#include "MainWindow.h"

#include <map>
#include <set>

#include <QApplication>
#include <QCloseEvent>
#include <QFile>
#include <QHBoxLayout>
#include <QMessageBox>
#include <QPushButton>
#include <QResizeEvent>
#include <QVBoxLayout>

#include "BlueprintPanel.h"
#include "BuildButtonGrid.h"
#include "BuildingBlocksChangedEvent.h"
#include "BuildingSystem.h"
#include "ConfigLoader.h"
#include "GameWorldView.h"
#include "SchematicChoiceDialog.h"
#include "HeaderBar.h"
#include "SelectedBuildingPanel.h"
#include "ShipLayoutBlueprintSerializer.h"
#include "ShipLayoutDialog.h"
#include "Simulation.h"
#include "Tick.h"
#include "VisualsLoader.h"

MainWindow::MainWindow(Simulation* sim, const std::string& configDir, QWidget* parent)
    : QWidget(parent)
    , m_configDir(configDir)
    , m_visuals(VisualsLoader::load(configDir + "/visuals.toml"))
    , m_sim(sim)
{
    setWindowTitle(tr("Dota Factory"));
    resize(1280, 768);

    m_headerBar = new HeaderBar(this);

    m_gameWorldView = new GameWorldView(sim, &sim->config(), &m_visuals, this);

    m_bottomPanel = new QWidget(this);
    QHBoxLayout* bottomLayout = new QHBoxLayout(m_bottomPanel);
    bottomLayout->setContentsMargins(0, 0, 0, 0);
    bottomLayout->setSpacing(0);

    m_selectedBuildingPanel = new SelectedBuildingPanel(sim, &sim->config(), m_bottomPanel);
    m_buildButtonGrid       = new BuildButtonGrid(&sim->config(), m_bottomPanel);
    m_blueprintPanel        = new BlueprintPanel(sim, &sim->config(), m_bottomPanel);

    bottomLayout->addWidget(m_selectedBuildingPanel, 1);
    bottomLayout->addWidget(m_buildButtonGrid,       1);
    bottomLayout->addWidget(m_blueprintPanel,        1);

    // Signals: game world → other panels
    connect(m_gameWorldView, &GameWorldView::selectionChanged,
            m_selectedBuildingPanel, &SelectedBuildingPanel::onSelectionChanged);

    connect(m_gameWorldView, &GameWorldView::gameOver,
            this, &MainWindow::onGameOver);

    connect(m_gameWorldView, &GameWorldView::escapeMenuRequested,
            this, &MainWindow::onEscapeMenuRequested);

    connect(m_selectedBuildingPanel, &SelectedBuildingPanel::layoutDialogRequested,
            this, &MainWindow::onLayoutDialogRequested);

    // Signals: build grid → game world
    connect(m_buildButtonGrid, &BuildButtonGrid::buildingTypeSelected,
            m_gameWorldView, &GameWorldView::enterBuilderMode);

    connect(m_buildButtonGrid, &BuildButtonGrid::builderModeExited,
            m_gameWorldView, &GameWorldView::exitBuilderMode);

    connect(m_gameWorldView, &GameWorldView::builderModeExited,
            m_buildButtonGrid, &BuildButtonGrid::clearActiveButton);

    connect(m_buildButtonGrid, &BuildButtonGrid::demolishModeToggleRequested,
            m_gameWorldView, &GameWorldView::toggleDemolishMode);

    connect(m_gameWorldView, &GameWorldView::demolishModeChanged,
            m_buildButtonGrid, &BuildButtonGrid::setDemolishModeActive);

