import { describe, it, expect } from 'vitest'
import {
  anyAssetHasComponents,
  buildEquityChangesNote,
  buildK3RedovisningsPrinciper,
  buildMateriellaAnlaggningsNot,
  buildUppskjutenSkattNot,
} from '../k3-noter-builder'

describe('buildK3RedovisningsPrinciper', () => {
  it('always includes the K3 framework citation and the standard policy paragraphs', () => {
    const note = buildK3RedovisningsPrinciper(false)
    expect(note.number).toBe(1)
    expect(note.title).toBe('Redovisnings- och värderingsprinciper')
    expect(note.body).toContain('BFNAR 2012:1')
    expect(note.body).toContain('Uppskjuten skatt')
    expect(note.body).toContain('Intäktsredovisning')
    expect(note.body).toContain('Leasing')
    expect(note.body).toContain('Finansiella instrument')
  })

  it('OMITS the komponentavskrivning paragraph when no asset has components', () => {
    const note = buildK3RedovisningsPrinciper(false)
    expect(note.body).not.toMatch(/Komponentavskrivning/)
  })

  it('INCLUDES the komponentavskrivning paragraph when an asset has components', () => {
    const note = buildK3RedovisningsPrinciper(true)
    expect(note.body).toMatch(/Komponentavskrivning/)
    expect(note.body).toMatch(/betydande komponenter/)
  })
})

describe('buildUppskjutenSkattNot', () => {
  it('renders opening + change + closing line in the body', () => {
    const note = buildUppskjutenSkattNot({
      noteNumber: 4,
      latentTaxOpening: 50_000,
      latentTaxChange: 20_600,
      latentTaxClosing: 70_600,
    })
    expect(note.number).toBe(4)
    expect(note.title).toBe('Uppskjutna skatter')
    // sv-SE thousand separator uses non-breaking space (\u00A0)
    expect(note.body).toMatch(/Ingående saldo.*50/)
    expect(note.body).toMatch(/Årets förändring.*20/)
    expect(note.body).toMatch(/Utgående saldo.*70/)
  })

  it('handles zero values without producing NaN strings', () => {
    const note = buildUppskjutenSkattNot({
      noteNumber: 2,
      latentTaxOpening: 0,
      latentTaxChange: 0,
      latentTaxClosing: 0,
    })
    expect(note.body).not.toMatch(/NaN/)
    expect(note.body).toMatch(/0 kr/)
  })

  it('handles a negative change (återföring)', () => {
    const note = buildUppskjutenSkattNot({
      noteNumber: 3,
      latentTaxOpening: 70_600,
      latentTaxChange: -10_000,
      latentTaxClosing: 60_600,
    })
    // Swedish locale formats negative numbers with the Unicode minus sign
    // (U+2212), not the ASCII hyphen-minus — match either to be robust.
    expect(note.body).toMatch(/[-−]10/)
    expect(note.body).toMatch(/Ingående saldo.*70/)
    expect(note.body).toMatch(/Utgående saldo.*60/)
  })

  it('mentions the 20.6% latent tax rate so readers understand the figures', () => {
    const note = buildUppskjutenSkattNot({
      noteNumber: 1,
      latentTaxOpening: 0,
      latentTaxChange: 0,
      latentTaxClosing: 0,
    })
    expect(note.body).toMatch(/20,6/)
  })
})

describe('buildEquityChangesNote', () => {
  it('reconciles opening + changes to closing total', () => {
    const result = buildEquityChangesNote({
      opening: {
        aktiekapital: 50_000,
        bundna_reserver: 10_000,
        balanserade_vinstmedel: 100_000,
      },
      changes: {
        nyemission: 25_000,
        utdelning: -15_000,
        arets_resultat: 80_000,
      },
    })
    // 50 000 + 10 000 + 100 000 + 25 000 - 15 000 + 80 000 = 250 000
    expect(result.closing_total).toBe(250_000)
  })

