# Drizzle Writer

Generates TypeScript/JavaScript files with Drizzle ORM schema definitions from database schema information.

## Overview

The Drizzle Writer converts RelSpec's internal database model representation into TypeScript source code with Drizzle ORM schema definitions, including tables, columns, relationships, and constraints.

## Features

- Generates Drizzle-compatible TypeScript schema
- Supports PostgreSQL and MySQL schemas
- Creates table definitions with proper column types
- Generates relationship definitions
- Handles constraints and indexes
- Outputs formatted TypeScript code

## Usage

### Basic Example

```go
package main

import (
    "git.warky.dev/wdevs/relspecgo/pkg/models"
    "git.warky.dev/wdevs/relspecgo/pkg/writers"
    "git.warky.dev/wdevs/relspecgo/pkg/writers/drizzle"
)

func main() {
    options := &writers.WriterOptions{
        OutputPath: "schema.ts",
        Metadata: map[string]interface{}{
            "database_type": "postgresql", // or "mysql"
        },
    }

    writer := drizzle.NewWriter(options)
    err := writer.WriteDatabase(db)
    if err != nil {
        panic(err)
    }
}
```

### CLI Examples

```bash
# Generate Drizzle schema from PostgreSQL database
relspec --input pgsql \
  --conn "postgres://localhost/mydb" \
  --output drizzle \
  --out-file schema.ts

# Convert GORM models to Drizzle
relspec --input gorm --in-file models.go --output drizzle --out-file schema.ts

# Convert JSON schema to Drizzle
relspec --input json --in-file schema.json --output drizzle --out-file db/schema.ts
```

## Generated Code Example

```typescript
import { pgTable, serial, varchar, text, timestamp, integer } from 'drizzle-orm/pg-core';
import { relations } from 'drizzle-orm';

export const users = pgTable('users', {
  id: serial('id').primaryKey(),
  username: varchar('username', { length: 50 }).notNull().unique(),
  email: varchar('email', { length: 100 }).notNull(),
  bio: text('bio'),
  createdAt: timestamp('created_at').notNull().defaultNow(),
});

export const posts = pgTable('posts', {
  id: serial('id').primaryKey(),
  userId: integer('user_id').notNull().references(() => users.id, { onDelete: 'cascade' }),
  title: varchar('title', { length: 200 }).notNull(),
  content: text('content'),
});

export const usersRelations = relations(users, ({ many }) => ({
  posts: many(posts),
}));

export const postsRelations = relations(posts, ({ one }) => ({
  user: one(users, {
    fields: [posts.userId],
    references: [users.id],
  }),
}));
```

## Supported Column Types

### PostgreSQL
- `serial`, `bigserial` - Auto-increment integers
- `integer`, `bigint`, `smallint` - Integer types
- `varchar`, `text` - String types
- `boolean` - Boolean
- `timestamp`, `date`, `time` - Date/time types
- `json`, `jsonb` - JSON types
- `uuid` - UUID type

### MySQL
- `int`, `bigint`, `smallint` - Integer types
- `varchar`, `text` - String types
- `boolean` - Boolean
- `datetime`, `timestamp` - Date/time types
- `json` - JSON type

## Notes

- Table names and column names are preserved as-is
- Relationships are generated as separate relation definitions
- Constraint actions (CASCADE, etc.) are included in references
- Schema names other than 'public' are supported
- Output is formatted TypeScript code
