import { createAlova, Method, StatesHook } from "alova";
import fetchAdapter from "alova/fetch";
import VueHook from "alova/vue";
import { replaceOriginUrl } from "../bschSsoRedirect";
import config from "@/assets/config/host.config";
import Utils from "..";
/* ============= 类型定义 ============= */
export interface RequestHooks {
    /** 前置票据/通用头注入 */
    injectHeaders?: (method: Method) => void;
    /** 加载开始 */
    onLoadingStart?: () => void;
    /** 加载结束 */
    onLoadingEnd?: () => void;
    /** 业务错误提示（code !== 0）*/
    onBizError?: (msg: string) => void;
    /** http 错误提示（status !== 200）*/
    onHttpError?: (msg: string) => void;
}

/** 和后端约定的通用响应格式 */
export interface BschResponse<T = any> {
    code: number;
    msg?: string;
    data: T;
    urlToRedirectTo?: string;
}

/* ============= 默认空实现 ============= */
const defHooks: Required<RequestHooks> = {
    injectHeaders: () => {},
    onLoadingStart: () => {},
    onLoadingEnd: () => {},
    onBizError: () => {},
    onHttpError: () => {},
};

/* ============= 错误处理（原 axios 逻辑平移） ============= */
function errorHandle<T>(res: BschResponse<T>, status: number): T {
    // http 层错误
    if (status !== 200) {
        let msg = "网络错误";
        switch (status) {
            case 401:
            case 403:
                break;
            case 404:
                msg = "请求的资源不存在!";
                break;
            default:
                msg = res?.msg || "内部服务错误！";
        }
        throw new Error(msg);
    }

    // 业务层错误
    switch (res.code) {
        case 0:
            return res.data ?? (null as T);
        case 302:
            console.log(res);
            window.location.href = res.urlToRedirectTo!;
            // window.location.href = replaceOriginUrl(res.urlToRedirectTo!, config.serviceHost);
            throw new Error("redirect");
        case 4:
            throw new Error(res.msg || "参数错误!");
        default:
            throw new Error(res.msg || "业务错误");
    }
}

/* ============= 工厂函数 ============= */
export function createBschAlova(baseURL: string, hooks: RequestHooks = {}, statesHook: StatesHook<any> = VueHook) {
    const { injectHeaders, onLoadingStart, onLoadingEnd, onBizError, onHttpError } = {
        ...defHooks,
        ...hooks,
    };

    let reqCount = 0;
    let timer: ReturnType<typeof setTimeout>;

    /* ---- 请求拦截 ---- */
    function beforeRequest(method: Method) {
        reqCount++;
        if (reqCount === 1) timer = setTimeout(() => onLoadingStart(), 800);

        Promise.resolve().then(() => {
            if (reqCount === 0) {
                clearTimeout(timer);
                onLoadingEnd();
            }
        });
        // 1. 用户注入票据/角色等头
        injectHeaders(method);

        method.config.credentials = "include";
        // 2. 通用头
        method.config.headers = Object.assign(method.config.headers || {}, {
            yschapirequest: "1",
            timeout: 20000,
            yschreferer: Utils.strToHexCharCode(window.location.href),
        });
    }

    /* ---- 响应拦截 ---- */
    async function onSuccess(response: Response) {
        reqCount--;
        if (reqCount === 0) {
            clearTimeout(timer);
            onLoadingEnd();
        }
        const res: BschResponse = await response.json();
        try {
            return errorHandle(res, response.status);
        } catch (e: any) {
            console.log(e);

            onBizError(e.message);
            return Promise.reject(e);
        }
    }

    async function onError(err: any) {
        reqCount = 0;
        clearTimeout(timer);
        onLoadingEnd();

        const msg = err?.message || "网络请求出错";
        onHttpError(msg);
        return Promise.reject(err);
    }

    async function onComplete(method: Method) {
        if (method.fromCache) {
            reqCount--;
            if (reqCount === 0) {
                clearTimeout(timer);
                onLoadingEnd();
            }
        }
    }

    return createAlova({
        statesHook,
        requestAdapter: fetchAdapter(),
        baseURL,
        cacheFor: null,
        beforeRequest,
        responded: { onSuccess, onError, onComplete },
    });
}