import { generateText } from "ai";
import { NextRequest, NextResponse } from "next/server";
import { z } from "zod";
import { createLogger } from "@/lib/observability/logger";
import { buildProductPlanningAnalyzePrompt } from "@/lib/product-planning/analyze";
import { resolveProductPlanningTextModel } from "@/lib/product-planning/model-runtime";
import {
  isProductPlanningEnabled,
  PRODUCT_PLANNING_DISABLED_MESSAGE,
} from "@/lib/product-planning/server-feature";
import { getProductPlanningToken } from "@/lib/product-planning/server-auth";
import type {
  ProductPlanningAnalyzeRequest,
  ProductPlanningAnalyzeResponse,
} from "@/lib/product-planning/types";

export const runtime = "nodejs";
export const maxDuration = 120;

const logger = createLogger("product-planning-analyze-api");

const requestSchema = z.union([
  z.object({
    kind: z.literal("review"),
    rows: z
      .array(
        z.object({
          itemId: z.string(),
          date: z.string(),
          content: z.string(),
          appendComment: z.string().optional(),
          sku: z.string().optional(),
          userId: z.string().optional(),
          images: z.array(z.string()),
          videoUrls: z.array(z.string()),
        })
      )
      .min(1),
  }),
  z.object({
    kind: z.literal("qa"),
    rows: z
      .array(
        z.object({
          itemId: z.string(),
          question: z.string(),
          questionDetail: z.string().optional(),
          answer: z.string(),
          answerUser: z.string().optional(),
          answerDate: z.string().optional(),
          isOfficial: z.boolean(),
        })
      )
      .min(1),
  }),
]);

function jsonError(status: number, error: string) {
  const payload: ProductPlanningAnalyzeResponse = {
    success: false,
    error,
  };
  return NextResponse.json(payload, { status });
}

export async function POST(request: NextRequest) {
  const token = await getProductPlanningToken(request);
  if (!token?.sub) {
    return jsonError(401, "未登录");
  }
  if (!(await isProductPlanningEnabled())) {
    return jsonError(403, PRODUCT_PLANNING_DISABLED_MESSAGE);
  }

  let body: unknown;
  try {
    body = await request.json();
  } catch {
    return jsonError(400, "请求体不是合法 JSON");
  }

  const parsed = requestSchema.safeParse(body);
  if (!parsed.success) {
    return jsonError(400, "请求参数不合法或 rows 为空");
  }

  const resolvedModel = await resolveProductPlanningTextModel();
  if (!resolvedModel.model) {
    return jsonError(500, resolvedModel.error || "当前站点没有可用的文本分析模型");
  }

  try {
    const analyzeRequest = parsed.data as ProductPlanningAnalyzeRequest;
    const prompt = buildProductPlanningAnalyzePrompt(analyzeRequest);
    const { text } = await generateText({
      model: resolvedModel.model,
      prompt,
      temperature: 0.3,
    });

    const payload: ProductPlanningAnalyzeResponse = {
      success: true,
      markdown: text,
    };
    return NextResponse.json(payload);
  } catch (error) {
    logger.error("request_failed", error);
    return jsonError(502, "AI 分析失败");
  }
}