Gizmo_Space :: enum {
    LOCAL;
    WORLD;
}

Transform_Axis :: enum {
    NONE;
    UP;
    FORWARD;
    RIGHT;
    CENTER;
}

Transform_Type :: enum {
    TRANSLATION;
    ROTATION;
    SCALE;
}

Buffer_Info :: struct {
    buffer: Buffer_Handle;
    vertex_count: u32;
}

Transform_Gizmo :: struct {
    active: bool = false;
    transform_type: Transform_Type = .TRANSLATION;
    space: Gizmo_Space;

    selected_axis: Transform_Axis;

    first_hit_position: Vector3;
    actual_entity_position: Vector3; // The actual position of the selected entity. Used for snapping
    actual_entity_scale: Vector3; // The actual position of the selected entity. Used for snapping
    last_circle_dir: Vector3;

    clicked: bool;

    transform: Transform;

    can_use: bool = true;

    center_model_buffer: Buffer_Handle;
    up_model_buffer: Buffer_Handle;
    forward_model_buffer: Buffer_Handle;
    right_model_buffer: Buffer_Handle;

    color_center: Color;
    color_up: Color;
    color_forward: Color;
    color_right: Color;

    color_center_buffer: Buffer_Handle;
    color_up_buffer: Buffer_Handle;
    color_forward_buffer: Buffer_Handle;
    color_right_buffer: Buffer_Handle;

    uniform_gizmo_scale: float;
}

Editor :: struct {
    show_menu: bool;
    should_check_entities: bool;
    camera: Camera;
    transform_gizmo: Transform_Gizmo;
    selected_entities: [..] *Entity;

    mouse_viewport_state: Interaction_State;
    last_right_mouse_click_time: float;

    menu_position: Vector2;
}

init_editor :: () {
    aspect_ratio := cast(float)engine.renderer.render_target_width / cast(float)engine.renderer.render_target_height;
    engine.editor.camera = create_perspective_camera(.{0, 10, -10}, yaw=0, pitch=-40, roll=0.0, fov=40, aspect=aspect_ratio);
}

