use ignore::{Walk, WalkBuilder};
use std::{path::PathBuf, vec::IntoIter};
use tracing::warn;

pub use config::{Config, PathEntry};
pub use error::Error;

mod config;
mod error;

pub struct Paths {
    paths_iter: IntoIter<PathEntry>,
    iter: Option<Walk>,
}

impl Paths {
    pub fn new(path_entries: Vec<PathEntry>) -> Self {
        Self {
            paths_iter: path_entries.into_iter(),
            iter: None,
        }
    }
}

impl From<&Config> for Paths {
    fn from(value: &Config) -> Self {
        Self::new(value.paths.to_owned())
    }
}

impl Iterator for Paths {
    type Item = PathBuf;

    #[tracing::instrument(skip(self))]
    fn next(&mut self) -> Option<Self::Item> {
        loop {
            match self.iter.as_mut().and_then(|iter| iter.next()) {
                Some(Ok(d)) => return Some(d.into_path()),
                Some(Err(err)) => warn!("{:?}", err),
                None => {
                    let next = self.paths_iter.next()?;
                    self.iter = Some(
                        WalkBuilder::new(next.path)
                            .standard_filters(true)
                            .max_depth(next.recurse)
                            .hidden(next.hidden)
                            .build(),
                    );
                }
            };
        }
    }
}

#[cfg(test)]
mod tests {
    use std::fs;

    use super::*;

    #[test]
    fn test_iteration() {
        let test_dir = tempfile::Builder::new()
            .tempdir()
            .expect("Failed to create tmp directory");

        let test_path = test_dir.path().to_owned();

        let mut projects = Vec::from([
            test_path.join("projects"),
            test_path.join("projects/project1"),
            test_path.join("projects/project2"),
            test_path.join("project3"),
            test_path.join("other_projects/project3"),
        ]);

        projects.iter().for_each(|project| {
            fs::create_dir_all(project).expect("Failed to create test project directory");
        });

        let directories = Paths::new(Vec::from([
            PathEntry {
                path: test_path.join("projects"),
                hidden: false,
                recurse: Some(1),
            },
            PathEntry {
                path: test_path.join("project3"),
                hidden: false,
                recurse: Some(0),
            },
            PathEntry {
                path: test_path.join("other_projects/project3"),
                hidden: false,
                recurse: Some(0),
            },
        ]));

        let mut actual = directories.into_iter().collect::<Vec<PathBuf>>();

        projects.sort();
        actual.sort();

        assert_eq!(projects, actual);
    }
}