/*
 * Copyright (C) Oscar Shrimpton 2020
 *
 * This program is free software: you can redistribute it and/or modify it
 * under the terms of the GNU General Public License as published by the Free
 * Software Foundation, either version 3 of the License, or (at your option)
 * any later version.
 *
 * 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 General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

use std::str;

use super::Q3BSPFile;
use crate::coords::CoordSystem;
use crate::helpers::slice_to_u32;
use crate::traits::effects::*;
use crate::types::{ParseError, Result};

/// The size of one effect definition
const EFFECT_SIZE: usize = 64 + 4 + 4;

pub fn from_data(data: &[u8], n_brushes: u32) -> Result<Box<[Effect]>> {
    if data.len() % EFFECT_SIZE != 0 {
        return Err(ParseError::Invalid);
    }
    let length = data.len() / EFFECT_SIZE;

    let mut effects = Vec::with_capacity(length);
    for n in 0..length {
        let raw = &data[n * EFFECT_SIZE..(n + 1) * EFFECT_SIZE];

        let brush_idx = slice_to_u32(&raw[64..68]);
        if brush_idx >= n_brushes {
            return Err(ParseError::Invalid);
        }

        effects.push(Effect {
            name: str::from_utf8(&raw[..64])
                .map_err(|_| ParseError::Invalid)?
                .to_owned(),
            brush_idx,
        });
    }

    Ok(effects.into_boxed_slice())
}

impl<T: CoordSystem> HasEffects<T> for Q3BSPFile<T> {
    type EffectsIter<'a> = std::slice::Iter<'a, Effect>;

    fn effects_iter(&self) -> Self::EffectsIter<'_> {
        self.effects.iter()
    }

    fn get_effect(&self, index: u32) -> &Effect {
        &self.effects[index as usize]
    }
}