update_transform_gizmo :: (ray: Ray, mouse_position: Vector2) -> bool {
    return false;
//    selected_entity := engine.editor.selected_entity;
//
//    if key_down(.TAB) {
//        if engine.editor.transform_gizmo.space == {
//            case .WORLD;
//                engine.editor.transform_gizmo.space = .LOCAL;
//            case .LOCAL;
//                engine.editor.transform_gizmo.space = .WORLD;
//        }
//    }
//
//    if engine.editor.transform_gizmo.space == {
//        case .WORLD;
//            set_rotation(*engine.editor.transform_gizmo.transform, .{0,0,0,1});
//        case .LOCAL;
//            set_rotation(*engine.editor.transform_gizmo.transform, selected_entity.transform.orientation);
//    }
//
//    if engine.editor.transform_gizmo.transform_type == {
//        case .TRANSLATION;
//            if !key_pressed(.MOUSE_LEFT) {
//                selected_axis, t := intersect_translation_gizmo(ray);
//                engine.editor.transform_gizmo.selected_axis = selected_axis;
//            } else if engine.editor.transform_gizmo.can_use && engine.editor.transform_gizmo.selected_axis != .NONE {
//                first_update :=  key_down(.MOUSE_LEFT);
//
//                if first_update {
//                    engine.editor.transform_gizmo.actual_entity_position = selected_entity.transform.position;
//                }
//
//                // Move the currently selected entity along the selected axis
//                axis_vec : Vector3;
//
//                if engine.editor.transform_gizmo.selected_axis == {
//                    case .UP;
//                        axis_vec.y = 1;
//                    case .FORWARD;
//                        axis_vec.z = 1;
//                    case .RIGHT;
//                        axis_vec.x = 1;
//                }
//
//                r1 : Ray;
//                r1.origin = selected_entity.transform.position;
//                r1.direction = rotate(axis_vec, engine.editor.transform_gizmo.transform.orientation);
//
//                r2 := normalized_screen_to_ray_v2(*engine.editor.camera, mouse_position);
//
//                d, t1, t2 := closest_distance_between_rays(r1, r2);
//
//                new_position := r1.origin + r1.direction * t1;
//
//                if first_update {
//                    engine.editor.transform_gizmo.first_hit_position = new_position;
//                }
//
//                position_change := new_position - engine.editor.transform_gizmo.first_hit_position;
//
//                entity_position := engine.editor.transform_gizmo.actual_entity_position + position_change;
//
//                if selected_entity.flags & Entity_Flags.SNAP_TO_GRID {
//                    entity_position.x -= fmod_cycling(entity_position.x - selected_entity.snap_offset.x, selected_entity.snap_intervals.x);// + selected_entity.snap_offset.x;
//                    entity_position.y -= fmod_cycling(entity_position.y - selected_entity.snap_offset.y, selected_entity.snap_intervals.y);// + selected_entity.snap_offset.y;
//                    entity_position.z -= fmod_cycling(entity_position.z - selected_entity.snap_offset.z, selected_entity.snap_intervals.z);// + selected_entity.snap_offset.z;
//                }
//
//                selected_entity.transform.position = entity_position;
//                set_position(*engine.editor.transform_gizmo.transform, entity_position);
//            }
//
//            color_up := engine.editor.transform_gizmo.color_up;
//            color_forward := engine.editor.transform_gizmo.color_forward;
//            color_right := engine.editor.transform_gizmo.color_right;
//
//            if engine.editor.transform_gizmo.selected_axis == {
//                case .NONE;
//                case .UP;
//                    color_up = Color.{1,1,0,1};
//                case .FORWARD;
//                    color_forward = Color.{1,1,0,1};
//                case .RIGHT;
//                    color_right = Color.{1,1,0,1};
//            }
//
//            upload_data_to_buffer(engine.renderer, engine.editor.transform_gizmo.color_up_buffer, *color_up, size_of(Color));
//            upload_data_to_buffer(engine.renderer, engine.editor.transform_gizmo.color_forward_buffer, *color_forward, size_of(Color));
//            upload_data_to_buffer(engine.renderer, engine.editor.transform_gizmo.color_right_buffer, *color_right, size_of(Color));
//        case .ROTATION;
//            selected_entity := engine.editor.selected_entity;
//
//            if !engine.editor.transform_gizmo.clicked {
//                selected_axis, point := intersect_rotation_gizmo(ray);
//                engine.editor.transform_gizmo.selected_axis = selected_axis;
//
//                if engine.editor.transform_gizmo.selected_axis != .NONE && key_down(.MOUSE_LEFT) {
//                    engine.editor.transform_gizmo.clicked = true;
//                    engine.editor.transform_gizmo.last_circle_dir = normalize(point - selected_entity.transform.position);
//                }
//            } else if !key_pressed(.MOUSE_LEFT) {
//                engine.editor.transform_gizmo.clicked = false;
//            } else {
//                direction : Vector3;
//                if engine.editor.transform_gizmo.selected_axis == {
//                    case .UP;
//                    direction = .{0,1,0};
//                    case .FORWARD;
//                    direction = .{0,0,1};
//                    case .RIGHT;
//                    direction = .{1,0,0};
//                }
//                direction = rotate(direction, engine.editor.transform_gizmo.transform.orientation);
//
//                // Find the rotation
//                circle : Circle;
//                circle.radius = engine.editor.transform_gizmo.uniform_gizmo_scale;
//                circle.center = selected_entity.transform.position;
//                circle.orientation = direction;
//
//                distance, point := closest_distance_ray_circle(ray, circle);
//                new_dir := normalize(point - selected_entity.transform.position);
//
//                dotp := dot(engine.editor.transform_gizmo.last_circle_dir, new_dir);
//                angle := acos(clamp(dotp, -1.0, 1.0));
//                cp := cross(engine.editor.transform_gizmo.last_circle_dir, new_dir);
//
//                if dot(direction, cp) < 0 {
//                    angle *= -1.0;
//                }
//
//                q : Quaternion;
//                set_from_axis_and_angle(*q, direction, angle);
//
//                selected_entity.transform.orientation = q * selected_entity.transform.orientation;
//                update_matrix(*selected_entity.transform);
//
//                set_rotation(*engine.editor.transform_gizmo.transform, selected_entity.transform.orientation);
//
//                engine.editor.transform_gizmo.last_circle_dir = new_dir;
//            }
//
//            color_up := engine.editor.transform_gizmo.color_up;
//            color_forward := engine.editor.transform_gizmo.color_forward;
