// 
// MIT License
//
// Copyright (c) 2018-2019 Open Zesame (https://github.com/OpenZesame)
// 
// Permission is hereby granted, free of charge, to any person obtaining a copy
// of this software and associated documentation files (the "Software"), to deal
// in the Software without restriction, including without limitation the rights
// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
// copies of the Software, and to permit persons to whom the Software is
// furnished to do so, subject to the following conditions:
// 
// The above copyright notice and this permission notice shall be included in all
// copies or substantial portions of the Software.
// 
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
// SOFTWARE.
//

import Foundation
import EllipticCurveKit

import CryptoSwift

public extension Keystore {

    static func from(
        privateKey: PrivateKey,
        encryptBy password: String,
        kdf: KDF,
        kdfParams: KDFParams? = nil,
        done: @escaping Done<Keystore>
    ) throws {

        guard password.count >= Keystore.minumumPasswordLength else {
            let error = Error.keystorePasswordTooShort(
                provided: password.count,
                minimum: Keystore.minumumPasswordLength
            )
            done(.failure(error))
            return
        }

        let kdfParams = kdfParams ?? KDF.defaultParameters

        try AnyKeyDeriving(kdf: kdf, kdfParams: kdfParams).deriveKey(password: password) { derivedKey in

            let keyStore = try Keystore(
                from: derivedKey,
                privateKey: privateKey,
                kdf: kdf,
                parameters: kdfParams
            )

            done(Result.success(keyStore))
        }
    }
}
