#include "ui/Application.hpp"

#include <raylib.h>

#include <algorithm>
#include <array>
#include <cstddef>
#include <cstdio>
#include <string>

#include "core/Constants.hpp"
#include "editor/Tool.hpp"
#include "ui/Theme.hpp"

namespace tahgibu {
namespace {

constexpr int kInitialWidth = 1280;
constexpr int kInitialHeight = 800;
constexpr int kMinWidth = 1000;
constexpr int kMinHeight = 640;
constexpr int kUiTargetFps = 60;  // FPS de la interfaz; no tiene relación con los FPS de la animación

constexpr int kFontSize = 16;
constexpr int kSmallFontSize = 14;
constexpr int kButtonPadding = 10;
constexpr float kButtonGap = 4.0f;
constexpr float kPanelHeaderHeight = 24.0f;

constexpr std::array<const char*, 7> kMenus = {
    "Archivo", "Editar", "Animación", "Sprite", "Audio", "Ver", "Lua"};

int px(float value) {
    return static_cast<int>(value);
}

void drawTextVCentered(const char* text, float x, const Rectangle& area, int size, Color color) {
    DrawText(text, px(x), px(area.y + (area.height - static_cast<float>(size)) / 2.0f), size, color);
}

void drawPanelHeader(const Rectangle& panel, const char* title) {
    DrawRectangle(px(panel.x), px(panel.y), px(panel.width), px(kPanelHeaderHeight), theme::kPanelHeader);
    DrawText(title, px(panel.x + 12.0f), px(panel.y + 4.0f), kFontSize, theme::kText);
}

std::array<Rectangle, kToolCount> computeToolButtons(const Rectangle& bar) {
    std::array<Rectangle, kToolCount> rects{};
    float x = bar.x + 8.0f;
    for (std::size_t i = 0; i < kToolCount; ++i) {
        const float w = static_cast<float>(MeasureText(kToolInfos[i].label, kFontSize) + 2 * kButtonPadding);
        rects[i] = {x, bar.y + 6.0f, w, bar.height - 12.0f};
        x += w + kButtonGap;
    }
    return rects;
}

std::array<Rectangle, kMenus.size()> computeMenuRects(const Rectangle& bar) {
    std::array<Rectangle, kMenus.size()> rects{};
    float x = bar.x + 6.0f;
    for (std::size_t i = 0; i < kMenus.size(); ++i) {
        const float w = static_cast<float>(MeasureText(kMenus[i], kFontSize) + 2 * kButtonPadding);
        rects[i] = {x, bar.y + 2.0f, w, bar.height - 4.0f};
        x += w + 2.0f;
    }
    return rects;
}

}  // namespace

Application::Application() {
    SetConfigFlags(FLAG_WINDOW_RESIZABLE);
    const std::string title = std::string(kAppName) + " " + kAppVersion;
    InitWindow(kInitialWidth, kInitialHeight, title.c_str());
    if (!IsWindowReady()) {
        return;
    }
    SetWindowMinSize(kMinWidth, kMinHeight);
    SetExitKey(KEY_NULL);  // Esc no debe cerrar el editor
    SetTargetFPS(kUiTargetFps);
    layout_ = Layout::compute(GetScreenWidth(), GetScreenHeight());
}

Application::~Application() {
    if (IsWindowReady()) {
        CloseWindow();
    }
}

int Application::run() {
    if (!IsWindowReady()) {
        std::fprintf(stderr, "No se pudo crear la ventana (¿hay entorno gráfico y OpenGL disponible?).\n");
        return 1;
    }
    while (!WindowShouldClose()) {
        update();
        draw();
    }
    return 0;
}

void Application::update() {
    layout_ = Layout::compute(GetScreenWidth(), GetScreenHeight());

    if (IsMouseButtonPressed(MOUSE_BUTTON_LEFT)) {
        const Vector2 mouse = GetMousePosition();
        const auto rects = computeToolButtons(layout_.toolBar);
        for (std::size_t i = 0; i < kToolCount; ++i) {
            if (CheckCollisionPointRec(mouse, rects[i])) {
                state_.activeTool = kToolInfos[i].id;
                break;
            }
        }
    }
}

void Application::draw() const {
    BeginDrawing();
    ClearBackground(theme::kWindowBg);
    drawCanvas();
    drawProperties();
    drawTimeline();
    drawToolBar();
    drawMenuBar();
    EndDrawing();
}

void Application::drawMenuBar() const {
    const Rectangle& bar = layout_.menuBar;
    DrawRectangleRec(bar, theme::kPanelHeader);

    const Vector2 mouse = GetMousePosition();
    const auto rects = computeMenuRects(bar);
    for (std::size_t i = 0; i < kMenus.size(); ++i) {
        if (CheckCollisionPointRec(mouse, rects[i])) {
            DrawRectangleRec(rects[i], theme::kHover);
        }
        drawTextVCentered(kMenus[i], rects[i].x + static_cast<float>(kButtonPadding), rects[i], kFontSize,
                          theme::kText);
    }
}

