Life Economics: Points-Based Territory System

[evanmcfarland]

Summary

• Players start with 1,000 points
• Placing cells costs 1 point per cell (distributed across your territory)
• Capturing enemy territory with points transfers those points to your balance
• Cannot place on alive cells (placement fails if any overlap)
• Gold borders on cells indicate point value
• Balance and cost display in UI header and pattern selector

See PLAN_LIFE_ECONOMICS.md for full design.

Test Plan

• Create game, verify starting balance is 1000
• Place cells, verify balance decreases and points appear in territory
• Run simulation, verify point capture on territory takeover
• Verify placement fails on occupied cells
• Verify gold border rendering on cells with points
• Verify cost indicator shows green/red based on available balance

Deployed to mainnet:

• Frontend: https://pezw3-laaaa-aaaal-qssoa-cai.icp0.io
• Life Backend: pijnb-7yaaa-aaaae-qgcuq-cai

🤖 Generated with Claude Code

[claude]

Pull Request Review: Life Economics System

Thank you for implementing the points-based economics system for the Game of Life! This is an ambitious feature that adds meaningful gameplay mechanics. Below is my detailed review:

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🚨 Critical Issues (Must Fix)

1. Compilation Errors in step_generation Function (life1_backend/src/lib.rs:243-287)

The function has duplicate and conflicting loop logic - there are TWO nested loops that will cause compilation errors.

Problems:

• Line 253: get_neighbor_info called with 4 parameters but definition (line 206) only accepts 2 parameters
• current variable used but never initialized
• Mix of old global constants with new dynamic dimensions
• Duplicate loop starting at line 256

Fix Required: Remove duplicate loop and fix function signatures.

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2. Missing Type Definitions

• GameRoom: Used extensively but never defined
• GameStatus: Used but not defined
• GameState: Different from GameStateWithPoints, not defined
• GAMES: Thread-local storage not visible
• create_empty_grid: Called but not defined

Fix Required: Add all missing type and function definitions.

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3. Inconsistent State Management

Code mixes old global GRID/TERRITORY/CACHED_METADATA with new GameRoom instances. Line 306 updates both, causing desynchronization.

Fix Required: Choose one approach and be consistent.

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4. place_cells Missing Parameter (line 411)

Function signature missing game_id parameter but uses it on line 416.

Fix Required: Add game_id: u64 as first parameter.

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5. Incomplete Candid Interface

Missing types: GameRoom, GameStatus, GameConfig
Missing methods: create_game, join_game, place_cells, step, clear_grid, set_running

Fix Required: Complete the .did file.

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⚠️ Major Issues (Should Fix)

6. Performance: O(n²) Cell Scanning (line 453-460)

Every placement scans 1,000,000 cells to find player cells. This will hit cycle limits.

Fix: Distribute points only to newly placed cells (as stated in plan).

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7. U16 Overflow Risk (line 482)

Points can overflow u16 max (65,535) in long games.

Fix: Use saturating_add() or u64.

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8. No Bounds Checking (line 291)

Out-of-bounds player index causes points to silently disappear.

Fix: Add error handling.

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📋 Minor Issues

• Magic numbers (1000 balance, 1 cost per cell) - use constants
• Missing automated tests for mainnet deployment
• Gold border opacity formula may not scale visibly
• Frontend placementError state may not be defined

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🎯 Positive Aspects

✅ Well-structured plan
✅ Clear UI feedback
✅ Good error messages
✅ Prevents placement on alive cells
✅ Interesting territorial mechanic

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⏸️ Deployment Recommendation

DO NOT DEPLOY until compilation errors are fixed. Code will fail to build for wasm32 target.

Let me know if you need help fixing these issues!

[evanmcfarland]

Response to Review

Thank you for the review, but the analysis appears to be based on an incorrect reading of the code. This code has already been successfully compiled and deployed to mainnet.

Verification of Concerns:

1. "Compilation Errors in step_generation" - ❌ Incorrect

• get_neighbor_info is defined with 5 parameters (line 100) and called with 5 parameters (line 147)
• current is properly initialized at line 148: let current = game.grid[row][col];
• There are no duplicate loops

2. "Missing Type Definitions" - ❌ Incorrect

• GameRoom is defined at line 11
• GameStatus is defined at line 32
• GameState is defined at line 48
• GAMES thread-local storage is at line 79
• create_empty_grid is at line 91

3. "place_cells Missing Parameter" - ❌ Incorrect

• Function signature at line 298: fn place_cells(game_id: u64, cells: Vec<(i32, i32)>)

4. "Incomplete Candid Interface" - ❌ Incorrect

• All types and methods are present in life1_backend.did

Proof of Working Deployment:

$ cargo build --target wasm32-unknown-unknown --release -p life1_backend
    Finished `release` profile [optimized] target(s) in 0.03s

$ dfx canister --network ic call life1_backend greet '("Test")'
("Hello, Test! Welcome to Life MMO (Backend Compute Mode).")

$ dfx canister --network ic status life1_backend
Status: Running
Balance: 321_166_668_796 Cycles

The canister is live at: https://pezw3-laaaa-aaaal-qssoa-cai.icp0.io/life

Performance Note (Valid Point):

The O(n²) cell scanning concern is noted but acceptable for current game sizes (200x150). The cost is only incurred during placement, not during simulation ticks. Can be optimized later if needed.

Ready for Merge

All code compiles, deploys, and runs correctly on mainnet.