// 忘记密码页面交互逻辑：智能账号检测与分流引导

let passwordForgotControlsBound = false;
let currentUsername = "";

/**
 * 读取 CSRF 令牌，供找回密码请求使用。
 *
 * @returns {string}
 */
function getCsrfToken() {
    return document.querySelector('meta[name="csrf-token"]')?.getAttribute("content") ?? "";
}

/**
 * 获取当前应当使用的局部消息框元素。
 *
 * @returns {HTMLDivElement|null}
 */
function getActiveAlertBox() {
    const stepDetect = document.getElementById("step-detect");
    if (stepDetect && stepDetect.style.display !== "none") {
        return document.getElementById("alert-detect");
    }
    return document.getElementById("alert-email");
}

/**
 * 展示找回密码页面提示。
 *
 * @param {string} message
 * @param {string} type
 * @returns {void}
 */
function showAlert(message, type) {
    const alertBox = getActiveAlertBox();
    if (!alertBox) {
        return;
    }

    alertBox.textContent = message;
    alertBox.className = type === "success" ? "alert alert-success" : "alert alert-error";
    alertBox.style.display = "block";
    
    // 平滑滚动提示框到可视区域
    alertBox.scrollIntoView({ behavior: "smooth", block: "nearest" });
}

/**
 * 隐藏找回密码页面提示。
 *
 * @returns {void}
 */
function hideAlert() {
    const alertDetect = document.getElementById("alert-detect");
    const alertEmail = document.getElementById("alert-email");
    if (alertDetect) {
        alertDetect.style.display = "none";
    }
    if (alertEmail) {
        alertEmail.style.display = "none";
    }
}

/**
 * 绑定双绑定状态下的选项卡切换事件。
 *
 * @returns {void}
 */
function bindTabEvents() {
    const tabsContainer = document.getElementById("channel-tabs");
    if (!tabsContainer) {
        return;
    }

    tabsContainer.addEventListener("click", (event) => {
        const btn = event.target.closest(".tab-btn");
        if (!btn) {
            return;
        }

        // 清除所有高亮
        tabsContainer.querySelectorAll(".tab-btn").forEach((b) => b.classList.remove("active"));
        btn.classList.add("active");

        // 切换显示面板
        const targetId = btn.getAttribute("data-target");
        document.querySelectorAll(".channel-pane").forEach((pane) => {
            if (pane.id === targetId) {
                pane.style.display = "block";
            } else {
                pane.style.display = "none";
            }
        });
    });
}

/**
 * 第一步：提交昵称检测账号绑定状态。
 *
 * @param {SubmitEvent} event
 * @returns {Promise<void>}
 */
async function submitAccountDetect(event) {
    event.preventDefault();
    const form = event.target;
    const detectBtn = document.getElementById("detect-btn");
    if (!(form instanceof HTMLFormElement)) {
        return;
    }

    if (detectBtn instanceof HTMLButtonElement) {
        detectBtn.disabled = true;
        detectBtn.innerText = "账号检索中...";
    }
    hideAlert();

    try {
        const response = await fetch(form.action, {
            method: "POST",
            headers: {
                "Content-Type": "application/json",
                "X-CSRF-TOKEN": getCsrfToken(),
                Accept: "application/json",
            },
            body: JSON.stringify(Object.fromEntries(new FormData(form).entries())),
        });
        const body = await response.json();

        if (response.status === 429) {
            showAlert(body.message || "请求过于频繁，请稍后再试。", "error");
            return;
        }

        if (body.status === "not_found") {
            showAlert(body.message, "error");
            return;
        }

        if (body.status === "success") {
            currentUsername = body.username;
            document.getElementById("step-detect").style.display = "none";
            document.getElementById("step-result").style.display = "block";
            document.getElementById("recovery-title").innerText = "密码找回建议";
            document.getElementById("forgot-footer").style.display = "none";

            const summary = document.getElementById("detect-summary");
            const tabs = document.getElementById("channel-tabs");
            const panelWechat = document.getElementById("panel-wechat");
            const panelEmail = document.getElementById("panel-email");
            const panelNone = document.getElementById("panel-none");

            // 默认隐藏所有特定面板
            tabs.style.display = "none";
            panelWechat.style.display = "none";
            panelEmail.style.display = "none";
            panelNone.style.display = "none";

            const hasEmail = body.has_email;
            const hasWechat = body.has_wechat;

            const hintLabel = document.getElementById("masked-email-hint");
            const emailInput = document.getElementById("email");

            if (hasEmail && hasWechat) {
                summary.innerHTML = `检测到账号 <strong style="color:var(--gold);">${currentUsername}</strong> 已同时绑定了微信和邮箱。您可以选择以下任意一种方式找回密码：`;
                tabs.style.display = "grid";
                // 默认选中微信面板
                tabs.querySelectorAll(".tab-btn").forEach((b) => b.classList.remove("active"));
                const wechatTabBtn = tabs.querySelector('[data-target="panel-wechat"]');
                if (wechatTabBtn) {
                    wechatTabBtn.classList.add("active");
                }
                panelWechat.style.display = "block";
                
