#include <iostream>
#include <vector>
#include "histogram.h"
#include "svg.h"
#include <curl/curl.h>
#include <sstream>
#include <string>
using namespace std;

struct Input {
    vector<double> numbers;
    size_t bin_count;
    string stroke_color = "black";
};

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

size_t write_data(void* items, size_t item_size, size_t item_count, void* ctx) {
    stringstream* buffer = reinterpret_cast<stringstream*>(ctx);
    size_t data_size = item_size * item_count;
    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) {
        curl_easy_setopt(curl, CURLOPT_URL, address.c_str());
        curl_easy_setopt(curl, CURLOPT_WRITEFUNCTION, write_data);
        curl_easy_setopt(curl, CURLOPT_WRITEDATA, &buffer);
        CURLcode res = curl_easy_perform(curl);
        if (res != CURLE_OK) {
            cerr << curl_easy_strerror(res);
            exit(1);
        }
        curl_easy_cleanup(curl);
    }
    return input_data(buffer, false);
}

void parse_args(int argc, char* argv[], Input& input, string& url) {
    for (int i = 1; i < argc; i++) {
        string arg = argv[i];
        if (arg == "-stroke") {
            if (i + 1 < argc) {
                input.stroke_color = argv[i+1];
                i++;
            } else {
                cerr << "Error: require a color value" << endl;
                exit(1);
            }
        } else if (arg[0] != '-') {
            url = arg;
        } else {
            cerr << "Error: Unknown option " << arg << endl;
            exit(1);
        }
    }
}

int main(int argc, char* argv[]) {
    curl_global_init(CURL_GLOBAL_ALL);
    Input input;
    string url;
    if (argc > 1) {
        parse_args(argc, argv, input, url);
        if (!url.empty()) {
            Input downloaded = download(url);
            input.numbers = downloaded.numbers;
            input.bin_count = downloaded.bin_count;
        } else {
            input = input_data(cin, true);
        }
    } else {
        input = input_data(cin, true);
    }
    const auto bins = make_histogram(input.numbers, input.bin_count);
    show_histogram_svg(bins, input.stroke_color);
    curl_global_cleanup();
    return 0;
}