Purpose

Document the shipped Hitori built-in game behavior.

Requirements

Requirement: Registry Metadata

Hitori SHALL be registered as a built-in game with canonical description "Shade the cells to eliminate duplicates.", aliases none, variants Hitori (default 1800 Elo), and daily legacy modes easy, medium.

Scenario: Resolve Hitori

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

Requirement: Variant Elo Creation

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

Scenario: Spawn Hitori by Elo

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

Requirement: Legacy Mode Compatibility

Hitori SHALL preserve legacy named modes as compatibility presets that map to the Hitori variant and preset Elo values: Mini (300 Elo), Easy (700 Elo), Medium (1300 Elo), Tricky (1800 Elo), Hard (2300 Elo), Expert (2800 Elo).

Scenario: Use legacy mode title

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

Requirement: Puzzle Rules

The Hitori runtime MUST let players shade cells so each row and column has no duplicate unshaded numbers, shaded cells are never orthogonally adjacent, and all unshaded cells remain connected.

Scenario: Check solved state

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

Requirement: Save Load And Interaction

Hitori 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 shading controls are required, and mouse click-to-focus support MUST be available.

Scenario: Resume saved Hitori

• WHEN a saved Hitori 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 Hitori print adapter SHALL render puzzle and solution data for JSONL-to-PDF workflows.

Scenario: Export Hitori

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