---
phase: 03-visual-flattening
plan: 02
type: execute
wave: 2
depends_on: ["03-01"]
files_modified:
  - SportsTimeTests/ItineraryFlattenerTests.swift
autonomous: true

must_haves:
  truths:
    - "Same semantic state produces identical row order on repeated flattening"
    - "Item with sortOrder -1.0 appears before all games in that day"
    - "Reordering an item and re-flattening preserves the new order"
  artifacts:
    - path: "SportsTimeTests/ItineraryFlattenerTests.swift"
      provides: "Determinism and ordering tests"
      min_lines: 80
  key_links:
    - from: "ItineraryFlattenerTests"
      to: "ItineraryFlattener.flatten()"
      via: "test assertions"
      pattern: "ItineraryFlattener\\.flatten"
---

<objective>
Add tests verifying ItineraryFlattener produces deterministic, sortOrder-based output.

Purpose: Ensure the three success criteria from ROADMAP.md are verifiable through automated tests.

Output: New test file `ItineraryFlattenerTests.swift` with tests covering all success criteria.
</objective>

<execution_context>
@~/.claude/get-shit-done/workflows/execute-plan.md
@~/.claude/get-shit-done/templates/summary.md
</execution_context>

<context>
@.planning/PROJECT.md
@.planning/ROADMAP.md
@.planning/STATE.md
@.planning/phases/03-visual-flattening/03-RESEARCH.md
@.planning/phases/03-visual-flattening/03-01-SUMMARY.md
@SportsTime/Core/Models/Domain/ItineraryFlattener.swift
@SportsTime/Core/Models/Domain/SortOrderProvider.swift
@SportsTimeTests/ItineraryConstraintsTests.swift
</context>

<tasks>

<task type="auto">
  <name>Task 1: Create ItineraryFlattenerTests with determinism tests</name>
  <files>SportsTimeTests/ItineraryFlattenerTests.swift</files>
  <action>
Create a new test file `ItineraryFlattenerTests.swift` using Swift Testing (`@Suite`, `@Test`).

Test suite structure:
```swift
import Testing
@testable import SportsTime

@Suite("ItineraryFlattener")
struct ItineraryFlattenerTests {
    // Test helper to create mock ItineraryDayData
    // Test helper to create mock RichGame
    // Test helper to create mock ItineraryItem
}
```

Required tests (map directly to ROADMAP success criteria):

1. **success_negativeSortOrderAppearsBeforeGames** (Success Criterion 1)
   - Create item with sortOrder = -1.0
   - Create games with sortOrder ~820 (noon game)
   - Flatten and verify custom item index < games index
   - Assert: "Item with sortOrder -1.0 appears before all games in that day's section"

2. **success_sameStateProducesIdenticalOrder** (Success Criterion 2)
   - Create fixed test data (2 days, games, travel, custom items)
   - Flatten twice
   - Compare resulting row IDs
   - Assert: arrays are identical (not just equal length)

3. **success_reorderPreservesNewOrder** (Success Criterion 3)
   - Create items with sortOrder 1.0, 2.0, 3.0
   - Simulate reorder: change item from 1.0 to 2.5
   - Flatten
   - Verify new order is [2.0, 2.5, 3.0] not [1.0, 2.0, 3.0]

Additional tests for comprehensive coverage:

4. **flatten_dayHeaderAlwaysFirst**
   - Verify first item for each day is `.dayHeader`

5. **flatten_sortsByDayThenSortOrder**
   - Items on day 1 appear before items on day 2
   - Within each day, items sorted by sortOrder

6. **flatten_gamesGetSortOrderFromTime**
   - Game at 8:00 PM (sortOrder ~1180) appears after item with sortOrder 500
   - Game at 1:00 PM (sortOrder ~880) appears before item with sortOrder 1000

7. **flatten_emptyDayHasOnlyHeader**
   - Day with no games, no items produces only `.dayHeader` row

8. **flatten_multipleGamesOnSameDay**
   - Day with 2 games: both included in single `.games` row
   - Custom items around games sort correctly

Test helpers needed:
- `makeGame(id:, stadium:, dateTime:)` -> RichGame
- `makeItem(day:, sortOrder:, kind:)` -> ItineraryItem
- `makeDayData(dayNumber:, date:, games:, items:)` -> ItineraryDayData
  </action>
  <verify>
Run tests: `xcodebuild -project SportsTime.xcodeproj -scheme SportsTime -destination 'platform=iOS Simulator,name=iPhone 17,OS=26.2' -only-testing:SportsTimeTests/ItineraryFlattenerTests test 2>&1 | grep -E "(Test Suite|passed|failed|error:)"`
  </verify>
  <done>
`ItineraryFlattenerTests.swift` exists with:
- 3 success_* tests mapping to ROADMAP success criteria
- 5+ additional tests for comprehensive coverage
- All tests passing
  </done>
</task>

<task type="auto">
  <name>Task 2: Verify existing behavior unchanged</name>
  <files>SportsTimeTests/ItineraryFlattenerTests.swift</files>
  <action>
Add integration-style tests that verify the refactored flattening produces expected behavior for realistic trip data.

Additional tests:

1. **flatten_travelWithNegativeSortOrderAppearsBeforeGames**
   - Travel item with sortOrder = -5.0
   - Should appear before games in same day

2. **flatten_travelWithPositiveSortOrderAppearsAfterGames**
   - Travel item with sortOrder = 1500.0 (after noon game)
   - Should appear after games in same day

3. **flatten_mixedItemTypes**
   - Day with: travel (-5), custom (-1), games (820), custom (900), travel (1500)
   - Verify exact order: header, travel, custom, games, custom, travel

4. **flatten_multiDayTrip**
   - 3-day trip with different item configurations per day
   - Verify each day's items are independent and sorted correctly

Run full test suite to ensure no regressions:
`xcodebuild -project SportsTime.xcodeproj -scheme SportsTime -destination 'platform=iOS Simulator,name=iPhone 17,OS=26.2' test`
  </action>
  <verify>
Full test suite passes: `xcodebuild -project SportsTime.xcodeproj -scheme SportsTime -destination 'platform=iOS Simulator,name=iPhone 17,OS=26.2' test 2>&1 | grep -E "(Test Suite|passed|failed)" | tail -10`
  </verify>
  <done>
- All ItineraryFlattenerTests passing (12+ tests)
- Full test suite passes (no regressions)
- Tests cover all three ROADMAP success criteria
  </done>
</task>

</tasks>

<verification>
1. All tests in `ItineraryFlattenerTests.swift` pass
2. Tests explicitly named `success_*` map to ROADMAP success criteria:
   - success_negativeSortOrderAppearsBeforeGames -> Criterion 1
   - success_sameStateProducesIdenticalOrder -> Criterion 2
   - success_reorderPreservesNewOrder -> Criterion 3
3. Full test suite passes (no regressions from refactoring)
</verification>

<success_criteria>
- FLAT-02: Flattening is deterministic and stateless (verified by success_sameStateProducesIdenticalOrder test)
- All three ROADMAP success criteria have corresponding tests
</success_criteria>

<output>
After completion, create `.planning/phases/03-visual-flattening/03-02-SUMMARY.md`
</output>