import { describe, it, expect, vi, afterEach } from 'vitest'
import { fetchLightningStrikes, projectStrikeToLayer } from '../../../src/lib/api/lightning.js'

afterEach(() => {
  vi.restoreAllMocks()
})

describe('fetchLightningStrikes', () => {
  it('builds the relay URL with lat/lon/radius/limit', async () => {
    const fetchMock = vi.fn().mockResolvedValue({
      ok: true,
      json: async () => ({ source: 'blitzortung', strikes: [] }),
    })
    globalThis.fetch = fetchMock

    await fetchLightningStrikes({ lat: 36.35, lon: -95.81, radiusKm: 100, limit: 50 })

    const [url] = fetchMock.mock.calls[0]
    expect(url).toContain('https://cors.thecookiejar.me/lightning?')
    expect(url).toContain('lat=36.35')
    expect(url).toContain('lon=-95.81')
    expect(url).toContain('radiusKm=100')
    expect(url).toContain('limit=50')
  })

  it('returns the strike list on a valid response', async () => {
    globalThis.fetch = vi.fn().mockResolvedValue({
      ok: true,
      json: async () => ({
        source: 'blitzortung',
        strikes: [
          { lat: 36.3, lon: -95.8, time: 1724671234, strength: -12 },
          { lat: 36.5, lon: -95.9, time: 1724671299 },
        ],
      }),
    })

    const strikes = await fetchLightningStrikes({ lat: 36.35, lon: -95.81 })
    expect(strikes).toHaveLength(2)
    expect(strikes[0]).toMatchObject({ lat: 36.3, lon: -95.8, strength: -12 })
  })

  it('throws on a non-OK relay response', async () => {
    globalThis.fetch = vi.fn().mockResolvedValue({ ok: false, status: 502, statusText: 'Bad Gateway' })
    await expect(fetchLightningStrikes({ lat: 0, lon: 0 })).rejects.toThrow(/Lightning relay error: 502/)
  })

  it('throws on a malformed response (no strikes array)', async () => {
    globalThis.fetch = vi.fn().mockResolvedValue({ ok: true, json: async () => ({ foo: 1 }) })
    await expect(fetchLightningStrikes({ lat: 0, lon: 0 })).rejects.toThrow(/invalid response/)
  })

  it('throws when the relay is unreachable (network failure)', async () => {
    globalThis.fetch = vi.fn().mockRejectedValue(new TypeError('Failed to fetch'))
    await expect(fetchLightningStrikes({ lat: 0, lon: 0 })).rejects.toThrow()
  })
})

describe('projectStrikeToLayer', () => {
  // Center tile is (0.5, 0.5) at zoom 0 (lon=0,lat=0). A strike exactly at the
  // location should land at the center of the 5x5 layer: (2.5, 2.5) tiles.
  it('maps a strike at the center location to the layer center', () => {
    const { x, y } = projectStrikeToLayer(0, 0, { zoom: 0, cx: 0.5, cy: 0.5, tileSize: 256 })
    expect(x).toBeCloseTo(640)
    expect(y).toBeCloseTo(640)
  })

  it('scales with tile size', () => {
    const { x } = projectStrikeToLayer(0, 0, { zoom: 0, cx: 0.5, cy: 0.5, tileSize: 128 })
    expect(x).toBeCloseTo(320)
  })

  it('moves the strike right as lon increases', () => {
    const a = projectStrikeToLayer(0, 1, { zoom: 0, cx: 0.5, cy: 0.5, tileSize: 256 })
    const b = projectStrikeToLayer(0, 5, { zoom: 0, cx: 0.5, cy: 0.5, tileSize: 256 })
    expect(a.x).toBeGreaterThan(640)
    expect(b.x).toBeGreaterThan(a.x)
  })
})