use std::env;
use std::error::Error;
use std::process::exit;
use std::io::{stdout, stdin, Write};
use std::num::Wrapping;
use colored::*;
use gclone::Cache;

fn flush_stdout() {
    stdout().flush().ok();
}

fn main() {
    let cache = Cache::read();

    let request = match env::args().nth(1) {
        Some(arg) => arg,
        None => {
            eprintln!("{} {}",
                "error:".bold().red(),
                "cdg expects an argument".bold());

            exit(1);
        },
    };

    let matches = cache.find(&request);

    match matches.len() {
        0 => {
            eprintln!("{} {}",
                "error:".bold().red(),
                "no such directory".bold());

            exit(1);
        },

        1 => {
            println!("{}", matches[0]);
        },

        len => {

            eprintln!("{} {}",
                "info:".bold(),
                "multiple entries found, please select one");

            for (i, j) in matches.iter().enumerate() {
                eprintln!("[{}] {}", i + 1, j);
            }

            eprint!("Enter your choice: ");
            flush_stdout();

            let mut string = String::new();
            match stdin().read_line(&mut string) {
                Ok(_) => (),
                Err(e) => {
                    eprintln!("{} {} {}",
                        "error:".bold().red(),
                        "couldn't read line:".bold(),
                        e.description());

                    exit(1);
                },
            };

            // Pop the trailing \n of the string
            string.pop();

            // Use wrapping to move 0 to std::usize::MAX which is ok.
            let value = (Wrapping(match string.parse::<usize>() {
                Ok(v) => v,
                Err(e) => {
                    eprintln!("{} {} {}",
                        "error:".bold().red(),
                        "couldn't parse integer:".bold(),
                        e.description());

                    exit(1);
                }
            }) - Wrapping(1)).0;

            if value >= len {
                eprintln!("{} {}",
                    "error:".bold().red(),
                    "integer wasn't in the right range".bold());

                exit(1);
            }

            println!("{}", matches[value]);

        },
    }


}