"use strict";

// Public modules from npm
import luxon from "luxon";

// Modules from files
import HandiWork from "../classes/handiwork/handiwork.js";
import Thread from "../classes/thread.js";
import { IBasic, TAuthor, TEngine, TExternalPlatform, TStatus } from "../interfaces.js";
import shared, { TPrefixDict } from "../shared.js";
import { ILink, IPostElement } from "./post-parse.js";

/**
 * Gets information of a particular handiwork from its thread.
 * 
 * If you don't want to specify the object type, use `HandiWork`.
 * 
 * @todo It does not currently support assets.
 */
export default async function getHandiworkInformation<T extends IBasic>(url: string): Promise<T> {
    shared.logger.info(`Obtaining handiwork from ${url}`);

    // Fetch thread data
    const id = extractIDFromURL(url);
    const thread: Thread = new Thread(id);
    await thread.fetch();

    // Convert the info from thread to handiwork
    const hw: HandiWork = {} as HandiWork;
    hw.id = thread.id;
    hw.url = thread.url;
    hw.name = thread.title;
    hw.category = thread.category;
    hw.threadPublishingDate = thread.publication;
    hw.lastThreadUpdate = thread.modified;
    hw.tags = thread.tags;
    hw.rating = thread.rating;
    fillWithPrefixes(hw, thread.prefixes);

    // Fetch info from first post
    const post = await thread.getPost(1);
    fillWithPostData(hw, post.body);
    
    return <T><unknown>hw;
};

//#region Private methods

//#region Utilities

/**
 * Extracts the work's unique ID from its URL.
 */
function extractIDFromURL(url: string): number {
    shared.logger.trace("Extracting ID from URL...");

    // URL are in the format https://f95zone.to/threads/GAMENAME-VERSION-DEVELOPER.ID/
    // or https://f95zone.to/threads/ID/
    const match = url.match(/([0-9]+)(?=\/|\b)(?!-|\.)/);
    if (!match) return -1;

    // Parse and return number
    return parseInt(match[0], 10);
}

/**
 * Makes an array of strings uppercase.
 */
function toUpperCaseArray(a: string[]): string[] {
    /**
     * Makes a string uppercase.
     */
    function toUpper(s: string): string {
        return s.toUpperCase();
    }
    return a.map(toUpper);
}

/**
 * Check if the string `s` is in the dict `a`.
 * 
 * Case insensitive.
 */
function stringInDict(s: string, a: TPrefixDict): boolean {
    // Make uppercase all the strings in the array
    const values = toUpperCaseArray(Object.values(a));

    return values.includes(s.toUpperCase());
}

/**
 * Convert a string to a boolean.
 * 
 * Check also for `yes`/`no` and `1`/`0`.
 */
function stringToBoolean(s: string): boolean {
    // Local variables
    const positiveTerms = ["true", "yes", "1"];
    const negativeTerms = ["false", "no", "0"];
    const cleanString = s.toLowerCase().trim();
    let result = Boolean(s);

    if (positiveTerms.includes(cleanString)) result = true;
    else if (negativeTerms.includes(cleanString)) result = false;
    return result;
}

/**
 * Gets the element with the given name or `undefined`.
 * 
 * Case-insensitive.
 */
function getPostElementByName(elements: IPostElement[], name: string): IPostElement | undefined {
    return elements.find(el =>  el.name.toUpperCase() === name.toUpperCase());
}

//#endregion Utilities

/**
 * Parse the post prefixes.
 * 
 * In particular, it elaborates the following prefixes for games:
 * `Engine`, `Status`, `Mod`.
 */
function fillWithPrefixes(hw: HandiWork, prefixes: string[]) {
    shared.logger.trace("Parsing prefixes...");

    // Local variables
    let mod = false;
    let engine: TEngine = null;
    let status: TStatus = null;

    /**
     * Emulated dictionary of mod prefixes.
     */
    const fakeModDict: TPrefixDict = {
        0: "MOD",
        1: "CHEAT MOD",
    }

