import {throttle} from "throttle-debounce";
import {Post, Topic} from "@/contexts/topics";
import {iso8601ToFrench, frenchToIso8601, getCurrentTimeIso8601} from "./dates"
import {Settings} from "@/contexts/settings";
import {LogAction} from "@/contexts/log";
import {streamAPI as beamStreamAPI} from "@/utils/beam";

const titleRegex = /Sujet\s+:\s+"(.+?)"?<\|eot_id\|>/;
const userRegex = /<\|im_pseudo\|>([^<]+)<\|end_pseudo\|>/;
const dateRegex = /<\|im_date\|>([^<]+)<\|end_date\|>/;
const contentRegex = /<\|begin_of_post\|>([\s\S]+)(?:<\|end_of_post\|>)?$/;

export async function feedTopic(
    settings: Settings,
    log: LogAction,
    topicId: string,
    feed: (topic: Topic) => void
): Promise<void> {
    // console.log(settings);
    let fetcher: (prompt: string, settings: Settings, log: LogAction) => AsyncGenerator<string>;

    if (settings.apiType === "beam") {
        fetcher = beamStreamAPI;
    }

    const throttledTokensToTopic = throttle(250, (buffer: string) => {
        try {
            // console.log("-");
            feed(tokensToTopic(topicId, buffer));
            // console.log("_");
        } catch (e) {
            // --
        }
    }, {noLeading: true, noTrailing: false, debounceMode: false});

    let buffer = "";
    for await (const tokens of fetcher("", settings, log)) {
        // console.log(".");
        buffer += tokens;
        throttledTokensToTopic(buffer);
    }

    throttledTokensToTopic.cancel();

    // console.log("loool")

    feed(tokensToTopic(topicId, buffer));
}

export async function feedPosts(
    settings: Settings,
    log: LogAction,
    topic: Topic,
    feed: (topic: Topic) => void // topic with posts added
): Promise<void> {
    // TODO: to avoid too long context:
    // If the topic exceed a certain amount of posts -> only take the 3 first post and the 3 last to generate the context
    const context = tokenizeTopic(topic);

    let fetcher: (prompt: string, settings: Settings, log: LogAction) => AsyncGenerator<string>;

    if (settings.apiType === "beam") {
        fetcher = beamStreamAPI;
    }

    const throttledTokensToTopic = throttle(250, (buffer: string) => {
        try {
            // console.log("-");
            feed(tokensToTopic(topic.id, buffer));
            // console.log("_");
        } catch (e) {
            // --
        }
    }, {noLeading: true, noTrailing: false, debounceMode: false});

    let buffer = context;
    for await (const tokens of fetcher(context, settings, log)) {
        // console.log(".");
        buffer += tokens;
        throttledTokensToTopic(buffer);
    }

    throttledTokensToTopic.cancel();

    feed(tokensToTopic(topic.id, buffer));
}

function tokensToTopic(id: string, tokens: string): Topic {
    const topic: Topic = {
        id: id,
        title: "",
        posts: [],
    };

    // const splits = tokens.split("<|end_of_post|>")
    // console.log("Splits:")
    // console.log(splits);

    // Split token in posts
    // The last element is always vois, so remove it
    for(const postTokens of tokens.split("<|end_of_post|>").slice(0, -1)) {
        // console.log("Post tokens:")
        // console.log(postTokens);

        // If it's the first post
        if(topic.posts.length < 1) {
            const titleMatch = postTokens.match(titleRegex);
            if(!titleMatch) throw new Error("Impossible de trouver le titre du sujet");
            // console.log(`title: ${titleMatch[1]}`)

            topic.title = titleMatch[1];
        }

        // topic.posts.push(tokensToPosts());
        topic.posts = topic.posts.concat(tokensToPosts(postTokens));
    }

    return topic;
}

function tokensToPosts(tokens: string): Post[] {
    const posts: Post[] = [];

    for(const postTokens of tokens.split("<|end_of_post|>")) {

        // TODO: remove the last instead of doing this, because the last can be incomplete
        if(postTokens.length < 1) {
            continue;
        }

        // console.log("Post tokens:")
        // console.log(postTokens);

        const userMatch = postTokens.match(userRegex);
        if(!userMatch) throw new Error("Impossible de trouver le nom de l'auteur du message");
        // console.log(`user: ${userMatch[1]}`)

        const dateMatch = postTokens.match(dateRegex);
        if(!dateMatch) throw new Error("Impossible de trouver la date du message");
        // console.log(`date: ${dateMatch[1]}`)

        const contentMatch = postTokens.match(contentRegex);
        if(!contentMatch) throw new Error("Impossible de trouver le contenu du message");
        // console.log(`content: ${contentMatch[1]}`)

        posts.push({
            user: userMatch[1],
            date: frenchToIso8601(dateMatch[1]),
            generationDate: getCurrentTimeIso8601(),
            content: contentMatch[1],
        });
    }

    return posts;
}


function tokenizeTopic(topic: Topic): string {
    if (topic.posts.length === 0) {
        throw new Error("Topic must have at least one post")
    }

    const tokenizedPosts = topic.posts.map(post => tokenizePost(post, topic.posts[0].user)).flat().join("");

    // console.log("Tokenized posts:")
    // console.log(tokenizedPosts)

    let lines = [
        "<|start_header_id|><|sujet|><|end_header_id|>",
        "",
        `Sujet : "${topic.title}"`,
    ];

    return lines.join("\n") + tokenizedPosts;
}

function tokenizePost(post: Post, poster: string): string {
    let lines = [
        `<|eot_id|><|start_header_id|><|${post.user === poster ? "autheur" : "khey"}|>`,
        "<|end_header_id|>",
        "",
        `<|im_pseudo|>${post.user}<|end_pseudo|>`,
        `<|im_date|>Le ${iso8601ToFrench(post.date)}<|end_date|>`,
        "",
        `<|begin_of_post|>${post.content}<|end_of_post|>`
    ];

    return lines.join("\n");
}