import { describe, expect, it } from 'vitest';
import { defaultState, fireplace, rectangle } from '../src/lib/defaults';
import { PERSISTENCE_LIMITS, PROJECT_LIMITS } from '../src/lib/limits';
import { decodeState, encodeState } from '../src/lib/url-state';

function expectInvalid(link: string, message?: RegExp) {
  const result = decodeState(link);
  expect(result.state).toEqual(defaultState());
  expect(result.error).toMatch(message ?? /Could not load this plan/);
}

describe('URL state', () => {
  it('starts with independent defaults when no link is provided', () => {
    for (const link of ['', '#', '?']) {
      const first = decodeState(link);
      expect(first).toEqual({ state: defaultState(), error: null });
      first.state.project.rooms[0].name = 'Edited';
      expect(decodeState(link).state.project.rooms[0].name).toBe('Living room');
    }
  });

  it('round-trips current inputs exactly and produces a stable readable link', () => {
    const state = defaultState();
    const query = encodeState(state);
    expect(query).toMatch(/^\?version=2&name=/);
    const params = new URLSearchParams(query);
    expect(params.get('flooring.length')).toBe('1200');
    expect(params.get('flooring.optimisation')).toBe('cuts');
    expect(params.get('skirting.length')).toBe('2400');
    expect(params.get('room.1.wall.1.length')).toBe('4800');
    expect(params.get('room.1.wall.4.door.1.width')).toBe('826');
    expect(query).not.toContain('#plan=');
    expect(decodeState(query)).toEqual({ state, error: null });
    expect(encodeState(decodeState(query).state)).toBe(query);
    expect(encodeState(structuredClone(state))).toBe(query);
  });

  it('round-trips Unicode, rooms, doors, materials, progress and view selections', () => {
    const state = defaultState();
    state.project.name = 'Zoë’s 家 🏡 – mõõtmised';
    state.project.rooms.push(fireplace('room-2', 'Slaapkamer 北'));
    state.project.rooms[1].direction = 90;
    state.project.rooms[0].walls[0].doors = [{ id: 'wide-door', offset: 123.75, width: 1500 }];
    state.project.flooring.pattern = 'random';
    state.project.flooring.optimisation = 'random';
    state.project.skirting.stockLength = 3600;
    state.project.completedBoards = ['floor:B4', 'skirting:S6'];
    state.view = {
      roomId: 'room-2',
      selectedPiece: 'A12',
      search: 'A12',
      collapsedSections: ['materials'],
      material: 'skirting',
    };
    expect(decodeState(encodeState(state))).toEqual({ state, error: null });
  });

  it('canonicalizes property order and discards unknown derived fields', () => {
    const state = defaultState();
    const reordered = {
      view: { ...state.view, derived: 6 },
      project: { ...state.project, boardCount: 500 },
      cache: [],
    };
    expect(encodeState(reordered)).toBe(encodeState(state));
    const params = new URLSearchParams(encodeState(state));
    params.set('boardCount', '500');
    params.set('room.1.polygon', 'derived');
    expect(decodeState(`?${params}`)).toEqual({ state, error: null });
  });

  it('preserves finite domain-invalid measurements for planner feedback', () => {
    const state = defaultState();
    state.project.rooms[0].walls[0].length = -1;
    state.project.rooms[0].walls[0].turn = 999;
    state.project.flooring.width = 0;
    state.project.flooring.minOffset = 1000;
    state.project.flooring.maxOffset = 100;
    state.project.skirting.thickness = -20;
    state.project.tolerance = -1;
    expect(decodeState(encodeState(state))).toEqual({ state, error: null });
  });

  it('allows unfinished current projects without inventing inputs', () => {
    const state = defaultState();
    state.project.rooms[0].walls = [];
    state.project.skirting.stockLength = 0;
    expect(decodeState(encodeState(state))).toEqual({ state, error: null });
  });

