use std::error::Error;
use crate::ScootalooError;
use reqwest::Url;
use tokio::{
    io::copy,
    fs::{File, create_dir_all},
};

/// Gets and caches Twitter Media inside the determined temp dir
pub async fn cache_media(u: &str, t: &str) -> Result<String, Box<dyn Error>> {
    // create dir
    create_dir_all(t).await?;

    // get file
    let mut response = reqwest::get(u).await?;

    // create local file
    let url = Url::parse(u)?;
    let dest_filename = url.path_segments().ok_or_else(|| ScootalooError::new(&format!("Cannot determine the destination filename for {}", u)))?
                    .last().ok_or_else(|| ScootalooError::new(&format!("Cannot determine the destination filename for {}", u)))?;

    let dest_filepath = format!("{}/{}", t, dest_filename);

    let mut dest_file = File::create(&dest_filepath).await?;

    while let Some(chunk) = response.chunk().await? {
        copy(&mut &*chunk, &mut dest_file).await?;
    }

    Ok(dest_filepath)
}

#[cfg(test)]
mod tests {
    use super::*;

    use std::{
        path::Path,
        fs::remove_dir_all,
    };

    const TMP_DIR: &'static str = "/tmp/scootaloo_test";

    #[tokio::test]
    async fn test_cache_media() {
        let dest = cache_media("https://forum.nintendojo.fr/styles/prosilver/theme/images/ndfr_casual.png", TMP_DIR).await.unwrap();

        assert!(Path::new(&dest).exists());

        remove_dir_all(TMP_DIR).unwrap();
    }
}