//            color_right := engine.editor.transform_gizmo.color_right;
//
//            if engine.editor.transform_gizmo.selected_axis == {
//                case .NONE;
//                case .UP;
//                color_up = Color.{1,1,0,1};
//                case .FORWARD;
//                color_forward = Color.{1,1,0,1};
//                case .RIGHT;
//                color_right = Color.{1,1,0,1};
//            }
//
//            upload_data_to_buffer(engine.renderer, engine.editor.transform_gizmo.color_up_buffer, *color_up, size_of(Color));
//            upload_data_to_buffer(engine.renderer, engine.editor.transform_gizmo.color_forward_buffer, *color_forward, size_of(Color));
//            upload_data_to_buffer(engine.renderer, engine.editor.transform_gizmo.color_right_buffer, *color_right, size_of(Color));
//        case .SCALE;
//            if !key_pressed(.MOUSE_LEFT) {
//                selected_axis, t := intersect_scale_gizmo(ray);
//                engine.editor.transform_gizmo.selected_axis = selected_axis;
//            } else if engine.editor.transform_gizmo.selected_axis != .NONE {
//                selected_entity := engine.editor.selected_entity;
//                first_update :=  key_down(.MOUSE_LEFT);
//
//                if first_update {
//                    engine.editor.transform_gizmo.actual_entity_position = selected_entity.transform.position;
//                    engine.editor.transform_gizmo.actual_entity_scale = selected_entity.transform.scale;
//                }
//
//                // Move the currently selected entity along the selected axis
//                axis_vec : Vector3;
//
//                if engine.editor.transform_gizmo.selected_axis == {
//                    case .UP;
//                    axis_vec.y = 1;
//                    case .FORWARD;
//                    axis_vec.z = -1;
//                    case .RIGHT;
//                    axis_vec.x = 1;
//                    case .CENTER; axis_vec = .{1,1,1};
//                }
//
//                r1 : Ray;
//                r1.origin = selected_entity.transform.position;
//                r1.direction = rotate(axis_vec, engine.editor.transform_gizmo.transform.orientation);
//                // Shoot a ray from screen to world
//                mouse_position : Vector2;
//                mouse_position.x = xx engine.engine.input.mouse.x;
//                mouse_position.y = xx engine.engine.input.mouse.y;
//
//                screen_size : Vector2;
//                screen_size.x = cast(float)engine.engine.window.width;
//                screen_size.y = cast(float)engine.engine.window.height;
//
//                r2 := screen_to_ray_v2(*engine.editor.camera, mouse_position, screen_size);
//
//                d, t1, t2 := closest_distance_between_rays(r1, r2);
//                new_position := r1.origin + r1.direction * t1;
//
//                if first_update {
//                    engine.editor.transform_gizmo.first_hit_position = new_position;
//                }
//
//                position_change := new_position - engine.editor.transform_gizmo.first_hit_position;
//				scale_speed := ifx key_pressed(.SHIFT) then 4.0 else 1.0;
//
//                if selected_entity.uses_uniform_scale {
//                    current_scale := selected_entity.transform.scale;
//					
//                    if engine.editor.transform_gizmo.selected_axis == {
//                        case .UP; {
//                            current_scale.y = engine.editor.transform_gizmo.actual_entity_scale.y + position_change.y * scale_speed;
//                            position_change.x = 0;
//                            position_change.z = 0;
//                        }
//                        case .FORWARD; {
//                            current_scale.z = engine.editor.transform_gizmo.actual_entity_scale.z + position_change.z * scale_speed;
//                            position_change.x = 0;
//                            position_change.y = 0;
//                        }
//                        case .RIGHT; {
//                            current_scale.x = engine.editor.transform_gizmo.actual_entity_scale.x + position_change.x * scale_speed;
//                            position_change.y = 0;
//                            position_change.z = 0;
//                        }
//                        case .CENTER; {
//                            current_scale.x = engine.editor.transform_gizmo.actual_entity_scale.x + position_change.x * scale_speed;
//                            current_scale.y = current_scale.x; // @Incomplete: This is most definitely wrong!
//                            current_scale.z = current_scale.x;
//
//                            position_change.y = 0;
//                            position_change.z = 0;
//                        }
//                    }
//
//                    set_scale(*selected_entity.transform, current_scale);
//
//                } else {
//                    if engine.editor.transform_gizmo.selected_axis == {
//                        case .UP;
//                        position_change.x = 0;
//                        position_change.z = 0;
//                        case .FORWARD;
//                        position_change.x = 0;
//                        position_change.y = 0;
//                        case .RIGHT;
//                        position_change.y = 0;
//                        position_change.z = 0;
//                    }
//
//                    entity_scale := engine.editor.transform_gizmo.actual_entity_scale + position_change * scale_speed;
//                    set_scale(*selected_entity.transform, entity_scale);
//                }
//            }
//
//            color_up := engine.editor.transform_gizmo.color_up;
//            color_forward := engine.editor.transform_gizmo.color_forward;
//            color_right := engine.editor.transform_gizmo.color_right;
//            color_center := Color.{1,1,1,1};
//
//            if engine.editor.transform_gizmo.selected_axis == {
//                case .NONE;
//                case .UP;
//                color_up = Color.{1,1,0,1};
//                case .FORWARD;
//                color_forward = Color.{1,1,0,1};
//                case .RIGHT;
//                color_right = Color.{1,1,0,1};
//                case .CENTER;
//                color_center = Color.{1,1,0,1};
//            }
//
//            upload_data_to_buffer(engine.renderer, engine.editor.transform_gizmo.color_center_buffer, *color_center, size_of(Color));
//            upload_data_to_buffer(engine.renderer, engine.editor.transform_gizmo.color_up_buffer, *color_up, size_of(Color));
//            upload_data_to_buffer(engine.renderer, engine.editor.transform_gizmo.color_forward_buffer, *color_forward, size_of(Color));
//            upload_data_to_buffer(engine.renderer, engine.editor.transform_gizmo.color_right_buffer, *color_right, size_of(Color));
//    }
//
//    return engine.editor.transform_gizmo.selected_axis != .NONE;
}