    // Initialize the array
    hw.prefixes = [];

    prefixes.map((item, idx) => {
        // Remove the square brackets
        const prefix = item.replace("[", "").replace("]", "");

        // Check what the prefix indicates
        if (stringInDict(prefix, shared.prefixes["engines"])) engine = prefix as TEngine;
        else if (stringInDict(prefix, shared.prefixes["statuses"])) status = prefix as TStatus;
        else if (stringInDict(prefix, fakeModDict)) mod = true;

        // Anyway add the prefix to list
        hw.prefixes.push(prefix);
    });

    // If the status is not set, then the game is in development (Ongoing)
    status = (!status && hw.category === "games") ? status : "Ongoing";

    hw.engine = engine;
    hw.status = status;
    hw.mod = mod;
}

/**
 * Compiles a HandiWork object with the data extracted
 * from the main post of the HandiWork page.
 * 
 * The values that will be added are:
 * `Overview`, `OS`, `Language`, `Version`, `Installation`,
 * `Pages`, `Resolution`, `Lenght`, `Genre`, `Censored`,
 * `LastRelease`, `Authors`, `Changelog`, `Cover`.
 */
function fillWithPostData(hw: HandiWork, elements: IPostElement[]) {
    // First fill the "simple" elements
    hw.overview = getPostElementByName(elements, "overview")?.text;
    hw.os = getPostElementByName(elements, "os")?.text?.split(",").map(s => s.trim());
    hw.language = getPostElementByName(elements, "language")?.text?.split(",").map(s => s.trim());
    hw.version = getPostElementByName(elements, "version")?.text;
    hw.installation = getPostElementByName(elements, "installation")?.content.shift()?.text;
    hw.pages = getPostElementByName(elements, "pages")?.text;
    hw.resolution = getPostElementByName(elements, "resolution")?.text?.split(",").map(s => s.trim());
    hw.lenght = getPostElementByName(elements, "lenght")?.text;

    // Parse the censorship
    const censored = getPostElementByName(elements, "censored") || getPostElementByName(elements, "censorship");
    if (censored) hw.censored = stringToBoolean(censored.text);

    // Get the genres
    const genre = getPostElementByName(elements, "genre")?.content.shift()?.text;
    hw.genre = genre?.split(",").map(s => s.trim());

    // Get the cover
    const cover = getPostElementByName(elements, "overview")?.content.find(el => el.type === "Image") as ILink;
    hw.cover = cover?.href;

    // Fill the dates
    const releaseDate = getPostElementByName(elements, "release date")?.text;
    if (luxon.DateTime.fromISO(releaseDate).isValid) hw.lastRelease = new Date(releaseDate);

    //#region Convert the author
    const authorElement = getPostElementByName(elements, "developer") ||
        getPostElementByName(elements, "developer/publisher") ||
        getPostElementByName(elements, "artist");
    const author: TAuthor = {
        name: authorElement.text,
        platforms: []
    };

    // Add the found platforms
    authorElement?.content.forEach((el: ILink, idx) => {
        const platform: TExternalPlatform = {
            name: el.text,
            link: el.href,
        };

        author.platforms.push(platform);
    });
    hw.authors = [author];
    //#endregion Convert the author

    //#region Get the changelog
    hw.changelog = [];
    const changelogElement = getPostElementByName(elements, "changelog") || getPostElementByName(elements, "change-log");
    const changelogSpoiler = changelogElement?.content.find(el => {
        return el.type === "Spoiler" && el.content.length > 0;
    });

    // Add to the changelog the single spoilers
    changelogSpoiler.content.forEach(el => {
        if (el.text.trim()) hw.changelog.push(el.text);
    });

    // Add at the ened also the text of the "changelog" element
    hw.changelog.push(changelogSpoiler.text);
    //#endregion Get the changelog
}

//#endregion Private methods