const { promises: fs } = require("fs");
const path = require("path");
const { html: beautifyHtml } = require('js-beautify');

const buildConfig = require("./buildconfig");

// source: https://stackoverflow.com/a/41407246
const escapeCodes = {
    reset: "\x1b[0m",
    bright: "\x1b[1m",
    dim: "\x1b[2m",
    underscore: "\x1b[4m",
    blink: "\x1b[5m",
    reverse: "\x1b[7m",
    hidden: "\x1b[8m",

    fgBlack: "\x1b[30m",
    fgRed: "\x1b[31m",
    fgGreen: "\x1b[32m",
    fgYellow: "\x1b[33m",
    fgBlue: "\x1b[34m",
    fgMagenta: "\x1b[35m",
    fgCyan: "\x1b[36m",
    fgWhite: "\x1b[37m",

    bgBlack: "\x1b[40m",
    bgRed: "\x1b[41m",
    bgGreen: "\x1b[42m",
    bgYellow: "\x1b[43m",
    bgBlue: "\x1b[44m",
    bgMagenta: "\x1b[45m",
    bgCyan: "\x1b[46m",
    bgWhite: "\x1b[47m",
};

if (!buildConfig.allowSpecialCharacters) {
    for (i in escapeCodes) {
        escapeCodes[i] = "";
    }
}

const specialCharacter = (c) => {
    if (buildConfig.allowSpecialCharacters) {
        return c;
    }
    return "";
}

const processPageOutput = async (out) => {
    if (typeof out === "function")
        out = await out();
    if (typeof out !== "string")
        throw new Error("got non-string page output (maybe one of the pages isn't exporting a string?)");

    if (buildConfig.postProcessing.trimOutput) {
        out = out.trim();
    }

    if (buildConfig.postProcessing.beautifyOutput) {
        out = beautifyHtml(out, buildConfig.postProcessing.beautifyOutputOptions);
    }

    return out;
};

const findAllPages = async (directory) =>
    (await fs.readdir(directory))
    .filter(
        f => f.endsWith(buildConfig.pageExtension)
    )
    .map(f => directory + "/" + f); // TODO: hack

const buildPage = async (pagePath) => {
    const processed = await processPageOutput(require(pagePath));
    console.log(`${escapeCodes.fgGreen}${specialCharacter("→")}${escapeCodes.reset} Built ${escapeCodes.fgBlue}${path.parse(path.basename(pagePath, buildConfig.pageExtension)).name}${escapeCodes.reset}`);
    return processed
};

const buildAllPages = async (directory) =>
    await Promise.all((await findAllPages(directory))
    .map(
        async p => [p, (await buildPage(p))]
    ));

const exportAllPages = async (sourcePath, outputPath) => {
    const pages = await buildAllPages(sourcePath);
    for (const [pagePath, pageContent] of pages) {
        const pageName = path.parse(path.basename(pagePath, buildConfig.pageExtension)).name;
        await fs.writeFile(path.join(outputPath, pageName + ".html"), pageContent);
    }
    return pages.length;
};

const main = async () => {
    const startTime = new Date();
    const builtPages = await exportAllPages(buildConfig.sourceDirectory, buildConfig.outputDirectory);
    console.log(`${escapeCodes.fgGreen}${specialCharacter("✓")} Done! ${escapeCodes.fgBlue}Built ${builtPages} pages in ${((new Date()) - startTime)}ms.${escapeCodes.reset}`);
};

main();