import type {Dispatcher} from "undici"
import {Pool, request} from "undici"

const apiURL = "https://api.soundcloud.com"
const apiV2URL = "https://api-v2.soundcloud.com"
const webURL = "https://soundcloud.com"

export class API {
    public static headers: Record<string, any> = {
        Origin: "https://soundcloud.com",
        Referer: "https://soundcloud.com/",
        "User-Agent": "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36 Edg/114.0.1823.67",
    }
    public api = new Pool(apiURL)
    public apiV2 = new Pool(apiV2URL)
    public web = new Pool(webURL)
    public proxy?: Pool
    constructor(public clientId?: string, public oauthToken?: string, proxy?: string) {
        if (oauthToken) API.headers.Authorization = `OAuth ${oauthToken}`
        if (proxy) this.proxy = new Pool(proxy)
    }

    get headers() {
        return API.headers
    }

    /**
     * Gets an endpoint from the Soundcloud API.
     */
    public get = (endpoint: string, params?: Record<string, any>) => {
        return this.getRequest(this.api, apiURL, endpoint, params)
    }

    /**
     * Gets an endpoint from the Soundcloud V2 API.
     */
    public getV2 = (endpoint: string, params?: Record<string, any>) => {
        return this.getRequest(this.apiV2, apiV2URL, endpoint, params)
    }

    /**
     * Some endpoints use the main website as the URL.
     */
    public getWebsite = (endpoint: string, params?: Record<string, any>) => {
        return this.getRequest(this.web, webURL, endpoint, params)
    }

    /**
     * Gets a URL, such as download, stream, attachment, etc.
     */
    public getURL = (URI: string, params?: Record<string, any>) => {
        if (this.proxy) return this.request(this.proxy, this.buildOptions(URI, "GET", params))
        const options = {
            query: params || {},
            headers: API.headers,
            maxRedirections: 5,
        }
        if (this.clientId) options.query.client_id = this.clientId
        if (this.oauthToken) options.query.oauth_token = this.oauthToken
        return request(URI, options).then(r => {
            if (r.statusCode.toString().startsWith("2")) {
                if (r.headers["content-type"] === "application/json") return r.body.json()
                return r.body.text()
            }
            throw new Error(`Status code ${r.statusCode}`)
        })
    }

    private readonly buildOptions = (path: string, method: Dispatcher.HttpMethod = "GET", params?: Record<string, any>) => {
        const options: Dispatcher.RequestOptions = {
            query: (method == "GET" && params) || {},
            headers: API.headers,
            method,
            path,
            maxRedirections: 5,
        }
        if (method === "POST" && params) options.body = JSON.stringify(params)
        if (this.clientId) options.query.client_id = this.clientId
        if (this.oauthToken) options.query.oauth_token = this.oauthToken
        return options
    }

    private readonly request = (pool: Pool, options: Dispatcher.RequestOptions) => {
        return pool.request(options).then(r => {
            if (r.statusCode.toString().startsWith("2")) {
                if (r.headers["content-type"].includes("application/json")) return r.body.json()
                return r.body.text()
            }
            throw new Error(`Status code ${r.statusCode}`)
        })
    }

    private readonly getRequest = async (pool: Pool, origin: string, endpoint: string, params?: Record<string, any>) => {
        if (!this.clientId) await this.getClientId()
        if (endpoint.startsWith("/")) endpoint = endpoint.slice(1)
        const options = this.buildOptions(`${this.proxy ? origin : ""}/${endpoint}`, "GET", params)
        try {
            return await this.request(this.proxy || pool, options)
        } catch {
            await this.getClientId(true)
            return this.request(this.proxy || pool, options)
        }
    }

    public post = async (endpoint: string, params?: Record<string, any>) => {
        if (!this.clientId) await this.getClientId()
        if (endpoint.startsWith("/")) endpoint = endpoint.slice(1)
        const options = this.buildOptions(`${this.proxy ? origin : ""}/${endpoint}`, "POST", params)
        return this.request(this.proxy || this.api, options)
    }

    public getClientIdWeb = async () => {
        const response = await this.request(this.proxy || this.web, this.buildOptions(this.proxy ? webURL : "/"))
        if (!response || typeof response !== "string") throw new Error("Could not find client ID")
        const urls = response.match(/(?!<script.*?src=")https?:\/\/(www\.)?[-a-zA-Z0-9@:%._+~#=]{1,256}\.[a-zA-Z0-9()]{1,6}\b([-a-zA-Z0-9()@:%_+.~#?&//=]*\.js)(?=.*?>)/g)
        if (!urls || urls.length === 0) throw new Error("Could not find script URLs")
        do {
            const script = await (this.proxy
                ? this.request(this.proxy, this.buildOptions(urls.pop()))
                : request(urls.pop()).then(r => r.body.text()))
            if (!script || typeof script !== "string") continue
            const clientId = script.match(/[{,]client_id:"(\w+)"/)?.[1]
            if (typeof clientId === "string") return clientId
        } while (urls.length > 0)
        throw new Error("Could not find client ID in script URLs")
    }

    public getClientIdMobile = async () => {
        const response = await request("https://m.soundcloud.com/", {
            headers: {
                "User-Agent":
                    "Mozilla/5.0 (iPhone; CPU iPhone OS 16_5_1 like Mac OS X) " +
                    "AppleWebKit/605.1.15 (KHTML, like Gecko) CriOS/99.0.4844.47 Mobile/15E148 Safari/604.1",
            },
        }).then(r => r.body.text())
        const clientId = response.match(/"clientId":"(\w+?)"/)?.[1]
        if (typeof clientId === "string") return clientId
        throw new Error("Could not find client ID")
    }

    public getClientId = async (reset?: boolean) => {
        if (!this.oauthToken && (!this.clientId || reset)) {
            this.clientId = await this.getClientIdWeb().catch(webError =>
                this.getClientIdMobile().catch(mobileError => {
                    throw new Error(
                        "Could not find client ID. Please provide one in the constructor. (Guide: https://github.com/Tenpi/soundcloud.ts#getting-started)" +
                            `\nWeb error: ${webError}` +
                            `\nMobile error: ${mobileError}`
                    )
                })
            )
        }
        return this.clientId
    }
}