"use server";

import { auth } from "@/auth";
import { db } from "@/lib/db";
import { hasPermission } from "@/lib/permissions";
import { z } from "zod";
import { revalidatePath } from "next/cache";

type ActionResult = { ok: true } | { error: string };

const vesselSchema = z.object({
  name: z.string().min(1, "Vessel name is required"),
  imoNumber: z.string().optional(),
});

export async function createVessel(formData: FormData): Promise<ActionResult> {
  const session = await auth();
  if (!session?.user || !hasPermission(session.user.role, "manage_vessels_accounts")) {
    return { error: "Unauthorized" };
  }

  const parsed = vesselSchema.safeParse({
    name: formData.get("name"),
    imoNumber: formData.get("imoNumber") || undefined,
  });
  if (!parsed.success) return { error: parsed.error.errors[0]?.message ?? "Validation failed" };

  const data = parsed.data;
  if (data.imoNumber) {
    const exists = await db.vessel.findUnique({ where: { imoNumber: data.imoNumber } });
    if (exists) return { error: "A vessel with that IMO number already exists" };
  }

  await db.vessel.create({ data: { name: data.name, imoNumber: data.imoNumber ?? null } });
  revalidatePath("/admin/vessels");
  return { ok: true };
}

export async function updateVessel(formData: FormData): Promise<ActionResult> {
  const session = await auth();
  if (!session?.user || !hasPermission(session.user.role, "manage_vessels_accounts")) {
    return { error: "Unauthorized" };
  }

  const id = formData.get("id") as string;
  if (!id) return { error: "Vessel ID is required" };

  const parsed = vesselSchema.safeParse({
    name: formData.get("name"),
    imoNumber: formData.get("imoNumber") || undefined,
  });
  if (!parsed.success) return { error: parsed.error.errors[0]?.message ?? "Validation failed" };

  const data = parsed.data;
  if (data.imoNumber) {
    const conflict = await db.vessel.findFirst({ where: { imoNumber: data.imoNumber, id: { not: id } } });
    if (conflict) return { error: "Another vessel already has that IMO number" };
  }

  await db.vessel.update({ where: { id }, data: { name: data.name, imoNumber: data.imoNumber ?? null } });
  revalidatePath("/admin/vessels");
  return { ok: true };
}

export async function deleteVessel(id: string): