import { z } from "zod";
import prisma from "~/server/utils/prisma";

// Query parameter validation schema
const jobsQuerySchema = z.object({
  page: z
    .string()
    .transform((val) => parseInt(val) || 1)
    .optional(),
  limit: z
    .string()
    .transform((val) => parseInt(val) || 10)
    .optional(),
});

export default defineEventHandler(async (event) => {
  try {
    // Parse and validate query parameters
    const queryParams = getQuery(event) || {};
    const params = jobsQuerySchema.parse(queryParams);

    // Build where clause for filtering failed jobs
    const where = {
      status: "failed",
    };

    // Get total count for pagination
    const total = await prisma.notification_queue.count({ where });

    // Calculate pagination metadata
    const totalPages = Math.ceil(total / params.limit);

    // Fetch failed jobs with relations
    const jobs = await prisma.notification_queue.findMany({
      where,
      select: {
        id: true,
        status: true,
        scheduled_for: true,
        attempts: true,
        max_attempts: true,
        last_attempt_at: true,
        error_message: true,
        created_at: true,
        notifications: {
          select: {
            id: true,
            title: true,
            type: true,
          },
        },
      },
      orderBy: {
        last_attempt_at: "desc",
      },
      skip: (params.page - 1) * params.limit,
      take: params.limit,
    });

    // Format jobs for response
    const formattedJobs = jobs.map((job) => {
      return {
        id: job.id,
        type: job.notifications?.type || "unknown",
        description: job.notifications?.title || "Failed Notification",
        status: job.status,
        attempts: job.attempts,
        maxAttempts: job.max_attempts,
        errorType: job.error_message ? getErrorType(job.error_message) : "Unknown Error",
        errorMessage: job.error_message || "No error message provided",
        failedAt: job.last_attempt_at ? new Date(job.last_attempt_at).toISOString() : null,
        nextRetry: "Manual retry required",
      };
    });

    return {
      success: true,
      data: {
        jobs: formattedJobs,
        pagination: {
          page: params.page,
          totalPages,
          totalItems: total,
          hasMore: params.page < totalPages,
        },
      },
    };
  } catch (error) {
    console.error("Error fetching failed jobs:", error);

    if (error.statusCode) {
      throw error;
    }

    throw createError({
      statusCode: 500,
      statusMessage: "Failed to fetch failed jobs",
      data: {
        error: error.message,
      },
    });
  } finally {
  }
});

// Helper function to extract error type from error message
function getErrorType(errorMessage) {
  if (!errorMessage) return "Unknown Error";
  
  if (errorMessage.includes("timeout")) return "Timeout Error";
  if (errorMessage.includes("connect")) return "Connection Error";
  if (errorMessage.includes("authentication")) return "Authentication Error";
  if (errorMessage.includes("rate limit")) return "Rate Limit Error";
  if (errorMessage.includes("validation")) return "Validation Error";
  if (errorMessage.includes("template")) return "Template Error";
  
  return "Processing Error";
}