    // Signals: blueprint panel ↔ game world
    connect(m_gameWorldView, &GameWorldView::selectionChanged,
            m_blueprintPanel, &BlueprintPanel::onSelectionChanged);

    connect(m_blueprintPanel, &BlueprintPanel::blueprintPlacementRequested,
            m_gameWorldView, &GameWorldView::enterBlueprintMode);

    connect(m_blueprintPanel, &BlueprintPanel::exitBlueprintModeRequested,
            m_gameWorldView, &GameWorldView::exitBlueprintMode);

    connect(m_gameWorldView, &GameWorldView::blueprintModeExited,
            m_blueprintPanel, &BlueprintPanel::clearActiveBlueprintButton);

    // Signals: header bar → game world
    connect(m_headerBar, &HeaderBar::speedChanged,
            m_gameWorldView, &GameWorldView::setGameSpeed);

    m_gameWorldView->setFocus();

    connect(qApp, &QApplication::focusChanged, this, [this](QWidget*, QWidget* newWidget) {
        if (newWidget && newWidget != m_gameWorldView && !QApplication::activeModalWidget())
        {
            m_gameWorldView->setFocus();
        }
    });

    // Load layout blueprints from disk. Missing file is silently ignored.
    const QString bpPath = QCoreApplication::applicationDirPath() + "/ship_layouts.toml";
    QFile bpFile(bpPath);
    if (bpFile.open(QIODevice::ReadOnly | QIODevice::Text))
    {
        try
        {
            m_layoutBlueprints = ShipLayoutBlueprintSerializer::deserialize(
                bpFile.readAll().toStdString());
        }
        catch (const std::exception& e)
        {
            QMessageBox::critical(this, tr("Load Error"),
                tr("Failed to load ship_layouts.toml:\n%1").arg(e.what()));
            m_layoutBlueprints.clear();
        }
    }

    registerForEvents();
}

MainWindow::~MainWindow()
{
    unregisterForEvents();
}

void MainWindow::resizeEvent(QResizeEvent* event)
{
    QWidget::resizeEvent(event);
    layoutPanels();
}

void MainWindow::closeEvent(QCloseEvent* event)
{
    const QString path = QCoreApplication::applicationDirPath() + "/ship_layouts.toml";
    QFile file(path);
    if (file.open(QIODevice::WriteOnly | QIODevice::Text))
    {
        try
        {
            const std::string content =
                ShipLayoutBlueprintSerializer::serialize(m_layoutBlueprints);
            file.write(QByteArray::fromStdString(content));
        }
        catch (...) {}
    }
    QWidget::closeEvent(event);
}

void MainWindow::layoutPanels()
{
    const int totalW  = width();
    const int totalH  = height();
    const int headerH = m_headerBar->sizeHint().height();
    if (headerH <= 0) { return; }
    const int remaining = totalH - headerH;
    const int gameH     = remaining * 70 / 100;
    const int panelH    = remaining - gameH;

    m_headerBar->setGeometry(0, 0, totalW, headerH);
    m_gameWorldView->setGeometry(0, headerH, totalW, gameH);
    m_bottomPanel->setGeometry(0, headerH + gameH, totalW, panelH);
}

void MainWindow::handleEvent(std::shared_ptr<const BuildingBlocksChangedEvent> event)
{
    m_buildButtonGrid->updateAffordability(event->blocks);
}

void MainWindow::handleEvent(std::shared_ptr<const SchematicChoicesAvailableEvent> event)
{
    const double prevSpeed = m_gameWorldView->gameSpeed();
    m_gameWorldView->setGameSpeed(0.0);

    SchematicChoiceDialog dialog(event->choices, this);
    dialog.exec();

    m_sim->applySchematicChoice(dialog.getChosenIndex());

    m_gameWorldView->setGameSpeed(prevSpeed);
}

void MainWindow::onEscapeMenuRequested()
{
    const double prevSpeed = m_gameWorldView->gameSpeed();
    m_gameWorldView->setGameSpeed(0.0);

