import { describe, expect, it } from 'vitest';
import { tenderFingerprint, valueBucketsContradict } from './tender-fingerprint';

/**
 * SCHEMA-03 (D-04) — pure fingerprint function, v2 formula (WINDOWS.md #11).
 * v2 hashes only [buyerName, title, deadlineAt]. CPV and estimatedValue are
 * NOT hash inputs anymore — see the file comment on tender-fingerprint.ts
 * for why and for the three limits this plan deliberately leaves in place.
 */
describe('tenderFingerprint', () => {
  it('is the Kernregression this plan exists for: a DOE-shaped record and a scraper-shaped record of the same tender collide', () => {
    const doeShaped = {
      buyerName: 'Stadt München',
      title: 'Neubau einer Kindertagesstätte',
      cpvDivisions: ['45'],
      deadlineAt: new Date('2026-06-01T00:00:00Z'),
      estimatedValue: 387291,
    };
    const scraperShaped = {
      buyerName: 'Stadt München',
      title: 'Neubau einer Kindertagesstätte',
      cpvDivisions: [] as string[],
      deadlineAt: new Date('2026-06-01T00:00:00Z'),
      estimatedValue: null as number | null,
    };
    // Extra fields (cpvDivisions, estimatedValue) prove they can't reach
    // the hash: they're passed straight through as typed variables, the
    // way the resolver calls this function with its wider normalized
    // record — TS excess-property checking only fires on object literals.
    expect(tenderFingerprint(doeShaped)).toBe(tenderFingerprint(scraperShaped));
  });

  it('differs for a different title (collision guard, Pitfall 1)', () => {
    const base = { buyerName: 'Stadt München', title: 'Neubau einer Kindertagesstätte', deadlineAt: null };
    const a = tenderFingerprint(base);
    const b = tenderFingerprint({ ...base, title: 'Sanierung eines Kindergartens' });
    expect(a).not.toBe(b);
  });

  it('normalizes umlauts so "München" and "Muenchen" contribute the same text', () => {
    const base = { title: 'Neubau einer Kindertagesstätte', deadlineAt: null };
    const a = tenderFingerprint({ ...base, buyerName: 'Stadt München' });
    const b = tenderFingerprint({ ...base, buyerName: 'Stadt Muenchen' });
    expect(a).toBe(b);
  });

  it('collapses two deadlines on the same day to the same fingerprint, and separates two different days', () => {
    const base = { buyerName: 'Stadt München', title: 'Neubau einer Kindertagesstätte' };
    const sameDayMorning = tenderFingerprint({ ...base, deadlineAt: new Date('2026-06-01T08:00:00Z') });
    const sameDayEvening = tenderFingerprint({ ...base, deadlineAt: new Date('2026-06-01T20:00:00Z') });
    const otherDay = tenderFingerprint({ ...base, deadlineAt: new Date('2026-06-02T08:00:00Z') });
    expect(sameDayMorning).toBe(sameDayEvening);
    expect(sameDayMorning).not.toBe(otherDay);
  });

  it('treats a null buyerName as an empty segment, not a crash', () => {
    const args = { buyerName: null as string | null, title: 'Neubau einer Kindertagesstätte', deadlineAt: null };
    expect(() => tenderFingerprint(args)).not.toThrow();
    const a = tenderFingerprint(args);
    const b = tenderFingerprint(args);
    expect(a).toBe(b);
  });

  it('returns "v2:" followed by 64 hex characters', () => {
    const result = tenderFingerprint({
      buyerName: 'Stadt München',
      title: 'Neubau einer Kindertagesstätte',
      deadlineAt: null,
    });
    expect(result).toMatch(/^v2:[a-f0-9]{64}$/);
  });

  it('gold value: nails the segment count and order — a fourth (even empty) segment or a reordering turns this red', () => {
    // Hand-computed independently of production code from the canonical
    // string "stadt musterstadt|neubau turnhalle|2026-03-04" — not built
    // with normText/deadlineKey.
    const result = tenderFingerprint({
      buyerName: 'Stadt Musterstadt',
      title: 'Neubau Turnhalle',
      deadlineAt: new Date('2026-03-04T09:00:00Z'),
    });
    expect(result).toBe(
      'v2:6104874e683082d4e656e5585947629dcb8c667eb77888c456020ce86993be34',
    );
  });
});

describe('valueBucketsContradict', () => {
  it('is false when the left side is null', () => {
    expect(valueBucketsContradict(null, 5000)).toBe(false);
  });

  it('is false when the right side is null', () => {
    expect(valueBucketsContradict(5000, null)).toBe(false);
  });

  it('is false when both sides are null', () => {
    expect(valueBucketsContradict(null, null)).toBe(false);
  });

  it('is false for two values of the same order of magnitude', () => {
    expect(valueBucketsContradict(12000, 15000)).toBe(false);
  });

  it('is true for two values across a magnitude boundary', () => {
    expect(valueBucketsContradict(9000, 90000)).toBe(true);
  });
});