# [DEF:backend/src/api/routes/llm.py:Module]
# @TIER: STANDARD
# @SEMANTICS: api, routes, llm
# @PURPOSE: API routes for LLM provider configuration and management.
# @LAYER: UI (API)

from fastapi import APIRouter, Depends, HTTPException, status
from typing import List, Optional
from ...core.logger import logger
from ...schemas.auth import User
from ...dependencies import get_current_user as get_current_active_user
from ...plugins.llm_analysis.models import LLMProviderConfig, LLMProviderType
from ...services.llm_provider import LLMProviderService
from ...core.database import get_db
from sqlalchemy.orm import Session

# [DEF:router:Global]
# @PURPOSE: APIRouter instance for LLM routes.
router = APIRouter(tags=["LLM"])
# [/DEF:router:Global]


# [DEF:_is_valid_runtime_api_key:Function]
# @PURPOSE: Validate decrypted runtime API key presence/shape.
# @PRE: value can be None.
# @POST: Returns True only for non-placeholder key.
def _is_valid_runtime_api_key(value: Optional[str]) -> bool:
    key = (value or "").strip()
    if not key:
        return False
    if key in {"********", "EMPTY_OR_NONE"}:
        return False
    return len(key) >= 16
# [/DEF:_is_valid_runtime_api_key:Function]

# [DEF:get_providers:Function]
# @PURPOSE: Retrieve all LLM provider configurations.
# @PRE: User is authenticated.
# @POST: Returns list of LLMProviderConfig.
@router.get("/providers", response_model=List[LLMProviderConfig])
async def get_providers(
    current_user: User = Depends(get_current_active_user),
    db: Session = Depends(get_db)
):
    """
    Get all LLM provider configurations.
    """
    logger.info(f"[llm_routes][get_providers][Action] Fetching providers for user: {current_user.username}")
    service = LLMProviderService(db)
    providers = service.get_all_providers()
    return [
        LLMProviderConfig(
            id=p.id,
            provider_type=LLMProviderType(p.provider_type),
            name=p.name,
            base_url=p.base_url,
            api_key="********",
            default_model=p.default_model,
            is_active=p.is_active
        ) for p in providers
    ]
# [/DEF:get_providers:Function]


# [DEF:get_llm_status:Function]
# @PURPOSE: Returns whether LLM runtime is configured for dashboard validation.
# @PRE: User is authenticated.
# @POST: configured=true only when an active provider with valid decrypted key exists.
@router.get("/status")
async def get_llm_status(
    current_user: User = Depends(get_current_active_user),
    db: Session = Depends(get_db)
):
    service = LLMProviderService(db)
    providers = service.get_all_providers()
    active_provider = next((p for p in providers if p.is_active), None)

    if not active_provider:
        return {"configured": False, "reason": "no_active_provider"}

    api_key = service.get_decrypted_api_key(active_provider.id)
    if not _is_valid_runtime_api_key(api_key):
        return {"configured": False, "reason": "invalid_api_key"}

    return {
        "configured": True,
        "reason": "ok",
        "provider_id": active_provider.id,
        "provider_name": active_provider.name,
        "provider_type": active_provider.provider_type,
        "default_model": active_provider.default_model,
    }
# [/DEF:get_llm_status:Function]

# [DEF:create_provider:Function]
# @PURPOSE: Create a new LLM provider configuration.
# @PRE: User is authenticated and has admin permissions.
# @POST: Returns the created LLMProviderConfig.
@router.post("/providers", response_model=LLMProviderConfig, status_code=status.HTTP_201_CREATED)
async def create_provider(
    config: LLMProviderConfig,
    current_user: User = Depends(get_current_active_user),
    db: Session = Depends(get_db)
):
    """
    Create a new LLM provider configuration.
    """
    service = LLMProviderService(db)
    provider = service.create_provider(config)
    return LLMProviderConfig(
        id=provider.id,
        provider_type=LLMProviderType(provider.provider_type),
        name=provider.name,
        base_url=provider.base_url,
        api_key="********",
        default_model=provider.default_model,
        is_active=provider.is_active
    )
# [/DEF:create_provider:Function]