  it('emits rows for each opening component plus changes plus closing', () => {
    const result = buildEquityChangesNote({
      opening: {
        aktiekapital: 50_000,
        bundna_reserver: 0,
        balanserade_vinstmedel: 100_000,
      },
      changes: {
        nyemission: 25_000,
        utdelning: -15_000,
        arets_resultat: 80_000,
      },
    })
    const labels = result.rows.map((r) => r.label)
    expect(labels).toContain('Ingående aktiekapital')
    expect(labels).toContain('Ingående balanserade vinstmedel')
    expect(labels).toContain('Nyemission')
    expect(labels).toContain('Utdelning')
    expect(labels).toContain('Årets resultat')
    expect(labels).toContain('Summa utgående eget kapital')
  })

  it('OMITS the nyemission row when no nyemission happened (cleaner statement)', () => {
    const result = buildEquityChangesNote({
      opening: {
        aktiekapital: 50_000,
        bundna_reserver: 0,
        balanserade_vinstmedel: 100_000,
      },
      changes: {
        nyemission: 0,
        utdelning: -15_000,
        arets_resultat: 80_000,
      },
    })
    const labels = result.rows.map((r) => r.label)
    expect(labels).not.toContain('Nyemission')
    // Utdelning + årets resultat still present
    expect(labels).toContain('Utdelning')
    expect(labels).toContain('Årets resultat')
  })

  it('OMITS the utdelning row when no utdelning happened', () => {
    const result = buildEquityChangesNote({
      opening: {
        aktiekapital: 50_000,
        bundna_reserver: 0,
        balanserade_vinstmedel: 100_000,
      },
      changes: {
        nyemission: 0,
        utdelning: 0,
        arets_resultat: 80_000,
      },
    })
    const labels = result.rows.map((r) => r.label)
    expect(labels).not.toContain('Nyemission')
    expect(labels).not.toContain('Utdelning')
    // Årets resultat always shown — even when zero — so the year-end
    // disposition is visible in the statement.
    expect(labels).toContain('Årets resultat')
  })

  it('handles all-zero opening + changes without crashing', () => {
    const result = buildEquityChangesNote({
      opening: { aktiekapital: 0, bundna_reserver: 0, balanserade_vinstmedel: 0 },
      changes: { nyemission: 0, utdelning: 0, arets_resultat: 0 },
    })
    expect(result.closing_total).toBe(0)
    expect(result.rows.length).toBeGreaterThan(0)
  })
})

describe('buildMateriellaAnlaggningsNot', () => {
  it('returns null when there are no tangible assets', () => {
    const note = buildMateriellaAnlaggningsNot({
      noteNumber: 5,
      assets: [],
    })
    expect(note).toBeNull()
  })

  it('returns null when only immaterial assets exist (they belong in a separate note)', () => {
    const note = buildMateriellaAnlaggningsNot({
      noteNumber: 5,
      assets: [
        {
          name: 'Software License',
          category: 'immaterial',
          acquisition_date: '2025-01-01',
          acquisition_cost: 50_000,
          k3_components: null,
          disposed_at: null,
          useful_life_months: 60,
        },
      ],
    })
    expect(note).toBeNull()
  })

  it('emits the avskrivningstider summary for tangible assets without components', () => {
    const note = buildMateriellaAnlaggningsNot({
      noteNumber: 3,
      assets: [
        {
          name: 'Macbook Pro',
          category: 'computer',
          acquisition_date: '2025-01-01',
          acquisition_cost: 30_000,
          k3_components: null,
          disposed_at: null,
          useful_life_months: 36, // 3 år
        },
        {
          name: 'Skrivbord',
          category: 'equipment',
          acquisition_date: '2025-01-01',
          acquisition_cost: 5_000,
          k3_components: null,
          disposed_at: null,
          useful_life_months: 60, // 5 år
        },
      ],
    })
    expect(note).not.toBeNull()
    expect(note!.title).toBe('Materiella anläggningstillgångar')
    expect(note!.body).toMatch(/Datorer: 3 år/)
    expect(note!.body).toMatch(/Inventarier: 5 år/)
    // Should NOT mention komponentuppdelning since no components were given
    expect(note!.body).not.toMatch(/Komponentuppdelning/)
  })

