// Copyright 2015-2020 Parity Technologies (UK) Ltd.
// This file is part of Open Ethereum.

// Open Ethereum is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.

// Open Ethereum is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.

// You should have received a copy of the GNU General Public License
// along with Open Ethereum.  If not, see <http://www.gnu.org/licenses/>.

#![warn(missing_docs)]

//! Dir utilities for platform-specific operations
extern crate app_dirs;
extern crate ethereum_types;
extern crate journaldb;
extern crate home;

pub mod helpers;
use std::fs;
use std::path::{PathBuf, Path};
use ethereum_types::{H64, H256};
use journaldb::Algorithm;
use helpers::{replace_home, replace_home_and_local};
use app_dirs::{AppInfo, get_app_root, data_root, AppDataType};
// re-export platform-specific functions
use platform::*;

pub use home::home_dir;

/// Platform-specific chains path for standard client - Windows only
#[cfg(target_os = "windows")] pub const CHAINS_PATH: &str = "$LOCAL/chains";
/// Platform-specific chains path for light client - Windows only
#[cfg(target_os = "windows")] pub const CHAINS_PATH_LIGHT: &str = "$LOCAL/chains_light";
/// Platform-specific chains path for standard client
#[cfg(not(target_os = "windows"))] pub const CHAINS_PATH: &str = "$BASE/chains";
/// Platform-specific chains path for light client
#[cfg(not(target_os = "windows"))] pub const CHAINS_PATH_LIGHT: &str = "$BASE/chains_light";

/// Platform-specific cache path - Windows only
#[cfg(target_os = "windows")] pub const CACHE_PATH: &str = "$LOCAL/cache";
/// Platform-specific cache path
#[cfg(not(target_os = "windows"))] pub const CACHE_PATH: &str = "$BASE/cache";

// this const is irrelevent cause we do have migrations now,
// but we still use it for backwards compatibility
const LEGACY_CLIENT_DB_VER_STR: &str = "5.3";

#[derive(Debug, PartialEq)]
/// Parity local data directories
pub struct Directories {
	/// Base dir
	pub base: String,
	/// Database dir
	pub db: String,
	/// Cache dir
	pub cache: String,
	/// Dir to store keys
	pub keys: String,
	/// Signer dir
	pub signer: String,
	/// Secrets dir
	pub secretstore: String,
}

impl Default for Directories {
	fn default() -> Self {
		let data_dir = default_data_path();
		let local_dir = default_local_path();
		Directories {
			base: replace_home(&data_dir, "$BASE"),
			db: replace_home_and_local(&data_dir, &local_dir, CHAINS_PATH),
			cache: replace_home_and_local(&data_dir, &local_dir, CACHE_PATH),
			keys: replace_home(&data_dir, "$BASE/keys"),
			signer: replace_home(&data_dir, "$BASE/signer"),
			secretstore: replace_home(&data_dir, "$BASE/secretstore"),
		}
	}
}

impl Directories {
	/// Create local directories
	pub fn create_dirs(&self, signer_enabled: bool, secretstore_enabled: bool) -> Result<(), String> {
		fs::create_dir_all(&self.base).map_err(|e| e.to_string())?;
		fs::create_dir_all(&self.db).map_err(|e| e.to_string())?;
		fs::create_dir_all(&self.cache).map_err(|e| e.to_string())?;
		fs::create_dir_all(&self.keys).map_err(|e| e.to_string())?;
		if signer_enabled {
			fs::create_dir_all(&self.signer).map_err(|e| e.to_string())?;
		}
		if secretstore_enabled {
			fs::create_dir_all(&self.secretstore).map_err(|e| e.to_string())?;
		}
		Ok(())
	}

	/// Database paths.
	pub fn database(&self, genesis_hash: H256, fork_name: Option<String>, spec_name: String) -> DatabaseDirectories {
		DatabaseDirectories {
			path: self.db.clone(),
			legacy_path: self.base.clone(),
			genesis_hash,
			fork_name,
			spec_name,
		}
	}

