import { describe, expect, it } from 'vitest'
import { findConflicts, wouldConflict } from '@/lib/timetable/conflict'
import { ArtistEngagementStatus, type Performance } from '@/types/timetable'

function p(overrides: Partial<Performance> = {}): Performance {
  return {
    id: 'p1',
    engagement_id: 'e1',
    event_id: 'ev1',
    stage_id: 's1',
    lane: 0,
    lane_resolved: 0,
    start_at: '2026-07-10T18:00:00.000Z',
    end_at: '2026-07-10T19:00:00.000Z',
    version: 0,
    notes: null,
    warnings: [],
    created_at: null,
    updated_at: null,
    deleted_at: null,
    ...overrides,
  }
}

describe('findConflicts', () => {
  it('flags two overlapping performances on the same lane', () => {
    const conflicts = findConflicts([
      p({ id: 'a', start_at: '2026-07-10T18:00:00Z', end_at: '2026-07-10T19:00:00Z' }),
      p({ id: 'b', start_at: '2026-07-10T18:30:00Z', end_at: '2026-07-10T19:30:00Z' }),
    ])

    expect(conflicts).toEqual(new Set(['a', 'b']))
  })

  it('endpoint-touching is NOT overlap', () => {
    const conflicts = findConflicts([
      p({ id: 'a', start_at: '2026-07-10T18:00:00Z', end_at: '2026-07-10T19:00:00Z' }),
      p({ id: 'b', start_at: '2026-07-10T19:00:00Z', end_at: '2026-07-10T20:00:00Z' }),
    ])

    expect(conflicts.size).toBe(0)
  })

  it('different lanes on same stage = no conflict', () => {
    const conflicts = findConflicts([
      p({ id: 'a', lane_resolved: 0 }),
      p({ id: 'b', lane_resolved: 1 }),
    ])

    expect(conflicts.size).toBe(0)
  })

  it('different stages = no conflict', () => {
    const conflicts = findConflicts([
      p({ id: 'a', stage_id: 's1' }),
      p({ id: 'b', stage_id: 's2' }),
    ])

    expect(conflicts.size).toBe(0)
  })

  it('cancelled performances do not participate', () => {
    const cancelled = p({
      id: 'c',
      engagement: {
        booking_status: { value: ArtistEngagementStatus.CANCELLED, label: 'Geannuleerd' },
      } as Performance['engagement'],
    })

    const conflicts = findConflicts([
      p({ id: 'a' }),
      cancelled,
    ])

    expect(conflicts.size).toBe(0)
  })

  it('parked performances (stage_id null) do not participate', () => {
    const conflicts = findConflicts([
      p({ id: 'a', stage_id: null }),
      p({ id: 'b' }),
    ])

    expect(conflicts.size).toBe(0)
  })
})

describe('wouldConflict', () => {
  it('detects 1-pixel overlap', () => {
    const others = [p({ id: 'x', start_at: '2026-07-10T18:00:00Z', end_at: '2026-07-10T19:00:00Z' })]

    const result = wouldConflict({
      id: 'new',
      stage_id: 's1',
      lane: 0,
      start_at: '2026-07-10T18:59:00Z',
      end_at: '2026-07-10T20:00:00Z',
    }, others)

    expect(result).toBe(true)
  })

  it('returns false when candidate is parked', () => {
    const others = [p({ id: 'x' })]

    const result = wouldConflict({
      id: 'new',
      stage_id: null,
      lane: 0,
      start_at: '2026-07-10T18:00:00Z',
      end_at: '2026-07-10T19:00:00Z',
    }, others)

    expect(result).toBe(false)
  })
})