use std::fs::File;
use std::path::{Path, PathBuf};

use serde::{Deserialize, Serialize};

pub mod rom;

#[derive(Deserialize, Serialize)]
pub struct Patch {
    pub address: usize,
    pub patch_data: Vec<u8>,
}

#[derive(Deserialize, Serialize)]
pub struct PatchSet {
    filename: PathBuf,
    patches: Vec<Patch>,
}

impl PatchSet {
    pub fn load(filename: &Path) -> Result<PatchSet, anyhow::Error> {
        let patches = {
            let file = File::open(filename)?;
            let buffer = std::io::BufReader::new(file);
            serde_json::from_reader(buffer)?
        };
        Ok(PatchSet {
            filename: filename.into(),
            patches: patches,
        })
    }

    pub fn filename(&self) -> &Path {
        self.filename.as_path()
    }

    pub fn patch_rom(self, rom: &mut RomData) {
        for patch in self.patches {
            rom.patch_data(patch);
        }
    }
}