error scanner and flag modifier

update.js

errorScanAndModify = (item, flag, data) => {
    
    let expectedFlags;
    switch(item){
        case 'projects':
            expectedFlags = ['name', 'n', 'url', 'u', 'git', 'g', 'date', 'd'];
            break;
        case 'gitHub':
        case 'blog':
        case 'portfolio':
            expectedFlags = ['url', 'u'];
            break;
        case 'certifications':
            expectedFlags = ['url', 'u', 'date', 'd'];
            break;
    }

    if(!~expectedFlags.indexOf(flag)){
        return `invalid update flag [\`-${flag}\`] for update item [\`${item}\`].\n Try \`/update ${item}\` for a list of required and optional flags`
    }

    // modification step (as needed)
    switch(true){
        case flag === 'git' || flag === 'g':
            if(!data.includes('https://www.github.com/'))
                return `invalid data: \`${data}\` associated with flag [\`-${flag}\`] does not begin with \`https://www.github.com/\``;
            flag = 'gitHub';
            break;
        case flag === 'url' || flag === 'u':
            if(item === 'gitHub'){
                if(!data.includes('https://www.github.com/')) return `invalid gitHub profile url, ensure the url entered is of the form [\`https://www.github.com/yourUserName\`]`
            }
            if(!/(http:\/\/|https:\/\/)(www\.)/.test(data))
                return `invalid data: \`${data}\` associated with flag [\`-${flag}\`]. ensure the full [\`http://www.\`] or [\`https://www.\`] url is being passed`;
            flag = 'url';
            break;
        case flag === 'date' || flag === 'd':
            if(!/[0-9]{2}\/[0-9]{2}\/[0-9]{2}/.test(data))
                return `invalid date format [${data}]. must be in \`mm/dd/yy\` format`;
            data = Date.parse(new Date(data))/1000;
            flag = 'completedDate';
            break;
        case flag === 'n':
            flag = 'name';
            break;
    }

    return {data: data, flag: flag};
};