# EVOLV - Claude Code Project Guide

> **READ FIRST, BEFORE ANY OTHER WORK:**
> 1. [`CONTRACTS.md`](./CONTRACTS.md) — front-door map: where every contract, rule, and standard lives, and how to find them.
> 2. [`.claude/rules/repo-mem.md`](./.claude/rules/repo-mem.md) — this repo has an MCP server (`repo-mem`) exposing a substrate-trained `repo_search` and a persistent fix-trace store. Use those instead of `grep` for concept queries, and record completed fixes via `repo_record_fix`.

## What This Is
Node-RED custom nodes package for wastewater treatment plant automation. Developed by Waterschap Brabantse Delta R&D team. Follows ISA-88 (S88) batch control standard.

## Architecture
Each node follows a three-layer pattern:
1. **Node-RED wrapper** (`<name>.js`) - registers the node type, sets up HTTP endpoints
2. **Node adapter** (`src/nodeClass.js`) - bridges Node-RED API with domain logic, handles config loading, tick loops, events
3. **Domain logic** (`src/specificClass.js`) - pure business logic, no Node-RED dependencies

## Key Shared Library: `nodes/generalFunctions/`
- `logger` - structured logging (use this, NOT console.log)
- `MeasurementContainer` - chainable measurement storage (type/variant/position)
- `configManager` - loads JSON configs from `src/configs/`
- `MenuManager` - dynamic UI dropdowns
- `outputUtils` - formats messages for InfluxDB and process outputs
- `childRegistrationUtils` - parent-child node relationships
- `coolprop` - thermodynamic property calculations

## Conventions
- Nodes register under category `'EVOLV'` in Node-RED
- S88 color scheme: Area=#0f52a5, ProcessCell=#0c99d9, Unit=#50a8d9, Equipment=#86bbdd, ControlModule=#a9daee
- Config JSON files in `generalFunctions/src/configs/` define defaults, types, enums per node
- Tick loop runs at 1000ms intervals for time-based updates
- Output ports + 3-tier architecture: see `.claude/rules/node-architecture.md`
- **Multi-tab demo flows**: see `.claude/rules/node-red-flow-layout.md` for the tab/link-channel/spacing rule set used by `examples/`
- **Output coverage** (every output, every state, every layer): see `.claude/rules/output-coverage.md` — manifest + populated/degraded tests are mandatory for any change that touches Port 0/1/2 keys, function-node fan-outs, telemetry fields, or dashboard widget sources

## Sources of truth (the canonical files)
- **Front-door map**: [`CONTRACTS.md`](./CONTRACTS.md) — read first; lists every standard and where it lives
- **Platform API shapes** (BaseDomain, BaseNodeAdapter, commands registry, UnitPolicy, …): `.claude/refactor/CONTRACTS.md`
- **Code conventions** (file/function size, comments, naming): `.claude/refactor/CONVENTIONS.md`
- **Per-node module layout**: `.claude/refactor/MODULE_SPLIT.md`
- **Per-node API contract**: `nodes/<n>/CONTRACT.md` + `nodes/<n>/src/commands/index.js` (source of truth for accepted `msg.topic` values)
- **Shared library API**: `nodes/generalFunctions/CONTRACT.md` (exported classes + utilities)
- **Live decisions log**: `.claude/refactor/OPEN_QUESTIONS.md` — append, don't invent

## Development Notes
- No build step required - pure Node.js
- Install: `npm install` in root
- Submodule URLs were rewritten from `gitea.centraal.wbd-rd.nl` to `gitea.wbd-rd.nl` for external access
- Dependencies: mathjs, generalFunctions (git submodule)