//SPDX-FileCopyrightText: 2023 Yury Gubich <blue@macaw.me>
//SPDX-License-Identifier: GPL-3.0-or-later

#include "router.h"

#include "request/redirect.h"

Router::Router():
    get(),
    post()
{}

void Router::addRoute(Handler handler) {
    std::pair<std::map<std::string, Handler>::const_iterator, bool> result;
    switch (handler->method) {
        case Request::Method::get:
            result = get.emplace(handler->path, std::move(handler));
            break;
        case Request::Method::post:
            result = post.emplace(handler->path, std::move(handler));
            break;
        default:
            throw std::runtime_error("An attempt to register handler with unsupported method type: " + std::to_string((int)handler->method));
    }

    if (!result.second)
        throw std::runtime_error("could'not add route " + handler->path + " to the routing table");
}

void Router::route(std::unique_ptr<Request> request) {
    std::map<std::string, Handler>::const_iterator itr, end;
    switch (request->method()) {
        case Request::Method::get:
            itr = get.find(request->getPath());
            end = get.end();
            break;
        case Request::Method::post:
            itr = post.find(request->getPath());
            end = post.end();
            break;
        default:
            return handleMethodNotAllowed(std::move(request));
    }

    if (itr == end)
        return handleNotFound(std::move(request));

    try {
        itr->second->handle(*request.get());

        if (request->currentState() != Request::State::responded)
            handleInternalError(std::runtime_error("handler failed to handle the request"), std::move(request));
    } catch (const Redirect& redirect) {
        redirect.destination->accept(std::move(request));
    } catch (const std::exception& e) {
        handleInternalError(e, std::move(request));
    }
}

void Router::handleNotFound(std::unique_ptr<Request> request) {
    Response& notFound = request->createResponse(Response::Status::notFound);
    std::string path = request->getPath();
    notFound.setBody(std::string("Path \"") + path + "\" was not found");
    notFound.send();
    std::cerr << notFound.statusCode() << '\t' << request->methodName() << '\t' << path << std::endl;
}

void Router::handleInternalError(const std::exception& exception, std::unique_ptr<Request> request) {
    Response& error = request->createResponse(Response::Status::internalError);
    error.setBody(std::string(exception.what()));
    error.send();
    std::cerr << error.statusCode() << '\t' << request->methodName() << '\t' << request->getPath() << std::endl;
}

void Router::handleMethodNotAllowed(std::unique_ptr<Request> request) {
    Response& error = request->createResponse(Response::Status::methodNotAllowed);
    error.setBody(std::string("Method not allowed"));
    error.send();
    std::cerr << error.statusCode() << '\t' << request->methodName() << '\t' << request->getPath() << std::endl;
}