url.cpp

#include "url.h"
#include "str.h"
#include <format>

using namespace std;

const string prot_end("://");

url::url(const std::string& abs_url) : abs_url{abs_url} {

    string t = abs_url;

    // protocol
    size_t pidx = t.find(prot_end);
    if(pidx != string::npos) {
        protocol = t.substr(0, pidx);
        if(pidx + prot_end.size() < t.size()) {
            t = t.substr(pidx + prot_end.size());
        }
    }

    // host
    size_t hidx = t.find_first_of('/');
    if(hidx == string::npos) {
        host = t;
        t = "";
    }  else {
        host = t.substr(0, hidx);
        t = t.substr(hidx);
    }

    // query
    query = t;

    // parameters
    if(!t.empty()) {
        size_t ridx = query.find_first_of('?');
        if(ridx != string::npos && ridx + 1 < t.size()) {
            query_without_parameters = query.substr(0, ridx);
            t = query.substr(ridx + 1);
            vector<string> parts = str::split(t, "&");
            for(string& part : parts) {
                size_t eqidx = part.find_first_of('=');
                string key = part;
                string value;
                if(eqidx != string::npos && eqidx < part.size()) {
                    value = key.substr(eqidx + 1);
                    key = key.substr(0, eqidx);
                }
                parameters.emplace_back(key, value);
            }
        }
    }
}

std::string url::to_string() {
    string r = format("{}://{}{}", protocol, host, query_without_parameters);

    if(!parameters.empty()) {
        r += "?";
        for(int i = 0; i < parameters.size(); i++) {
            if(i > 0) r += "&";
            r += parameters[i].first;
            if(!parameters[i].second.empty()) {
                r += "=";
                r += parameters[i].second;
            }
        }
    }

    return r;
}