import fs from "fs";
import $ from "./lib";

const Storage = {
    read(header: string): object {
        this.open("data");
        const path = `data/${header}.json`;
        let data = {};

        if (fs.existsSync(path)) {
            const file = fs.readFileSync(path, "utf-8");

            try {
                data = JSON.parse(file);
            } catch (error) {
                if (process.argv[2] !== "dev") {
                    $.warn(
                        `Malformed JSON data (header: ${header}), backing it up.`,
                        file
                    );
                    fs.writeFile(
                        `${path}.backup`,
                        file,
                        generateHandler(
                            `Backup file of "${header}" successfully written as ${file}.`
                        )
                    );
                }
            }
        }

        return data;
    },
    write(header: string, data: object, asynchronous = true) {
        this.open("data");
        const path = `data/${header}.json`;

        if (process.argv[2] === "dev" || header === "config") {
            const result = JSON.stringify(data, null, "\t");

            if (asynchronous)
                fs.writeFile(
                    path,
                    result,
                    generateHandler(
                        `"${header}" sucessfully spaced and written.`
                    )
                );
            else fs.writeFileSync(path, result);
        } else {
            const result = JSON.stringify(data);

            if (asynchronous)
                fs.writeFile(
                    path,
                    result,
                    generateHandler(`"${header}" sucessfully written.`)
                );
            else fs.writeFileSync(path, result);
        }
    },
    open(
        path: string,
        filter?: (value: string, index: number, array: string[]) => unknown
    ): string[] {
        if (!fs.existsSync(path)) fs.mkdirSync(path);

        let directory = fs.readdirSync(path);

        if (filter) directory = directory.filter(filter);

        return directory;
    },
    close(path: string) {
        if (fs.existsSync(path) && fs.readdirSync(path).length === 0)
            fs.rmdir(path, generateHandler(`"${path}" successfully closed.`));
    }
};

export function generateHandler(message: string) {
    return (error: Error | null) => {
        if (error) $.error(error);
        else $.debug(message);
    };
}

export default Storage;