extern crate serde;

#[macro_use]
extern crate serde_derive;

use chrono::Utc;
use clap::{App, Arg};
use regex::Regex;
use std::fs::{copy, create_dir, create_dir_all};
use std::path::PathBuf;

mod albatross_config;

use albatross_config::{AlbatrossConfig, WorldConfig, WorldType};

struct Region {
    x: i64,
    y: i64,
}

impl Region {
    fn from_string(string: String) -> Option<Self> {
        let re = Regex::new(r"r\.(?P<x>-?[0-9])+\.(?P<y>-?[0-9])").unwrap();
        if re.is_match(string.as_str()) {
            let captures = re.captures(string.as_str()).unwrap();

            return Some(Region {
                x: captures["x"].parse::<i64>().unwrap(),
                y: captures["y"].parse::<i64>().unwrap(),
            });
        }

        None
    }
}

fn backup_dir(
    dir_name: &str,
    world_path: &PathBuf,
    backup_path: &PathBuf,
) -> Result<(), std::io::Error> {
    let mut src_dir = world_path.clone();
    src_dir.push(dir_name);
    let mut backup_dir = backup_path.clone();
    backup_dir.push(dir_name);
    create_dir(&backup_dir)?;

    for entry in src_dir.read_dir().unwrap() {
        let entry = entry.unwrap();
        let mut target = backup_dir.clone();
        target.push(entry.file_name());

        copy(entry.path(), target)?;
    }

    Ok(())
}

fn backup_region(
    dir_name: &str,
    save_radius: u64,
    world_path: &PathBuf,
    backup_path: &PathBuf,
) -> Result<(), std::io::Error> {
    let mut src_dir = world_path.clone();
    src_dir.push(dir_name);
    let mut backup_dir = backup_path.clone();
    backup_dir.push(dir_name);
    create_dir(&backup_dir)?;

    let save_radius = if save_radius < 512 {
        1 as i64
    } else {
        (save_radius / 512) as i64
    };

    for entry in src_dir.read_dir().unwrap() {
        let entry = entry.unwrap();
        let file_name = entry.file_name().to_str().unwrap().to_string();

        if let Some(region) = Region::from_string(file_name) {
            if region.x.abs() < save_radius && region.y.abs() < save_radius {
                let mut target = backup_dir.clone();
                target.push(entry.file_name());

                copy(entry.path(), target)?;
            }
        }
    }

    Ok(())
}

fn backup_world(
    world_path: PathBuf,
    backup_path: PathBuf,
    world_config: &WorldConfig,
) -> Result<(), std::io::Error> {
    let mut backup_path = backup_path.clone();
    backup_path.push(&world_config.world_name);
    create_dir(backup_path.as_path())?;

    backup_region("poi", world_config.save_radius, &world_path, &backup_path)?;
    backup_region(
        "region",
        world_config.save_radius,
        &world_path,
        &backup_path,
    )?;
    backup_dir("data", &world_path, &backup_path)?;

    Ok(())
}

fn backup_overworld(
    world_path: PathBuf,
    backup_path: PathBuf,
    world_config: &WorldConfig,
) -> Result<(), std::io::Error> {
    backup_world(world_path, backup_path, world_config)?;
    Ok(())
}

fn do_backup(cfg: AlbatrossConfig) -> Result<(), std::io::Error> {
    let server_base_dir = cfg.backup.minecraft_dir.clone();
    let worlds = cfg.world_config.unwrap().clone();
    let time_str = Utc::now().format("%d-%m-%y_%H:%M%S").to_string();
    let backup_name = format!("{}-backup", time_str);
    let mut tmp_dir = cfg.backup.output_dir.clone();
    tmp_dir.push(backup_name);

    create_dir_all(tmp_dir.clone()).unwrap();

    for world in worlds {
        let mut world_dir = server_base_dir.clone();
        let world_name = world.world_name.clone();
        let world_type = match world.world_type.clone() {
            Some(world_type) => world_type,
            None => WorldType::OVERWORLD,
        };
        world_dir.push(world_name.clone());

        if world_dir.exists() && world_dir.is_dir() {
            match world_type {
                WorldType::OVERWORLD => {
                    backup_overworld(world_dir, tmp_dir.clone(), &world)?;
                }
                _ => {}
            };
        } else {
            println!("World \"{}\" not found", world_name.clone());
        }
    }

    Ok(())
}

fn main() {
    let mut app = App::new("Albatross").about("Backup your worlds").arg(
        Arg::with_name("config")
            .index(1)
            .short("c")
            .long("config")
            .value_name("CONFIG_PATH")
            .help("Config file path"),
    );
    // Get arg parser
    let matches = app.clone().get_matches();

    if let Some(cfg_path) = matches.value_of("config") {
        let cfg = AlbatrossConfig::new(cfg_path).expect("Config not found");

        if cfg.world_config.is_some() {
            match do_backup(cfg) {
                Err(e) => println!("Error doing backup: {}", e),
                _ => {}
            }
        } else {
            println!("No worlds specified to backed up!")
        }
    } else {
        app.print_help().expect("Unable to print help");
    }
}