update_gizmo_buffers :: () {
//    update_matrix(*engine.editor.transform_gizmo.transform);
//
//    up_rotation := rotation_matrix(Matrix3, euler_to_quaternion(degrees_to_radians(90), degrees_to_radians(90), degrees_to_radians(0)));
//    right_rotation := rotation_matrix(Matrix3, euler_to_quaternion(degrees_to_radians(90), degrees_to_radians(0), degrees_to_radians(90)));
//    up_model := engine.editor.transform_gizmo.transform.model_matrix * up_rotation;
//    right_model := engine.editor.transform_gizmo.transform.model_matrix * right_rotation;
//    center_scale := make_scale_matrix4(.{0.15, 0.15, 0.15});
//    center_model := engine.editor.transform_gizmo.transform.model_matrix * center_scale;
//
//    upload_data_to_buffer(engine.renderer, engine.editor.transform_gizmo.center_model_buffer, *center_model, size_of(Matrix4));
//    upload_data_to_buffer(engine.renderer, engine.editor.transform_gizmo.up_model_buffer, *up_model, size_of(Matrix4));
//    upload_data_to_buffer(engine.renderer, engine.editor.transform_gizmo.forward_model_buffer, *engine.editor.transform_gizmo.transform.model_matrix, size_of(Matrix4));
//    upload_data_to_buffer(engine.renderer, engine.editor.transform_gizmo.right_model_buffer, *right_model, size_of(Matrix4));
}


#load "editor_ui.jai";