Purpose

Document the shipped Sudoku built-in game behavior.

Requirements

Requirement: Registry Metadata

Sudoku SHALL be registered as a built-in game with canonical description "Fill the 9x9 grid following sudoku rules.", aliases none, variants Sudoku (default 1800 Elo), and daily legacy modes easy, medium.

Scenario: Resolve Sudoku

• WHEN the registry resolves the canonical name or any alias
• THEN it returns the Sudoku entry with help text, import behavior, variant metadata, and legacy mode compatibility

Requirement: Variant Elo Creation

Sudoku MUST support the current variant plus target Elo creation path, using the variant default Elo when no explicit target is supplied.

Scenario: Spawn Sudoku by Elo

• WHEN the user selects the Sudoku variant and a target Elo from 0 through 3000
• THEN PuzzleTea spawns a deterministic Sudoku puzzle and records target, actual, and confidence metadata when generation reports it

Requirement: Legacy Mode Compatibility

Sudoku SHALL preserve legacy named modes as compatibility presets that map to the Sudoku variant and preset Elo values: Beginner (0 Elo), Easy (600 Elo), Medium (1200 Elo), Hard (1800 Elo), Expert (2400 Elo), Diabolical (3000 Elo).

Scenario: Use legacy mode title

• WHEN the user supplies a legacy Sudoku mode title through CLI or deterministic daily metadata
• THEN PuzzleTea resolves it to the Sudoku variant and the registered preset Elo

Requirement: Puzzle Rules

The Sudoku runtime MUST let players fill a 9x9 grid so every row, column, and 3x3 box contains digits 1 through 9 exactly once while preserving givens.

Scenario: Check solved state

• WHEN the player fills the board or word state
• THEN Sudoku reports solved only when all rule constraints are satisfied

Requirement: Save Load And Interaction

Sudoku SHALL serialize enough state for resume/import, reset to its initial puzzle, expose debug and full-help data, and support its shipped interaction model. Keyboard digit entry is required, and mouse click-to-focus support MUST be available.

Scenario: Resume saved Sudoku

• WHEN a saved Sudoku payload is imported
• THEN the restored game preserves givens, player entries, cursor/selection state where applicable, and solved-state behavior

Requirement: Print Export Support

The Sudoku print adapter SHALL render puzzle and solution data for JSONL-to-PDF workflows.

Scenario: Export Sudoku

• WHEN Sudoku is included in a JSONL or PDF export flow
• THEN PuzzleTea follows the registered print support behavior for that game