use clap::{Parser, Subcommand};
mod markdown;
use markdown::{get_all_posts, get_post_by_slug, get_posts_by_tag, watch_posts};
use serde_json;
use std::fs;

#[derive(Parser)]
#[command(name = "Markdown Backend")]
#[command(about = "A CLI for managing markdown blog posts", long_about = None)]
struct Cli {
    #[command(subcommand)]
    command: Commands,
}

#[derive(Subcommand)]
enum Commands {
    /// List all posts
    List,
    /// Show a post by slug
    Show {
        slug: String,
    },
    /// List posts by tag
    Tags {
        tag: String,
    },
    /// Watch for changes in the posts directory
    Watch,
    /// Show Rust parser statistics
    Rsparseinfo,
}

fn main() {
    markdown::load_post_cache_from_disk();
    let cli = Cli::parse();
    match &cli.command {
        Commands::List => {
            let posts = get_all_posts().unwrap_or_else(|e| {
                eprintln!("{}", e);
                std::process::exit(1);
            });
            println!("{}", serde_json::to_string(&posts).unwrap());
        }
        Commands::Show { slug } => {
            match get_post_by_slug(slug) {
                Ok(post) => {
                    println!("{}", serde_json::to_string(&post).unwrap());
                    markdown::save_post_cache_to_disk();
                }
                Err(e) => {
                    eprintln!("{}", e);
                    std::process::exit(1);
                }
            }
        }
        Commands::Tags { tag } => {
            let posts = get_posts_by_tag(tag).unwrap_or_else(|e| {
                eprintln!("{}", e);
                std::process::exit(1);
            });
            println!("{}", serde_json::to_string(&posts).unwrap());
        }
        Commands::Watch => {
            println!("Watching for changes in posts directory. Press Ctrl+C to exit.");
            let _ = watch_posts(|| {
                println!("Posts directory changed!");
            });
            // Keep the main thread alive
            loop {
                std::thread::sleep(std::time::Duration::from_secs(60));
            }
        }
        Commands::Rsparseinfo => {
            println!("{}", markdown::rsparseinfo());
        }
    }
}