from typing import Any, Dict
from sqlalchemy import text
from app.db_sql import db
from app.ae_obj_types_def import obj_type_kv_li

def get_object_schema_info(obj_type: str, view: str = 'default', variant: str = 'base') -> Dict[str, Any]:
    """
    Introspects an object type to return its database and model structure.
    
    Args:
        obj_type: The name of the object (e.g., 'person').
        view: The SQL view to describe (default, detail, etc.).
        variant: The model variant to describe (base, in, out).
        
    Returns:
        A dictionary containing database column info and Pydantic field info.
    """
    if obj_type not in obj_type_kv_li:
        return {"error": f"Object type '{obj_type}' not found."}

    obj_cfg = obj_type_kv_li[obj_type]
    table_name = obj_cfg.get(f'tbl_{view}', obj_cfg.get('tbl_default', obj_cfg.get('tbl')))
    model_key = f'mdl_{variant}' if variant != 'base' else 'mdl'
    model = obj_cfg.get(model_key, obj_cfg.get('mdl_default', obj_cfg.get('mdl')))

    if not table_name:
        return {"error": f"Table configuration for '{obj_type}' is missing."}

    schema_info = {
        "object_type": obj_type,
        "view": view,
        "variant": variant,
        "database": {"table_name": table_name, "columns": []},
        "model": {"name": model.__name__ if hasattr(model, '__name__') else str(model), "fields": {}}
    }

    # 1. Database Introspection
    try:
        db_result = db.execute(text(f"DESCRIBE `{table_name}`"))
        for row in db_result.fetchall():
            schema_info["database"]["columns"].append({
                "field": row[0], "type": row[1], "nullable": row[2] == 'YES',
                "key": row[3], "default": row[4], "extra": row[5]
            })
    except Exception as e:
        schema_info["database"]["error"] = str(e)

    # 2. Pydantic Model Introspection
    if model and hasattr(model, "__fields__"):
        for field_name, field in model.__fields__.items():
            field_info = {
                "alias": field.alias, 
                "type": str(field.outer_type_), 
                "required": field.required, 
                "default": field.default
            }
            if field.field_info.description: 
                field_info["description"] = field.field_info.description
            schema_info["model"]["fields"][field_name] = field_info

    return schema_info