import { db } from "../src/lib/server/db/db";
import { tasks, taskTypes } from "../src/lib/server/db/schema/tasks";
import { faker } from "@faker-js/faker";
import logger from "../src/lib/server/logger";

async function resetDatabase() {
  logger.info("Resetting database...");
  // Delete in reverse order of creation to respect foreign key constraints
  await db.delete(tasks);
  await db.delete(taskTypes);
  logger.info("Database reset complete.");
}

async function seedDatabase(count: number) {
  logger.info(`Seeding database with ${count} tasks...`);

  // 1. Seed Task Types
  const insertedTaskTypes = await db.insert(taskTypes).values([
    { name: "Product Change", prefix: "PC" },
    { name: "Task", prefix: "TA" },
  ]).returning();
  logger.info(`Seeded ${insertedTaskTypes.length} task types.`);

  if (insertedTaskTypes.length === 0) {
    throw new Error("Task type seeding failed. Cannot seed tasks.");
  }

  // 2. Seed Tasks
  const newTasks = [];
  const usedTaskIds = new Set<number>();
  for (let i = 0; i < count; i++) {
    let randomId: number;
    do {
      randomId = Math.floor(100000 + Math.random() * 900000);
    } while (usedTaskIds.has(randomId));
    usedTaskIds.add(randomId);

    newTasks.push({
      // task_id with a guaranteed unique 6 digit number
      taskId: randomId.toString(),
      // a random phrase in each description
      description: faker.lorem.sentence(),
      // open_date with a valid date
      openDate: faker.date.recent({ days: 30 }).toISOString(),
      // a random paragraph in body
      body: faker.lorem.paragraphs(3),
      // other fields as needed
      type: faker.helpers.arrayElement(insertedTaskTypes).id,
      status: faker.helpers.arrayElement(["Todo", "In Progress", "Done", "Canceled"]),
      priority: faker.helpers.arrayElement(["Low", "Medium", "High", "Urgent"]),
    });
  }

  // 3. Insert the new tasks in chunks to avoid exceeding driver limits
  logger.info(`Inserting ${newTasks.length} tasks in chunks...`);
  const chunkSize = 500;
  let totalInserted = 0;
  for (let i = 0; i < newTasks.length; i += chunkSize) {
    const chunk = newTasks.slice(i, i + chunkSize);
    const inserted = await db.insert(tasks).values(chunk).returning();
    totalInserted += inserted.length;
    logger.info(`  ... inserted chunk ${Math.floor(i / chunkSize) + 1}, ${totalInserted}/${newTasks.length} tasks`);
  }
  logger.info(`Seeding complete. Total tasks inserted: ${totalInserted}.`);
}

async function main() {
  const mode = process.argv[2];

  // Default count if no flag is provided
  let count = 20;

  // Find and parse the --count flag
  const countArg = process.argv.find((arg) => arg.startsWith("--count="));
  if (countArg) {
    const countValue = parseInt(countArg.split("=")[1], 10);
    if (!isNaN(countValue) && countValue > 0) {
      count = countValue;
    }
  }

  if (mode === "reset") {
    await resetDatabase();
  } else if (mode === "seed") {
    // Seeding implies a reset first for a clean slate
    await resetDatabase();
    await seedDatabase(count);
  } else {
    logger.error('Invalid mode. Use "seed" or "reset".');
    process.exit(1);
  }

  logger.info("Script finished.");
}

main().catch((e) => {
  logger.error(e, "An error occurred during the script execution.");
  process.exit(1);
});