#include "core/input/global_inputs.hpp"

#include <SDL3/SDL.h>

#include <algorithm>
#include <string>

#include "core/input/key_config.hpp"
#include "core/locale/locale.hpp"
#include "core/rendering/notifier.hpp"
#include "core/rendering/render_info.hpp"
#include "core/rendering/screen.hpp"
#include "core/system/event_buffer.hpp"
#include "game/options.hpp"
#include "utils/defaults.hpp"

namespace GlobalInputs {

    namespace {

        // Finestra per a confirmar l'eixida amb una segona pulsació d'Escape.
        constexpr float EXIT_WINDOW_S = 1.5F;
        constexpr int MIN_ZOOM = 1;
        constexpr int MAX_ZOOM = 6;

        float exit_window_s = 0.0F;
        bool quit_requested = false;

        // Canvia uniforms i shader actiu sense recrear la finestra.
        void reapplyShader() {
            Screen::get().setActiveShader(Options::buildActiveShader());
            Screen::get().applyPostFXParams(Options::buildPostFXParams());
            Screen::get().applyCrtPiParams(Options::buildCrtPiParams());
        }

        void notifyLocale(const std::string& key) {
            Notifier::get().notify(Locale::get().text(key));
        }

        void onDecZoom() {
            if (Options::window.fullscreen) { return; }
            if (Options::window.zoom <= MIN_ZOOM) { return; }
            Options::window.zoom--;
            Screen::get().setWindowZoom(Options::window.zoom);
            Options::saveToFile();
            Notifier::get().notify(Locale::get().text("input.zoom") + " x" + std::to_string(Options::window.zoom));
        }

        void onIncZoom() {
            if (Options::window.fullscreen) { return; }
            if (Options::window.zoom >= MAX_ZOOM) { return; }
            Options::window.zoom++;
            Screen::get().setWindowZoom(Options::window.zoom);
            Options::saveToFile();
            Notifier::get().notify(Locale::get().text("input.zoom") + " x" + std::to_string(Options::window.zoom));
        }

        void onFullscreen() {
            Options::window.fullscreen = !Options::window.fullscreen;
            Screen::get().setFullscreen(Options::window.fullscreen);
            Options::saveToFile();
            notifyLocale(Options::window.fullscreen ? "input.fullscreen_on" : "input.fullscreen_off");
        }

        void onToggleVSync() {
            Options::video.vsync = !Options::video.vsync;
            Screen::get().setVSync(Options::video.vsync);
            Options::saveToFile();
            notifyLocale(Options::video.vsync ? "input.vsync_on" : "input.vsync_off");
        }

        void onToggleShader() {
            Options::video.shader.enabled = !Options::video.shader.enabled;
            reapplyShader();
            Options::saveToFile();
            notifyLocale(Options::video.shader.enabled ? "input.shader_on" : "input.shader_off");
        }

        void onNextShader() {
            Options::video.shader.current_shader = (Options::video.shader.current_shader == "crtpi") ? "postfx" : "crtpi";
            reapplyShader();
            Options::saveToFile();
            Notifier::get().notify(Locale::get().text("input.shader") + ": " + Options::video.shader.current_shader);
        }

