#include <ctype.h>
#include <netdb.h>
#include <netinet/in.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/un.h>
#include <unistd.h>
#include <ranges>
#include <algorithm>
#include <signal.h>
#include <format>

#include <iostream>
#include <string>
#include <fstream>
#include <string>
#include <vector>
#include <deque>
#include <filesystem>
#include <stdarg.h>

const std::string USAGE = R"#(usage: hyprctl [(opt)flags] [command] [(opt)args]

commands:
    activewindow
    activeworkspace
    binds
    clients
    configerrors
    cursorpos
    decorations
    devices
    dismissnotify
    dispatch
    getoption
    globalshortcuts
    hyprpaper
    instances
    keyword
    kill
    layers
    layouts
    monitors
    notify
    output
    plugin
    reload
    rollinglog
    setcursor
    seterror
    setprop
    splash
    switchxkblayout
    systeminfo
    version
    workspacerules
    workspaces

flags:
    -j -> output in JSON
    -r -> refresh state after issuing command (e.g. for updating variables)
    --batch -> execute a batch of commands, separated by ';'
    --instance (-i) -> use a specific instance. Can be either signature or index in hyprctl instances (0, 1, etc)
)#";

#define PAD

std::string instanceSignature;

struct SInstanceData {
    std::string id;
    uint64_t    time;
    uint64_t    pid;
    std::string wlSocket;
    bool        valid = true;
};

std::vector<SInstanceData> instances() {
    std::vector<SInstanceData> result;

    for (const auto& el : std::filesystem::directory_iterator("/tmp/hypr")) {
        if (el.is_directory() || !el.path().string().ends_with(".lock"))
            continue;

        // read lock
        SInstanceData* data = &result.emplace_back();
        data->id            = el.path().string();
        data->id            = data->id.substr(data->id.find_last_of('/') + 1, data->id.find(".lock") - data->id.find_last_of('/') - 1);

        try {
            data->time = std::stoull(data->id.substr(data->id.find_first_of('_') + 1));
        } catch (std::exception& e) { continue; }

        // read file
        std::ifstream ifs(el.path().string());

        int           i = 0;
        for (std::string line; std::getline(ifs, line); ++i) {
            if (i == 0) {
                try {
                    data->pid = std::stoull(line);
                } catch (std::exception& e) { continue; }
            } else if (i == 1) {
                data->wlSocket = line;
            } else
                break;
        }

        ifs.close();
    }

    std::erase_if(result, [&](const auto& el) { return kill(el.pid, 0) != 0 && errno == ESRCH; });

    std::sort(result.begin(), result.end(), [&](const auto& a, const auto& b) { return a.time < b.time; });

    return result;
}

void request(std::string arg, int minArgs = 0) {
    const auto SERVERSOCKET = socket(AF_UNIX, SOCK_STREAM, 0);

    const auto ARGS = std::count(arg.begin(), arg.end(), ' ');

    if (ARGS < minArgs) {
        std::cout << "Not enough arguments, expected at least " << minArgs;
        return;
    }

    if (SERVERSOCKET < 0) {
        std::cout << "Couldn't open a socket (1)";
        return;
    }

    if (instanceSignature.empty()) {
        std::cout << "HYPRLAND_INSTANCE_SIGNATURE was not set! (Is Hyprland running?)";
        return;
    }

    sockaddr_un serverAddress = {0};
    serverAddress.sun_family  = AF_UNIX;

    std::string socketPath = "/tmp/hypr/" + instanceSignature + "/.socket.sock";

    strncpy(serverAddress.sun_path, socketPath.c_str(), sizeof(serverAddress.sun_path) - 1);

    if (connect(SERVERSOCKET, (sockaddr*)&serverAddress, SUN_LEN(&serverAddress)) < 0) {
        std::cout << "Couldn't connect to " << socketPath << ". (3)";
        return;
    }

    auto sizeWritten = write(SERVERSOCKET, arg.c_str(), arg.length());

