import time

from schemas import CodeXRequest, CodeXResponse, CodeTaskType, ResponseMeta
from code_router import detect_task_type
from prompt_builder import build_prompt
from model_client import model_client
from response_formatter import build_response, build_error_response
from code_retriever import retrieve_code_evidence
from context_manager import context_manager
from scope_router import decide_scope, ScopeRoute
from config import settings


def should_use_retrieval(task_type: CodeTaskType, request: CodeXRequest) -> bool:
    if not request.use_retrieval:
        return False

    if task_type == CodeTaskType.FIX and settings.ENABLE_RETRIEVAL_FOR_FIX:
        return True

    if task_type == CodeTaskType.GENERATE and settings.ENABLE_RETRIEVAL_FOR_GENERATE:
        return True

    if task_type == CodeTaskType.EXPLAIN and settings.ENABLE_RETRIEVAL_FOR_EXPLAIN:
        return True

    return False


def get_retrieved_evidence(task_type: CodeTaskType, request: CodeXRequest):
    return retrieve_code_evidence(task_type, request)


def build_scope_response(
    route: ScopeRoute,
    message: str,
    processing_time_ms: int,
) -> CodeXResponse:
    warnings = []

    if route == ScopeRoute.RESTRICTED:
        warnings.append("Restricted or unsafe request detected.")
    elif route == ScopeRoute.IMAGE:
        warnings.append("Image-related request detected.")
    elif route == ScopeRoute.NON_CODE:
        warnings.append("Out-of-scope non-code request detected.")
    elif route == ScopeRoute.GREETING:
        warnings.append("Greeting request detected.")
    else:
        warnings.append("Unsupported or unclear request detected.")

    return CodeXResponse(
        answer=message,
        task_type=CodeTaskType.UNKNOWN,
        code_output=None,
        explanation=message,
        warnings=warnings,
        sources=[],
        needs_clarification=False,
        meta=ResponseMeta(
            used_model="scope_router",
            fallback_used=False,
            retrieval_used=False,
            source_count=0,
            processing_time_ms=processing_time_ms,
        ),
    )


def process_codex_request(request: CodeXRequest) -> CodeXResponse:
    start_time = time.perf_counter()

    try:
        scope_decision = decide_scope(request)
        if not scope_decision.should_continue_to_codex:
            processing_time_ms = int((time.perf_counter() - start_time) * 1000)
            return build_scope_response(
                route=scope_decision.route,
                message=scope_decision.message,
                processing_time_ms=processing_time_ms,
            )

        enriched_request = context_manager.enrich_request_with_context(
            request=request,
            session_id=request.session_id,
        )

        task_type = detect_task_type(
            message=enriched_request.message,
            code=enriched_request.code,
            error_message=enriched_request.error_message,
            mode_hint=enriched_request.mode,
        )

        evidence_list = []
        retrieval_used = False

        if should_use_retrieval(task_type, enriched_request):
            evidence_list = get_retrieved_evidence(task_type, enriched_request)
            retrieval_used = len(evidence_list) > 0

        prompt = build_prompt(
            task_type=task_type,
            message=enriched_request.message,
            code=enriched_request.code,
            error_message=enriched_request.error_message,
            language=enriched_request.language,
            framework=enriched_request.framework,
            previous_context=enriched_request.previous_context,
            evidence_list=evidence_list,
        )

        model_output, model_used, used_fallback = model_client.generate(prompt)

        processing_time_ms = int((time.perf_counter() - start_time) * 1000)

        response = build_response(
            task_type=task_type,
            model_output=model_output,
            model_used=model_used,
            used_fallback=used_fallback,
            retrieval_used=retrieval_used,
            source_count=len(evidence_list),
            processing_time_ms=processing_time_ms,
            original_code=enriched_request.code,
            sources=evidence_list,
        )

        if response.code_output and response.code_output.strip():
            context_manager.save_artifact(
                session_id=enriched_request.session_id,
                code=response.code_output,
                task_type=task_type,
                language=enriched_request.language,
                framework=enriched_request.framework,
                last_user_goal=enriched_request.message,
            )

        return response

    except Exception as e:
        processing_time_ms = int((time.perf_counter() - start_time) * 1000)
        fallback_task = request.mode if request.mode else CodeTaskType.UNKNOWN

        return build_error_response(
            task_type=fallback_task,
            error_message=str(e),
            processing_time_ms=processing_time_ms,
        )