# [DEF:update_provider:Function]
# @PURPOSE: Update an existing LLM provider configuration.
# @PRE: User is authenticated and has admin permissions.
# @POST: Returns the updated LLMProviderConfig.
@router.put("/providers/{provider_id}", response_model=LLMProviderConfig)
async def update_provider(
    provider_id: str,
    config: LLMProviderConfig,
    current_user: User = Depends(get_current_active_user),
    db: Session = Depends(get_db)
):
    """
    Update an existing LLM provider configuration.
    """
    service = LLMProviderService(db)
    provider = service.update_provider(provider_id, config)
    if not provider:
        raise HTTPException(status_code=404, detail="Provider not found")
    
    return LLMProviderConfig(
        id=provider.id,
        provider_type=LLMProviderType(provider.provider_type),
        name=provider.name,
        base_url=provider.base_url,
        api_key="********",
        default_model=provider.default_model,
        is_active=provider.is_active
    )
# [/DEF:update_provider:Function]

# [DEF:delete_provider:Function]
# @PURPOSE: Delete an LLM provider configuration.
# @PRE: User is authenticated and has admin permissions.
# @POST: Returns success status.
@router.delete("/providers/{provider_id}", status_code=status.HTTP_204_NO_CONTENT)
async def delete_provider(
    provider_id: str,
    current_user: User = Depends(get_current_active_user),
    db: Session = Depends(get_db)
):
    """
    Delete an LLM provider configuration.
    """
    service = LLMProviderService(db)
    if not service.delete_provider(provider_id):
        raise HTTPException(status_code=404, detail="Provider not found")
    return
# [/DEF:delete_provider:Function]

# [DEF:test_connection:Function]
# @PURPOSE: Test connection to an LLM provider.
# @PRE: User is authenticated.
# @POST: Returns success status and message.
@router.post("/providers/{provider_id}/test")
async def test_connection(
    provider_id: str,
    current_user: User = Depends(get_current_active_user),
    db: Session = Depends(get_db)
):
    logger.info(f"[llm_routes][test_connection][Action] Testing connection for provider_id: {provider_id}")
    """
    Test connection to an LLM provider.
    """
    from ...plugins.llm_analysis.service import LLMClient
    service = LLMProviderService(db)
    db_provider = service.get_provider(provider_id)
    if not db_provider:
        raise HTTPException(status_code=404, detail="Provider not found")
    
    api_key = service.get_decrypted_api_key(provider_id)
    
    # Check if API key was successfully decrypted
    if not api_key:
        logger.error(f"[llm_routes][test_connection] Failed to decrypt API key for provider {provider_id}")
        raise HTTPException(
            status_code=500,
            detail="Failed to decrypt API key. The provider may have been encrypted with a different encryption key. Please update the provider with a new API key."
        )
    
    client = LLMClient(
        provider_type=LLMProviderType(db_provider.provider_type),
        api_key=api_key,
        base_url=db_provider.base_url,
        default_model=db_provider.default_model
    )
    
    try:
        # Simple test call
        await client.client.models.list()
        return {"success": True, "message": "Connection successful"}
    except Exception as e:
        return {"success": False, "error": str(e)}
# [/DEF:test_connection:Function]

# [DEF:test_provider_config:Function]
# @PURPOSE: Test connection with a provided configuration (not yet saved).
# @PRE: User is authenticated.
# @POST: Returns success status and message.
@router.post("/providers/test")
async def test_provider_config(
    config: LLMProviderConfig,
    current_user: User = Depends(get_current_active_user)
):
    """
    Test connection with a provided configuration.
    """
    from ...plugins.llm_analysis.service import LLMClient
    logger.info(f"[llm_routes][test_provider_config][Action] Testing config for {config.name}")
    
    # Check if API key is provided
    if not config.api_key or config.api_key == "********":
        raise HTTPException(
            status_code=400,
            detail="API key is required for testing connection"
        )
    
    client = LLMClient(
        provider_type=config.provider_type,
        api_key=config.api_key,
        base_url=config.base_url,
        default_model=config.default_model
    )
    
    try:
        # Simple test call
        await client.client.models.list()
        return {"success": True, "message": "Connection successful"}
    except Exception as e:
        return {"success": False, "error": str(e)}
# [/DEF:test_provider_config:Function]

# [/DEF:backend/src/api/routes/llm.py]