  it('renders per-component sub-totals when an asset has K3 components', () => {
    const note = buildMateriellaAnlaggningsNot({
      noteNumber: 3,
      assets: [
        {
          name: 'Lokalbyggnad Sjövägen 12',
          category: 'building',
          acquisition_date: '2020-01-01',
          acquisition_cost: 5_000_000,
          k3_components: [
            {
              name: 'Stomme',
              acquisition_cost: 3_000_000,
              accumulated_depreciation: 300_000,
              useful_life_months: 600, // 50 år
            },
            {
              name: 'Tak',
              acquisition_cost: 800_000,
              accumulated_depreciation: 200_000,
              useful_life_months: 360, // 30 år
            },
            {
              name: 'Installationer',
              acquisition_cost: 1_200_000,
              accumulated_depreciation: 600_000,
              useful_life_months: 240, // 20 år
            },
          ],
          disposed_at: null,
          useful_life_months: 600,
        },
      ],
    })
    expect(note).not.toBeNull()
    expect(note!.body).toMatch(/Komponentuppdelning/)
    expect(note!.body).toMatch(/Stomme/)
    expect(note!.body).toMatch(/Tak/)
    expect(note!.body).toMatch(/Installationer/)
    // Per-component totals must reconcile: 3,000,000 + 800,000 + 1,200,000 = 5,000,000
    // Look for the summary line
    expect(note!.body).toMatch(/Summa:/)
    // Total acquisition cost text (with sv-SE separator)
    // Just confirm 5 000 000 appears as a sub-total somewhere
    expect(note!.body).toMatch(/5\s?000\s?000/)
  })

  it('skips disposed assets in the calculation', () => {
    const note = buildMateriellaAnlaggningsNot({
      noteNumber: 3,
      assets: [
        {
          name: 'Old Macbook',
          category: 'computer',
          acquisition_date: '2020-01-01',
          acquisition_cost: 20_000,
          k3_components: null,
          disposed_at: '2025-06-01',
          useful_life_months: 36,
        },
      ],
    })
    expect(note).toBeNull()
  })
})

describe('anyAssetHasComponents', () => {
  it('returns false for empty array', () => {
    expect(anyAssetHasComponents([])).toBe(false)
  })

  it('returns false when no asset has a components array', () => {
    expect(
      anyAssetHasComponents([
        {
          name: 'X',
          category: 'computer',
          acquisition_date: '2025-01-01',
          acquisition_cost: 1000,
          k3_components: null,
          disposed_at: null,
          useful_life_months: 36,
        },
      ]),
    ).toBe(false)
  })

  it('returns true when at least one asset has a valid components array', () => {
    expect(
      anyAssetHasComponents([
        {
          name: 'Y',
          category: 'building',
          acquisition_date: '2025-01-01',
          acquisition_cost: 1_000_000,
          k3_components: [
            {
              name: 'Stomme',
              acquisition_cost: 800_000,
              accumulated_depreciation: 0,
              useful_life_months: 600,
            },
          ],
          disposed_at: null,
          useful_life_months: 600,
        },
      ]),
    ).toBe(true)
  })

  it('ignores disposed assets when checking for components', () => {
    expect(
      anyAssetHasComponents([
        {
          name: 'Sold Building',
          category: 'building',
          acquisition_date: '2020-01-01',
          acquisition_cost: 1_000_000,
          k3_components: [
            {
              name: 'Stomme',
              acquisition_cost: 800_000,
              accumulated_depreciation: 0,
              useful_life_months: 600,
            },
          ],
          disposed_at: '2025-06-01',
          useful_life_months: 600,
        },
      ]),
    ).toBe(false)
  })

  it('rejects malformed component payloads (typeguard)', () => {
    expect(
      anyAssetHasComponents([
        {
          name: 'Bad data',
          category: 'building',
          acquisition_date: '2025-01-01',
          acquisition_cost: 1_000_000,
          // Missing required fields
          k3_components: [{ name: 'Stomme' }],
          disposed_at: null,
          useful_life_months: 600,
        },
      ]),
    ).toBe(false)
  })
})