use std::error::Error;
use std::fmt;
use std::path::Path;
use libpijul::pristine::sanakirja::Pristine;
use libpijul::TxnT;
use libpijul::TxnTExt;
pub struct Repository {
    pristine: Pristine,
}
pub struct Change {
    pub hash: String,
}
#[derive(Debug, Clone)]
pub struct NoSuchChannelError {
    channel_name: String,
}
impl fmt::Display for NoSuchChannelError {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        write!(f, "no such channel: {}", self.channel_name)
    }
}
impl Error for NoSuchChannelError {}
impl Repository {
    pub fn load(path: &str) -> Result<Repository, Box<dyn Error>> {
        let repo_path = Path::new(path);
        let pristine_path = repo_path.join(".pijul/pristine/db");
        let pristine = Pristine::new(pristine_path)?;
        return Ok(Repository {
            pristine,
        });
    }
    pub fn log(&mut self, channel_name: &str) -> Result<Vec<Change>, Box<dyn Error>> {
        let txn = self.pristine.txn_begin()?;
        let channel = txn.load_channel(&channel_name)?.ok_or(NoSuchChannelError {
            channel_name: channel_name.to_string(),
        })?;
        let log = txn.log(&*channel.read(), 0)?;
        let mut changes: Vec<Change> = Vec::new();
        for pr in log {
            let (_, (h, _)) = pr?;
            changes.push(Change {
                hash: format!("{:?}", h),
            });
        }
        return Ok(changes);
    }
}

use std::path::Path;

use libpijul::pristine::sanakirja::Pristine;
use libpijul::TxnT;
use libpijul::TxnTExt;

mod repo;
use repo::Repository;

    let repo = matches.opt_str("r").unwrap_or(".".to_string());
    let repo_path = Path::new(&repo);
    let pristine_path = repo_path.join(".pijul/pristine/db");

    let repo_path = matches.opt_str("r").unwrap_or(".".to_string());

    let pristine = Pristine::new(pristine_path).unwrap();
    let txn = pristine.txn_begin().unwrap();
    let channel_name = txn.current_channel().unwrap();
    println!("On channel {}", channel_name);
    let channel = txn.load_channel(channel_name).unwrap().unwrap();
    let rev_log = txn.reverse_log(&*channel.read(), None).unwrap();
    for pr in rev_log {
        let (_, (h, _)) = pr.unwrap();
        println!("{:?}", h);

    let mut repo = Repository::load(&repo_path).unwrap();
    let changes = repo.log("main").unwrap();
    for c in changes {
        println!("{}", c.hash);