import { describe, it, expect, vi, beforeEach } from 'vitest'
import type { SupabaseClient } from '@supabase/supabase-js'
import {
  matchSupplierByIdentity,
  matchSupplierId,
  supplierIdentityFrom,
  vatNumberKey,
  vatNumbersMatch,
} from '../match-supplier'

/**
 * Minimal suppliers-table stub. The matcher issues three shapes of query and
 * they are distinguishable by terminator: org_number and name end in
 * maybeSingle(), the vat_number scan ends in range() and is awaited directly.
 */
function makeSupabase(rows: {
  byOrgNumber?: { id: string } | null
  byName?: { id: string } | null
  withVatNumber?: { id: string; vat_number: string | null }[]
  vatScanError?: { message: string }
}) {
  const calls: { column: string; value: unknown }[] = []

  const chain = (): Record<string, unknown> => {
    const self: Record<string, unknown> = {}
    self.select = () => self
    self.eq = (column: string, value: unknown) => {
      if (column !== 'company_id') calls.push({ column, value })
      return self
    }
    self.ilike = (column: string, value: unknown) => {
      calls.push({ column: `ilike:${column}`, value })
      return self
    }
    self.not = () => self
    self.order = () => self
    self.limit = () => self
    self.maybeSingle = () => {
      const last = calls[calls.length - 1]
      if (last?.column === 'org_number') {
        return Promise.resolve({ data: rows.byOrgNumber ?? null, error: null })
      }
      return Promise.resolve({ data: rows.byName ?? null, error: null })
    }
    // The vat_number scan goes through fetchAllRows, which awaits .range().
    self.range = () =>
      Promise.resolve(
        rows.vatScanError
          ? { data: null, error: rows.vatScanError }
          : { data: rows.withVatNumber ?? [], error: null },
      )
    return self
  }

  return {
    supabase: { from: () => chain() } as unknown as SupabaseClient,
    calls,
  }
}

describe('vatNumberKey', () => {
  it('strips formatting and uppercases', () => {
    expect(vatNumberKey('se 556012-5790 01')).toBe('SE556012579001')
    expect(vatNumberKey('IE6364992H')).toBe('IE6364992H')
  })

  it('rejects values too short to identify anything', () => {
    expect(vatNumberKey('SE')).toBeNull()
    expect(vatNumberKey('-')).toBeNull()
    expect(vatNumberKey('')).toBeNull()
    expect(vatNumberKey(null)).toBeNull()
    expect(vatNumberKey(undefined)).toBeNull()
  })
})

describe('vatNumbersMatch', () => {
  it('matches across formatting variants', () => {
    expect(vatNumbersMatch('IE 6364992 H', 'ie6364992h')).toBe(true)
  })

  it('matches when only one side carries the country prefix', () => {
    expect(vatNumbersMatch('SE556012579001', '556012579001')).toBe(true)
    expect(vatNumbersMatch('556012579001', 'SE556012579001')).toBe(true)
  })

  it('keeps different countries distinct', () => {
    expect(vatNumbersMatch('IE6364992H', 'SE6364992H')).toBe(false)
  })

  it('never matches on a missing value', () => {
    expect(vatNumbersMatch(null, 'IE6364992H')).toBe(false)
    expect(vatNumbersMatch('IE6364992H', null)).toBe(false)
    expect(vatNumbersMatch(null, null)).toBe(false)
  })
})

describe('supplierIdentityFrom', () => {
  it('reads the extraction schema shape', () => {
    expect(
      supplierIdentityFrom({
        name: 'Adobe Systems Software Ireland Ltd',
        orgNumber: null,
        vatNumber: 'IE6364992H',
      }),
    ).toEqual({
      name: 'Adobe Systems Software Ireland Ltd',
      orgNumber: null,
      vatNumber: 'IE6364992H',
    })
  })

  it('accepts the legacy organizationNumber spelling', () => {
    expect(supplierIdentityFrom({ organizationNumber: '5566778899' }).orgNumber).toBe('5566778899')
  })

  it('treats blank strings and non-strings as absent', () => {
    expect(supplierIdentityFrom({ name: '  ', vatNumber: 42 })).toEqual({
      name: null,
      orgNumber: null,
      vatNumber: null,
    })
    expect(supplierIdentityFrom(null)).toEqual({ name: null, orgNumber: null, vatNumber: null })
  })
})

