use crate::backup::uncompress_backup;
use crate::chunk_coordinate::ChunkCoordinate;
use crate::error::Result;
use anvil_region::AnvilChunkProvider;
use std::fs::remove_dir_all;
use std::path::PathBuf;

/// Struct for manipulating a world from a backup
struct RestoreAccess {
    /// Chunk source
    src_path: PathBuf,
    /// Chunk destination
    dest_path: PathBuf,
}

impl RestoreAccess {
    /// Create new RestoreAccess
    pub fn new(world_name: &str, src_path: &PathBuf, dest_path: &PathBuf) -> Result<Self> {
        let src_path = uncompress_backup(src_path)?.join(world_name).join("region");
        let dest_path = dest_path.join(world_name).join("region");

        Ok(RestoreAccess {
            src_path,
            dest_path,
        })
    }

    /// Copy chunk from source to desination
    pub fn copy_chunk(&self, x: i32, z: i32) {
        let src_provider = AnvilChunkProvider::new(self.src_path.to_str().unwrap());
        let dest_provider = AnvilChunkProvider::new(self.dest_path.to_str().unwrap());

        let chunk = src_provider.load_chunk(x, z).expect("Unable to load chunk");
        dest_provider
            .save_chunk(x, z, chunk)
            .expect("Unable to save chunk");
    }

    /// Cleanup process
    pub fn cleanup(self) -> Result<()> {
        Ok(remove_dir_all("tmp")?)
    }
}

/// Restore a range of chunks from a backup
pub fn restore_range_from_backup(
    world_name: &str,
    lower: ChunkCoordinate,
    upper: ChunkCoordinate,
    backup_path: &PathBuf,
    minecraft_dir: &PathBuf,
) -> Result<u64> {
    let chunk_access = RestoreAccess::new(world_name, backup_path, minecraft_dir)?;
    let mut count = 0;

    for x in lower.x..=upper.x {
        for z in lower.z..=upper.z {
            chunk_access.copy_chunk(x, z);
            count += 1;
        }
    }

    chunk_access.cleanup()?;
    Ok(count)
}

/// Restore a single chunk from a backup
pub fn restore_chunk_from_backup(
    world_name: &str,
    chunk: ChunkCoordinate,
    backup_path: &PathBuf,
    minecraft_dir: &PathBuf,
) -> Result<()> {
    let chunk_access = RestoreAccess::new(world_name, backup_path, minecraft_dir)?;
    chunk_access.copy_chunk(chunk.x, chunk.z);

    chunk_access.cleanup()?;
    Ok(())
}