#include <iostream>
#include <vector>
#include <sstream>
#include <string>
#include <curl/curl.h>
#include "histogram.h"
#include "svg.h"

using namespace std;

struct Input
{
    vector<double> numbers;
    size_t bin_count{};
};

Input
input_data(istream& stream, bool prompt)
{
    size_t number_count;
    if (prompt) {
        cerr << "Enter number count: ";
    }
    stream >> number_count;
    Input in;
    in.numbers.resize(number_count);
    for (size_t i = 0; i < number_count; i++)
    {
        stream >> in.numbers[i];
    }
    if (prompt) {
        cerr << "Enter bin count: ";
    }
    stream >> in.bin_count;
    return in;
}

size_t write_data(void* items, size_t item_size, size_t item_count, void* ctx)
{
    size_t data_size = item_size * item_count;
    stringstream* buffer = reinterpret_cast<stringstream*>(ctx);
    buffer->write(reinterpret_cast<const char*>(items), data_size);
    return data_size;
}

Input download(const string& address) {
    stringstream buffer;
    CURL* curl = curl_easy_init();
        if (curl) {
            CURLcode res;
            curl_easy_setopt(curl, CURLOPT_URL, address.c_str());
            curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_data);
            curl_easy_setopt(curl, CURLOPT_WRITEDATA, &buffer);
            res = curl_easy_perform(curl);
            if (res != CURLE_OK) {
                fprintf(stderr, "curl_easy_perform() failed: %s\n", curl_easy_strerror(res));
                exit(1);
            }
            curl_easy_cleanup(curl);
        }
    return input_data(buffer, false);
}

int main(int argc, char* argv[]) {
    Input input;
    if (argc > 1) {
            input = download(argv[1]);
    }
    else {
        input = input_data(cin, true);
    }
    if (curl_version_info(CURLVERSION_NOW) != nullptr) {
        auto curl_ver = curl_version_info(CURLVERSION_NOW)->version;
        cerr << "cURL version " << curl_ver << "\n";
        auto ssl_ver = curl_version_info(CURLVERSION_NOW)->ssl_version;
        cerr << "SSL version " << ssl_ver << "\n";
    } else{ cerr<<"curl_version_info() failed \n"; }
    vector<size_t> bins = make_histogram(input.numbers, input.bin_count);
    show_histogram_svg(bins);
}