#include "mainwindow.h"
#include "ui_mainwindow.h"

#include "algo.h"

#include <QMessageBox>
#include <QSignalBlocker>

#include <algorithm>

bool CaseInsensitiveLess(const std::string& lhs, const std::string& rhs) {
    return QString::compare(
        QString::fromStdString(lhs),
        QString::fromStdString(rhs),
        Qt::CaseInsensitive
    ) < 0;
}

MainWindow::MainWindow(QWidget *parent)
    : QMainWindow(parent)
    , ui(new Ui::MainWindow)
    , m_random_gen_(std::random_device{}()) {
    ui->setupUi(this);

    ApplyModel();
}

MainWindow::~MainWindow() {
    delete ui;
}

void MainWindow::ApplyModel() {
    const auto it_tmp = deque_model_.iterator;
    const QSignalBlocker blocker(ui->list_widget);

    ui->list_widget->clear();

    for (size_t i = 0; i < deque_model_.items.size(); ++i) {
        ui->list_widget->addItem(
            QString::fromStdString(std::to_string(i) + ": " + deque_model_.items[i])
        );
    }

    ui->list_widget->addItem("end");

    deque_model_.iterator = it_tmp;

    ui->txt_size->setText(QString::number(deque_model_.items.size()));

    const bool is_empty = deque_model_.items.empty();
    ui->btn_pop_back->setDisabled(is_empty);
    ui->btn_pop_front->setDisabled(is_empty);
    ui->btn_erase->setDisabled(is_empty);

    ApplyIterator();
}

void MainWindow::ApplyIterator() {
    const QSignalBlocker blocker(ui->list_widget);

    if (deque_model_.items.empty()) {
        ui->list_widget->setCurrentRow(0);
        ui->txt_elem_content->clear();
        ui->btn_edit->setDisabled(true);
        ui->btn_erase->setDisabled(true);
        ui->btn_inc_iterator->setDisabled(true);
        ui->btn_dec_iterator->setDisabled(true);
        return;
    }

    const auto distance = std::distance(deque_model_.items.begin(), deque_model_.iterator);
    const bool is_end = deque_model_.iterator == deque_model_.items.end();
    const bool is_begin = deque_model_.iterator == deque_model_.items.begin();

    ui->list_widget->setCurrentRow(static_cast<int>(distance));
    ui->btn_edit->setDisabled(is_end);
    ui->btn_erase->setDisabled(is_end);
    ui->btn_inc_iterator->setDisabled(is_end);
    ui->btn_dec_iterator->setDisabled(is_begin);

    if (is_end) {
        ui->txt_elem_content->clear();
    } else {
        ui->txt_elem_content->setText(QString::fromStdString(*deque_model_.iterator));
    }
}

void MainWindow::SetRandomGen(const std::mt19937& random_gen) {
    m_random_gen_ = random_gen;
}

void MainWindow::on_btn_clear_clicked() {
    deque_model_.items.clear();
    deque_model_.iterator = deque_model_.items.begin();
    ApplyModel();
}

void MainWindow::on_btn_push_front_clicked() {
    deque_model_.items.push_front(ui->txt_elem_content->text().toStdString());

    deque_model_.iterator = deque_model_.items.begin();
    ApplyModel();
}

void MainWindow::on_btn_push_back_clicked() {
    deque_model_.items.push_back(ui->txt_elem_content->text().toStdString());
    deque_model_.iterator = deque_model_.items.begin();
    ApplyModel();
}

void MainWindow::on_btn_pop_back_clicked() {
    if (deque_model_.items.empty()) {
        return;
    }

    deque_model_.items.pop_back();
    deque_model_.iterator = deque_model_.items.begin();
    ApplyModel();
}

void MainWindow::on_btn_pop_front_clicked() {
    if (deque_model_.items.empty()) {
        return;
    }

    deque_model_.items.pop_front();
    deque_model_.iterator = deque_model_.items.begin();
    ApplyModel();
}

void MainWindow::on_btn_insert_clicked() {
    deque_model_.items.insert(
        deque_model_.iterator,
        ui->txt_elem_content->text().toStdString()
    );

    deque_model_.iterator = deque_model_.items.begin();
    ApplyModel();
}

void MainWindow::on_btn_erase_clicked() {
    if (deque_model_.iterator == deque_model_.items.end()) {
        return;
    }

    deque_model_.items.erase(deque_model_.iterator);
    deque_model_.iterator = deque_model_.items.begin();
    ApplyModel();
}

void MainWindow::on_btn_begin_clicked() {
    deque_model_.iterator = deque_model_.items.begin();
    ApplyIterator();
}

void MainWindow::on_btn_end_clicked() {
    deque_model_.iterator = deque_model_.items.end();
    ApplyIterator();
}

void MainWindow::on_btn_dec_iterator_clicked() {
    if (deque_model_.iterator != deque_model_.items.begin()) {
        --deque_model_.iterator;
    }

