import sass from 'sass-embedded';
import path from 'path';
import chalk from 'chalk';
import emojiRegex from 'emoji-regex';

import _scss_fonts_builder from './_fonts';
let _scss_fonts: any = null;
import _scss_import_builder from './_import';
let _scss_import: any = null;

async function compileScssCode(scssCode: string, fileRootDir: string, minify: boolean = false): Promise<{
    code: string,
    dependencies: string[]
}> {  
    _scss_fonts = _scss_fonts_builder(this);
    _scss_import = _scss_import_builder(this);

    const [scssImports] = _scss_import.extractScssImports(scssCode, fileRootDir);
    
    const dependencies = scssImports.map((item) => item[2]);

    if (scssImports && scssImports.length) {
        scssCode = _scss_import.replaceImports(_scss_import.processImports(scssImports, fileRootDir), scssCode);
    }

    const uses = _scss_import.extractScssUses(scssCode)[0];
    let scssUses = '';
    uses.forEach(scssUse => {
        const useLine = scssUse[1];
        if(scssCode.indexOf(useLine) === -1){                
            scssUses += useLine + '\n';
            scssCode = scssCode.replace(useLine + '\n', '');
        }
    });

    scssCode = removeComments(scssUses + scssCode);

    try {                    

        const result: sass.CompileResult = await sass.compileStringAsync(scssCode, {
            loadPaths: [fileRootDir],
            style: minify ? "compressed" : "expanded",
            sourceMap: false
        });

        let compiledCode = result.css.toString();

        compiledCode = _scss_fonts.replaceFontUrlWithBase64(compiledCode);
        compiledCode = replaceEmojisWithQuestionMark(compiledCode, fileRootDir);
        return { code: compiledCode, dependencies };
    } catch (err) {
        console.error('SASS Error in', fileRootDir);
        console.error(err);
        throw err;
    }
}

function checkForImporterType(_module, checkTypeExt) {
    let importingFileExtension = '';
    if (_module && _module.issuer && _module.issuer.resource) {
        importingFileExtension = path.extname(_module.issuer.resource);
        if (importingFileExtension === ('.' + checkTypeExt)) {
            return true;
        }
    } else {
        return false;
    }
    return false
}

function replaceEmojisWithQuestionMark(code, componentDir) {
    const regex = emojiRegex();
    let hasEmoji = false;
    const result = code.replace(regex, (match) => {
        hasEmoji = true;
        return '?';
    });
    if (hasEmoji) {
        console.log(chalk.yellow(`Emojis in css detected and replaced with "?" in "${path.dirname(componentDir)}" component`));
    }
    return result;
}

function removeComments(code) {
    code = code.replace(/\/\/.*$/gm, '');
    code = code.replace(/\/\*[\s\S]*?\*\//g, '');
    code = code.replace(/^\s*$(?:\r\n?|\n)/gm, '');
    return code;
}

export default function(element) {
    return {
        checkForImporterType: checkForImporterType.bind(element),
        compileScssCode: compileScssCode.bind(element)
    };
};