/*
  Unit tests for the Memo set-name behavior slice (src/services/memo-set-name.js).

  These tests express the observable behavior described by specs/set-name.feature:
    - a valid name broadcasts an OP_RETURN transaction carrying the Memo set-name
      prefix (0x6d01) and the name text, and the profile store reflects the new
      name.
    - an empty name is rejected with a validation error and nothing is broadcast.
    - an over-long name is rejected with a length error and nothing is broadcast.
*/

'use strict'

const test = require('node:test')
const assert = require('node:assert/strict')

const MemoSetName = require('../../src/services/memo-set-name')

// A fake wallet that records every broadcast attempt. It satisfies the small
// adapter surface the MemoSetName module needs: walletInfo, getUtxos(),
// sendOpReturn().
function fakeWallet (cashAddress = 'bitcoincash:qqlrzp23w08434twmvr4fxw672whkjy0py26r63g3d', utxos = [{ txid: 'utxo1' }]) {
  const broadcasts = []
  const wallet = {
    walletInfo: { cashAddress },
    getUtxos: async () => utxos,
    sendOpReturn: async (msg, prefix) => {
      broadcasts.push({ msg, prefix })
      return 'fake-txid'
    }
  }
  wallet.broadcasts = broadcasts
  return wallet
}

// A fake profile store that records names set for addresses.
function fakeProfiles () {
  const names = {}
  return {
    names,
    setName: (addr, name) => { names[addr] = name },
    getName: (addr) => names[addr] || null
  }
}

test('MEMO_SET_NAME_PREFIX is the Memo set-name action 0x6d01', () => {
  assert.equal(MemoSetName.MEMO_SET_NAME_PREFIX, '6d01')
})

test('setting a valid name broadcasts an OP_RETURN with the Memo set-name prefix and name', async () => {
  const wallet = fakeWallet()
  const profiles = fakeProfiles()
  const memoSetName = new MemoSetName({ wallet, profiles })

  const txid = await memoSetName.setName('trout')

  assert.equal(txid, 'fake-txid')
  assert.equal(wallet.broadcasts.length, 1)
  const b = wallet.broadcasts[0]
  assert.equal(b.prefix, '6d01')
  assert.equal(b.msg, 'trout')

  // The profile store reflects the new name for this address.
  assert.equal(profiles.getName(wallet.walletInfo.cashAddress), 'trout')
})

test('setting a name at the maximum byte length (77) is accepted', async () => {
  const wallet = fakeWallet()
  const memoSetName = new MemoSetName({ wallet })

  const name = 'x'.repeat(77)
  const txid = await memoSetName.setName(name)
  assert.equal(txid, 'fake-txid')
  assert.equal(wallet.broadcasts[0].msg, name)
})

test('setting a name at the maximum byte length with multi-byte characters is accepted', async () => {
  const wallet = fakeWallet()
  const memoSetName = new MemoSetName({ wallet })

  // 38 'é' characters are 76 bytes in UTF-8.
  const name = 'é'.repeat(38)
  assert.equal(Buffer.byteLength(name, 'utf8'), 76)
  const txid = await memoSetName.setName(name)
  assert.equal(txid, 'fake-txid')
})

test('setting an over-long name in bytes (78) throws a length error even when char count is lower', async () => {
  const wallet = fakeWallet()
  const memoSetName = new MemoSetName({ wallet })

  // 40 'é' characters are 80 bytes, exceeding the 77-byte limit.
  const name = 'é'.repeat(40)
  assert.ok(Buffer.byteLength(name, 'utf8') > 77)
  await assert.rejects(
    memoSetName.setName(name),
    (err) => err.code === 'name_length'
  )
  assert.equal(wallet.broadcasts.length, 0)
})

test('setting an empty name throws a validation error and broadcasts nothing', async () => {
  const wallet = fakeWallet()
  const profiles = fakeProfiles()
  const memoSetName = new MemoSetName({ wallet, profiles })

  await assert.rejects(
    memoSetName.setName(''),
    (err) => err.code === 'name_validation'
  )
  assert.equal(wallet.broadcasts.length, 0)
  assert.equal(profiles.getName(wallet.walletInfo.cashAddress), null)
})

test('setting a whitespace-only or non-string name throws a validation error and broadcasts nothing', async () => {
  for (const invalid of ['   ', 42]) {
    const wallet = fakeWallet()
    const memoSetName = new MemoSetName({ wallet })

    await assert.rejects(
      memoSetName.setName(invalid),
      (err) => err.code === 'name_validation'
    )
    assert.equal(wallet.broadcasts.length, 0)
  }
})

test('setting an over-long name (78) throws a length error and broadcasts nothing', async () => {
  const wallet = fakeWallet()
  const profiles = fakeProfiles()
  const memoSetName = new MemoSetName({ wallet, profiles })

  await assert.rejects(
    memoSetName.setName('y'.repeat(78)),
    (err) => err.code === 'name_length'
  )
  assert.equal(wallet.broadcasts.length, 0)
  assert.equal(profiles.getName(wallet.walletInfo.cashAddress), null)
})

test('setting a name without a wallet reports a missing-wallet error', async () => {
  const memoSetName = new MemoSetName({})
  await assert.rejects(
    memoSetName.setName('trout'),
    (err) => /wallet/i.test(err.message)
  )
})

test('a failed broadcast does not update the profile store', async () => {
  const wallet = fakeWallet()
  wallet.sendOpReturn = async () => { throw new Error('broadcast failure') }
  const profiles = fakeProfiles()
  const memoSetName = new MemoSetName({ wallet, profiles })

  await assert.rejects(
    memoSetName.setName('trout'),
    (err) => /broadcast failure/i.test(err.message)
  )
  assert.equal(wallet.broadcasts.length, 0)
  assert.equal(profiles.getName(wallet.walletInfo.cashAddress), null)
})