import { R } from "utils/helper.js"
import Router from "utils/router.js"

class AuthController {
    constructor() {}

    /**
     * 通用请求函数：依次请求网址数组，返回第一个成功的响应及其类型
     * @param {string[]} urls
     * @returns {Promise<{type: string, data: any}>}
     */
    async fetchFirstSuccess(urls) {
        for (const url of urls) {
            try {
                const res = await fetch(url, { method: "get", mode: "cors", redirect: "follow" })
                if (!res.ok) continue
                const contentType = res.headers.get("content-type") || ""
                let data, type
                if (contentType.includes("application/json")) {
                    data = await res.json()
                    type = "json"
                } else if (contentType.includes("text/")) {
                    data = await res.text()
                    type = "text"
                } else {
                    data = await res.blob()
                    type = "blob"
                }
                return { type, data }
            } catch (e) {
                // ignore and try next url
            }
        }
        throw new Error("All requests failed")
    }

    async random(ctx) {
        const { type, data } = await this.fetchFirstSuccess(["https://api.miaomc.cn/image/get"])
        if (type === "blob") {
            ctx.set("Content-Type", "image/jpeg")
            ctx.body = data
        } else {
            R.response(R.ERROR, "Failed to fetch image")
        }
    }

    /**
     * 路由注册
     */
    static createRoutes() {
        const controller = new AuthController()
        const router = new Router({ prefix: "/api/pics" })
        router.get("/random", controller.random.bind(controller), { auth: false })
        return router
    }
}

export default AuthController