import * as types from './types';

/**
 * Key DAO Interface, to be implemented by apps if they need the key management.
 */
export interface KeyDAO {
    /**
     * Save the encrypted private key to app
     *
     * @param name Name of the key
     * @param key The encrypted private key object
     * @throws `SdkError` if the save fails.
     */
    write(name: string, key: types.Key): void;

    /**
     * Get the encrypted private key by name
     *
     * @param name Name of the key
     * @returns The encrypted private key object or undefined
     */
    read(name: string): types.Key;

    /**
     * Delete the key by name
     * @param name Name of the key
     * @throws `SdkError` if the deletion fails.
     */
    delete(name: string): void;

    /**
     * Optional function to encrypt the private key by yourself. Default to AES Encryption
     * @param privKey The plain private key
     * @param password The password to encrypt the private key
     * @returns The encrypted private key
     * @throws `SdkError` if encrypt failed
     */
    encrypt?(privKey: string, password: string): string;

    /**
     * Optional function to decrypt the private key by yourself. Default to AES Decryption
     * @param encrptedPrivKey The encrpted private key
     * @param password The password to decrypt the private key
     * @returns The plain private key
     * @throws `SdkError` if decrypt failed
     */
    decrypt?(encrptedPrivKey: string, password: string): string;
}



/** Cache KeyDAO */
export class CacheKeyDAO implements KeyDAO {

    keyMap: { [key: string]: types.Key } = {};
    write(name: string, key: types.Key) {
        this.keyMap[name] = key;
    }
    read(name: string): types.Key {
        return this.keyMap[name];
    }
    delete(name: string) {
        delete this.keyMap[name];
    }
}