    if (sizeWritten < 0) {
        std::cout << "Couldn't write (4)";
        return;
    }

    std::string reply        = "";
    char        buffer[8192] = {0};

    sizeWritten = read(SERVERSOCKET, buffer, 8192);

    if (sizeWritten < 0) {
        std::cout << "Couldn't read (5)";
        return;
    }

    reply += std::string(buffer, sizeWritten);

    while (sizeWritten == 8192) {
        sizeWritten = read(SERVERSOCKET, buffer, 8192);
        if (sizeWritten < 0) {
            std::cout << "Couldn't read (5)";
            return;
        }
        reply += std::string(buffer, sizeWritten);
    }

    close(SERVERSOCKET);

    std::cout << reply;
}

void requestHyprpaper(std::string arg) {
    const auto SERVERSOCKET = socket(AF_UNIX, SOCK_STREAM, 0);

    if (SERVERSOCKET < 0) {
        std::cout << "Couldn't open a socket (1)";
        return;
    }

    if (instanceSignature.empty()) {
        std::cout << "HYPRLAND_INSTANCE_SIGNATURE was not set! (Is Hyprland running?)";
        return;
    }

    sockaddr_un serverAddress = {0};
    serverAddress.sun_family  = AF_UNIX;

    std::string socketPath = "/tmp/hypr/" + instanceSignature + "/.hyprpaper.sock";

    strncpy(serverAddress.sun_path, socketPath.c_str(), sizeof(serverAddress.sun_path) - 1);

    if (connect(SERVERSOCKET, (sockaddr*)&serverAddress, SUN_LEN(&serverAddress)) < 0) {
        std::cout << "Couldn't connect to " << socketPath << ". (3)";
        return;
    }

    arg = arg.substr(arg.find_first_of('/') + 1); // strip flags
    arg = arg.substr(arg.find_first_of(' ') + 1); // strip "hyprpaper"

    auto sizeWritten = write(SERVERSOCKET, arg.c_str(), arg.length());

    if (sizeWritten < 0) {
        std::cout << "Couldn't write (4)";
        return;
    }

    char buffer[8192] = {0};

    sizeWritten = read(SERVERSOCKET, buffer, 8192);

    if (sizeWritten < 0) {
        std::cout << "Couldn't read (5)";
        return;
    }

    close(SERVERSOCKET);

    std::cout << std::string(buffer);
}

void batchRequest(std::string arg) {
    std::string rq = "[[BATCH]]" + arg.substr(arg.find_first_of(" ") + 1);

    request(rq);
}

void instancesRequest(bool json) {
    std::string result = "";

    // gather instance data
    std::vector<SInstanceData> inst = instances();

    if (!json) {
        for (auto& el : inst) {
            result += std::format("instance {}:\n\ttime: {}\n\tpid: {}\n\twl socket: {}\n\n", el.id, el.time, el.pid, el.wlSocket);
        }
    } else {
        result += '[';
        for (auto& el : inst) {
            result += std::format(R"#(
{{
    "instance": "{}",
    "time": {},
    "pid": {},
    "wl_socket": "{}"
}},)#",
                                  el.id, el.time, el.pid, el.wlSocket);
        }

        result.pop_back();
        result += "\n]";
    }

    std::cout << result << "\n";
}

std::deque<std::string> splitArgs(int argc, char** argv) {
    std::deque<std::string> result;

    for (auto i = 1 /* skip the executable */; i < argc; ++i)
        result.push_back(std::string(argv[i]));

    return result;
}

bool isNumber(const std::string& str, bool allowfloat) {
    if (str.empty())
        return false;
    return std::ranges::all_of(str.begin(), str.end(), [&](char c) { return isdigit(c) != 0 || c == '-' || (allowfloat && c == '.'); });
}

int main(int argc, char** argv) {
    bool parseArgs = true;

