import { lib, game, ui } from "../../../../noname.js";
import { save } from "../../../../noname/util/config.js";

let selectingMode = false;

// Reuse the registered engine splash, not reload-to-the-current-mode or a fake mode list.
export const openModeSelection = async () => {
    if (selectingMode) return;
    const splash = lib.onloadSplashes.find(item => item.id === lib.config.splash_style) || lib.onloadSplashes[0];
    if (!splash) throw new Error("模式选择界面未加载，请稍后重试。");
    selectingMode = true;
    const previousSplash = window.inSplash;
    const previousFocus = document.activeElement;
    const previousInert = ui.window.inert;
    const node = ui.create.div("#splash", document.body);
    node.style.zIndex = "1000";
    window.inSplash = true;
    ui.window.inert = true;
    try {
        let choose;
        const selected = new Promise(resolve => { choose = resolve; });
        await splash.init(node, choose);
        const mode = await selected;
        if (!lib.config.all.mode.includes(mode)) throw new Error("所选模式不可用。");
        await save("mode", "config", mode);
        lib.config.mode = mode;
        localStorage.setItem(`${lib.configprefix}directstart`, "true");
        // Reload only AFTER a mode is chosen; retain engine pending-write handling.
        node.inert = true;
        game.reload();
        // Keep the abandoned flow inert while the engine waits for pending DB writes.
        await new Promise(() => {});
    } catch (error) {
        // DefaultSplash owns a Vue app. Clean it up if opening/saving failed.
        splash.app?.unmount?.();
        throw error;
    } finally {
        node.remove();
        window.inSplash = previousSplash;
        ui.window.inert = previousInert;
        selectingMode = false;
        if (previousFocus?.isConnected) previousFocus.focus();
    }
};

export const askMenu = (title, description, choices) => new Promise(resolve => {
    const previousFocus = document.activeElement;
    const dialog = document.createElement("dialog");
    dialog.className = "mengsan-menu-dialog-shuying";
    dialog.setAttribute("aria-label", title);
    const heading = document.createElement("h2");
    heading.textContent = title;
    const body = document.createElement("p");
    body.textContent = description;
    dialog.append(heading, body);
    let closed = false;
    const finish = value => {
        if (closed) return;
        closed = true;
        dialog.close();
        dialog.remove();
        if (previousFocus?.isConnected) previousFocus.focus();
        resolve(value);
    };
    for (const choice of choices) {
        const button = document.createElement("button");
        button.type = "button";
        button.textContent = choice.name;
        if (choice.danger) button.className = "danger";
        button.addEventListener("click", () => finish(choice.id));
        dialog.appendChild(button);
    }
    dialog.addEventListener("cancel", event => { event.preventDefault(); finish(null); });
    document.body.appendChild(dialog);
    dialog.showModal();
    dialog.querySelector("button")?.focus();
});

export const mountMenu = (overlay, options = {}) => {
    const button = document.createElement("button");
    button.type = "button";
    button.className = "mengsan-flow-menu-shuying";
    const icon = document.createElementNS("http://www.w3.org/2000/svg", "svg");
    icon.setAttribute("viewBox", "0 0 24 24");
    icon.setAttribute("aria-hidden", "true");
    const path = document.createElementNS("http://www.w3.org/2000/svg", "path");
    path.setAttribute("d", "M4 6h16M4 12h16M4 18h16");
    icon.appendChild(path);
    const label = document.createElement("span");
    label.textContent = "菜单";
    button.append(icon, label);
    button.setAttribute("aria-haspopup", "dialog");
    let opened = false;
    button.addEventListener("click", async event => {
        event.stopPropagation();
        if (opened) return;
        opened = true;
        options.onOpen?.();
        try {
            const action = await askMenu("征程菜单", "退出不删除存档。未完成的节点与对话将在下次进入时重新开始。", [
                { id: "resume", name: "继续当前界面" },
                { id: "exit", name: "返回模式选择" },
            ]);
            if (action !== "exit") return;
            const confirmed = await askMenu("返回模式选择？", "保留上次已完成节点的存档。本次尚未完成的内容不会提交。", [
                { id: "cancel", name: "留在梦三" },
                { id: "confirm", name: "确认返回模式选择", danger: true },
            ]);
            if (confirmed === "confirm") await openModeSelection();
        } catch (error) {
            console.error("梦三返回模式选择失败：", error);
            await askMenu("暂时无法返回", "没有清除征程。请关闭提示后重试。", [{ id: "close", name: "回到当前界面" }]);
        } finally {
            opened = false;
            options.onClose?.();
        }
    });
    overlay.appendChild(button);
    return button;
};