const { describe, it } = require('mocha')
const assert = require('assert')
const bitcoin = require('../../')
const regtestUtils = require('./_regtest')
const regtest = regtestUtils.network

function rng () {
  return Buffer.from('YT8dAtK4d16A3P1z+TpwB2jJ4aFH3g9M1EioIBkLEV4=', 'base64')
}

describe('bitcoinjs-lib (transactions)', function () {
  it('can create a 1-to-1 Transaction', function () {
    const alice = bitcoin.ECPair.fromWIF('L1uyy5qTuGrVXrmrsvHWHgVzW9kKdrp27wBC7Vs6nZDTF2BRUVwy')
    const txb = new bitcoin.TransactionBuilder()

    txb.setVersion(1)
    txb.addInput('61d520ccb74288c96bc1a2b20ea1c0d5a704776dd0164a396efec3ea7040349d', 0) // Alice's previous transaction output, has 15000 satoshis
    txb.addOutput('1cMh228HTCiwS8ZsaakH8A8wze1JR5ZsP', 12000)
    // (in)15000 - (out)12000 = (fee)3000, this is the miner fee

    txb.sign(0, alice)

    // prepare for broadcast to the Bitcoin network, see "can broadcast a Transaction" below
    assert.strictEqual(txb.build().toHex(), '01000000019d344070eac3fe6e394a16d06d7704a7d5c0a10eb2a2c16bc98842b7cc20d561000000006b48304502210088828c0bdfcdca68d8ae0caeb6ec62cd3fd5f9b2191848edae33feb533df35d302202e0beadd35e17e7f83a733f5277028a9b453d525553e3f5d2d7a7aa8010a81d60121029f50f51d63b345039a290c94bffd3180c99ed659ff6ea6b1242bca47eb93b59fffffffff01e02e0000000000001976a91406afd46bcdfd22ef94ac122aa11f241244a37ecc88ac00000000')
  })

  it('can create a 2-to-2 Transaction', function () {
    const alice = bitcoin.ECPair.fromWIF('L1Knwj9W3qK3qMKdTvmg3VfzUs3ij2LETTFhxza9LfD5dngnoLG1')
    const bob = bitcoin.ECPair.fromWIF('KwcN2pT3wnRAurhy7qMczzbkpY5nXMW2ubh696UBc1bcwctTx26z')

    const txb = new bitcoin.TransactionBuilder()
    txb.setVersion(1)
    txb.addInput('b5bb9d8014a0f9b1d61e21e796d78dccdf1352f23cd32812f4850b878ae4944c', 6) // Alice's previous transaction output, has 200000 satoshis
    txb.addInput('7d865e959b2466918c9863afca942d0fb89d7c9ac0c99bafc3749504ded97730', 0) // Bob's previous transaction output, has 300000 satoshis
    txb.addOutput('1CUNEBjYrCn2y1SdiUMohaKUi4wpP326Lb', 180000)
    txb.addOutput('1JtK9CQw1syfWj1WtFMWomrYdV3W2tWBF9', 170000)
    // (in)(200000 + 300000) - (out)(180000 + 170000) = (fee)150000, this is the miner fee

    txb.sign(1, bob) // Bob signs his input, which was the second input (1th)
    txb.sign(0, alice) // Alice signs her input, which was the first input (0th)

    // prepare for broadcast to the Bitcoin network, see "can broadcast a Transaction" below
    assert.strictEqual(txb.build().toHex(), '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')
  })

  it('can create (and broadcast via 3PBP) a typical Transaction', function (done) {
    const alice1 = bitcoin.ECPair.makeRandom({ network: regtest })
    const alice2 = bitcoin.ECPair.makeRandom({ network: regtest })
    const aliceChange = bitcoin.ECPair.makeRandom({ network: regtest, rng: rng })

    const alice1pkh = bitcoin.payments.p2pkh({ pubkey: alice1.publicKey, network: regtest })
    const alice2pkh = bitcoin.payments.p2pkh({ pubkey: alice2.publicKey, network: regtest })
    const aliceCpkh = bitcoin.payments.p2pkh({ pubkey: aliceChange.publicKey, network: regtest })

    // give Alice 2 unspent outputs
    regtestUtils.faucet(alice1pkh.address, 5e4, function (err, unspent0) {
      if (err) return done(err)

      regtestUtils.faucet(alice2pkh.address, 7e4, function (err, unspent1) {
        if (err) return done(err)

        const txb = new bitcoin.TransactionBuilder(regtest)
        txb.addInput(unspent0.txId, unspent0.vout) // alice1 unspent
        txb.addInput(unspent1.txId, unspent1.vout) // alice2 unspent
        txb.addOutput('mwCwTceJvYV27KXBc3NJZys6CjsgsoeHmf', 8e4) // the actual "spend"
        txb.addOutput(aliceCpkh.address, 1e4) // Alice's change
        // (in)(4e4 + 2e4) - (out)(1e4 + 3e4) = (fee)2e4 = 20000, this is the miner fee

