/*
    This file is part of jellything (https://codeberg.org/metamuffin/jellything)
    which is licensed under the GNU Affero General Public License (version 3); see /COPYING.
    Copyright (C) 2026 metamuffin <metamuffin.org>
*/

use crate::Object;

pub trait Value<'a>: Sized {
    const ALIGNED: bool;
    fn load_aligned(buf: &'a [u32]) -> Option<Self> {
        let _ = buf;
        None
    }
    fn load_unaligned(buf: &'a [u8]) -> Option<Self> {
        let _ = buf;
        None
    }
    fn store(&self, buf: &mut Vec<u8>);
    fn size(&self) -> usize;
}
impl<'a> Value<'a> for &'a str {
    const ALIGNED: bool = false;
    fn load_unaligned(buf: &'a [u8]) -> Option<Self> {
        str::from_utf8(buf).ok()
    }
    fn store(&self, buf: &mut Vec<u8>) {
        buf.extend(self.as_bytes());
    }
    fn size(&self) -> usize {
        self.len()
    }
}
impl Value<'_> for u32 {
    const ALIGNED: bool = false;
    fn load_aligned(buf: &[u32]) -> Option<Self> {
        buf.get(0).copied()
    }
    fn store(&self, buf: &mut Vec<u8>) {
        buf.extend(self.to_ne_bytes());
    }
    fn size(&self) -> usize {
        4
    }
}
impl Value<'_> for u64 {
    const ALIGNED: bool = false;
    fn load_aligned(buf: &[u32]) -> Option<Self> {
        let hi = *buf.get(0)? as u64;
        let lo = *buf.get(1)? as u64;
        Some(hi << 32 | lo)
    }
    fn store(&self, buf: &mut Vec<u8>) {
        buf.extend(self.to_ne_bytes());
    }
    fn size(&self) -> usize {
        8
    }
}
impl<'a> Value<'a> for Object<'a> {
    const ALIGNED: bool = true;
    fn load_aligned(buf: &'a [u32]) -> Option<Self> {
        Self::load(buf)
    }
    fn store(&self, buf: &mut Vec<u8>) {
        buf.extend(self.tags.iter().copied().map(u32::to_ne_bytes).flatten());
        buf.extend(self.offsets.iter().copied().map(u32::to_ne_bytes).flatten());
        buf.extend(self.values.iter().copied().map(u32::to_ne_bytes).flatten());
    }
    fn size(&self) -> usize {
        (self.tags.len() + self.offsets.len() + self.values.len()) * size_of::<u32>()
    }
}