//! The output generated by this example must be used with the `dot` command coming from the `graphviz` package.
//! /!\ As the tree is really large, this example only prints the first root node.
//! If you want to get general stats about your database see the `stats` example.

use std::fs::File;
use std::io::BufWriter;
use std::path::PathBuf;

use arroy::distances::DotProduct;
use arroy::{Database, Reader};
use clap::Parser;
use heed::EnvOpenOptions;

#[derive(Parser)]
#[command(author, version, about, long_about = None)]
struct Cli {
    /// Sets a custom database path.
    #[arg(default_value = "import.ary")]
    database: PathBuf,

    /// Sets the output path for the graph.
    #[arg(long, default_value = "graph.dot")]
    output_path: PathBuf,
}

fn main() {
    let Cli { database, output_path } = Cli::parse();

    let output = File::create(&output_path).unwrap();
    let writer = BufWriter::new(output);

    let env = unsafe {
        EnvOpenOptions::new()
            .map_size(1024 * 1024 * 1024 * 2) // 2GiB
            .open(database)
    }
    .unwrap();

    let rtxn = env.read_txn().unwrap();
    let database: Database<DotProduct> =
        env.database_options().types().open(&rtxn).unwrap().unwrap();

    let reader = Reader::<DotProduct>::open(&rtxn, 0, database).unwrap();

    reader.plot_internals_tree_nodes(&rtxn, writer).unwrap();

    eprintln!("To convert the graph to a png, run: `dot {output_path:?} -T png > graph.png`");
    eprintln!("`dot` comes from the graphiz package");
}