Backend Services

worker/src/
├── services/
│   ├── r2.ts              # R2 storage service
│   └── summarization.ts   # AI summarization service
├── handlers/
│   ├── signup.ts          # Signup handler
│   └── upload.ts          # Upload handler
└── utils/
    ├── r2-keys.ts         # R2 key generation
    ├── uuid.ts            # UUID generation
    └── password.ts        # Password hashing

async function uploadToR2(
  bucket: R2Bucket,
  key: string,
  content: string,
  metadata: Record<string, string>
): Promise<void>

await uploadToR2(
  env.metacogna_vault,
  'users/user-123/documents/doc.pdf',
  pdfContent,
  { userId: 'user-123', docId: 'doc-456', title: 'Document Title' }
);

function generateR2DocumentKey(
  userId: string,
  docId: string,
  filename: string
): string {
  return `users/${userId}/documents/${docId}-${filename}`;
}

async function summarizeGoals(
  ai: any,
  rawGoals: string
): Promise<string>

async function handleSignup(
  request: Request,
  env: Env
): Promise<Response>

async function handleMultiFileUpload(
  request: Request,
  env: Env
): Promise<UploadResponse>

function generateUUID(): string

function generateR2DocumentKey(
  userId: string,
  docId: string,
  filename: string
): string

async function hashPassword(
  username: string,
  password: string
): Promise<string>

CREATE TABLE users (
    id TEXT PRIMARY KEY,
    username TEXT UNIQUE NOT NULL,
    email TEXT UNIQUE,
    name TEXT,
    passwordHash TEXT NOT NULL,
    goals TEXT,
    isAdmin BOOLEAN DEFAULT 0,
    createdAt INTEGER NOT NULL,
    lastLogin INTEGER
);

CREATE TABLE documents (
    id TEXT PRIMARY KEY,
    userId TEXT REFERENCES users(id),
    title TEXT NOT NULL,
    content TEXT,              -- Preview (first 500 chars)
    r2Key TEXT,                -- R2 object key
    metadata TEXT,             -- JSON string
    status TEXT DEFAULT 'completed',
    createdAt INTEGER NOT NULL,
    uploadedAt INTEGER
);

CREATE TABLE graph_nodes (
    id TEXT PRIMARY KEY,
    label TEXT NOT NULL,
    type TEXT NOT NULL,        -- Entity type (Concept, Person, etc.)
    summary TEXT,
    documentId TEXT
);

CREATE TABLE graph_edges (
    id TEXT PRIMARY KEY,
    source TEXT NOT NULL,
    target TEXT NOT NULL,
    relation TEXT NOT NULL,
    documentId TEXT,
    FOREIGN KEY (source) REFERENCES graph_nodes(id),
    FOREIGN KEY (target) REFERENCES graph_nodes(id)
);

const cacheKey = 'graph:latest';
await env.KV.put(cacheKey, JSON.stringify(graphData), {
  expirationTtl: 300  // 5 minutes
});

try {
  // Service operation
} catch (error) {
  console.error('Service error:', error);
  return errorResponse('Service operation failed', 500);
}