use std::env;
use std::process::exit;
use std::error::Error;
use std::path::PathBuf;
use std::fs::File;
use std::io::{Write, BufRead, BufReader};

use colored::*;

pub fn git_dir() -> String {
    match env::var("GCLONE_PATH") {
        Ok(path) => path,
        Err(e) => {
            eprintln!("{} {} {}",
                "error:".bold().red(),
                "environment variable GCLONE_PATH must be set:".bold(),
                e.description());

            exit(1);
        },
    }
}

pub struct Cache(Vec<String>);

impl Cache {
    pub fn read() -> Cache {

        let mut path = PathBuf::from(git_dir());
        path.push(".cdgcache");

        let file = match File::open(&path) {
            Ok(f) => f,
            Err(_) => return Cache(vec![]),
        };

        let file = BufReader::new(file);

        let mut values = vec![];

        for line in file.lines() {
            if let Ok(l) = line {
                values.push(l);
            }
        }

        Cache(values)
    }

    pub fn write(&self) -> Result<(), Box<Error>> {
        let mut path = PathBuf::from(git_dir());
        path.push(".cdgcache");
        let mut file = File::create(path)?;

        for line in &self.0 {
            writeln!(file, "{}", line)?;
        }

        Ok(())
    }

    pub fn find(&self, dirname: &str) -> Vec<String> {
        let dirname = &format!("/{}", dirname);
        let mut matches = vec![];
        for line in &self.0 {
            if line.ends_with(dirname) {
                matches.push(line.clone());
            }
        }

        matches
    }

    pub fn append(&mut self, value: String) {
        self.0.push(value);
    }
}