from typing import Optional, Dict, Any, List
from fastapi import APIRouter
from pydantic import BaseModel, Field
from app.services.dbt_service import compile_dbt_model

router = APIRouter(tags=["dbt"])


class DbtCompileRequest(BaseModel):
    model_name: str = Field(..., description="Name of the dbt model (e.g. silver_cems_emission_enriched)")
    layer: Optional[str] = Field("silver", description="Medallion layer (silver or gold)")
    query: str = Field(..., description="SQL / Jinja query text to compile and validate")
    test_configs: Optional[Dict[str, Any]] = Field(None, description="Shift-left quality tests (unique, not_null, accepted_values, contracts)")


class DbtCompileResponse(BaseModel):
    status: str
    valid: bool
    model_name: str
    layer: str
    compiled_sql: str
    schema_yml: str
    extracted_refs: List[str] = []
    extracted_sources: List[Dict[str, str]] = []
    warnings: List[str] = []
    errors: List[str] = []


@router.post("/dbt/compile", response_model=DbtCompileResponse)
def compile_dbt_model_endpoint(req: DbtCompileRequest):
    """
    Pre-flight compile and validation check for dbt models:
    - Validates Jinja expressions & delimiters.
    - Resolves ref() and source() bindings.
    - Emits compiled SQL and matching dbt schema.yml with test assertions.
    """
    res = compile_dbt_model(
        model_name=req.model_name,
        layer=req.layer or "silver",
        sql_query=req.query,
        test_configs=req.test_configs
    )
    return res