void Application::drawToolBar() const {
    const Rectangle& bar = layout_.toolBar;
    DrawRectangleRec(bar, theme::kPanelBg);
    DrawRectangle(px(bar.x), px(bar.y + bar.height - 1.0f), px(bar.width), 1, theme::kBorder);

    const Vector2 mouse = GetMousePosition();
    const auto rects = computeToolButtons(bar);
    for (std::size_t i = 0; i < kToolCount; ++i) {
        const bool active = state_.activeTool == kToolInfos[i].id;
        const bool hover = CheckCollisionPointRec(mouse, rects[i]);
        const Color background = active ? theme::kAccent : (hover ? theme::kHover : theme::kPanelHeader);
        DrawRectangleRec(rects[i], background);
        drawTextVCentered(kToolInfos[i].label, rects[i].x + static_cast<float>(kButtonPadding), rects[i],
                          kFontSize, active ? theme::kWindowBg : theme::kText);
    }
}

void Application::drawCanvas() const {
    const Rectangle& area = layout_.canvas;
    DrawRectangleRec(area, theme::kCanvasBg);

    // Escenario del tamaño del proyecto, ajustado al área disponible.
    constexpr float kMargin = 32.0f;
    const float projectW = static_cast<float>(project_.width());
    const float projectH = static_cast<float>(project_.height());
    const float availableW = std::max(1.0f, area.width - 2.0f * kMargin);
    const float availableH = std::max(1.0f, area.height - 2.0f * kMargin);
    const float scale = std::min(availableW / projectW, availableH / projectH);
    const float w = projectW * scale;
    const float h = projectH * scale;
    const Rectangle stage{area.x + (area.width - w) / 2.0f, area.y + (area.height - h) / 2.0f, w, h};

    DrawRectangleRec(stage, theme::kStage);
    DrawRectangleLinesEx(stage, 1.0f, theme::kBorder);

    char caption[96];
    std::snprintf(caption, sizeof caption, "Escenario %d x %d", project_.width(), project_.height());
    DrawText(caption, px(area.x + 10.0f), px(area.y + 8.0f), kSmallFontSize, theme::kTextDim);
}

void Application::drawProperties() const {
    const Rectangle& panel = layout_.properties;
    DrawRectangleRec(panel, theme::kPanelBg);
    drawPanelHeader(panel, "Propiedades");
    DrawRectangle(px(panel.x), px(panel.y), 1, px(panel.height), theme::kBorder);

    const std::size_t index = std::min(state_.currentFrame, project_.frameCount() - 1);
    const Frame& frame = project_.frame(index);

    float y = panel.y + kPanelHeaderHeight + 12.0f;
    const float x = panel.x + 12.0f;
    char line[128];
    auto put = [&](Color color) {
        DrawText(line, px(x), px(y), kFontSize, color);
        y += 24.0f;
    };

    std::snprintf(line, sizeof line, "Proyecto: %s", project_.name().c_str());
    put(theme::kText);
    std::snprintf(line, sizeof line, "Resolución: %d x %d", project_.width(), project_.height());
    put(theme::kText);
    std::snprintf(line, sizeof line, "FPS base: %.1f (máx. %.0f)", static_cast<double>(project_.baseFps()),
                  static_cast<double>(kMaxFps));
    put(theme::kText);
    std::snprintf(line, sizeof line, "Frame: %zu / %zu", index + 1, project_.frameCount());
    put(theme::kText);
    std::snprintf(line, sizeof line, "FPS del frame: %.1f %s",
                  static_cast<double>(frame.effectiveFps(project_.baseFps())),
                  frame.hasFpsOverride() ? "(propio)" : "(base)");
    put(theme::kText);
    std::snprintf(line, sizeof line, "Herramienta: %s", toolLabel(state_.activeTool));
    put(theme::kText);

    y += 8.0f;
    std::snprintf(line, sizeof line, "Sprites y vértices: etapas 4 y 8");
    put(theme::kTextDim);
}

void Application::drawTimeline() const {
    const Rectangle& panel = layout_.timeline;
    DrawRectangleRec(panel, theme::kPanelBg);
    drawPanelHeader(panel, "Timeline");
    DrawRectangle(px(panel.x), px(panel.y), px(panel.width), 1, theme::kBorder);

    constexpr std::array<const char*, 3> kTracks = {"Fondo", "Sprite", "Audio"};
    constexpr float kLaneHeight = 32.0f;
    constexpr float kLabelWidth = 90.0f;

    float y = panel.y + kPanelHeaderHeight + 12.0f;
    for (const char* name : kTracks) {
        DrawText(name, px(panel.x + 12.0f), px(y + (kLaneHeight - static_cast<float>(kFontSize)) / 2.0f),
                 kFontSize, theme::kText);
        const Rectangle lane{panel.x + kLabelWidth, y, panel.width - kLabelWidth - 12.0f, kLaneHeight - 4.0f};
        DrawRectangleRec(lane, theme::kPanelHeader);
        y += kLaneHeight;
    }
    DrawText("La timeline se implementa en la etapa 3", px(panel.x + 12.0f), px(y + 8.0f), kSmallFontSize,
             theme::kTextDim);
}

}  // namespace tahgibu