get-proxy-details.js

// identifier(s) should be in the following format:
// {
//     resultName: 'name of key that will be used in the returned object',
//     identifier: 'identifier that will be searched for in the format'
// }
function breakDown(string, format, identifiers){
    for(let i = 0; i < identifiers.length; i++){
        const identifier = identifiers[i];
        identifier.index = format.indexOf(identifier.identifier);
    }
    identifiers = identifiers.sort((a, b)=>{return a.index - b.index})          // sort the indexes in ascending order
                             .filter((object)=>{return object.index !== -1});   // remove the indexes that weren't found (not found means index value of -1)

    if(identifiers.length > 0){
        identifiers[0].leftSideCharacters = format.slice(0, identifiers[0].index);
        for(let i = 0; i < identifiers.length; i++){ // this will handle all the characters between the identifiers
            const {identifier, index} = identifiers[i];

            if(i + 1 !== identifiers.length){ // this is not the last array item
                const nextIndex = identifiers[i + 1].index; // we can use i + 1 because it will never return undefined because we skip the last item
                const characters = format.slice(index + identifier.length, nextIndex);
                identifiers[i].rightSideCharacters = characters;
                identifiers[i + 1].leftSideCharacters = characters;
            }
        }
        const previousItem = identifiers[identifiers.length - 1];
        previousItem.rightSideCharacters = format.slice(previousItem.index + previousItem.identifier.length);
    }

    let finished = false;
    const brokenDown = {};
    for(let i = 0; i < identifiers.length; i++){
        const item = identifiers[i];
        const {resultName, leftSideCharacters, rightSideCharacters} = identifiers[i];
        const previousItem = identifiers[i - 1];

        const leftSideCharactersIndex = previousItem === undefined ? leftSideCharacters.length : previousItem.rightSideCharactersIndex + previousItem.rightSideCharacters.length;
        let rightSideCharactersIndex = rightSideCharacters === '' ? string.length : string.indexOf(rightSideCharacters, leftSideCharactersIndex);
        if(rightSideCharactersIndex === -1){
            rightSideCharactersIndex = string.length;
        }
        item.rightSideCharactersIndex = rightSideCharactersIndex;

        if(finished){
            brokenDown[resultName] = null;
            continue;
        }

        brokenDown[resultName] = string.slice(leftSideCharactersIndex, rightSideCharactersIndex);

        if(rightSideCharactersIndex === string.length){
            finished = true;
        }
    }

    return brokenDown;
}

function getProxyDetails(proxy, format){
    return breakDown(proxy, format, [
        {
            resultName: 'address',
            identifier: '#address#'
        },
        {
            resultName: 'port',
            identifier: '#port#'
        },
        {
            resultName: 'username',
            identifier: '#username#'
        },
        {
            resultName: 'password',
            identifier: '#password#'
        }
    ]);
}