }
        // 自动采集 page_url: 当前页面路径（含 query）
        if (!formData.get("page_url")) {
            formData.set("page_url", window.location.pathname + window.location.search);
        }
        // form_position: 优先 data-form-position，回退到 source
        if (!formData.get("form_position")) {
            formData.set("form_position", form.dataset.formPosition || formData.get("source") || "unknown");
        }
        return { target, body: formData };
    };

    const handleSubmit = async (event) => {
        event.preventDefault();
        event.stopPropagation(); // 防止事件冒泡导致重复提交
        
        const form = event.currentTarget;
        const submitButton = form.querySelector("[type='submit']");
        const statusNode = getStatusNode(form);

        // 如果按钮已经被禁用，说明正在提交中，直接返回
        if (submitButton && submitButton.disabled) {
            return;
        }

        // ── 前端校验：电话（国家代码+号码，必填）与数量（必选）──
        const phoneCode = (form.querySelector("input[name='phone_code']") || {}).value || "";
        const phoneNum = ((form.querySelector("input[name='phone']") || {}).value || "").trim();
        if (!/^\+\d{1,4}$/.test(phoneCode)) {
            setStatus(statusNode, "error", "Please select your country code");
            const picker = form.querySelector(".country-picker");
            if (picker) picker.scrollIntoView({ block: "center" });
            return;
        }
        if (!/^[\d\s\-()]{4,20}$/.test(phoneNum)) {
            setStatus(statusNode, "error", "Please enter a valid phone number");
            const inp = form.querySelector("input[name='phone']");
            if (inp) inp.focus();
            return;
        }
        const qty = (form.querySelector("select[name='quantity']") || {}).value || "";
        if (qty === "") {
            setStatus(statusNode, "error", "Please select the estimated order quantity");
            const qs = form.querySelector("select[name='quantity']");
            if (qs) qs.focus();
            return;
        }

        // 保存按钮的原始文本
        if (!submitButton.dataset.originalText) {
            submitButton.dataset.originalText = submitButton.textContent;
        }

        setStatus(statusNode, "pending");
        toggleButton(submitButton, true);

        const { target, body } = buildRequest(form);

        try {
            const response = await fetch(target, {
                method: "POST",
                headers: {
                    "X-Requested-With": "XMLHttpRequest"
                },
                body
            });

            let payload = null;
            try {
                payload = await response.json();
            } catch (jsonError) {
                // 如果响应不是有效的 JSON，payload 保持为 null
                console.warn("Response is not valid JSON:", jsonError);
            }

            const serverMessage = extractMessage(payload, DEFAULT_MESSAGES.error);

            if (!response.ok || !payload) {
                throw new Error(serverMessage || "Unexpected server response.");
            }

            if (Number(payload.code) === 200) {
                setStatus(statusNode, "success", serverMessage || payload.msg);
                form.reset();
                form.querySelectorAll("[aria-invalid='true']").forEach((input) => {
                    input.removeAttribute("aria-invalid");
                });
                // Reset file name display if exists
                const fileInput = form.querySelector('input[type="file"]');
                if (fileInput) {
                    const fileNameDisplay = fileInput.closest('.form-file-upload')?.querySelector('.form-file-name') ||
                                            fileInput.closest('.contact-modal__field')?.querySelector('.form-file-name');
                    if (fileNameDisplay) {
                        const placeholder = fileInput.dataset.placeholder || fileNameDisplay.textContent;
                        fileNameDisplay.textContent = placeholder;
                    }
                }
                // GA4 转化追踪
                if (typeof window.gtag === 'function') {
                    window.gtag('event', 'generate_lead', {
                        event_category: 'Inquiry',
                        event_label: 'Form Submission Success'
                    });
                }
                // 跳转到 Thank You 页面
                setTimeout(function () {
                    window.location.href = '/thank-you';
                }, 800);
            } else {
                setStatus(statusNode, "error", serverMessage);
                flagEmailIfNeeded(form, serverMessage);
            }
        } catch (error) {
            const fallbackMessage = error && error.message ? error.message : DEFAULT_MESSAGES.error;
            setStatus(statusNode, "error", fallbackMessage);
            flagEmailIfNeeded(form, fallbackMessage);
        } finally {
            // 确保在所有情况下都恢复按钮状态
            toggleButton(submitButton, false);
        }
    };

    // 为每个表单绑定事件监听器，但先移除可能存在的旧监听器
    forms.forEach((form) => {
        buildCountryPicker(form);
        // 移除可能存在的旧事件监听器（通过克隆节点来移除所有事件监听器）
        // 或者使用 once 选项，但更好的方法是检查是否已经绑定
        if (!form.dataset.contactusBound) {
            form.addEventListener("submit", handleSubmit);
            form.dataset.contactusBound = "true";
        }
    });
})();