    ApplyIterator();
}

void MainWindow::on_btn_inc_iterator_clicked() {
    if (deque_model_.iterator != deque_model_.items.end()) {
        ++deque_model_.iterator;
    }

    ApplyIterator();
}

void MainWindow::on_list_widget_currentRowChanged(int currentRow) {
    currentRow = std::clamp(currentRow, 0, static_cast<int>(deque_model_.items.size()));
    deque_model_.iterator = deque_model_.items.begin() + currentRow;
    ApplyIterator();
}

void MainWindow::on_btn_tea_clicked() {
    static std::deque<std::string> tea {
        "Чай Лунцзин",
        "Эрл Грей",
        "Сенча",
        "Пуэр",
        "Дарджилинг",
        "Ассам",
        "Матча",
        "Ганпаудер",
        "Оолонг",
        "Лапсанг Сушонг"
    };

    deque_model_.items = tea;
    deque_model_.iterator = deque_model_.items.begin();
    ApplyModel();
}

void MainWindow::on_btn_cakes_clicked() {
    static std::deque<std::string> cakes {
        "Красный бархат",
        "Наполеон",
        "Медовик",
        "Тирамису",
        "Прага",
        "Чизкейк",
        "Захер",
        "Эстерхази",
        "Морковный торт",
        "Чёрный лес",
    };
    deque_model_.items = cakes;
    deque_model_.iterator = deque_model_.items.begin();
    ApplyModel();
}

void MainWindow::on_btn_edit_clicked() {
    if (deque_model_.iterator == deque_model_.items.end()) {
        return;
    }

    *deque_model_.iterator = ui->txt_elem_content->text().toStdString();
    ApplyModel();
}

void MainWindow::on_btn_resize_clicked() {
    bool ok = false;
    const int size = ui->txt_size->text().toInt(&ok);

    if (!ok || size < 0 || size > 1000) {
        QMessageBox::warning(this, "Error", "Incorrect size");
        return;
    }

    deque_model_.items.resize(static_cast<size_t>(size));
    deque_model_.iterator = deque_model_.items.begin();
    ApplyModel();
}

void MainWindow::on_btn_find_clicked() {
    deque_model_.iterator = std::find(
        deque_model_.items.begin(),
        deque_model_.items.end(),
        ui->txt_elem_content->text().toStdString()
    );

    ApplyIterator();
}

void MainWindow::on_btn_count_clicked() {
    const int count = static_cast<int>(std::count(
        deque_model_.items.begin(),
        deque_model_.items.end(),
        ui->le_count->text().toStdString()
    ));

    ui->lbl_count->setText(QString::number(count));
}

void MainWindow::on_btn_min_element_clicked() {
    deque_model_.iterator = std::min_element(
        deque_model_.items.begin(),
        deque_model_.items.end()
    );

    ApplyIterator();
}

void MainWindow::on_btn_max_element_clicked() {
    deque_model_.iterator = std::max_element(
        deque_model_.items.begin(),
        deque_model_.items.end()
    );

    ApplyIterator();
}

void MainWindow::on_btn_sort_clicked() {
    deque_model_.items = MergeSort(
        deque_model_.items,
        [](const std::string& lhs, const std::string& rhs) {
            return lhs < rhs;
        }
    );
    deque_model_.iterator = deque_model_.items.begin();
    ApplyModel();
}

void MainWindow::on_btn_sOrT_clicked() {
    deque_model_.items = MergeSort(deque_model_.items, CaseInsensitiveLess);
    deque_model_.iterator = deque_model_.items.begin();
    ApplyModel();
}

void MainWindow::on_btn_shuffle_clicked() {
    std::shuffle(deque_model_.items.begin(), deque_model_.items.end(), m_random_gen_);
    ApplyModel();
}

void MainWindow::on_btn_unique_clicked() {
    if (!std::is_sorted(deque_model_.items.begin(), deque_model_.items.end())) {
        ApplyIterator();
        return;
    }

    const auto new_end = std::unique(deque_model_.items.begin(), deque_model_.items.end());
    deque_model_.items.erase(new_end, deque_model_.items.end());
    deque_model_.iterator = deque_model_.items.begin();
    ApplyModel();
}

void MainWindow::on_btn_reverse_clicked() {
    std::reverse(deque_model_.items.begin(), deque_model_.items.end());
    ApplyModel();
}

void MainWindow::on_btn_lower_bound_clicked() { if (!std::is_sorted(deque_model_.items.begin(), deque_model_.items.end())) {
        return;
    }

    deque_model_.iterator = std::lower_bound(
        deque_model_.items.begin(),
        deque_model_.items.end(),
        ui->txt_elem_content->text().toStdString()
    );

    ApplyIterator();
}

void MainWindow::on_btn_upper_bound_clicked() {
    if (!std::is_sorted(deque_model_.items.begin(), deque_model_.items.end())) {
        return;
    }

    deque_model_.iterator = std::upper_bound(
        deque_model_.items.begin(),
        deque_model_.items.end(),
        ui->txt_elem_content->text().toStdString()
    );

    ApplyIterator();
}