/*
 * Copyright 2013 Google Inc.
 * Copyright 2014 Andreas Schildbach
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *    http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package org.libdohj.params;

import org.bitcoinj.core.Utils;
import org.spongycastle.util.encoders.Hex;

import static com.google.common.base.Preconditions.checkState;
import java.io.ByteArrayOutputStream;
import org.bitcoinj.core.AltcoinBlock;
import org.bitcoinj.core.Block;
import static org.bitcoinj.core.Coin.COIN;
import org.bitcoinj.core.NetworkParameters;
import org.bitcoinj.core.Transaction;
import org.bitcoinj.core.TransactionInput;
import org.bitcoinj.core.TransactionOutput;
import org.bitcoinj.script.Script;
import org.bitcoinj.script.ScriptOpCodes;

/**
 * Parameters for the testnet, a separate public instance of Litecoin that has
 * relaxed rules suitable for development and testing of applications and new
 * Litecoin versions.
 */
public class LitecoinTestNet3Params extends AbstractLitecoinParams {
    public static final int TESTNET_MAJORITY_WINDOW = 1000;
    public static final int TESTNET_MAJORITY_REJECT_BLOCK_OUTDATED = 750;
    public static final int TESTNET_MAJORITY_ENFORCE_BLOCK_UPGRADE = 501;

    public LitecoinTestNet3Params() {
        super();
        id = ID_LITE_TESTNET;
        // Genesis hash is f5ae71e26c74beacc88382716aced69cddf3dffff24f384e1808905e0188f68f
        packetMagic = 0xfcc1b7dc;

        maxTarget = Utils.decodeCompactBits(0x1e0fffffL);
        port = 19333;
        addressHeader = 111;
        p2shHeader = 196;
        acceptableAddressCodes = new int[] { addressHeader, p2shHeader };
        dumpedPrivateKeyHeader = 239;

        this.genesisBlock = createGenesis(this);
        spendableCoinbaseDepth = 30;
        subsidyDecreaseBlockCount = 100000;

        String genesisHash = genesisBlock.getHashAsString();
        checkState(genesisHash.equals("f5ae71e26c74beacc88382716aced69cddf3dffff24f384e1808905e0188f68f"));
        alertSigningKey = Hex.decode("0449623fc74489a947c4b15d579115591add020e53b3490bf47297dfa3762250625f8ecc2fb4fc59f69bdce8f7080f3167808276ed2c79d297054367566038aa82");

        majorityEnforceBlockUpgrade = TESTNET_MAJORITY_ENFORCE_BLOCK_UPGRADE;
        majorityRejectBlockOutdated = TESTNET_MAJORITY_REJECT_BLOCK_OUTDATED;
        majorityWindow = TESTNET_MAJORITY_WINDOW;

        dnsSeeds = new String[] {
            "testnet-seed.litecointools.com",
            "testnet-seed.ltc.xurious.com",
            "dnsseed.wemine-testnet.com"
        };
        // Note this is the same as the BIP32 testnet, as BIP44 makes HD wallets
        // chain agnostic. Litecoin mainnet has its own headers for legacy reasons.
        bip32HeaderPub = 0x043587CF;
        bip32HeaderPriv = 0x04358394;
    }

    private static AltcoinBlock createGenesis(NetworkParameters params) {
        AltcoinBlock genesisBlock = new AltcoinBlock(params, Block.BLOCK_VERSION_GENESIS);
        Transaction t = new Transaction(params);
        try {
            byte[] bytes = Hex.decode
                    ("04ffff001d0104404e592054696d65732030352f4f63742f32303131205374657665204a6f62732c204170706c65e280997320566973696f6e6172792c2044696573206174203536");
            t.addInput(new TransactionInput(params, t, bytes));
            ByteArrayOutputStream scriptPubKeyBytes = new ByteArrayOutputStream();
            Script.writeBytes(scriptPubKeyBytes, Hex.decode
                    ("040184710fa689ad5023690c80f3a49c8f13f8d45b8c857fbcbc8bc4a8e4d3eb4b10f4d4604fa08dce601aaf0f470216fe1b51850b4acf21b179c45070ac7b03a9"));
            scriptPubKeyBytes.write(ScriptOpCodes.OP_CHECKSIG);
            t.addOutput(new TransactionOutput(params, t, COIN.multiply(50), scriptPubKeyBytes.toByteArray()));
        } catch (Exception e) {
            // Cannot happen.
            throw new RuntimeException(e);
        }
        genesisBlock.addTransaction(t);
        genesisBlock.setTime(1317798646L);
        genesisBlock.setDifficultyTarget(0x1e0ffff0L);
        genesisBlock.setNonce(385270584);
        return genesisBlock;
    }

    private static LitecoinTestNet3Params instance;
    public static synchronized LitecoinTestNet3Params get() {
        if (instance == null) {
            instance = new LitecoinTestNet3Params();
        }
        return instance;
    }

    @Override
    public String getPaymentProtocolId() {
        // TODO: CHANGE ME
        return PAYMENT_PROTOCOL_ID_TESTNET;
    }

    @Override
    public boolean isTestNet() {
        return true;
    }
}