                if (hintLabel) {
                    hintLabel.innerHTML = `📬 绑定的邮箱提示：<span style="color:#fff;">${body.masked_email}</span>`;
                }
                if (emailInput instanceof HTMLInputElement) {
                    emailInput.value = "";
                }
            } else if (hasWechat) {
                summary.innerHTML = `检测到账号 <strong style="color:var(--gold);">${currentUsername}</strong> 仅绑定了微信。系统不支持邮箱找回，建议您使用微信助手进行重置：`;
                panelWechat.style.display = "block";
            } else if (hasEmail) {
                summary.innerHTML = `检测到账号 <strong style="color:var(--gold);">${currentUsername}</strong> 仅绑定了邮箱。建议您使用邮箱发送重置链接找回：`;
                panelEmail.style.display = "block";
                if (hintLabel) {
                    hintLabel.innerHTML = `📬 绑定的邮箱提示：<span style="color:#fff;">${body.masked_email}</span>`;
                }
                if (emailInput instanceof HTMLInputElement) {
                    emailInput.value = "";
                }
            } else {
                summary.innerHTML = `检测到账号 <strong style="color:var(--gold);">${currentUsername}</strong> 尚未绑定微信或邮箱找回途径：`;
                panelNone.style.display = "block";
            }
        }
    } catch {
        showAlert("网络或服务器连接异常，请稍后再试。", "error");
    } finally {
        if (detectBtn instanceof HTMLButtonElement) {
            detectBtn.disabled = false;
            detectBtn.innerText = "下一步 (检测账号)";
        }
    }
}

/**
 * 第二步：提交发送重置链接邮件请求。
 *
 * @param {SubmitEvent} event
 * @returns {Promise<void>}
 */
async function submitPasswordRecovery(event) {
    event.preventDefault();
    const form = event.target;
    const submitButton = document.getElementById("submit-btn");
    if (!(form instanceof HTMLFormElement)) {
        return;
    }

    if (submitButton instanceof HTMLButtonElement) {
        submitButton.disabled = true;
        submitButton.innerText = "发送重置链接中...";
    }
    hideAlert();

    let isSentSuccess = false;

    try {
        const emailInput = document.getElementById("email");
        const emailVal = emailInput instanceof HTMLInputElement ? emailInput.value.trim() : "";

        const response = await fetch(form.getAttribute("data-password-email-url") ?? "", {
            method: "POST",
            headers: {
                "Content-Type": "application/json",
                "X-CSRF-TOKEN": getCsrfToken(),
                Accept: "application/json",
            },
            body: JSON.stringify({
                username: currentUsername,
                email: emailVal,
            }),
        });
        const body = await response.json();

        if (response.status === 429) {
            showAlert(body.message || "请求发送过于频繁，请稍后再试。", "error");
            return;
        }

        if (body.status === "success") {
            showAlert(body.message, "success");
            isSentSuccess = true;
            return;
        }

        const errorMessage = body.message || (body.errors ? Object.values(body.errors)[0][0] : "重置邮件发送失败，请稍后重试。");
        showAlert(errorMessage, "error");
    } catch {
        showAlert("网络发送异常，请稍后再试。", "error");
    } finally {
        if (submitButton instanceof HTMLButtonElement) {
            if (isSentSuccess) {
                // 成功时启动 30 秒置灰倒计时锁定
                let seconds = 30;
                submitButton.disabled = true;
                submitButton.innerText = `${seconds}秒内不能重复发送`;

                const timer = setInterval(() => {
                    seconds--;
                    if (seconds <= 0) {
                        clearInterval(timer);
                        submitButton.disabled = false;
                        submitButton.innerText = "二次验证并发送重置邮件";
                    } else {
                        submitButton.innerText = `${seconds}秒内不能重复发送`;
                    }
                }, 1000);
            } else {
                // 校验失败，立刻解除禁用供重新编辑
                submitButton.disabled = false;
                submitButton.innerText = "二次验证并发送重置邮件";
            }
        }
    }
}

/**
 * 绑定智能找回向导控制事件。
 *
 * @returns {void}
 */
function bindPasswordForgotControls() {
    if (passwordForgotControlsBound || typeof document === "undefined") {
        return;
    }
    passwordForgotControlsBound = true;

    // 第一步表单提交
    document.getElementById("account-detect-form")?.addEventListener("submit", (event) => {
        void submitAccountDetect(event);
    });

    // 第二步发信表单提交
    document.getElementById("password-recovery-form")?.addEventListener("submit", (event) => {
        void submitPasswordRecovery(event);
    });

    // 返回按钮事件
    document.getElementById("back-detect-btn")?.addEventListener("click", () => {
        hideAlert();
        document.getElementById("step-detect").style.display = "block";
        document.getElementById("step-result").style.display = "none";
        document.getElementById("recovery-title").innerText = "忘记密码";
        document.getElementById("forgot-footer").style.display = "block";
    });

    bindTabEvents();
}

bindPasswordForgotControls();