IMX6U-Game/src/Apps/LightGame/src/engine/GameStateManager.cpp

#include "GameStateManager.h"
#include "DrawContext.h"
#include "BitmapFont.h"
#include "ButtonInput.h"
#include "IKeyboardState.h"
#include <cstdio>

namespace LightGame
{
	GameStateManager::GameStateManager()
		: state_(GameState::Title),
		  hud_(),
		  title_blink_ms_(0),
		  title_show_prompt_(true),
		  esc_was_down_(false)
	{
	}

	void GameStateManager::update(GameState current_state, const Platform::IButtonInput* button, const Platform::IKeyboardState* keyboard, uint32_t dt_ms)
	{
		state_ = current_state;

		const bool esc_down = keyboard && keyboard->is_key_down(Platform::KEY_ESC);
		const bool esc_pressed = esc_down && !esc_was_down_;
		esc_was_down_ = esc_down;

		switch (state_)
		{
		case GameState::Title:
			title_blink_ms_ += dt_ms;
			if (title_blink_ms_ >= 500)
			{
				title_blink_ms_ -= 500;
				title_show_prompt_ = !title_show_prompt_;
			}
			break;

		case GameState::Playing:
			if (esc_pressed || (button && button->was_pressed()))
			{
				state_ = GameState::Paused;
			}
			break;

		case GameState::Paused:
			if (esc_pressed || (button && button->was_pressed()))
			{
				state_ = GameState::Playing;
			}
			break;

		case GameState::GameOver:
		case GameState::LevelComplete:
			break;
		}
	}

	void GameStateManager::draw(Core::DrawContext& ctx, const RenderData::BitmapFont& font,
								int32_t screen_w, int32_t screen_h)
	{
		switch (state_)
		{
		case GameState::Title:
			draw_title(ctx, font, screen_w, screen_h);
			break;
		case GameState::Playing:
			draw_hud(ctx, font, screen_w, screen_h);
			break;
		case GameState::Paused:
			draw_hud(ctx, font, screen_w, screen_h);
			draw_pause(ctx, font, screen_w, screen_h);
			break;
		case GameState::GameOver:
			draw_game_over(ctx, font, screen_w, screen_h);
			break;
		case GameState::LevelComplete:
			draw_level_complete(ctx, font, screen_w, screen_h);
			break;
		}
	}

	void GameStateManager::draw_title(Core::DrawContext& ctx, const RenderData::BitmapFont& font,
									  int32_t w, int32_t h)
	{
		ctx.fill_rect(0, 0, w, h, RenderData::Color(0, 0, 40, 255));

		const char* title = "LIGHT QUEST";
		const int32_t title_x = (w - 11 * 8) / 2;
		const int32_t title_y = h / 3;
		ctx.draw_text(font, title_x, title_y, RenderData::Color(255, 255, 100, 255), title);

		if (title_show_prompt_)
		{
			const char* prompt = "PRESS TO START";
			const int32_t prompt_x = (w - 14 * 8) / 2;
			ctx.draw_text(font, prompt_x, title_y + 40, RenderData::Color::White(), prompt);
		}
	}

	void GameStateManager::draw_hud(Core::DrawContext& ctx, const RenderData::BitmapFont& font,
									int32_t w, int32_t)
	{
		draw_light_bar(ctx, 8, 8, 80, 8, hud_.light_level, hud_.light_max);

		char buf[32];
		snprintf(buf, sizeof(buf), "LV%d", hud_.current_level);
		ctx.draw_text(font, w - 48, 8, RenderData::Color::White(), buf);

		snprintf(buf, sizeof(buf), "x%d", hud_.collectibles);
		ctx.draw_text(font, 8, 24, RenderData::Color(255, 255, 0, 255), buf);

		for (int32_t i = 0; i < hud_.lives; ++i)
		{
			ctx.fill_rect(8 + i * 12, 40, 8, 8, RenderData::Color::Red());
		}
	}

	void GameStateManager::draw_pause(Core::DrawContext& ctx, const RenderData::BitmapFont& font,
									  int32_t w, int32_t h)
	{
		ctx.fill_rect(w / 4, h / 3, w / 2, h / 3, RenderData::Color(0, 0, 0, 200));

		const char* text = "PAUSED";
		const int32_t tx = (w - 6 * 8) / 2;
		const int32_t ty = h / 2 - 4;
		ctx.draw_text(font, tx, ty, RenderData::Color::White(), text);
	}

	void GameStateManager::draw_game_over(Core::DrawContext& ctx, const RenderData::BitmapFont& font,
										  int32_t w, int32_t h)
	{
		ctx.fill_rect(0, 0, w, h, RenderData::Color(40, 0, 0, 255));

		const char* text = "GAME OVER";
		const int32_t tx = (w - 9 * 8) / 2;
		const int32_t ty = h / 2 - 4;
		ctx.draw_text(font, tx, ty, RenderData::Color::Red(), text);

		const char* retry = "PRESS TO RETRY";
		const int32_t rx = (w - 14 * 8) / 2;
		ctx.draw_text(font, rx, ty + 24, RenderData::Color::White(), retry);
	}

	void GameStateManager::draw_level_complete(Core::DrawContext& ctx, const RenderData::BitmapFont& font,
											   int32_t w, int32_t h)
	{
		ctx.fill_rect(0, 0, w, h, RenderData::Color(0, 40, 0, 255));

		const char* text = "LEVEL CLEAR!";
		const int32_t tx = (w - 12 * 8) / 2;
		const int32_t ty = h / 2 - 4;
		ctx.draw_text(font, tx, ty, RenderData::Color(100, 255, 100, 255), text);

		char buf[32];
		snprintf(buf, sizeof(buf), "SCORE: %d", hud_.collectibles);
		const int32_t sx = (w - 10 * 8) / 2;
		ctx.draw_text(font, sx, ty + 24, RenderData::Color::White(), buf);
	}

	void GameStateManager::draw_light_bar(Core::DrawContext& ctx, int32_t x, int32_t y,
										  int32_t w, int32_t h, uint16_t level, uint16_t max_level)
	{
		ctx.fill_rect(x, y, w, h, RenderData::Color(60, 60, 60, 255));

		const int32_t fill_w = (max_level > 0) ? (static_cast<int32_t>(level) * (w - 2)) / max_level : 0;
		if (fill_w > 0)
		{
			const uint8_t r = static_cast<uint8_t>(255 * (max_level - level) / max_level);
			const uint8_t g = static_cast<uint8_t>(255 * level / max_level);
			ctx.fill_rect(x + 1, y + 1, fill_w, h - 2, RenderData::Color(r, g, 0, 255));
		}
	}
}