Editing 文本转代码拼接

<!DOCTYPE html>
<html>

<head>
    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
    <meta charset="utf-8" />
    <title>文本转代码拼接</title>
</head>

<body>
    选择文本转代码拼接 <input type="file"/>
    <textarea style="height:80vh;width:100%;margin:1em 0;"></textarea>
</body>

</html>

document.querySelector("input").oninput = async function () {
    let file = this.files[0];
    if (file) {
        let fr = new FileReader();
        fr.onload = function (e) {
            let txt = e.target.result;
            let codes = text2code(txt);
            document.querySelector('textarea').value = codes.join('\n')
        }
        fr.readAsText(file);
    }
}

function text2code(text) {
    let result = [];
    let regex = /^( {4})+/;
    let lines = text.split('\n');
    for (let line of lines) {
        let match = line.match(regex);
        if (match) {
            let leadingSpaces = match[0];
            let numTabs = leadingSpaces.length / 4;
            let tabs = '\\t'.repeat(numTabs);
            line = line.replace(leadingSpaces, tabs);
            line = line.replace("'[", "\'[").replace("]'", "]\'");
        }
        result.push(`codes.push('${line.trim()}');`);
    }
    return result;
}