import { NextResponse } from "next/server";
import { z } from "zod";
import {
  AUTOTRADE_API_ERROR_CODE,
  createAutotradeErrorResponse,
  getAutotradeUserId,
  hasAutotradeKisRuntimeHeaders,
  readJsonBody,
  sanitizeAutotradeError,
  upsertAutotradeSession,
} from "@/app/api/autotrade/_shared";

const startRequestSchema = z.object({
  symbol: z.string().trim().regex(/^\d{6}$/),
  leaderTabId: z.string().trim().min(1).max(100),
  effectiveAllocationAmount: z.number().int().positive(),
  effectiveDailyLossLimit: z.number().int().positive(),
  strategySummary: z.string().trim().min(1).max(320),
});

export async function POST(request: Request) {
  const userId = await getAutotradeUserId(request.headers);
  if (!userId) {
    return createAutotradeErrorResponse({
      status: 401,
      code: AUTOTRADE_API_ERROR_CODE.AUTH_REQUIRED,
      message: "로그인이 필요합니다.",
    });
  }

  if (!hasAutotradeKisRuntimeHeaders(request.headers)) {
    return createAutotradeErrorResponse({
      status: 400,
      code: AUTOTRADE_API_ERROR_CODE.CREDENTIAL_REQUIRED,
      message: "자동매매 시작에는 KIS 인증 헤더가 필요합니다.",
    });
  }

  const rawBody = await readJsonBody(request);
  const parsed = startRequestSchema.safeParse(rawBody);
  if (!parsed.success) {
    return createAutotradeErrorResponse({
      status: 400,
      code: AUTOTRADE_API_ERROR_CODE.INVALID_REQUEST,
      message: parsed.error.issues[0]?.message ?? "세션 시작 입력값이 올바르지 않습니다.",
    });
  }

  try {
    const now = new Date().toISOString();
    const session = upsertAutotradeSession({
      userId,
      sessionId: crypto.randomUUID(),
      symbol: parsed.data.symbol,
      runtimeState: "RUNNING",
      leaderTabId: parsed.data.leaderTabId,
      startedAt: now,
      lastHeartbeatAt: now,
      endedAt: null,
      stopReason: null,
      effectiveAllocationAmount: parsed.data.effectiveAllocationAmount,
      effectiveDailyLossLimit: parsed.data.effectiveDailyLossLimit,
      strategySummary: parsed.data.strategySummary,
    });

    return NextResponse.json({
      ok: true,
      session,
    });
  } catch (error) {
    return createAutotradeErrorResponse({
      status: 500,
      code: AUTOTRADE_API_ERROR_CODE.INTERNAL,
      message: sanitizeAutotradeError(error, "자동매매 세션 시작 중 오류가 발생했습니다."),
    });
  }
}