        // Alice signs each input with the respective private keys
        txb.sign(0, alice1)
        txb.sign(1, alice2)

        // build and broadcast our RegTest network
        regtestUtils.broadcast(txb.build().toHex(), done)
        // to build and broadcast to the actual Bitcoin network, see https://github.com/bitcoinjs/bitcoinjs-lib/issues/839
      })
    })
  })

  it('can create (and broadcast via 3PBP) a Transaction with an OP_RETURN output', function (done) {
    const keyPair = bitcoin.ECPair.makeRandom({ network: regtest })
    const p2pkh = bitcoin.payments.p2pkh({ pubkey: keyPair.publicKey, network: regtest })

    regtestUtils.faucet(p2pkh.address, 2e5, function (err, unspent) {
      if (err) return done(err)

      const txb = new bitcoin.TransactionBuilder(regtest)
      const data = Buffer.from('bitcoinjs-lib', 'utf8')
      const embed = bitcoin.payments.embed({ data: [data] })
      txb.addInput(unspent.txId, unspent.vout)
      txb.addOutput(embed.output, 1000)
      txb.addOutput(regtestUtils.RANDOM_ADDRESS, 1e5)
      txb.sign(0, keyPair)

      // build and broadcast to the RegTest network
      regtestUtils.broadcast(txb.build().toHex(), done)
    })
  })

  it('can create (and broadcast via 3PBP) a Transaction, w/ a P2SH(P2MS(2 of 4)) (multisig) input', function (done) {
    const keyPairs = [
      bitcoin.ECPair.makeRandom({ network: regtest }),
      bitcoin.ECPair.makeRandom({ network: regtest }),
      bitcoin.ECPair.makeRandom({ network: regtest }),
      bitcoin.ECPair.makeRandom({ network: regtest })
    ]
    const pubkeys = keyPairs.map(x => x.publicKey)
    const p2ms = bitcoin.payments.p2ms({ m: 2, pubkeys: pubkeys, network: regtest })
    const p2sh = bitcoin.payments.p2sh({ redeem: p2ms, network: regtest })

    regtestUtils.faucet(p2sh.address, 2e4, function (err, unspent) {
      if (err) return done(err)

      const txb = new bitcoin.TransactionBuilder(regtest)
      txb.addInput(unspent.txId, unspent.vout)
      txb.addOutput(regtestUtils.RANDOM_ADDRESS, 1e4)

      txb.sign(0, keyPairs[0], p2sh.redeem.output)
      txb.sign(0, keyPairs[2], p2sh.redeem.output)
      const tx = txb.build()

      // build and broadcast to the Bitcoin RegTest network
      regtestUtils.broadcast(tx.toHex(), function (err) {
        if (err) return done(err)

        regtestUtils.verify({
          txId: tx.getId(),
          address: regtestUtils.RANDOM_ADDRESS,
          vout: 0,
          value: 1e4
        }, done)
      })
    })
  })

  it('can create (and broadcast via 3PBP) a Transaction, w/ a P2SH(P2WPKH) input', function (done) {
    const keyPair = bitcoin.ECPair.makeRandom({ network: regtest })
    const p2wpkh = bitcoin.payments.p2wpkh({ pubkey: keyPair.publicKey, network: regtest })
    const p2sh = bitcoin.payments.p2sh({ redeem: p2wpkh, network: regtest })

    regtestUtils.faucet(p2sh.address, 5e4, function (err, unspent) {
      if (err) return done(err)

      const txb = new bitcoin.TransactionBuilder(regtest)
      txb.addInput(unspent.txId, unspent.vout)
      txb.addOutput(regtestUtils.RANDOM_ADDRESS, 2e4)
      txb.sign(0, keyPair, p2sh.redeem.output, null, unspent.value)

      const tx = txb.build()

      // build and broadcast to the Bitcoin RegTest network
      regtestUtils.broadcast(tx.toHex(), function (err) {
        if (err) return done(err)

        regtestUtils.verify({
          txId: tx.getId(),
          address: regtestUtils.RANDOM_ADDRESS,
          vout: 0,
          value: 2e4
        }, done)
      })
    })
  })

  it('can create (and broadcast via 3PBP) a Transaction, w/ a P2WPKH input', function (done) {
    const keyPair = bitcoin.ECPair.makeRandom({ network: regtest })
    const p2wpkh = bitcoin.payments.p2wpkh({ pubkey: keyPair.publicKey, network: regtest })

    regtestUtils.faucetComplex(p2wpkh.address, 5e4, function (err, unspent) {
      if (err) return done(err)

      // XXX: build the Transaction w/ a P2WPKH input
      const txb = new bitcoin.TransactionBuilder(regtest)
      txb.addInput(unspent.txId, unspent.vout, null, p2wpkh.output) // NOTE: provide the prevOutScript!
      txb.addOutput(regtestUtils.RANDOM_ADDRESS, 2e4)
      txb.sign(0, keyPair, null, null, unspent.value) // NOTE: no redeem script
      const tx = txb.build()

