# Phase 3: Project Context Awareness - Quick Reference

**Status**: PLANNING → READY TO START
**Estimated Duration**: 3-4 sessions (12-16 hours)

---

## 🎯 Goal

Transform Tractatus from **single-project** to **multi-project** governance system with context-aware variable substitution.

---

## 📊 Architecture at a Glance

```
USER ACTION:                  SYSTEM RESPONSE:
┌─────────────────┐          ┌────────────────────────────────┐
│ Select Project  │          │ 1. Load applicable rules       │
│ "tractatus"     │──────────>│ 2. Fetch variable values       │
└─────────────────┘          │ 3. Substitute ${VAR} → value   │
                             │ 4. Display rendered text       │
                             └────────────────────────────────┘

BEFORE (Template):
"MongoDB database MUST be named ${DB_NAME} in ${ENVIRONMENT}"

AFTER (Rendered for "tractatus"):
"MongoDB database MUST be named tractatus_dev in development"

AFTER (Rendered for "family-history"):
"MongoDB database MUST be named family_history in production"
```

---

## 🏗️ What We're Building

### Backend (Session 1-2)

#### Models
- ✅ **Project** - Store project metadata (id, name, tech stack)
- ✅ **VariableValue** - Store variable values per project

#### Services
- ✅ **VariableSubstitution** - Replace `${VAR}` with actual values

#### APIs
- ✅ **Projects API** - CRUD for projects
- ✅ **Variables API** - CRUD for variable values
- ✅ **Enhanced Rules API** - Return rules with substituted values

### Frontend (Session 3)

#### Components
- ✅ **Project Selector** - Dropdown in navbar
- ✅ **Project Manager** - Table view of all projects
- ✅ **Project Editor** - Form for project details + variable values
- ✅ **Variable Editor** - Modal for editing individual variables

#### Enhancements
- ✅ **Rule Manager** - Show rendered text for selected project

---

## 📋 Task Breakdown (4 Sessions)

### Session 1: Backend Foundation (3-4 hours)
```
1. Create Project.model.js
2. Create VariableValue.model.js
3. Create VariableSubstitution.service.js
4. Write unit tests for substitution logic
```

### Session 2: Backend APIs (3-4 hours)
```
5. Create projects.controller.js + routes
6. Create variables.controller.js + routes
7. Enhance rules.controller.js (add project context)
8. Write API integration tests
```

### Session 3: Frontend UI (4-5 hours)
```
9. Create project-manager.html
10. Create project-editor.js
11. Create project-selector.js component
12. Enhance rule-manager.js (show rendered text)
13. Create variable-editor.js modal
```

### Session 4: Testing & Docs (2-3 hours)
```
14. Create seed-projects.js (sample data)
15. Frontend integration testing
16. Write docs/api/PROJECTS_API.md
17. Write docs/USER_GUIDE_PROJECTS.md
```

---

## 🔑 Key Features

### 1. Variable Substitution
```javascript
// Template Rule
text: "Use port ${APP_PORT} for ${APP_NAME}"
variables: ["APP_PORT", "APP_NAME"]

// Project: tractatus
variables: {
  APP_PORT: "9000",
  APP_NAME: "Tractatus"
}

// Rendered
"Use port 9000 for Tractatus"
```

### 2. Project Filtering
```javascript
// Rule with scope
{
  scope: "PROJECT_SPECIFIC",
  applicableProjects: ["tractatus", "family-history"]
}

// When project="tractatus" selected
// Show: UNIVERSAL rules + rules with "tractatus" in applicableProjects
```

### 3. Context-Aware Display
```
┌─────────────────────────────────────────────────┐
│ Rule Manager          [Project: Tractatus ▼]   │
├─────────────────────────────────────────────────┤
│ inst_019 | SYSTEM | HIGH                        │
│                                                  │
│ Rendered (for Tractatus):                       │
│ MongoDB database MUST be named tractatus_dev    │
│                                                  │
│ Template: ...${DB_NAME}...                      │
│ Variables: DB_NAME=tractatus_dev                │
└─────────────────────────────────────────────────┘
```

---

## 💾 Database Schema

### Project
```javascript
{
  id: 'tractatus',                    // PK, unique
  name: 'Tractatus Framework',
  description: 'Agentic governance framework',
  techStack: {
    language: 'JavaScript',
    framework: 'Node.js/Express',
    database: 'MongoDB',
    frontend: 'Vanilla JS'
  },
  active: true
}
```

### VariableValue
```javascript
{
  projectId: 'tractatus',             // FK to Project.id
  variableName: 'DB_NAME',            // Variable name
  value: 'tractatus_dev',             // Actual value
  description: 'Development database name',
  category: 'database'                // database/config/path/url
}
```

**Compound Unique Index**: `(projectId, variableName)`

---

## 🔄 Data Flow Example

### Creating a Project with Variables

```bash
# 1. Create project
POST /api/admin/projects
{
  "id": "tractatus",
  "name": "Tractatus Framework",
  "techStack": { "database": "MongoDB" }
}

# 2. Add variable values
POST /api/admin/projects/tractatus/variables
{
  "variableName": "DB_NAME",
  "value": "tractatus_dev",
  "category": "database"
}

# 3. Get rules with substitution
GET /api/admin/rules?project=tractatus

# Response includes rendered text
{
  "rules": [{
    "id": "inst_019",
    "text": "...${DB_NAME}...",
    "renderedText": "...tractatus_dev...",
    "variables": [{"name": "DB_NAME", "value": "tractatus_dev"}]
  }]
}
```

---

## ✅ Success Criteria

### Functional
- ✅ Create/edit/delete projects
- ✅ Set variable values per project
- ✅ View rules with substituted values
- ✅ Switch between projects
- ✅ Detect missing variables

### Technical
- ✅ Substitution performance < 50ms
- ✅ All APIs tested (integration)
- ✅ Frontend components functional
- ✅ Database indexes optimized

### UX
- ✅ Intuitive project switching
- ✅ Clear template vs rendered distinction
- ✅ Easy variable editing
- ✅ Helpful error messages

---

## 🚀 Getting Started

### Session 1 Tasks
1. Create `src/models/Project.model.js`
2. Create `src/models/VariableValue.model.js`
3. Create `src/services/VariableSubstitution.service.js`
4. Write tests: `tests/unit/VariableSubstitution.test.js`

**Start Command**:
```bash
# Create model files
touch src/models/Project.model.js
touch src/models/VariableValue.model.js
touch src/services/VariableSubstitution.service.js
touch tests/unit/VariableSubstitution.test.js
```

---

## 📚 Reference Documents

- **Full Plan**: `docs/planning/PHASE_3_PROJECT_CONTEXT_PLAN.md`
- **Phase 1 Complete**: `docs/USER_GUIDE_RULE_MANAGER.md`
- **Phase 2 Complete**: `docs/testing/PHASE_2_TEST_RESULTS.md`
- **Coding Best Practices**: `docs/governance/CODING_BEST_PRACTICES_SUMMARY.md`

---

## 🎯 Next Actions

**Ready to start?** Say:
- "Start Phase 3 Session 1" - Begin backend foundation
- "Show me the full plan" - Review detailed plan
- "Modify the plan" - Adjust scope or approach

---

**Plan Status**: ✅ APPROVED - READY TO BUILD
**Est. Completion**: 3-4 sessions from now
**Dependencies**: None (Phase 1 & 2 complete)