	/// Get the ipc sockets path
	pub fn ipc_path(&self) -> PathBuf {
		let mut dir = Path::new(&self.base).to_path_buf();
		dir.push("ipc");
		dir
	}

	/// Legacy keys path
	// TODO: remove in 1.7
	pub fn legacy_keys_path(&self, testnet: bool) -> PathBuf {
		let mut dir = Path::new(&self.base).to_path_buf();
		if testnet {
			dir.push("testnet_keys");
		} else {
			dir.push("keys");
		}
		dir
	}

	/// Get the keys path
	pub fn keys_path(&self, data_dir: &str) -> PathBuf {
		let mut dir = PathBuf::from(&self.keys);
		dir.push(data_dir);
		dir
	}
}

#[derive(Debug, PartialEq)]
/// Database directories for the given fork.
pub struct DatabaseDirectories {
	/// Base path
	pub path: String,
	/// Legacy path
	pub legacy_path: String,
	/// Genesis hash
	pub genesis_hash: H256,
	/// Name of current fork
	pub fork_name: Option<String>,
	/// Name of current spec
	pub spec_name: String,
}

impl DatabaseDirectories {
	/// Base DB directory for the given fork.
	// TODO: remove in 1.7
	pub fn legacy_fork_path(&self) -> PathBuf {
		let gh = H64::from_slice(&self.genesis_hash.as_bytes()[20..28]);
		Path::new(&self.legacy_path).join(format!(
			"{:x}{}",
			gh,
			self.fork_name.as_ref().map(|f| format!("-{}", f)).unwrap_or_default()
		))
	}

	/// Spec root directory for the given fork.
	pub fn spec_root_path(&self) -> PathBuf {
		Path::new(&self.path).join(&self.spec_name)
	}

	/// Generic client path
	pub fn client_path(&self, pruning: Algorithm) -> PathBuf {
		self.db_root_path().join(pruning.as_internal_name_str()).join("db")
	}

	/// DB root path, named after genesis hash
	pub fn db_root_path(&self) -> PathBuf {
		let gh = H64::from_slice(&self.genesis_hash.as_bytes()[20..28]);
		self.spec_root_path().join("db").join(format!("{:x}", gh))
	}

	/// DB path
	pub fn db_path(&self, pruning: Algorithm) -> PathBuf {
		self.db_root_path().join(pruning.as_internal_name_str())
	}

	/// Get the root path for database
	// TODO: remove in 1.7
	pub fn legacy_version_path(&self, pruning: Algorithm) -> PathBuf {
		self.legacy_fork_path().join(format!("v{}-sec-{}", LEGACY_CLIENT_DB_VER_STR, pruning.as_internal_name_str()))
	}

	/// Get user defaults path, legacy way
	// TODO: remove in 1.7
	pub fn legacy_user_defaults_path(&self) -> PathBuf {
		self.legacy_fork_path().join("user_defaults")
	}

	/// Get snapshot path, legacy way
	// TODO: remove in 1.7
	pub fn legacy_snapshot_path(&self) -> PathBuf {
		self.legacy_fork_path().join("snapshot")
	}

	/// Get user defaults path, legacy way
	// TODO: remove in 1.7
	pub fn legacy_network_path(&self) -> PathBuf {
		self.legacy_fork_path().join("network")
	}

	/// Get user defauls path
	pub fn user_defaults_path(&self) -> PathBuf {
		self.spec_root_path().join("user_defaults")
	}

	/// Get the path for the snapshot directory given the genesis hash and fork name.
	pub fn snapshot_path(&self) -> PathBuf {
		self.db_root_path().join("snapshot")
	}

