/*
    wearechat - generic multiplayer game with voip
    Copyright (C) 2025 metamuffin

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License as published by
    the Free Software Foundation, version 3 of the License only.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Affero General Public License for more details.

    You should have received a copy of the GNU Affero General Public License
    along with this program.  If not, see <https://www.gnu.org/licenses/>.
*/
use glam::{Affine3A, EulerRot, Mat3, Mat4, Vec2, Vec3, vec3};

pub struct Camera {
    pos: Vec3,
    rot: Vec3,
    fov: f32,
    pub aspect: f32,
}

impl Default for Camera {
    fn default() -> Self {
        Self::new()
    }
}

impl Camera {
    pub fn new() -> Self {
        Self {
            aspect: 1.,
            fov: 1.,
            pos: Vec3::Z * 3.,
            rot: Vec3::ZERO,
        }
    }
    pub fn update(&mut self, input_move: Vec3, input_rot: Vec2, dt: f32) {
        let speed = 5.;
        let vel_local = vec3(input_move.z, input_move.y, -input_move.x) * dt * speed;
        self.pos += self.rotation_mat() * vel_local;
        self.rot.x += input_rot.x * -0.002;
        self.rot.y += input_rot.y * -0.002;
    }
    pub fn position(&self) -> Vec3 {
        self.pos
    }
    pub fn rotation(&self) -> Vec3 {
        self.rot
    }
    pub fn rotation_mat(&self) -> Mat3 {
        Mat3::from_euler(EulerRot::YXZ, self.rot.x, self.rot.y, self.rot.z)
    }
    pub fn view_matrix(&self) -> Mat4 {
        Mat4::from_mat3(self.rotation_mat().inverse()) * Mat4::from_translation(-self.pos)
    }
    pub fn project_matrix(&self) -> Mat4 {
        Mat4::perspective_rh(self.fov, self.aspect, 0.01, 300.)
    }
    pub fn new_ui_affine(&self) -> Affine3A {
        Affine3A::from_mat3_translation(
            self.rotation_mat(),
            self.pos + self.rotation_mat() * vec3(0., 0., -3.),
        )
    }
}