  it('falls back to the first room for a stale selected room', () => {
    const params = new URLSearchParams(encodeState(defaultState()));
    params.set('selectedRoom', 'deleted-room');
    const result = decodeState(`?${params}`);
    expect(result.error).toBeNull();
    expect(result.state.view.roomId).toBe(result.state.project.rooms[0].id);
  });

  it.each(['#plan=old', '#other=value', 'version=2'])('rejects non-query links %s', (link) => {
    expectInvalid(link, /starting with \?/);
  });

  it.each(['?version=1', '?version=3'])('rejects unsupported schema link %s', (link) => {
    expectInvalid(link, /version is unsupported/);
  });

  it('requires every field in the current in-memory contract', () => {
    const missingOptimisation = defaultState();
    delete (
      missingOptimisation.project.flooring as Partial<typeof missingOptimisation.project.flooring>
    ).optimisation;
    expect(() => encodeState(missingOptimisation)).toThrow(/optimisation.*unsupported/i);

    const missingStockLength = defaultState();
    delete (
      missingStockLength.project.skirting as Partial<typeof missingStockLength.project.skirting>
    ).stockLength;
    expect(() => encodeState(missingStockLength)).toThrow(/finite number/);
  });

  it('rejects incorrectly typed and nonfinite measurements when reading or writing', () => {
    for (const query of [
      '?flooring.length=NaN',
      '?flooring.length=Infinity',
      '?flooring.length=1e999',
      '?flooring.length=',
      '?flooring.length=true',
      '?flooring.length=0x10',
    ])
      expectInvalid(query, /finite number/);

    const state = defaultState();
    state.project.flooring.length = '1200' as never;
    expect(() => encodeState(state)).toThrow(/finite number/);
    for (const invalid of [NaN, Infinity, -Infinity]) {
      state.project.flooring.length = invalid;
      expect(() => encodeState(state)).toThrow(/finite number/);
    }
  });

  it.each(['?flooring.pattern=diagonal', '?flooring.optimisation=quick', '?room.1.direction=45'])(
    'rejects an invalid current enum in %s',
    (query) => expectInvalid(query),
  );

  it('uses individually editable fields and canonical parameter order', () => {
    const state = defaultState();
    const params = new URLSearchParams(encodeState(state));
    params.set('flooring.length', '1400');
    params.set('flooring.maxOffset', '700');
    params.set('room.1.wall.1.length', '5123.5');
    params.set('room.1.wall.4.door.1.width', '900');
    params.set('skirting.length', '3600');
    params.set('selectedCut', 'F12');
    const result = decodeState(`?${params}`);
    expect(result.error).toBeNull();
    expect(result.state.project.flooring.length).toBe(1400);
    expect(result.state.project.rooms[0].walls[0].length).toBe(5123.5);
    expect(result.state.project.rooms[0].walls[3].doors[0].width).toBe(900);
    expect(result.state.project.skirting.stockLength).toBe(3600);
    expect(result.state.view.selectedPiece).toBe('F12');
    const reversed = new URLSearchParams([...params].reverse());
    expect(encodeState(decodeState(`?${reversed}`).state)).toBe(encodeState(result.state));
  });

  it('accepts a hand-written partial query with current defaults', () => {
    const result = decodeState('?flooring.length=1400&flooring.pattern=random&selectedCut=F2');
    const state = defaultState();
    state.project.flooring.length = 1400;
    state.project.flooring.pattern = 'random';
    state.view.selectedPiece = 'F2';
    expect(result).toEqual({ state, error: null });
  });

  it('can describe an unfinished room without array counts or generated plans', () => {
    const result = decodeState(
      '?room.1.name=Office&room.1.wall.1.length=4000&room.1.wall.1.turn=-90',
    );
    expect(result.error).toBeNull();
    expect(result.state.project.rooms).toEqual([
      {
        id: 'room-1',
        name: 'Office',
        direction: 0,
        walls: [{ id: 'room-1-w1', length: 4000, turn: -90, doors: [] }],
      },
    ]);
    const encoded = encodeState(result.state);
    expect(encoded).not.toMatch(/count|polygon|stocks|pieces|JSON|plan=/);
    expect(new URLSearchParams(encoded).has('room.1.wall.2.length')).toBe(false);
  });