	/// Get the path for the network directory.
	pub fn network_path(&self) -> PathBuf {
		self.spec_root_path().join("network")
	}
}

fn default_path(t: AppDataType) -> Option<PathBuf> {
	let app_info = AppInfo { name: PRODUCT, author: AUTHOR };
	let old_root = get_app_root(t, &app_info).ok()?;
	if old_root.exists() {
		return Some(old_root);
	}

	let mut root = data_root(t).ok()?;
	root.push(if LOWERCASE { "openethereum" } else { "OpenEthereum" });
	Some(root)
}

fn fallback_path() -> PathBuf {
	let mut p = PathBuf::new();
	p.push("$HOME");
	p.push(".openethereum");
	p
}

/// Default data path
pub fn default_data_pathbuf() -> PathBuf {
	default_path(AppDataType::UserData).unwrap_or_else(fallback_path)
}

/// Default data path
pub fn default_data_path() -> String {
	default_data_pathbuf().to_string_lossy().into_owned()
}

/// Default local path
pub fn default_local_path() -> String {
	default_path(AppDataType::UserCache).unwrap_or_else(fallback_path).to_string_lossy().into_owned()
}

/// Default hypervisor path
pub fn default_hypervisor_path() -> PathBuf {
	let app_info = AppInfo { name: PRODUCT_HYPERVISOR, author: AUTHOR };
	get_app_root(AppDataType::UserData, &app_info).unwrap_or_else(|_| "$HOME/.parity-hypervisor".into())
}

/// Get home directory.
fn home() -> PathBuf {
	home_dir().expect("Failed to get home dir")
}

/// Geth path
pub fn geth(testnet: bool) -> PathBuf {
	let mut base = geth_base();
	if testnet {
		base.push("testnet");
	}
	base.push("keystore");
	base
}

#[cfg(target_os = "macos")]
mod platform {
	use std::path::PathBuf;
	pub const LOWERCASE: bool = false;
	pub const AUTHOR: &str = "Parity";
	pub const PRODUCT: &str = "io.parity.ethereum";
	pub const PRODUCT_HYPERVISOR: &str = "io.parity.ethereum-updates";

	pub fn geth_base() -> PathBuf {
		let mut home = super::home();
		home.push("Library");
		home.push("Ethereum");
		home
	}
}

#[cfg(windows)]
mod platform {
	use std::path::PathBuf;
	pub const LOWERCASE: bool = false;
	pub const AUTHOR: &str = "Parity";
	pub const PRODUCT: &str = "Ethereum";
	pub const PRODUCT_HYPERVISOR: &str = "EthereumUpdates";

	pub fn geth_base() -> PathBuf {
		let mut home = super::home();
		home.push("AppData");
		home.push("Roaming");
		home.push("Ethereum");
		home
	}
}

#[cfg(not(any(target_os = "macos", windows)))]
mod platform {
	use std::path::PathBuf;
	pub const LOWERCASE: bool = true;
	pub const AUTHOR: &str = "parity";
	pub const PRODUCT: &str = "io.parity.ethereum";
	pub const PRODUCT_HYPERVISOR: &str = "io.parity.ethereum-updates";

	pub fn geth_base() -> PathBuf {
		let mut home = super::home();
		home.push(".ethereum");
		home
	}
}

#[cfg(test)]
mod tests {
	use super::Directories;
	use helpers::{replace_home, replace_home_and_local};

	#[test]
	fn test_default_directories() {
		let data_dir = super::default_data_path();
		let local_dir = super::default_local_path();
		let expected = Directories {
			base: replace_home(&data_dir, "$BASE"),
			db: replace_home_and_local(&data_dir, &local_dir,
				if cfg!(target_os = "windows") { "$LOCAL/chains" }
				else { "$BASE/chains" }
			),
			cache: replace_home_and_local(&data_dir, &local_dir,
				if cfg!(target_os = "windows") { "$LOCAL/cache" }
				else { "$BASE/cache" }
			),
			keys: replace_home(&data_dir, "$BASE/keys"),
			signer: replace_home(&data_dir, "$BASE/signer"),
			secretstore: replace_home(&data_dir, "$BASE/secretstore"),
		};
		assert_eq!(expected, Directories::default());
	}
}