        // Busca l'entrada actual al vector de presets i passa a la següent
        // (wrap-around). Si no en troba cap s'evita el canvi silenciosament.
        void onNextPreset() {
            const bool IS_CRTPI = Options::video.shader.current_shader == "crtpi";
            if (IS_CRTPI) {
                if (Options::crtpi_presets.empty()) { return; }
                auto it = std::ranges::find_if(Options::crtpi_presets,
                    [](const auto& preset) { return preset.name == Options::video.shader.current_crtpi_preset; });
                std::size_t idx = (it == Options::crtpi_presets.end()) ? 0 : std::distance(Options::crtpi_presets.begin(), it);
                idx = (idx + 1) % Options::crtpi_presets.size();
                Options::video.shader.current_crtpi_preset = Options::crtpi_presets[idx].name;
            } else {
                if (Options::postfx_presets.empty()) { return; }
                auto it = std::ranges::find_if(Options::postfx_presets,
                    [](const auto& preset) { return preset.name == Options::video.shader.current_postfx_preset; });
                std::size_t idx = (it == Options::postfx_presets.end()) ? 0 : std::distance(Options::postfx_presets.begin(), it);
                idx = (idx + 1) % Options::postfx_presets.size();
                Options::video.shader.current_postfx_preset = Options::postfx_presets[idx].name;
            }
            reapplyShader();
            Options::saveToFile();
            const std::string& name = IS_CRTPI ? Options::video.shader.current_crtpi_preset : Options::video.shader.current_postfx_preset;
            Notifier::get().notify(Locale::get().text("input.preset") + ": " + name);
        }

        void onNextScalingMode() {
            using Mode = Defaults::ScalingMode;
            Options::video.scaling_mode = static_cast<Mode>((static_cast<int>(Options::video.scaling_mode) + 1) % 5);
            Screen::get().setScalingMode(Options::video.scaling_mode);
            Options::saveToFile();
            const char* mode_key = nullptr;
            switch (Options::video.scaling_mode) {
                case Mode::DISABLED:
                    mode_key = "input.scaling_disabled";
                    break;
                case Mode::STRETCH:
                    mode_key = "input.scaling_stretch";
                    break;
                case Mode::LETTERBOX:
                    mode_key = "input.scaling_letterbox";
                    break;
                case Mode::OVERSCAN:
                    mode_key = "input.scaling_overscan";
                    break;
                case Mode::INTEGER:
                    mode_key = "input.scaling_integer";
                    break;
            }
            notifyLocale(mode_key);
        }

        void onToggleRenderInfo() {
            RenderInfo::get().toggle();
        }

        void onExit() {
            if (exit_window_s > 0.0F) {
                quit_requested = true;
                return;
            }
            exit_window_s = EXIT_WINDOW_S;
            // La notificació dura el doble de la finestra; si l'usuari no
            // prem una segona volta abans del timeout, es desarmarà sol.
            Notifier::get().notify(Locale::get().text("input.press_again_exit"),
                Notification::DEFAULT.text_color,
                Notification::DEFAULT.bg_color,
                static_cast<int>(EXIT_WINDOW_S * 1000.0F));
        }

    }  // namespace

    void update(int delta_ms) {
        exit_window_s = std::max(0.0F, exit_window_s - (static_cast<float>(delta_ms) / 1000.0F));

        for (const auto& event : EventBuffer::events) {
            if (event.type != SDL_EVENT_KEY_DOWN) { continue; }
            const auto SC = event.key.scancode;
            if (SC == KeyConfig::get().scancode("dec_zoom")) {
                onDecZoom();
            } else if (SC == KeyConfig::get().scancode("inc_zoom")) {
                onIncZoom();
            } else if (SC == KeyConfig::get().scancode("fullscreen")) {
                onFullscreen();
            } else if (SC == KeyConfig::get().scancode("toggle_shader")) {
                onToggleShader();
            } else if (SC == KeyConfig::get().scancode("toggle_vsync")) {
                onToggleVSync();
            } else if (SC == KeyConfig::get().scancode("next_shader")) {
                onNextShader();
            } else if (SC == KeyConfig::get().scancode("next_preset")) {
                onNextPreset();
            } else if (SC == KeyConfig::get().scancode("next_scaling_mode")) {
                onNextScalingMode();
            } else if (SC == KeyConfig::get().scancode("toggle_render_info")) {
                onToggleRenderInfo();
            } else if (SC == KeyConfig::get().scancode("exit")) {
                onExit();
            }
        }
    }

    auto wantsQuit() -> bool {
        return quit_requested;
    }

}  // namespace GlobalInputs