#include <string.h>
#include <filesystem>
#include <unistd.h>
#include <sys/types.h>
#include <pwd.h>

#include <pistache/http.h>
#include <pistache/description.h>
#include <pistache/endpoint.h>

#include <pistache/serializer/rapidjson.h>

#include <bsoncxx/builder/stream/document.hpp>
#include <bsoncxx/json.hpp>

#include <mongocxx/client.hpp>
#include <mongocxx/instance.hpp>

#include <mongocxx/client.hpp>
#include <mongocxx/stdx.hpp>
#include <mongocxx/uri.hpp>

#include <json-c/json.h>

#include <fstream>
#include <nlohmann/json.hpp>

#include "clara.hpp"
#include "shared.h"

std::map<std::string, std::string> config;

using namespace std;
using namespace Pistache;

using bsoncxx::builder::stream::close_array;
using bsoncxx::builder::stream::close_document;
using bsoncxx::builder::stream::document;
using bsoncxx::builder::stream::finalize;
using bsoncxx::builder::stream::open_array;
using bsoncxx::builder::stream::open_document;

using json = nlohmann::json;

using namespace clara;

namespace Generic {
    void handleReady(const Rest::Request&, Http::ResponseWriter response) {
        response.send(Http::Code::Ok, "1");
    }
}

void load_config(string config_path) {
std::ifstream is_file(config_path);
    std::string line;
    while( std::getline(is_file, line) )
    {
      std::istringstream is_line(line);
      std::string key;
      if( std::getline(is_line, key, '=') )
      {
          std::string value;
          if( std::getline(is_line, value) )
             config[key] = value;
        }
    }
    is_file.close();

    string mongoURI = "mongodb://";


    if (config["mongo_db"] == "") {
        config["mongo_db"] = "umosapi";
    }

    if (config["mongo_user"] != "") {
        mongoURI.append(config["mongo_user"] + ":");
    }

    if (config["mongo_password"] != "") {
        mongoURI.append(config["mongo_password"] + "@");
    }

    if (config["mongo_host"] == "") {
        config["mongo_host"] = "127.0.0.1";
    }
    mongoURI.append(config["mongo_host"]);

    if (config["mongo_port"] == "") {
        config["mongo_port"] = "umosapi";
    }
    mongoURI.append(":" + config["mongo_port"]);

    if (config["swaggerui"] == "") {
        config["swaggerui"] = "/srv/http/swagger-ui";
    }

    config["mongoURI"] = mongoURI;

}

class UmosapiService {
    public:

        UmosapiService(Address addr)
            : httpEndpoint(std::make_shared<Http::Endpoint>(addr))
            , desc("Unity Mongo Save API", "0.1")
        { }

        void init(size_t thr = 2) {
            auto opts = Http::Endpoint::options()
                .threads(thr);
            httpEndpoint->init(opts);
            createDescription();
        }

        void start(std::string swaggerui) {
            router.initFromDescription(desc);

            Rest::Swagger swagger(desc);
            swagger
                .uiPath("/doc")
                .uiDirectory(swaggerui)
                .apiPath("/api")
                .serializer(&Rest::Serializer::rapidJson)
                .install(router);

            httpEndpoint->setHandler(router.handler());
            httpEndpoint->serve();
        }

    private:
        void createDescription() {
            desc
                .info()
                .license("Apache", "https://neodarz.net");

            auto backendErrorResponse =
                desc.response(Http::Code::Internal_Server_Error, "Backend is dead, it's the end of the world");

            desc
                .schemes(Rest::Scheme::Http)
                .basePath("/v1")
                .produces(MIME(Application, Json))
                .consumes(MIME(Application, Json));

            desc
                .route(desc.get("/ready"))
                .bind(&Generic::handleReady)
                .response(Http::Code::Ok, "Api started")
                .response(backendErrorResponse);

            auto versionPath = desc.path("/v1");

            versionPath
                .route(desc.get("/:mcollection"))
                .bind(&UmosapiService::retrieveAll, this)
                .produces(MIME(Application, Json))
                .parameter<Rest::Type::String>("mcollection", "Name of the collection where the uobjects are located")
                .response(Http::Code::Ok, "List of uobjects")
                .response(backendErrorResponse);

        }

        void retrieveAll(const Rest::Request& request, Http::ResponseWriter response) {
            mongocxx::client conn{mongocxx::uri{config["mongoURI"]}};

            auto collection = conn[config["mongo_db"]][request.param(":mcollection").as<string>()];

            auto cursor = collection.find({});

            auto jsonObjects = json_object_new_array();

            for (auto&& doc : cursor) {
                json_object_array_add(jsonObjects, json_tokener_parse(bsoncxx::to_json(doc).c_str()));
            }

            response.send(Http::Code::Ok, json_object_to_json_string_ext(jsonObjects, JSON_C_TO_STRING_SPACED | JSON_C_TO_STRING_PRETTY), MIME(Application, Json));
            json_object_put(jsonObjects);
        }

        std::shared_ptr<Http::Endpoint> httpEndpoint;
        Rest::Description desc;
        Rest::Router router;
};


int main(int argc, char *argv[]) {

    string config_path = "";
    const char *homedir;

    if ((homedir = getenv("XDG_CONFIG_HOME")) == NULL || (homedir = getenv("HOME")) == NULL) {
        homedir = getpwuid(getuid())->pw_dir;
    }

    config_path.append(homedir);
    config_path.append("/.config/umosapi/config.txt");

    bool showHelp = false;
    int config_port = 9080;
    int thr = 2;
    auto cli = clara::detail::Help(showHelp)
             | clara::detail::Opt( config_path, "config" )["-c"]["--config"]("Config file path. Default `~/.config/umosapi/config.txt`.")
             | clara::detail::Opt( config_port, "port" )["-p"]["--port"]("Port to listen. Default: `9080`.")
             | clara::detail::Opt( thr, "treads" )["-t"]["--threads"]("Number of threads. Default: `2`.");
    auto result = cli.parse( clara::detail::Args( argc, argv ) );
    if( !result )
    {
        std::cerr << "Error in command line: " << result.errorMessage() << std::endl;
        std::cerr << cli << std::endl;
        exit(1);
    }

    if ( showHelp ) {
        std::cerr << cli << std::endl;
        exit(1);
    }

    Address addr(Ipv4::any(), Port(config_port));

    cout << "Using " << hardware_concurrency() << " cores";
    cout << " - " << thr << " threads" << endl;
    cout << "Listen on 0.0.0.0:" << config_port << endl;

    cout << "Using config file '" << config_path << "'" << endl;

    if (!std::filesystem::exists(config_path)) {
        cout << "Error fatal : config file '" << config_path << "' not found" << endl;
        cout << "config.txt is search here: ~/.config/umosapi/config.txt" << endl;
        exit (EXIT_FAILURE);
    }

    load_config(config_path);

    cout << "Using swaggerui " << config["swaggerui"] << " path" << endl;
    cout << "Using mongoURI " << config["mongoURI"] << endl;

    UmosapiService umosapi(addr);

    umosapi.init(thr);
    umosapi.start(config["swaggerui"]);
}