#include <stdlib.h>
#include <stdio.h>
#include <GLFW/glfw3.h>
#include "rendlib.h"
#include "camera.h"
#include "object.h"

#define INPUT_ESCAPE    0b00000001
#define INPUT_RELOAD    0b00000010
#define INPUT_LEFT      0b00000100
#define INPUT_RIGHT     0b00001000
#define INPUT_DOWN      0b00010000
#define INPUT_UP        0b00100000

#define MOVEMENT_SPEED  0.2f

char input = 0;

void keyboardp(int key, int scancode, int action, int mods) {
    if (action == GLFW_PRESS) {
        switch (key) {
            case GLFW_KEY_Q: 
            case GLFW_KEY_ESCAPE: 
                input |= INPUT_ESCAPE; 
                break;
            case GLFW_KEY_R: 
                input |= INPUT_RELOAD;
                break;
            case GLFW_KEY_A:
            case GLFW_KEY_LEFT:
                input |= INPUT_LEFT;
                break;
            case GLFW_KEY_D:
            case GLFW_KEY_RIGHT:
                input |= INPUT_RIGHT;
                break;
            case GLFW_KEY_S:
            case GLFW_KEY_DOWN:
                input |= INPUT_DOWN;
                break;
            case GLFW_KEY_W:
            case GLFW_KEY_UP:
                input |= INPUT_UP;
                break;
        }
    } else if (action == GLFW_RELEASE) {
        switch (key) {
            case GLFW_KEY_A:
            case GLFW_KEY_LEFT:
                input &= ~INPUT_LEFT;
                break;
            case GLFW_KEY_D:
            case GLFW_KEY_RIGHT:
                input &= ~INPUT_RIGHT;
                break;
            case GLFW_KEY_S:
            case GLFW_KEY_DOWN:
                input &= ~INPUT_DOWN;
                break;
            case GLFW_KEY_W:
            case GLFW_KEY_UP:
                input &= ~INPUT_UP;
                break;
        }
    }
}

int warped_pointer = 0;
int first_pointer = 1;
void mousep(double x, double y) {
    GLint screen_viewport[4];
    if (warped_pointer == 1) {
        warped_pointer = 0;
        return;
    }

    warped_pointer = 1;
    glGetIntegerv(GL_VIEWPORT, screen_viewport);
    GLFWwindow *w = glfwGetCurrentContext();
    glfwSetCursorPos(w, (screen_viewport[2]/2), (screen_viewport[3]/2));

    if (first_pointer == 1) {
        first_pointer = 0;
        return;
    }

    float offset_x = (float) (x - (screen_viewport[2]/2)) * ac->sensitivity;
    float offset_y = (float) (y - (screen_viewport[3]/2)) * ac->sensitivity;

    ac->yaw += offset_x;
    ac->pitch -= offset_y;

    if (ac->pitch < -89.9f) {
        ac->pitch = -89.9f;
    }
    if (ac->pitch > 89.9f) {
        ac->pitch = 89.9f;
    }

    vec3 view_direction = { cos(glm_rad(ac->yaw)) * cos(glm_rad(ac->pitch)),
	sin(glm_rad(ac->pitch)),
	sin(glm_rad(ac->yaw)) * cos(glm_rad(ac->pitch))
    };
    glm_normalize_to(view_direction, ac->front);
}

void periodic_input(void) {
    int ret = 0;
    if (input & INPUT_ESCAPE) {
        exit(EXIT_SUCCESS);
        input &= ~INPUT_ESCAPE;
    }
    
    if (input & INPUT_LEFT) {
        vec3 side_scalar = {MOVEMENT_SPEED, MOVEMENT_SPEED,  MOVEMENT_SPEED};
        vec3 camera_side;
        glm_cross(ac->front, ac->up, camera_side);
        glm_normalize(camera_side);
        glm_vec3_mul(camera_side, side_scalar, camera_side);
        glm_vec3_sub(ac->pos, camera_side, ac->pos);
    }

    if (input & INPUT_RIGHT) {
        vec3 side_scalar = {MOVEMENT_SPEED, MOVEMENT_SPEED,  MOVEMENT_SPEED};
        vec3 camera_side;
        glm_cross(ac->front, ac->up, camera_side);
        glm_normalize(camera_side);
        glm_vec3_mul(camera_side, side_scalar, camera_side);
        glm_vec3_add(ac->pos, camera_side, ac->pos);
    }

    if (input & INPUT_DOWN) {
        vec3 front_scalar = {MOVEMENT_SPEED, MOVEMENT_SPEED,  MOVEMENT_SPEED};
        glm_vec3_mul(front_scalar, ac->front, front_scalar);
        glm_vec3_sub(ac->pos, front_scalar, ac->pos);
    }

    if (input & INPUT_UP) {
        vec3 front_scalar = {MOVEMENT_SPEED, MOVEMENT_SPEED,  MOVEMENT_SPEED};
        glm_vec3_mul(front_scalar, ac->front, front_scalar);
        glm_vec3_add(ac->pos, front_scalar, ac->pos);
    }

}

void updatep(void) {
    periodic_input();
}

int main(int argc, char *argv[]) {
    int ret = rendlib_start_window(argc, argv);
    if (ret < 0) {
        fprintf(stderr, "--error: %d\n", ret);
        return EXIT_FAILURE;
    }

    keyboard_probe = &keyboardp;
    mouse_probe = &mousep;
    update_probe = &updatep;

    struct model *m = load_model("assets-01/sphere.obj");
    if (m == NULL) {
        fprintf(stderr, "--error: loading model\n");
        return EXIT_FAILURE;
    }

    struct object *o = create_object(&objects, m);
    if (o == NULL) {
        fprintf(stderr, "--error: creating object\n");
        return EXIT_FAILURE;
    }

    ac = create_camera(CAMERA_PERSPECTIVE);
    if (ac == NULL) {
        fprintf(stderr, "--error: creating camera\n");
        return EXIT_FAILURE;
    }

    ret = rendlib_render();
    if (ret < 0) {
        fprintf(stderr, "--error: %d\n", ret);
        return EXIT_FAILURE;
    }

    fprintf(stdout, "--rendering\n");

    return EXIT_SUCCESS;
}