import got from "got";
import config from "../../config";
import delay from "../../util/delay";
import PostDatabase from "../../services/postDatabase";

export const dedupeDb = new PostDatabase("e926dedupe.json", 100);

export interface GetPostQuery {
    tags: readonly string[];
    tagsBlacklist: readonly string[];
    maxPage: number;
}

export interface Post {
    id: number;
    file: {
        url: string;
    };
    sources: readonly string[];

    tags: {
        general: readonly string[];
        species: readonly string[];
        character: readonly string[];
        copyright: readonly string[];
        artist: readonly string[];
        invalid: readonly string[];
        lore: readonly string[];
        meta: readonly string[];
    };
}

export const client = got.extend({
    headers: {
        "User-Agent": config.e621.userAgent,
    },
});

export async function getPostById(id: number) {
    const response = await client
        .get("https://e926.net/posts.json", {
            searchParams: {
                tags: `id:${id}`,
            },
        })
        .json<{ posts: readonly Post[] }>();

    if (!response.posts.length) {
        throw new Error("No posts received");
    }

    return response.posts[0];
}

export async function getRandomPost(query: GetPostQuery): Promise<Post> {
    const page = Math.floor(Math.random() * (query.maxPage - 1)) + 1;

    const response = await client
        .get("https://e926.net/posts.json", {
            searchParams: {
                limit: 75,
                page,
                tags: query.tags.join(" "),
            },
        })
        .json<{ posts: readonly Post[] }>();

    if (!response.posts.length) {
        throw new Error("No posts received");
    }

    const postIndex = Math.floor(Math.random() * response.posts.length);
    const post = response.posts[postIndex];
    const mergedTags = [
        ...post.tags.artist,
        ...post.tags.character,
        ...post.tags.copyright,
        ...post.tags.general,
        ...post.tags.invalid,
        ...post.tags.lore,
        ...post.tags.meta,
        ...post.tags.species,
    ];

    if (query.tagsBlacklist.some(tag => mergedTags.includes(tag))) {
        await delay(1000);
        return getRandomPost(query);
    }

    if (config.e621.blacklist.includes(post.id)) {
        await delay(1000);
        return getRandomPost(query);
    }

    const isDupe = await dedupeDb.insertIfNotExists({ provider: "e926", id: post.id });

    if (isDupe) {
        await delay(1000);
        return getRandomPost(query);
    }

    return post;
}