describe('matchSupplierByIdentity', () => {
  beforeEach(() => {
    vi.clearAllMocks()
  })

  it('prefers org_number over everything else', async () => {
    const { supabase } = makeSupabase({
      byOrgNumber: { id: 'by-org' },
      withVatNumber: [{ id: 'by-vat', vat_number: 'SE556012579001' }],
      byName: { id: 'by-name' },
    })
    const match = await matchSupplierByIdentity(supabase, 'company-1', {
      orgNumber: '5566778899',
      vatNumber: 'SE556012579001',
      name: 'Acme AB',
    })
    expect(match).toEqual({ supplierId: 'by-org', matchedOn: 'org_number' })
  })

  it('falls back to vat_number when there is no org number: the Adobe case', async () => {
    const { supabase } = makeSupabase({
      byOrgNumber: null,
      withVatNumber: [
        { id: 'other', vat_number: 'DE123456789' },
        { id: 'adobe', vat_number: 'IE6364992H' },
      ],
      byName: null,
    })
    const match = await matchSupplierByIdentity(supabase, 'company-1', {
      orgNumber: null,
      vatNumber: 'IE6364992H',
      name: 'Adobe Systems Software Ireland Ltd',
    })
    expect(match).toEqual({ supplierId: 'adobe', matchedOn: 'vat_number' })
  })

  it('falls through to name when no identifier matches', async () => {
    const { supabase, calls } = makeSupabase({
      byOrgNumber: null,
      withVatNumber: [{ id: 'other', vat_number: 'DE123456789' }],
      byName: { id: 'by-name' },
    })
    const match = await matchSupplierByIdentity(supabase, 'company-1', {
      orgNumber: null,
      vatNumber: 'IE6364992H',
      name: 'Adobe Systems Software Ireland Ltd',
    })
    expect(match).toEqual({ supplierId: 'by-name', matchedOn: 'name' })
    expect(calls.some((c) => c.column === 'ilike:name')).toBe(true)
  })

  it('escapes LIKE metacharacters in the name lookup', async () => {
    const { supabase, calls } = makeSupabase({ byName: { id: 'by-name' } })
    await matchSupplierByIdentity(supabase, 'company-1', { name: '100 % Solutions_AB' })
    const nameCall = calls.find((c) => c.column === 'ilike:name')
    expect(nameCall?.value).toBe('100 \\% Solutions\\_AB')
  })

  it('returns null when nothing matches', async () => {
    const { supabase } = makeSupabase({ byOrgNumber: null, withVatNumber: [], byName: null })
    const match = await matchSupplierByIdentity(supabase, 'company-1', {
      orgNumber: null,
      vatNumber: 'IE6364992H',
      name: 'Unknown Ltd',
    })
    expect(match).toBeNull()
  })

  it('skips lookups entirely for an empty identity', async () => {
    const { supabase, calls } = makeSupabase({})
    const match = await matchSupplierByIdentity(supabase, 'company-1', {
      orgNumber: null,
      vatNumber: null,
      name: null,
    })
    expect(match).toBeNull()
    expect(calls).toEqual([])
  })

  it('falls through to name when the vat_number scan fails', async () => {
    const consoleSpy = vi.spyOn(console, 'error').mockImplementation(() => {})
    const { supabase } = makeSupabase({
      byOrgNumber: null,
      vatScanError: { message: 'connection reset' },
      byName: { id: 'by-name' },
    })
    const match = await matchSupplierByIdentity(supabase, 'company-1', {
      vatNumber: 'IE6364992H',
      name: 'Adobe Systems Software Ireland Ltd',
    })
    expect(match).toEqual({ supplierId: 'by-name', matchedOn: 'name' })
    consoleSpy.mockRestore()
  })
})

describe('matchSupplierId', () => {
  it('returns just the id', async () => {
    const { supabase } = makeSupabase({ byOrgNumber: { id: 'by-org' } })
    await expect(
      matchSupplierId(supabase, 'company-1', { orgNumber: '5566778899' }),
    ).resolves.toBe('by-org')
  })

  it('returns null when unmatched', async () => {
    const { supabase } = makeSupabase({ byName: null })
    await expect(matchSupplierId(supabase, 'company-1', { name: 'Nope' })).resolves.toBeNull()
  })
})