    QMessageBox box(this);
    box.setWindowTitle(tr("Paused"));
    QPushButton* continueBtn = box.addButton(tr("Continue"), QMessageBox::AcceptRole);
    QPushButton* restartBtn  = box.addButton(tr("Restart"),  QMessageBox::ResetRole);
    QPushButton* quitBtn     = box.addButton(tr("Quit"),     QMessageBox::DestructiveRole);
    box.setEscapeButton(continueBtn);
    box.exec();

    QAbstractButton* clicked = box.clickedButton();
    if (clicked == restartBtn)
    {
        try
        {
            GameConfig newConfig = ConfigLoader::loadFromDirectory(m_configDir);
            VisualsConfig newVisuals = VisualsLoader::load(m_configDir + "/visuals.toml");
            m_visuals = std::move(newVisuals);
            m_sim->reset(std::move(newConfig));
        }
        catch (const std::exception& e)
        {
            QMessageBox::critical(this, tr("Config Error"),
                tr("Failed to reload config:\n%1").arg(e.what()));
            m_gameWorldView->setGameSpeed(prevSpeed);
            return;
        }
        m_gameWorldView->resetForNewGame();
    }
    else if (clicked == quitBtn)
    {
        close();
    }
    else
    {
        m_gameWorldView->setGameSpeed(prevSpeed);
    }
}

void MainWindow::onLayoutDialogRequested(BuildingId shipyardId)
{
    const double prevSpeed = m_gameWorldView->gameSpeed();
    m_gameWorldView->setGameSpeed(0.0);

    const Building* b = m_sim->buildings().findBuilding(shipyardId);
    if (!b)
    {
        m_gameWorldView->setGameSpeed(prevSpeed);
        return;
    }

    ShipLayoutConfig currentLayout;
    if (b->shipLayout.has_value())
    {
        currentLayout = *b->shipLayout;
    }

    std::set<std::string> unlockedModuleIds;
    std::map<std::string, int> moduleLevels;
    for (const ModuleDef& def : m_sim->config().modules.modules)
    {
        if (m_sim->isModuleSchematicUnlocked(def.id))
        {
            unlockedModuleIds.insert(def.id);
        }
        moduleLevels[def.id] = m_sim->moduleSchematicLevel(def.id);
    }

    ShipLayoutDialog dialog(&m_sim->config(), b->recipeId, currentLayout,
                            m_layoutBlueprints,
                            std::move(unlockedModuleIds),
                            std::move(moduleLevels),
                            this);
    if (dialog.exec() == QDialog::Accepted && dialog.result().has_value())
    {
        m_sim->buildings().setShipLayout(shipyardId, *dialog.result());
    }

    m_gameWorldView->setGameSpeed(prevSpeed);
}

void MainWindow::onGameOver()
{
    const Tick tick = m_sim->currentTick();
    const int totalSeconds = static_cast<int>(ticksToSeconds(tick));
    const int minutes = totalSeconds / 60;
    const int seconds = totalSeconds % 60;

    QMessageBox box(this);
    box.setWindowTitle(tr("Game Over"));
    box.setText(tr("HQ destroyed!\nSurvival time: %1:%2")
        .arg(minutes, 2, 10, QChar('0'))
        .arg(seconds, 2, 10, QChar('0')));
    QPushButton* restartBtn = box.addButton(tr("Restart"), QMessageBox::AcceptRole);
    box.addButton(tr("Quit"), QMessageBox::RejectRole);
    box.exec();

    if (box.clickedButton() == restartBtn)
    {
        try
        {
            GameConfig newConfig = ConfigLoader::loadFromDirectory(m_configDir);
            VisualsConfig newVisuals = VisualsLoader::load(m_configDir + "/visuals.toml");
            m_visuals = std::move(newVisuals);
            m_sim->reset(std::move(newConfig));
        }
        catch (const std::exception& e)
        {
            QMessageBox::critical(this, tr("Config Error"),
                tr("Failed to reload config:\n%1").arg(e.what()));
            return;
        }
        m_gameWorldView->resetForNewGame();
    }
    else
    {
        close();
    }
}