import { useValidatedBody, useValidatedParams, z, zh } from 'h3-zod';
import prisma from '~~/lib/prisma';

export default defineEventHandler(async (event) => {
  const user = await requireUserSession(event);

  const userId = user.user.id;
  const { huntId, questId } = await useValidatedParams(
    event,
    z.object({
      huntId: zh.numAsString,
      questId: zh.numAsString
    })
  );

  const { direction } = await useValidatedBody(
    event,
    z.object({
      direction: z.enum(['up', 'down'])
    })
  );

  // Verify membership and get quest
  const quest = await prisma.huntQuest.findUnique({
    where: {
      id: questId,
      huntId,
      hunt: {
        members: {
          some: {
            memberId: userId
          }
        }
      }
    },
    select: {
      id: true,
      order: true
    }
  });

  if (!quest) {
    throw createError({ statusCode: 404, statusMessage: 'Not found!' });
  }

  const targetOrder = direction === 'up' ? quest.order - 1 : quest.order + 1;

  if (targetOrder < 0) {
    throw createError({ statusCode: 400, statusMessage: 'Already at top!' });
  }

  // Find the quest to swap with
  const swapQuest = await prisma.huntQuest.findFirst({
    where: {
      huntId,
      order: targetOrder
    },
    select: {
      id: true,
      order: true
    }
  });

  if (!swapQuest) {
    throw createError({ statusCode: 400, statusMessage: 'Already at bottom!' });
  }

  // Swap orders in a transaction
  await prisma.$transaction([
    prisma.huntQuest.update({
      where: { id: quest.id },
      data: { order: swapQuest.order }
    }),
    prisma.huntQuest.update({
      where: { id: swapQuest.id },
      data: { order: quest.order }
    })
  ]);

  return { success: true };
});