import { Config } from "./config.ts";
import { load_gallery_metadata } from "./page/GalleryMetadata.ts";
import { load_gallery_page } from "./page/GalleryPage.ts";
import { load_single_page } from "./page/SinglePage.ts";

export type GID = [number, string];

export class Client {
    cookies;
    host;
    ua;
    constructor(cfg: Config) {
        this.cookies = cfg.cookies;
        this.ua = cfg.ua ||
            "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/108.0.0.0 Safari/537.36";
        this.host = cfg.ex ? "exhentai.org" : "e-hentai.org";
    }
    get(
        url: string | Request | URL,
        options: RequestInit | undefined = undefined,
    ) {
        return this.request(url, "GET", options);
    }
    post(
        url: string | Request | URL,
        options: RequestInit | undefined = undefined,
    ) {
        return this.request(url, "POST", options);
    }
    request(
        url: string | Request | URL,
        method: string | undefined = undefined,
        options: RequestInit | undefined = undefined,
    ) {
        const headers = new Headers();
        headers.set("User-Agent", this.ua);
        if (this.cookies) {
            if (typeof url === "string") {
                const u = new URL(url);
                if (
                    u.hostname == "e-hentai.org" || u.hostname == "exhentai.org"
                ) {
                    headers.set("Cookie", this.cookies);
                }
            } else if (url instanceof Request) {
                const u = new URL(url.url);
                if (
                    u.hostname == "e-hentai.org" || u.hostname == "exhentai.org"
                ) {
                    headers.set("Cookie", this.cookies);
                }
            } else if (url instanceof URL) {
                if (
                    url.hostname == "e-hentai.org" ||
                    url.hostname == "exhentai.org"
                ) {
                    headers.set("Cookie", this.cookies);
                }
            }
        }
        if (url instanceof Request) {
            for (const v of headers) {
                url.headers.set(v[0], v[1]);
            }
            return fetch(url);
        } else {
            return fetch(
                url,
                Object.assign({ headers, method: method || "GET" }, options),
            );
        }
    }
    /**
     * Fetch a single page (use HTML)
     * @param gid Gallery ID
     * @param page_token Page token
     * @param index Page index
     * @returns
     */
    async fetchSignlePage(gid: number, page_token: string, index: number) {
        const url = `https://${this.host}/s/${page_token}/${gid}-${index}`;
        const re = await this.get(url);
        if (re.status != 200) {
            throw new Error(
                `Fetch ${url} failed, status ${re.status} ${re.statusText}`,
            );
        }
        return load_single_page(await re.text(), this);
    }
    /**
     * Fetch metadata via API
     * @param gids A list of Gallery ID and token
     * @returns 
     */
    async fetchGalleryMetadataByAPI(...gids: GID[]) {
        if (gids.length > 25) throw Error("Load limiting is reached.");
        const data = { method: "gdata", gidlist: gids, namespace: 1 };
        const re = await this.post(`https://${this.host}/api.php`, {
            body: JSON.stringify(data),
            headers: { "content-type": "application/json" },
        });
        if (re.status != 200) {
            throw new Error(
                `Fetch api.php failed, status ${re.status} ${re.statusText}`,
            );
        }
        return load_gallery_metadata(await re.text());
    }
    /**
     * Fetch a gallery page (use HTML)
     * @param gid Gallery ID
     * @param token Token
     * @returns
     */
    async fetchGalleryPage(gid: number, token: string) {
        const url = `https://${this.host}/g/${gid}/${token}/`;
        const re = await this.get(url);
        if (re.status != 200) {
            throw new Error(
                `Fetch ${url} failed, status ${re.status} ${re.statusText}`,
            );
        }
        return load_gallery_page(await re.text(), this);
    }
}