// end_screen.hpp
// Ending screen: 4 images revealed one by one as particle bursts from centre.
// All layers are ALWAYS rendered as particles — no texture overdraw possible.
// Clear color: black. Text is white.

#pragma once

#include <SDL3/SDL.h>
#include <SDL3_image/SDL_image.h>
#include <vector>
#include <array>
#include <random>
#include <cstdint>

struct EndParticle {
    SDL_FPoint origin;   // final screen position (centred)
    SDL_FPoint current;  // animated position
};

class EndScreen {
public:
    bool running = true;

    explicit EndScreen(SDL_Renderer* r);
    ~EndScreen();

    void Update();
    void Render();
    void UpdateScreen();

private:
    enum class LayerState { WAITING, SPREADING_IN, VISIBLE };

    // ── Timings (ms) ─────────────────────────────────────────────────────────
    // Fast burst animation, long delays between words.
    static constexpr Uint64 SPREAD_DURATION_MS = 420;   // fast particle burst
    static constexpr Uint64 GAP_AFTER_0_MS     = 200;   // "to" → "be"   (quick follow-up)
    static constexpr Uint64 GAP_AFTER_1_MS     = 1000;  // "be" → "continued"
    static constexpr Uint64 GAP_AFTER_2_MS     = 2000;  // "continued" → "nope"
    static constexpr Uint64 END_PAUSE_MS       = 2000;  // hold all visible before done

    void Init();
    void BuildParticles(int layer_idx);
    void StartLayer(int idx);
    SDL_FPoint LayerOffset() const;   // same offset for all layers (same image size)
    static float Lerp(float a, float b, float t);

    SDL_Renderer* renderer = nullptr;
    int screen_w = 0, screen_h = 0;

    static constexpr int NUM_LAYERS = 4;

    struct LayerAsset {
        SDL_Surface* surface = nullptr;
        // No texture needed — we render entirely via particles
    };
    std::array<LayerAsset, NUM_LAYERS>               assets{};
    std::array<LayerState, NUM_LAYERS>               layer_state{};
    std::array<Uint64, NUM_LAYERS>                   layer_start_tick{}; // when spreading began
    std::array<Uint64, NUM_LAYERS>                   layer_due{};        // scheduled start tick
    std::array<std::vector<EndParticle>, NUM_LAYERS> layer_particles{};

    bool   end_timer_started = false;
    Uint64 end_timer_start   = 0;
    Uint64 last_time         = 0;

    std::mt19937 rng;
};

namespace EndScreen_Event {
    void event_Loop(SDL_Renderer* renderer);
}