import { formulateQuestionForTarget } from "@/lib/graph/focused-investigation";

export async function POST(request) {
  try {
    const body = await request.json();

    if (!body.targetNodeId || typeof body.targetNodeId !== "string") {
      return Response.json(
        { error: "Request must include a 'targetNodeId' string field" },
        { status: 400 },
      );
    }

    if (!body.situationGraph || typeof body.situationGraph !== "object") {
      return Response.json(
        { error: "Request must include a 'situationGraph' object field" },
        { status: 400 },
      );
    }

    const result = formulateQuestionForTarget({
      situationGraph: body.situationGraph,
      targetNodeId: body.targetNodeId,
    });

    if (!result.success) {
      return Response.json(
        { success: false, error: result.error },
        { status: 400 },
      );
    }

    return Response.json({
      success: true,
      targetNodeId: result.targetNodeId,
      question: result.question,
      strategy: result.strategy,
      reasoningPattern: result.reasoningPattern,
      reasoningPatternReason: result.reasoningPatternReason,
      reason: result.reason,
      questionFamily: result.questionFamily,
      selectedQuestionTemplate: result.selectedQuestionTemplate,
      allowedQuestionFamilies: result.allowedQuestionFamilies,
      rejectedQuestionFamilies: result.rejectedQuestionFamilies,
    });
  } catch (e) {
    return Response.json(
      { error: e.message || "Unknown server error" },
      { status: 500 },
    );
  }
}