    if (argc < 2) {
        printf("%s\n", USAGE.c_str());
        return 1;
    }

    std::string fullRequest      = "";
    std::string fullArgs         = "";
    const auto  ARGS             = splitArgs(argc, argv);
    bool        json             = false;
    std::string overrideInstance = "";

    for (std::size_t i = 0; i < ARGS.size(); ++i) {
        if (ARGS[i] == "--") {
            // Stop parsing arguments after --
            parseArgs = false;
            continue;
        }
        if (parseArgs && (ARGS[i][0] == '-') && !isNumber(ARGS[i], true) /* For stuff like -2 */) {
            // parse
            if (ARGS[i] == "-j" && !fullArgs.contains("j")) {
                fullArgs += "j";
                json = true;
            } else if (ARGS[i] == "-r" && !fullArgs.contains("r")) {
                fullArgs += "r";
            } else if (ARGS[i] == "-a" && !fullArgs.contains("a")) {
                fullArgs += "a";
            } else if (ARGS[i] == "--batch") {
                fullRequest = "--batch ";
            } else if (ARGS[i] == "--instance" || ARGS[i] == "-i") {
                ++i;

                if (i >= ARGS.size()) {
                    printf("%s\n", USAGE.c_str());
                    return 1;
                }

                overrideInstance = ARGS[i];
            } else {
                printf("%s\n", USAGE.c_str());
                return 1;
            }

            continue;
        }

        fullRequest += ARGS[i] + " ";
    }

    if (fullRequest.empty()) {
        printf("%s\n", USAGE.c_str());
        return 1;
    }

    fullRequest.pop_back(); // remove trailing space

    fullRequest = fullArgs + "/" + fullRequest;

    // instances is HIS-independent
    if (fullRequest.contains("/instances")) {
        instancesRequest(json);
        return 0;
    }

    if (overrideInstance.contains("_"))
        instanceSignature = overrideInstance;
    else if (!overrideInstance.empty()) {
        if (!isNumber(overrideInstance, false)) {
            std::cout << "instance invalid\n";
            return 1;
        }

        const auto INSTANCENO = std::stoi(overrideInstance);

        const auto INSTANCES = instances();

        if (INSTANCENO < 0 || static_cast<std::size_t>(INSTANCENO) >= INSTANCES.size()) {
            std::cout << "no such instance\n";
            return 1;
        }

        instanceSignature = INSTANCES[INSTANCENO].id;
    } else {
        const auto ISIG = getenv("HYPRLAND_INSTANCE_SIGNATURE");

        if (!ISIG) {
            std::cout << "HYPRLAND_INSTANCE_SIGNATURE not set! (is hyprland running?)\n";
            return 1;
        }

        instanceSignature = ISIG;
    }

    int exitStatus = 0;

    if (fullRequest.contains("/--batch"))
        batchRequest(fullRequest);
    else if (fullRequest.contains("/hyprpaper"))
        requestHyprpaper(fullRequest);
    else if (fullRequest.contains("/switchxkblayout"))
        request(fullRequest, 2);
    else if (fullRequest.contains("/seterror"))
        request(fullRequest, 1);
    else if (fullRequest.contains("/setprop"))
        request(fullRequest, 3);
    else if (fullRequest.contains("/plugin"))
        request(fullRequest, 1);
    else if (fullRequest.contains("/dismissnotify"))
        request(fullRequest, 0);
    else if (fullRequest.contains("/notify"))
        request(fullRequest, 2);
    else if (fullRequest.contains("/output"))
        request(fullRequest, 2);
    else if (fullRequest.contains("/setcursor"))
        request(fullRequest, 1);
    else if (fullRequest.contains("/dispatch"))
        request(fullRequest, 1);
    else if (fullRequest.contains("/keyword"))
        request(fullRequest, 2);
    else if (fullRequest.contains("/decorations"))
        request(fullRequest, 1);
    else if (fullRequest.contains("/--help"))
        printf("%s", USAGE.c_str());
    else {
        request(fullRequest);
    }

    printf("\n");
    return exitStatus;
}