# Bun Reader

Reads Go source files containing Bun model definitions and extracts database schema information.

## Overview

The Bun Reader parses Go source code files that define Bun models (structs with `bun` struct tags) and converts them into RelSpec's internal database model representation.

## Features

- Parses Bun struct tags to extract column definitions
- Extracts table names from `bun:"table:tablename"` tags
- Identifies primary keys, foreign keys, and indexes
- Supports relationship detection
- Handles both single files and directories

## Usage

### Basic Example

```go
package main

import (
    "fmt"
    "git.warky.dev/wdevs/relspecgo/pkg/readers"
    "git.warky.dev/wdevs/relspecgo/pkg/readers/bun"
)

func main() {
    options := &readers.ReaderOptions{
        FilePath: "/path/to/models.go",
    }

    reader := bun.NewReader(options)
    db, err := reader.ReadDatabase()
    if err != nil {
        panic(err)
    }

    fmt.Printf("Found %d schemas\n", len(db.Schemas))
}
```

### CLI Example

```bash
# Read Bun models and convert to JSON
relspec --input bun --in-file models/ --output json --out-file schema.json

# Convert Bun models to GORM
relspec --input bun --in-file models.go --output gorm --out-file gorm_models.go
```

## Supported Bun Tags

The reader recognizes the following Bun struct tags:

- `table` - Table name
- `column` - Column name
- `type` - SQL data type
- `pk` - Primary key
- `notnull` - NOT NULL constraint
- `autoincrement` - Auto-increment column
- `default` - Default value
- `unique` - Unique constraint
- `rel` - Relationship definition

## Example Bun Model

```go
package models

import (
    "time"
    "github.com/uptrace/bun"
)

type User struct {
    bun.BaseModel `bun:"table:users,alias:u"`

    ID        int64     `bun:"id,pk,autoincrement"`
    Username  string    `bun:"username,notnull,unique"`
    Email     string    `bun:"email,notnull"`
    CreatedAt time.Time `bun:"created_at,notnull,default:now()"`

    Posts []*Post `bun:"rel:has-many,join:id=user_id"`
}

type Post struct {
    bun.BaseModel `bun:"table:posts,alias:p"`

    ID      int64  `bun:"id,pk"`
    UserID  int64  `bun:"user_id,notnull"`
    Title   string `bun:"title,notnull"`
    Content string `bun:"content"`

    User *User `bun:"rel:belongs-to,join:user_id=id"`
}
```

## Notes

- Test files (ending in `_test.go`) are automatically excluded
- The `bun.BaseModel` embedded struct is automatically recognized
- Schema defaults to `public` if not specified