(function () {
    var mask = document.getElementById("loginDialog");
    if (!mask) return;

    var form = mask.querySelector("[data-login-dialog-form]");
    var accountInput = mask.querySelector("[data-login-account]");
    var passwordInput = mask.querySelector("[data-login-password]");
    var submitBtn = mask.querySelector("[data-login-submit]");
    var defaultSubmitText = (submitBtn && submitBtn.textContent) || "登录";

    function setSubmitting(loading) {
        if (!submitBtn) return;
        submitBtn.disabled = !!loading;
        submitBtn.classList.toggle("is-loading", !!loading);
        submitBtn.setAttribute("aria-busy", loading ? "true" : "false");
        submitBtn.textContent = loading ? "登录中..." : defaultSubmitText;
    }

    function getField(name) {
        return mask.querySelector('[data-login-field="' + name + '"]');
    }

    function setFieldError(name, message) {
        var field = getField(name);
        if (!field) return;
        var control = field.querySelector("[data-login-control]");
        var error = field.querySelector("[data-login-error]");
        if (control) control.classList.add("is-error");
        if (error) {
            error.textContent = message;
            error.hidden = false;
        }
    }

    function clearFieldError(name) {
        var field = getField(name);
        if (!field) return;
        var control = field.querySelector("[data-login-control]");
        var error = field.querySelector("[data-login-error]");
        if (control) control.classList.remove("is-error");
        if (error) error.hidden = true;
    }

    function clearAllErrors() {
        clearFieldError("account");
        clearFieldError("password");
    }

    function isValidLength(value) {
        return value.length >= 4 && value.length <= 16;
    }

    function validateForm() {
        var account = (accountInput && accountInput.value.trim()) || "";
        var password = (passwordInput && passwordInput.value) || "";
        var valid = true;

        clearAllErrors();

        if (!account) {
            setFieldError("account", "账号格式不正确，请输入有效账号");
            valid = false;
        } else if (!window.AuthAPI || !AuthAPI.isValidLoginAccount(account)) {
            setFieldError("account", "账号格式不正确，请输入有效账号");
            valid = false;
        }

        if (!password) {
            setFieldError("password", "密码错误，请检查后重新输入");
            valid = false;
        } else if (!isValidLength(password)) {
            setFieldError("password", "密码错误，请检查后重新输入");
            valid = false;
        }

        if (!valid) return null;
        return { account: account, password: password };
    }

    function mapServerError(err) {
        var tip = (err && err.message) || "登录失败，请稍后重试";
        if (/密码|password/i.test(tip)) {
            setFieldError("password", tip);
            return;
        }
        if (/账号|账户|用户|邮箱|account|email|不存在|错误/i.test(tip)) {
            setFieldError("account", tip);
            return;
        }
        if (window.AuthAPI) AuthAPI.toast(tip, "error");
        else if (typeof showToast === "function") showToast(tip, "error");
    }

    function openDialog(event) {
        if (event) event.preventDefault();
        if (typeof window.closeRegisterDialog === "function") {
            window.closeRegisterDialog();
        }
        clearAllErrors();
        mask.classList.add("is-open");
        document.body.style.overflow = "hidden";
        return true;
    }

    function closeDialog() {
        mask.classList.remove("is-open");
        clearAllErrors();
        if (!document.getElementById("registerDialog") || !document.getElementById("registerDialog").classList.contains("is-open")) {
            document.body.style.overflow = "";
        }
    }

    function setLoginErrors(errors) {
        clearAllErrors();
        if (!errors) return;
        if (errors.account) setFieldError("account", errors.account);
        if (errors.password) setFieldError("password", errors.password);
    }

    if (form) {
        form.addEventListener("submit", function (event) {
            event.preventDefault();
            if (submitBtn && submitBtn.classList.contains("is-loading")) return;
            var payload = validateForm();
            if (!payload) return;
            if (!window.AuthAPI || !window.HttpRequest) {
                return;
            }

            setSubmitting(true);

            AuthAPI.login(payload)
                .then(function () {
                    AuthAPI.toast("登录成功", "success");
                    closeDialog();
                    setTimeout(function () {
                        goAfterAuth();
                    }, 400);
                })
                .catch(function (err) {
                    setSubmitting(false);
                    mapServerError(err);
                });
        });
    }

    function isSafeRedirect(path) {
        return typeof path === "string" && path.charAt(0) === "/" && path.charAt(1) !== "/";
    }

    function goAfterAuth() {
        var bodyRedirect = document.body && document.body.getAttribute("data-auth-redirect");
        if (isSafeRedirect(bodyRedirect)) {
            window.location.href = bodyRedirect;
            return;
        }
        var params = new URLSearchParams(window.location.search);
        var redirect = params.get("redirect");
        if (isSafeRedirect(redirect)) {
            window.location.href = redirect;
            return;
        }
        window.location.reload();
    }

    function consumeAuthQuery(kind) {
        var params = new URLSearchParams(window.location.search);
        if (params.get("auth") !== kind) return false;
        params.delete("auth");
        var qs = params.toString();
        var next = window.location.pathname + (qs ? "?" + qs : "") + window.location.hash;
        window.history.replaceState(null, "", next);
        return true;
    }

    if (accountInput) {
        accountInput.addEventListener("input", function () {
            clearFieldError("account");
        });
    }

    if (passwordInput) {
        passwordInput.addEventListener("input", function () {
            clearFieldError("password");
        });
    }

    document.addEventListener("click", function (event) {
        var openEl = event.target.closest("[data-login-dialog-open]");
        if (openEl) {
            openDialog(event);
            return;
        }

        var loginLink = event.target.closest('a[href="/login/"], a[href="#login"]');
        if (loginLink) {
            openDialog(event);
            return;
        }

        if (event.target.closest("[data-login-dialog-close]")) {
            closeDialog();
            return;
        }

        if (event.target.closest("[data-login-dialog-eye]")) {
            var btn = event.target.closest("[data-login-dialog-eye]");
            var input = document.getElementById("loginDialogPassword");
            var img = btn.querySelector("img");
            if (!input || !img) return;
            var show = input.type === "password";
            input.type = show ? "text" : "password";
            img.src = show ? "/static/images/eye_open.svg" : "/static/images/eye_close.svg";
            btn.setAttribute("aria-label", show ? "隐藏密码" : "显示密码");
            return;
        }

        if (event.target === mask) {
            closeDialog();
        }
    });

    document.addEventListener("keydown", function (event) {
        if (event.key === "Escape" && mask.classList.contains("is-open")) {
            closeDialog();
        }
    });

    window.openLoginDialog = openDialog;
    window.closeLoginDialog = closeDialog;
    window.setLoginDialogErrors = setLoginErrors;

    if ((document.body && document.body.getAttribute("data-auth-mode") === "login") || consumeAuthQuery("login")) {
        openDialog();
    }
})();