  it('rejects duplicate fields and the retired stock-list field', () => {
    expectInvalid('?flooring.length=1200&flooring.length=1400', /only once/);
    expectInvalid('?selectedRoom=one&selectedRoom=two', /only once/);
    expectInvalid('?room.1.name=Office&room.1.name=Kitchen', /only once/);
    expectInvalid('?skirting.length=2400&skirting.length=3600', /only once/);
    expectInvalid('?skirting.stock=2400', /retired skirting stock-list/);
  });

  it('rejects sparse, zero, malformed and excessive indices', () => {
    expectInvalid('?room.2.id=second', /consecutive/);
    expectInvalid('?room.0.id=zero', /positive whole numbers/);
    expectInvalid('?room.one.id=one', /positive whole numbers/);
    expectInvalid(`?room.${PROJECT_LIMITS.rooms + 1}.id=excess`, /at most 20/);
    expectInvalid(`?room.1.wall.${PROJECT_LIMITS.wallsPerRoom + 1}.length=4000`, /at most 100/);
    expectInvalid(
      `?room.1.wall.1.length=4000&room.1.wall.1.door.${PROJECT_LIMITS.doorsPerWall + 1}.width=500`,
      /at most 30/,
    );
  });

  it('rejects impossible collections and oversized strings before encoding', () => {
    const empty = defaultState();
    empty.project.rooms = [];
    expect(() => encodeState(empty)).toThrow(/at least one room/);

    const duplicate = defaultState();
    duplicate.project.rooms.push(rectangle());
    expect(() => encodeState(duplicate)).toThrow(/duplicate identifiers/);

    const rooms = defaultState();
    rooms.project.rooms = Array.from({ length: PROJECT_LIMITS.rooms + 1 }, (_, index) =>
      rectangle(`room-${index}`),
    );
    expect(() => encodeState(rooms)).toThrow(/at most 20/);

    const walls = defaultState();
    walls.project.rooms[0].walls = Array.from(
      { length: PROJECT_LIMITS.wallsPerRoom + 1 },
      (_, index) => ({ id: `wall-${index}`, length: 1, turn: 90, doors: [] }),
    );
    expect(() => encodeState(walls)).toThrow(/at most 100/);

    const doors = defaultState();
    doors.project.rooms[0].walls[0].doors = Array.from(
      { length: PROJECT_LIMITS.doorsPerWall + 1 },
      (_, index) => ({ id: `door-${index}`, offset: index * 10, width: 5 }),
    );
    expect(() => encodeState(doors)).toThrow(/at most 30/);

    const name = defaultState();
    name.project.name = 'a'.repeat(PROJECT_LIMITS.nameLength + 1);
    expect(() => encodeState(name)).toThrow(/at most 200 characters/);
  });

  it('bounds progress, search and total query length', () => {
    const state = defaultState();
    state.project.completedBoards = Array.from(
      { length: PERSISTENCE_LIMITS.completedBoards + 1 },
      (_, index) => `floor:B${index + 1}`,
    );
    expect(() => encodeState(state)).toThrow(/at most 12000/);
    expectInvalid(
      `?search=${'a'.repeat(PERSISTENCE_LIMITS.searchLength + 1)}`,
      /at most 200 characters/,
    );
    expectInvalid(`?name=${'x'.repeat(PERSISTENCE_LIMITS.queryLength)}`, /link is too large/);
  });

  it('rejects damaged percent encoding', () => {
    expectInvalid('?name=%', /invalid URL encoding/);
    expectInvalid('?name=%C0%AF', /invalid URL encoding/);
  });
});