/**
 * Copyright (c) 2025 Dominic Masters
 * 
 * This software is released under the MIT License.
 * https://opensource.org/licenses/MIT
 */

#pragma once
#include "dusk.h"
#include "display/color.h"

#define CAMERA_COUNT_MAX 4

typedef enum {
  CAMERA_PROJECTION_TYPE_PERSPECTIVE,
  CAMERA_PROJECTION_TYPE_PERSPECTIVE_FLIPPED,
  CAMERA_PROJECTION_TYPE_ORTHOGRAPHIC
} cameraprojectiontype_t;

typedef enum {
  CAMERA_VIEW_TYPE_MATRIX,
  CAMERA_VIEW_TYPE_LOOKAT,
  CAMERA_VIEW_TYPE_2D,
  CAMERA_VIEW_TYPE_LOOKAT_PIXEL_PERFECT
} cameraviewtype_t;

typedef struct {
  cameraprojectiontype_t projType;
  cameraviewtype_t viewType;

  union {
    mat4 view;

    struct {
      float_t position[3];
      float_t target[3];
      float_t up[3];
    } lookat;

    struct {
      float_t offset[3];
      float_t target[3];
      float_t up[3];
      float_t pixelsPerUnit;
    } lookatPixelPerfect;

    struct {
      float_t position[2];
      float_t zoom;
    } _2d;
  };

  union {
    struct {
      float_t fov;
    } perspective;

    struct {
      float_t left;
      float_t right;
      float_t top;
      float_t bottom;
    } orthographic;
  };
  
  float_t nearClip;
  float_t farClip;
} camera_t;

/**
 * Initializes a camera to default values. This calls cameraInitPerspective.
 */
void cameraInit(camera_t *camera);

/**
 * Initializes a camera for perspective projection.
 */
void cameraInitPerspective(camera_t *camera);

/**
 * Initializes a camera for orthographic projection.
 */
void cameraInitOrthographic(camera_t *camera);

/**
 * Pushes the camera's view matrix onto the matrix stack.
 * 
 * @param id The ID of the camera entity to use.
 */
void cameraPushMatrix(camera_t* camera);

/**
 * Pops the camera's view matrix off the matrix stack.
 */
void cameraPopMatrix(void);