# Guide: Creating New OSIRIS Objects

This guide explains how to properly create new object types in OSIRIS that integrate with the Rhai scripting engine and context storage.

## Step-by-Step Process

### 1. Create the Object Module

Create a new file in the appropriate directory under `src/objects/`:
- `src/objects/legal/` for legal objects
- `src/objects/money/` for financial objects
- `src/objects/heroledger/` for HeroLedger objects
- etc.

### 2. Define the Object Struct

**CRITICAL**: The struct MUST derive `crate::DeriveObject` to automatically implement the `Object` trait.

```rust
use crate::store::BaseData;
use serde::{Deserialize, Serialize};

/// Your object description
#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, crate::DeriveObject)]
pub struct YourObject {
    /// Base data for object storage (REQUIRED)
    pub base_data: BaseData,
    
    /// Your custom fields
    pub title: String,
    pub status: YourStatus,
    // ... other fields
}
```

**Required traits:**
- `Debug` - for debugging
- `Clone` - required by Object trait
- `Serialize, Deserialize` - for JSON serialization
- `PartialEq` - for comparisons
- `crate::DeriveObject` - **CRITICAL** - auto-implements Object trait

**Required field:**
- `base_data: BaseData` - MUST be present for object storage

### 3. Implement Constructor and Methods

```rust
impl YourObject {
    /// Create a new object
    pub fn new(id: u32) -> Self {
        let base_data = BaseData::with_id(id, String::new());
        Self {
            base_data,
            title: String::new(),
            status: YourStatus::default(),
            // ... initialize other fields
        }
    }
    
    /// Fluent builder methods
    pub fn title(mut self, title: impl ToString) -> Self {
        self.title = title.to_string();
        self
    }
    
    // ... other methods
}
```

### 4. Create Rhai Bindings Module

Create `rhai.rs` in the same directory:

```rust
use ::rhai::plugin::*;
use ::rhai::{CustomType, Dynamic, Engine, EvalAltResult, Module, TypeBuilder};

use super::{YourObject, YourStatus};

/// Register your modules with the Rhai engine
pub fn register_your_modules(parent_module: &mut Module) {
    // Register custom types
    parent_module.set_custom_type::<YourObject>("YourObject");
    parent_module.set_custom_type::<YourStatus>("YourStatus");
    
    // Merge functions
    let your_module = exported_module!(rhai_your_module);
    parent_module.merge(&your_module);
}

#[export_module]
mod rhai_your_module {
    use super::YourObject;
    use ::rhai::EvalAltResult;
    
    // Constructor
    #[rhai_fn(name = "new_your_object", return_raw)]
    pub fn new_your_object(id: i64) -> Result<YourObject, Box<EvalAltResult>> {
        Ok(YourObject::new(id as u32))
    }
    
    // Builder methods
    #[rhai_fn(name = "title", return_raw)]
    pub fn set_title(
        obj: YourObject,
        title: String,
    ) -> Result<YourObject, Box<EvalAltResult>> {
        Ok(obj.title(title))
    }
    
    // Getters
    #[rhai_fn(name = "title", pure)]
    pub fn get_title(obj: &mut YourObject) -> String {
        obj.title.clone()
    }
}

// CustomType implementations
impl CustomType for YourObject {
    fn build(mut builder: TypeBuilder<Self>) {
        builder.with_name("YourObject");
    }
}

impl CustomType for YourStatus {
    fn build(mut builder: TypeBuilder<Self>) {
        builder.with_name("YourStatus");
    }
}
```

### 5. Update Module Exports

In `mod.rs` of your object category:

```rust
pub mod your_object;
pub mod rhai;

pub use your_object::{YourObject, YourStatus};
pub use rhai::register_your_modules;
```

In `src/objects/mod.rs`:

```rust
pub mod your_category;

pub use your_category::{YourObject, YourStatus};
```

### 6. Register in Engine (CRITICAL STEP)

In `src/engine.rs`, add the save registration in the `OsirisPackage` definition:

```rust
def_package! {
    pub OsirisPackage(module) : StandardPackage {
        // ... existing registrations ...
        
        // Add your object's save method
        FuncRegistration::new("save")
            .set_into_module(module, |ctx: &mut OsirisContext, obj: crate::objects::YourObject| ctx.save_object(obj));
        
        // ... existing registrations ...
        
        // Register your modules
        register_your_modules(module);
    }
}
```

Also add the import at the top of `engine.rs`:

```rust
use crate::objects::your_category::rhai::register_your_modules;
```

### 7. Create Example Script

Create `examples/engine/XX_your_object.rhai`:

```rhai
print("=== Your Object Example ===\n");

// Get context
let ctx = get_context(["alice", "bob"]);

// Create object
let obj = new_your_object(1)
    .title("Example Title");

print("Object created: " + obj.title());

// Store in context
ctx.save(obj);
print("Object stored");

print("\n=== Example Complete ===");
```

## Checklist

Before considering your object complete, verify:

- [ ] Struct derives `crate::DeriveObject`
- [ ] Struct has `base_data: BaseData` field
- [ ] Rhai module created with `register_*_modules` function
- [ ] Custom types registered with `set_custom_type`
- [ ] Module exported in `mod.rs` files
- [ ] Save method registered in `src/engine.rs`
- [ ] Module registration added to `OsirisPackage` in `src/engine.rs`
- [ ] Example script created and tested
- [ ] Example runs successfully with `cargo run --example engine examples/engine/XX_your_object.rhai`

## Common Mistakes to Avoid

1. **Forgetting `crate::DeriveObject`** - Without this, the Object trait won't be implemented
2. **Missing `base_data` field** - Required for all storable objects
3. **Not registering save in engine.rs** - The save method MUST be in engine.rs, not context.rs
4. **Not calling `set_custom_type`** - Rhai won't recognize your type
5. **Not merging the exported module** - Your functions won't be available

## Example: Contract Object

See the Contract object implementation as a reference:
- Struct: `src/objects/legal/contract.rs`
- Rhai bindings: `src/objects/legal/rhai.rs`
- Module exports: `src/objects/legal/mod.rs` and `src/objects/mod.rs`
- Engine registration: `src/engine.rs` (line ~110 and ~138)
- Example: `examples/engine/12_contract.rhai`