#import "keyboard.h"
#import "memory.h"
#import "oops.h"

#include <string.h>

typedef struct {
    void (*action)(game_state *g);
    Uint32 repeat_ticks;
    long long ticks_remaining;
    int activate_anyway; // Hack to support key_down_only and key_up_only.
    int on_key_down_up;

    Uint8 state;
} keybinding;



keybinding *_bindings()
{
    static keybinding *bindings = NULL;
    if (bindings == NULL) {
        bindings = (keybinding *)malloc(sizeof(keybinding) * SDLK_LAST); // SDLK_LAST is the last keysym + 1
        memset(bindings, 0, sizeof(keybinding) * SDLK_LAST);
    }
    return bindings;
}

void keyboard_actions(game_state *g)
{
    static Uint32 last_ticks = 0;
    Uint32 delta_ticks = SDL_GetTicks() - last_ticks;
    int i;
    keybinding *b = _bindings();
    for (i=0; i<SDLK_LAST; i++) {
        if (b[i].action != NULL) {
            if (b[i].state == SDL_PRESSED && b[i].repeat_ticks != 0) {
                b[i].ticks_remaining -= delta_ticks;
                if (b[i].ticks_remaining <= 0) {
                    while (b[i].ticks_remaining <= 0) {
                        Uint32 remainder = b[i].ticks_remaining;
                        b[i].ticks_remaining = b[i].repeat_ticks - remainder;
                    }
                    b[i].action(g);
                }
            } else if (b[i].activate_anyway) {
                b[i].activate_anyway = 0;
                b[i].action(g);
            }
        }
    }
    last_ticks = SDL_GetTicks();
}

void bind_key(SDLKey key, void (*action)(game_state *g), float repeat_interval)
{
    keybinding *bindings = _bindings();
    Uint8 *current_state = SDL_GetKeyState(NULL);
    int onkdu = 0;
    if (repeat_interval == key_down_only) {
        onkdu = 1;
    } else if (repeat_interval == key_up_only) {
        onkdu = -1;
    }
    keybinding new = {action, 1000 * repeat_interval, 0, 0, onkdu, current_state[key]};
    bindings[key] = new;
}

const float key_down_only = -0.0000001;
const float key_up_only = -0.0000002;

void unbind_key(SDLKey key)
{
    keybinding *bindings = _bindings();
    keybinding zero = {NULL, 0};
    bindings[key] = zero;
}

void update_key_state(SDLKey key, Uint8 state)
{
    keybinding *bindings = _bindings();
    bindings[key].state = state;
    bindings[key].ticks_remaining = bindings[key].repeat_ticks;
    if (state == SDL_PRESSED && bindings[key].on_key_down_up == 1) {
        bindings[key].activate_anyway = 1;
    } else if (state == SDL_RELEASED && bindings[key].on_key_down_up == -1) {
        bindings[key].activate_anyway = 1;
    } else {
        bindings[key].activate_anyway = 0;
    }
}