import json
from datetime import datetime
from pydantic import BaseModel

class User(BaseModel):
    name: str
    created_at: datetime

user = User(name="Alice", created_at=datetime.now())

# ❌ Standard json fails
json.dumps(user)  # TypeError: Object of type User is not JSON serializable

import kajson

# ✅ Just works!
json_str = kajson.dumps(user)
restored_user = kajson.loads(json_str)
assert user == restored_user  # Perfect reconstruction!

from datetime import datetime
from pydantic import BaseModel
from kajson import kajson, kajson_manager

class User(BaseModel):
    name: str
    email: str
    created_at: datetime

def main():
    # Create and serialize
    user = User(
        name="Alice", 
        email="[email protected]", 
        created_at=datetime.now()
    )

    # Serialize to JSON
    json_str = kajson.dumps(user, indent=2)

    # Deserialize back
    restored_user = kajson.loads(json_str)
    assert user == restored_user  # ✅ Perfect reconstruction!

if __name__ == "__main__":
    kajson_manager.KajsonManager()
    main()

from datetime import datetime
from typing import Any, Dict, List
from pydantic import BaseModel

class Comment(BaseModel):
    author: str
    content: str
    created_at: datetime

class BlogPost(BaseModel):
    title: str
    content: str
    published_at: datetime
    comments: List[Comment]
    metadata: Dict[str, Any]

# Create complex nested structure
post = BlogPost(
    title="Introducing Kajson",
    content="A powerful JSON library...",
    published_at=datetime.now(),
    comments=[
        Comment(author="Alice", content="Great post!", created_at=datetime.now()),
        Comment(author="Bob", content="Very helpful", created_at=datetime.now())
    ],
    metadata={"views": 1000, "likes": 50}
)

# Serialize and deserialize - it just works!
json_str = kajson.dumps(post)
restored_post = kajson.loads(json_str)

# All nested objects are perfectly preserved
assert isinstance(restored_post.comments[0], Comment)
assert restored_post.comments[0].created_at.year == datetime.now().year

# Before
import json
data = json.dumps(my_object)  # Often fails with complex objects

# After  
import kajson as json  # Drop-in replacement!
data = json.dumps(my_object)  # Works with complex objects

import kajson
data = kajson.dumps(my_object)

from decimal import Decimal
from pathlib import Path
from typing import Any, Dict
import kajson

# Register Decimal support
def encode_decimal(value: Decimal) -> Dict[str, str]:
    return {"decimal": str(value)}

def decode_decimal(data: Dict[str, str]) -> Decimal:
    return Decimal(data["decimal"])

kajson.UniversalJSONEncoder.register(Decimal, encode_decimal)
kajson.UniversalJSONDecoder.register(Decimal, decode_decimal)

# Now Decimal works seamlessly
data = {"price": Decimal("19.99"), "tax": Decimal("1.50")}
json_str = kajson.dumps(data)
restored = kajson.loads(json_str)
assert restored["price"] == Decimal("19.99")  # ✅

# Register Path support
kajson.UniversalJSONEncoder.register(
    Path, 
    lambda p: {"path": str(p)}
)
kajson.UniversalJSONDecoder.register(
    Path, 
    lambda d: Path(d["path"])
)

# Path objects now work too!
config = {"home": Path.home(), "config": Path("/etc/myapp/config.json")}
restored_config = kajson.loads(kajson.dumps(config))

from typing import Any, Dict
from typing_extensions import override

class Vector:
    def __init__(self, x: float, y: float):
        self.x = x
        self.y = y
    
    def __json_encode__(self):
        """Called by Kajson during serialization"""
        return {"x": self.x, "y": self.y}
    
    @classmethod
    def __json_decode__(cls, data: Dict[str, Any]):
        """Called by Kajson during deserialization"""
        return cls(data["x"], data["y"])
    
    @override
    def __eq__(self, other: object) -> bool:
        if not isinstance(other, Vector):
            return False
        return self.x == other.x and self.y == other.y

# Works automatically!
vector = Vector(3.14, 2.71)
restored = kajson.loads(kajson.dumps(vector))
assert vector == restored

from datetime import datetime, timedelta
from typing import Any, Dict
from pydantic import BaseModel

class Task(BaseModel):
    name: str
    created_at: datetime
    duration: timedelta
    metadata: Dict[str, Any]

# Create mixed-type list
tasks = [
    Task(
        name="Data processing",
        created_at=datetime.now(),
        duration=timedelta(hours=2, minutes=30),
        metadata={"priority": "high", "cpu_cores": 8}
    ),
    {"raw_data": "Some plain dict"},
    datetime.now(),
    ["plain", "list", "items"],
]

# Kajson handles everything!
json_str = kajson.dumps(tasks)
restored_tasks = kajson.loads(json_str)

# Type checking shows proper reconstruction
assert isinstance(restored_tasks[0], Task)
assert isinstance(restored_tasks[0].duration, timedelta)
assert isinstance(restored_tasks[2], datetime)

from pydantic import BaseModel, Field

class Product(BaseModel):
    name: str
    price: float = Field(gt=0)  # Price must be positive

# Invalid data
json_str = '{"name": "Widget", "price": -10, "__class__": "Product", "__module__": "__main__"}'

try:
    product = kajson.loads(json_str)
except kajson.KajsonDecoderError as e:
    print(f"Validation failed: {e}")
    # Output: Validation failed: Could not instantiate pydantic BaseModel...

from kajson import kajson, kajson_manager
from kajson.kajson_manager import KajsonManager

# Simulate dynamic class creation (e.g., from network, workflow definition)
remote_class_definition = '''
from pydantic import BaseModel, Field

class RemoteTask(BaseModel):
    task_id: str
    name: str  
    priority: int = Field(default=1, ge=1, le=10)
'''

# Execute and create the class dynamically
remote_namespace = {}
exec(remote_class_definition, remote_namespace)
RemoteTask = remote_namespace["RemoteTask"]

# Set module to simulate it's not available locally
RemoteTask.__module__ = "remote.distributed.system"

# Create and serialize
task = RemoteTask(task_id="TASK_001", name="Process Data", priority=5)
json_str = kajson.dumps(task)

# Clear local definition (simulate distributed scenario)
del remote_namespace["RemoteTask"]

# Register in class registry for deserialization
registry = KajsonManager.get_class_registry()
registry.register_class(RemoteTask)

# Now deserialization works via class registry!
restored_task = kajson.loads(json_str)
assert restored_task.task_id == "TASK_001"

from pydantic import BaseModel

class Animal(BaseModel):
    name: str
    species: str

class Dog(Animal):
    breed: str
    is_good_boy: bool = True

class Pet(BaseModel):
    owner: str
    animal: Animal  # ← Field declared as base class

# Create pet with subclass instance
pet = Pet(
    owner="Alice",
    animal=Dog(name="Buddy", species="Canis lupus", breed="Golden Retriever")  # ← Actual subclass
)

# Serialize and deserialize
json_str = kajson.dumps(pet)
restored_pet = kajson.loads(json_str)

# Subclass type and attributes are perfectly preserved!
assert isinstance(restored_pet.animal, Dog)  # ✅ Still a Dog, not just Animal
assert restored_pet.animal.breed == "Golden Retriever"  # ✅ Subclass attributes preserved
assert restored_pet.animal.is_good_boy is True  # ✅ All fields intact