import AppConfig from "@scripts/app/AppConfig";
import { Camera, Canvas, Node, screen, UITransform, Vec3 } from "cc";
import { GoogleImpl, IGoogleBtnLogin, IGoogleLoginRes } from "./GoogleImpl";

interface GoogleCredentialResponse {
    credential?: string;
    select_by?: string;
}

interface GoogleIdentityService {
    initialize: (config: {
        client_id: string;
        callback: (response: GoogleCredentialResponse) => void;
        ux_mode?: "popup" | "redirect";
    }) => void;
    renderButton: (parent: HTMLElement, options: {
        type?: "standard" | "icon";
        theme?: "outline" | "filled_blue" | "filled_black";
        size?: "large" | "medium" | "small";
        text?: "signin_with" | "signup_with" | "continue_with" | "signin";
        shape?: "rectangular" | "pill" | "circle" | "square";
        logo_alignment?: "left" | "center";
        width?: number;
    }) => void;
    disableAutoSelect: () => void;
}

interface GoogleSdkWindow extends Window {
    google?: {
        accounts?: {
            id?: GoogleIdentityService;
        };
    };
}

const GOOGLE_SDK_ID = "google-identity-services";
const GOOGLE_SDK_URL = "https://accounts.google.com/gsi/client";

export class GoogleH5Impl extends GoogleImpl {
    private _initPromise: Promise<void> | null = null;
    private _loginCallback: (res: IGoogleLoginRes) => void;
    private _buttonSeed = 0;

    init(): Promise<void> {
        if (this.isInitialized) return Promise.resolve();
        if (this._initPromise) return this._initPromise;

        this._initPromise = this.loadGoogleSdk()
            .then(() => {
                const googleIdentity = this.getGoogleIdentity();
                if (!googleIdentity) {
                    throw new Error("Google Identity Services 初始化失败");
                }

                googleIdentity.initialize({
                    client_id: AppConfig.GoogleID,
                    ux_mode: "popup",
                    callback: response => this.handleCredentialResponse(response),
                });
                this.onInited();

                console.log(googleIdentity);
            })
            .catch(error => {
                this._initPromise = null;
                throw error;
            });

        return this._initPromise;
    }

    protected async onLogin(): Promise<IGoogleLoginRes> {
        return null;
    }

    async logOut(): Promise<boolean> {
        return true;
    }

    createLoginBtn(node: Node, callback: (res: IGoogleLoginRes) => void): IGoogleBtnLogin {
        const container = document.createElement("div");
        container.id = `google-login-button-${++this._buttonSeed}`;
        container.style.position = "fixed";
        container.style.zIndex = "9999";
        container.style.display = "flex";
        container.style.alignItems = "center";
        container.style.justifyContent = "center";
        container.style.overflow = "hidden";
        container.style.boxSizing = "border-box";
        container.style.opacity = "0";
        document.body.appendChild(container);

        let active = node.activeInHierarchy;
        let cleared = false;
        let animationFrameId = 0;

        this._loginCallback = callback;

        const clear = () => {
            if (cleared) return;
            cleared = true;
            window.cancelAnimationFrame(animationFrameId);
            container.remove();
        };

        const update = () => {
            if (cleared) return;
            if (!node.isValid) {
                clear();
                return;
            }

            this.syncDomLayout(container, node, active);
            animationFrameId = window.requestAnimationFrame(update);
        };

        this.syncDomLayout(container, node, active);
        animationFrameId = window.requestAnimationFrame(update);

        this.init()
            .then(() => {
                if (cleared || !node.isValid) return;

                this.syncDomLayout(container, node, active);
                const containerWidth = Math.round(container.getBoundingClientRect().width) || 280;
                const width = Math.max(40, Math.min(400, containerWidth));
                this.getGoogleIdentity()?.renderButton(container, {
                    type: "standard",
                    theme: "outline",
                    size: "large",
                    text: "signin_with",
                    shape: "rectangular",
                    logo_alignment: "left",
                    width,
                });
            })
            .catch(error => {
                console.error("[Google] 登录按钮创建失败", error);
                clear();
            });
        return {
            active,
            setActive: (visible: boolean) => {
                if (cleared) return;
                if (!node.isValid) {
                    clear();
                    return;
                }
                active = visible;
                this.syncDomLayout(container, node, active);
            },
            clear,
        };
    }

