use std::path::PathBuf;

use crate::blog_post::BlogPost;
use crate::cli::parameters::BuildArgs;
use crate::config::Config;
use crate::error::CustomError;
use walkdir::WalkDir;

pub(crate) async fn build_site(args: BuildArgs) -> Result<(), CustomError> {
    let config = Config::load_from_file(args.config).await?;
    let root_directory = config.get_root_directory().to_owned();
    let output_directory = get_output_directory(&config).await?;
    let post_directories = WalkDir::new(config.get_posts_directory())
        .into_iter()
        .filter(|e| match e {
            Ok(entry) if entry.depth() == 1 && entry.file_type().is_dir() => true,
            Ok(_) => false,
            Err(_) => true,
        })
        .collect::<Result<Vec<_>, _>>()?;
    let load_jobs = post_directories
        .into_iter()
        .map(walkdir::DirEntry::into_path)
        .map(|path| tokio::spawn(BlogPost::load_blog_post(root_directory.clone(), path)));
    let mut blog_posts = Vec::new();
    for job in load_jobs {
        blog_posts.push(job.await??);
    }
    println!("{:?}", blog_posts);
    Ok(())
}

/// Delete everything inside the output directory and return the path to that directory.
async fn get_output_directory(config: &Config) -> Result<PathBuf, CustomError> {
    let output_directory = config.get_output_directory();
    if !output_directory.exists() {
        tokio::fs::create_dir(&output_directory).await?;
    } else {
        let mut existing_entries = tokio::fs::read_dir(&output_directory).await?;
        while let Some(entry) = existing_entries.next_entry().await? {
            let file_type = entry.file_type().await?;
            if file_type.is_dir() {
                tokio::fs::remove_dir_all(entry.path()).await?;
            } else {
                tokio::fs::remove_file(entry.path()).await?;
            }
        }
    }
    Ok(output_directory)
}