#include "SimpleHandlers.hpp"

#include "Response.hpp"

#include <array>
#include <cctype>
#include <memory>
#include <string>
#include <iomanip>
#include <sstream>
#include <iostream>
#include <stdexcept>

using namespace Response;

Handler::json Handler::klingerHandler(std::string const &arguments, std::string const &session, void *payload) {
    (void) payload;
    return simple_response("Bonjour!");
}

Handler::json Handler::wikiHandler(std::string const &arguments, std::string const &session, void *payload) {
    (void) payload;

    std::vector<json> linkAnnotations;
    linkAnnotations.emplace_back(create_annotation(Reply::AnnotationType::link, "Wikipedia"));
    linkAnnotations.emplace_back(create_annotation(Reply::AnnotationType::underline));

    std::vector<json> reply_vec;
    reply_vec.emplace_back(create_text("Visit "));
    reply_vec.emplace_back(create_text("https://eo.wikipedia.org/", std::move(linkAnnotations)));
    reply_vec.emplace_back(create_text(" today!"));

    return create_response(std::move(reply_vec), session, true);
}

Handler::json Handler::helpHandler(std::string const &arguments, std::string const &session, void *payload) {
    auto commands = (std::vector<CommandHandler> *) payload;

    std::vector<json> reply_vec;
    reply_vec.emplace_back(create_text(
            "Reading from the gospel according to saint N,\n"
            "And you shall feast upon the fruits and vegetables as I do in the offering for they will make you strong.\n"
            "\n"
            "Dear my fellow users, these are my official commands, which are offered to my believers.\n"
            "\n"));

    for (auto const &itor : *commands) {
        std::vector<json> commandAnnotations;

        commandAnnotations.emplace_back(
                create_annotation(Reply::AnnotationType::command, std::move(itor.get_description())));

        reply_vec.emplace_back(create_text("- "));
        reply_vec.emplace_back(create_text(itor.command, std::move(commandAnnotations)));
    }

    reply_vec.emplace_back(create_text(
            "\n"
            "Thanks for using me. Takk skal du ha.\n"
            "Bussy\n"
            "N"));

    return create_response(std::move(reply_vec), session, true);
}

Handler::json Handler::stopHandler(std::string const &arguments, std::string const &session, void *payload) {
    auto app = (crow::SimpleApp *) payload;

    auto args = tokenizeArguments(arguments);

    if (args.empty()) {
        return simple_response("Needs PIN!", session, true);
    }

    int admin_pin;
    std::ifstream infile("/root/.n_admin_pin");

    if (!(infile >> admin_pin) || admin_pin != std::stoi(args.at(0))) {
        return simple_response("No PIN registered on server, admin commands unavailable", session, true);
    }

    app->stop();

    std::vector<json> annotations;
    annotations.emplace_back(create_annotation(Reply::AnnotationType::bold));

    std::vector<json> reply_vec;
    reply_vec.emplace_back(create_text("stopped", std::move(annotations)));

    return create_response(std::move(reply_vec), session, true);
}

json Handler::sayHandler(const std::string &arguments, const std::string &session, void *payload) {
    (void) payload;
    return simple_response(arguments, session, true);
}

std::string url_encode(std::string const &value) {
    std::ostringstream escaped;
    escaped.fill('0');
    escaped << std::hex;

    for (char c : value) {
        // Keep alphanumeric and other accepted characters intact
        if (isalnum(c) || c == '-' || c == '_' || c == '.' || c == '~') {
            escaped << c;
            continue;
        }

        // Any other characters are percent-encoded
        escaped << std::uppercase;
        escaped << '%' << std::setw(2) << int((unsigned char) c);
        escaped << std::nouppercase;
    }

    return escaped.str();
}


std::string exec(const char* cmd) {
    std::array<char, 128> buffer{};
    std::string result;
    std::unique_ptr<FILE, decltype(&pclose)> pipe(popen(cmd, "r"), pclose);
    if (!pipe) {
        throw std::runtime_error("popen() failed!");
    }
    while (fgets(buffer.data(), buffer.size(), pipe.get()) != nullptr) {
        result += buffer.data();
    }
    return result;
}

json Handler::latexRenderHandler(std::string const &arguments, std::string const &session, void *payload) {
    (void) payload;

    std::string file = exec("mktemp");

    std::string result = exec(("curl -s 'https://latex.codecogs.com/png.latex?" + url_encode(arguments) + "' "
            "-H 'User-Agent: Mozilla/5.0 (Windows NT 10.0; rv:78.0) Gecko/20100101 Firefox/78.0' "
            "-H 'Accept: text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,*/*;q=0.8' "
            "-H 'Accept-Language: en-US,en;q=0.5' --compressed -H 'DNT: 1' -H 'Connection: keep-alive' "
            "-H 'Upgrade-Insecure-Requests: 1' --output " + file).c_str());

    return simple_response(result, session, true);
}