      // build and broadcast (the P2WPKH transaction) to the Bitcoin RegTest network
      regtestUtils.broadcast(tx.toHex(), function (err) {
        if (err) return done(err)

        regtestUtils.verify({
          txId: tx.getId(),
          address: regtestUtils.RANDOM_ADDRESS,
          vout: 0,
          value: 2e4
        }, done)
      })
    })
  })

  it('can create (and broadcast via 3PBP) a Transaction, w/ a P2WSH(P2PK) input', function (done) {
    const keyPair = bitcoin.ECPair.makeRandom({ network: regtest })
    const p2pk = bitcoin.payments.p2pk({ pubkey: keyPair.publicKey, network: regtest })
    const p2wsh = bitcoin.payments.p2wsh({ redeem: p2pk, network: regtest })

    regtestUtils.faucetComplex(p2wsh.address, 5e4, function (err, unspent) {
      if (err) return done(err)

      // XXX: build the Transaction w/ a P2WSH input
      const txb = new bitcoin.TransactionBuilder(regtest)
      txb.addInput(unspent.txId, unspent.vout, null, p2wsh.output) // NOTE: provide the prevOutScript!
      txb.addOutput(regtestUtils.RANDOM_ADDRESS, 2e4)
      txb.sign(0, keyPair, null, null, 5e4, p2wsh.redeem.output) // NOTE: provide a witnessScript!
      const tx = txb.build()

      // build and broadcast (the P2WSH transaction) to the Bitcoin RegTest network
      regtestUtils.broadcast(tx.toHex(), function (err) {
        if (err) return done(err)

        regtestUtils.verify({
          txId: tx.getId(),
          address: regtestUtils.RANDOM_ADDRESS,
          vout: 0,
          value: 2e4
        }, done)
      })
    })
  })

  it('can create (and broadcast via 3PBP) a Transaction, w/ a P2SH(P2WSH(P2MS(3 of 4))) (SegWit multisig) input', function (done) {
    const keyPairs = [
      bitcoin.ECPair.makeRandom({ network: regtest }),
      bitcoin.ECPair.makeRandom({ network: regtest }),
      bitcoin.ECPair.makeRandom({ network: regtest }),
      bitcoin.ECPair.makeRandom({ network: regtest })
    ]
    const pubkeys = keyPairs.map(x => x.publicKey)

    const p2ms = bitcoin.payments.p2ms({ m: 3, pubkeys, network: regtest })
    const p2wsh = bitcoin.payments.p2wsh({ redeem: p2ms, network: regtest })
    const p2sh = bitcoin.payments.p2sh({ redeem: p2wsh, network: regtest })

    regtestUtils.faucet(p2sh.address, 6e4, function (err, unspent) {
      if (err) return done(err)

      const txb = new bitcoin.TransactionBuilder(regtest)
      txb.addInput(unspent.txId, unspent.vout, null, p2sh.output)
      txb.addOutput(regtestUtils.RANDOM_ADDRESS, 3e4)
      txb.sign(0, keyPairs[0], p2sh.redeem.output, null, unspent.value, p2wsh.redeem.output)
      txb.sign(0, keyPairs[2], p2sh.redeem.output, null, unspent.value, p2wsh.redeem.output)
      txb.sign(0, keyPairs[3], p2sh.redeem.output, null, unspent.value, p2wsh.redeem.output)

      const tx = txb.build()

      // build and broadcast to the Bitcoin RegTest network
      regtestUtils.broadcast(tx.toHex(), function (err) {
        if (err) return done(err)

        regtestUtils.verify({
          txId: tx.getId(),
          address: regtestUtils.RANDOM_ADDRESS,
          vout: 0,
          value: 3e4
        }, done)
      })
    })
  })

  it('can verify Transaction signatures', function () {
    const txHex = '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'
    const keyPairs = [
      '032b4c06c06c3ec0b7fa29519dfa5aae193ee2cc35ca127f29f14ec605d62fb63d',
      '0216c92abe433106491bdeb4a261226f20f5a4ac86220cc6e37655aac6bf3c1f2a',
      '039e05da8b8ea4f9868ecebb25998c7701542986233f4401799551fbecf316b18f'
    ].map(function (q) { return bitcoin.ECPair.fromPublicKey(Buffer.from(q, 'hex')) })

    const tx = bitcoin.Transaction.fromHex(txHex)

    tx.ins.forEach(function (input, i) {
      const keyPair = keyPairs[i]
      const p2pkh = bitcoin.payments.p2pkh({
        pubkey: keyPair.publicKey,
        input: input.script
      })

      const ss = bitcoin.script.signature.decode(p2pkh.signature)
      const hash = tx.hashForSignature(i, p2pkh.output, ss.hashType)

      assert.strictEqual(keyPair.verify(hash, ss.signature), true)
    })
  })
})