    private handleCredentialResponse(response: GoogleCredentialResponse): void {
        console.log('[Google] handleCredentialResponse:', response, !!this._loginCallback)
        const credential = response?.credential || "";
        const result: IGoogleLoginRes = {
            // GIS 返回的是 JWT ID Token，沿用项目接口的 accessToken 字段传递。
            accessToken: credential,
            isCancel: !credential,
            status: credential ? "connected" : "failed",
            reason: credential ? undefined : "Google 登录未返回 credential",
        };

        this._loginCallback?.(result);
    }

    private getGoogleIdentity(): GoogleIdentityService | undefined {
        return (window as GoogleSdkWindow).google?.accounts?.id;
    }

    private loadGoogleSdk(): Promise<void> {
        if (this.getGoogleIdentity()) return Promise.resolve();

        return new Promise((resolve, reject) => {
            let script = document.getElementById(GOOGLE_SDK_ID) as HTMLScriptElement | null;
            if (!script) {
                script = document.createElement("script");
                script.id = GOOGLE_SDK_ID;
                script.src = GOOGLE_SDK_URL;
                script.async = true;
                script.defer = true;
                document.head.appendChild(script);
            }

            const clearListeners = () => {
                window.clearTimeout(timeoutId);
                script?.removeEventListener("load", onLoad);
                script?.removeEventListener("error", onError);
            };
            const onLoad = () => {
                clearListeners();
                this.getGoogleIdentity()
                    ? resolve()
                    : reject(new Error("Google Identity Services SDK 不可用"));
            };
            const onError = () => {
                clearListeners();
                script?.remove();
                reject(new Error("Google Identity Services SDK 下载失败"));
            };
            const timeoutId = window.setTimeout(() => {
                clearListeners();
                script?.remove();
                reject(new Error("Google Identity Services SDK 加载超时"));
            }, 15000);

            script.addEventListener("load", onLoad, { once: true });
            script.addEventListener("error", onError, { once: true });
        });
    }

    private syncDomLayout(container: HTMLDivElement, node: Node, active: boolean): void {
        if (!active || !node.activeInHierarchy) {
            container.style.display = "none";
            return;
        }

        const uiTransform = node.getComponent(UITransform);
        const camera = this.findCanvasCamera(node);
        const gameCanvas = this.getGameCanvas();
        if (!uiTransform || !camera || !gameCanvas) {
            container.style.display = "none";
            return;
        }

        const worldBounds = uiTransform.getBoundingBoxToWorld();
        const worldZ = node.worldPosition.z;
        const bottomLeft = camera.worldToScreen(new Vec3(worldBounds.xMin, worldBounds.yMin, worldZ));
        const topRight = camera.worldToScreen(new Vec3(worldBounds.xMax, worldBounds.yMax, worldZ));
        const screenWidth = screen.windowSize.width || gameCanvas.width;
        const screenHeight = screen.windowSize.height || gameCanvas.height;
        if (screenWidth <= 0 || screenHeight <= 0) {
            container.style.display = "none";
            return;
        }

        const canvasRect = gameCanvas.getBoundingClientRect();
        const minX = Math.min(bottomLeft.x, topRight.x);
        const maxX = Math.max(bottomLeft.x, topRight.x);
        const minY = Math.min(bottomLeft.y, topRight.y);
        const maxY = Math.max(bottomLeft.y, topRight.y);

        container.style.display = "flex";
        container.style.left = `${canvasRect.left + minX / screenWidth * canvasRect.width}px`;
        container.style.top = `${canvasRect.top + (1 - maxY / screenHeight) * canvasRect.height}px`;
        container.style.width = `${(maxX - minX) / screenWidth * canvasRect.width}px`;
        container.style.height = `${(maxY - minY) / screenHeight * canvasRect.height}px`;
    }

    private findCanvasCamera(node: Node): Camera | null {
        let current: Node | null = node;
        while (current) {
            const canvas = current.getComponent(Canvas);
            if (canvas) return canvas.cameraComponent || current.getComponent(Camera);
            current = current.parent;
        }
        return null;
    }

    private getGameCanvas(): HTMLCanvasElement | null {
        const gameCanvas = document.getElementById("GameCanvas");
        if (gameCanvas instanceof HTMLCanvasElement) return gameCanvas;
        return document.querySelector("canvas");
    }
}