const RESTART_STATUS_URL = "/o1key/restart/status";
const RESTART_TIMEOUT_MS = 120_000;
let restartInProgress = false;

async function readJson(response) {
    const data = await response.json().catch(() => ({}));
    if (!response.ok) throw new Error(data.error || `请求失败 (${response.status})`);
    return data;
}

function delay(milliseconds) {
    return new Promise((resolve) => window.setTimeout(resolve, milliseconds));
}

async function fetchWithTimeout(url, options = {}, timeout = 2_500) {
    const controller = new AbortController();
    const timer = window.setTimeout(() => controller.abort(), timeout);
    try {
        return await fetch(url, {
            ...options,
            cache: "no-store",
            signal: controller.signal,
        });
    } finally {
        window.clearTimeout(timer);
    }
}

async function getRestartStatus() {
    const separator = RESTART_STATUS_URL.includes("?") ? "&" : "?";
    const response = await fetchWithTimeout(
        `${RESTART_STATUS_URL}${separator}_=${Date.now()}`
    );
    return readJson(response);
}

function setRestartButtonState(button, busy) {
    if (!button) return;
    button.disabled = busy;
    button.setAttribute("aria-busy", String(busy));
    button.setAttribute("aria-label", busy ? "ComfyUI 正在重启" : "重启");
    button.setAttribute("title", busy ? "ComfyUI 正在重启" : "重启");

    const icon = button.querySelector(".side-bar-button-icon");
    if (icon) {
        icon.className = busy
            ? "pi pi-spinner pi-spin side-bar-button-icon"
            : "pi pi-refresh side-bar-button-icon";
    }

    const label = button.querySelector(".side-bar-button-label");
    if (label) label.textContent = busy ? "重启中" : "重启";
}

async function waitForRestart(oldBootId) {
    const deadline = Date.now() + RESTART_TIMEOUT_MS;

    while (Date.now() < deadline) {
        try {
            const status = await getRestartStatus();
            if (status.ready && status.boot_id && status.boot_id !== oldBootId) {
                const systemStatus = await fetchWithTimeout(
                    `/api/system_stats?_=${Date.now()}`
                );
                if (systemStatus.ok) return;
            }
        } catch {
            // 旧进程退出到新进程监听端口之间，接口暂时不可用是正常状态。
        }
        await delay(1_000);
    }

    throw new Error("等待 ComfyUI 重启超时，请查看终端中的错误信息。");
}

function reloadAfterRestart() {
    const url = new URL(window.location.href);
    url.searchParams.set("o1key_restart", Date.now().toString());
    window.location.replace(url.toString());
}

export async function startComfyUIRestart() {
    if (restartInProgress) throw new Error("ComfyUI 正在重启，请稍候。");
    restartInProgress = true;
    let reloadRequested = false;
    const button = document.querySelector("#o1key-restart-button");
    setRestartButtonState(button, true);

    try {
        let currentStatus = null;
        try {
            currentStatus = await getRestartStatus();
        } catch {
            // POST 响应还会返回旧进程的 boot_id，因此预检失败不阻断重启。
        }

        const response = await fetchWithTimeout("/o1key/restart", {
            method: "POST",
            headers: { "Content-Type": "application/json" },
            body: "{}",
        }, 5_000);
        const result = await readJson(response);
        const oldBootId = result.boot_id || currentStatus?.boot_id;
        if (!oldBootId) throw new Error("无法确认当前 ComfyUI 进程标识。");

        await waitForRestart(oldBootId);
        reloadAfterRestart();
        reloadRequested = true;
    } catch (error) {
        setRestartButtonState(button, false);
        throw error;
    } finally {
        if (!reloadRequested) restartInProgress = false;
    }
}