// SPDX-FileCopyrightText: © 2026 LEDGER SAS
// SPDX-License-Identifier: Apache-2.0

import * as network from '../network'
import { getBlockInfo } from './getBlockInfo'

jest.mock('../network', () => ({
  ...jest.requireActual<typeof import('../network')>('../network'),
  fetchLedgerRecord: jest.fn(),
}))

const fetchLedgerRecordMock = network.fetchLedgerRecord as jest.MockedFunction<
  typeof network.fetchLedgerRecord
>

describe('getBlockInfo', () => {
  beforeEach(() => {
    jest.clearAllMocks()
  })

  it('returns block info with parent when height > 1 (uses ledger prev_hash)', async () => {
    fetchLedgerRecordMock.mockImplementation(
      async (seq: number) =>
        ({
          sequence: seq,
          hash: `hash-${seq}`,
          closed_at: `2020-01-0${seq}T00:00:00Z`,
          ...(seq > 1 && { prev_hash: `hash-${seq - 1}` }),
        }) as unknown as Awaited<ReturnType<typeof network.fetchLedgerRecord>>
    )

    const result = await getBlockInfo(5)

    expect(fetchLedgerRecordMock).toHaveBeenCalledTimes(1)
    expect(fetchLedgerRecordMock).toHaveBeenCalledWith(5)
    expect(result).toEqual({
      height: 5,
      hash: 'hash-5',
      time: new Date('2020-01-05T00:00:00Z'),
      parent: { height: 4, hash: 'hash-4' },
    })
  })

  it('falls back to fetching parent ledger when prev_hash is missing', async () => {
    fetchLedgerRecordMock.mockImplementation(
      async (seq: number) =>
        ({
          sequence: seq,
          hash: `hash-${seq}`,
          closed_at: `2020-01-0${seq}T00:00:00Z`,
        }) as unknown as Awaited<ReturnType<typeof network.fetchLedgerRecord>>
    )

    const result = await getBlockInfo(5)

    expect(fetchLedgerRecordMock).toHaveBeenCalledWith(5)
    expect(fetchLedgerRecordMock).toHaveBeenCalledWith(4)
    expect(fetchLedgerRecordMock).toHaveBeenCalledTimes(2)
    expect(result).toEqual({
      height: 5,
      hash: 'hash-5',
      time: new Date('2020-01-05T00:00:00Z'),
      parent: { height: 4, hash: 'hash-4' },
    })
  })

  it('omits parent for genesis ledger sequence 1', async () => {
    fetchLedgerRecordMock.mockResolvedValue({
      sequence: 1,
      hash: 'genesis-hash',
      closed_at: '2015-09-30T00:00:00Z',
    } as unknown as Awaited<ReturnType<typeof network.fetchLedgerRecord>>)

    const result = await getBlockInfo(1)

    expect(fetchLedgerRecordMock).toHaveBeenCalledTimes(1)
    expect(fetchLedgerRecordMock).toHaveBeenCalledWith(1)
    expect(result.parent).toBeUndefined()
    expect(result.height).toBe(1)
  })

  describe('height validation', () => {
    it('rejects height 0', async () => {
      await expect(getBlockInfo(0)).rejects.toThrow(
        'getBlockInfo: height must be a positive integer, got 0'
      )
    })

    it('rejects negative height', async () => {
      await expect(getBlockInfo(-3)).rejects.toThrow(
        'getBlockInfo: height must be a positive integer, got -3'
      )
    })

    it('rejects non-integer height', async () => {
      await expect(getBlockInfo(3.5)).rejects.toThrow(
        'getBlockInfo: height must be a positive integer, got 3.5'
      )
    })

    it('rejects NaN', async () => {
      await expect(getBlockInfo(Number.NaN)).rejects.toThrow(
        'getBlockInfo: height must be a positive integer, got NaN'
      )
    })

    it('rejects unsafe integer', async () => {
      await expect(getBlockInfo(Number.MAX_SAFE_INTEGER + 1)).rejects.toThrow(
        'getBlockInfo: height must be a positive integer'
      )
    })

    it('rejects Infinity', async () => {
      await expect(getBlockInfo(Number.POSITIVE_INFINITY)).rejects.toThrow(
        'getBlockInfo: height must be a positive integer, got Infinity'
      )
    })
  })
})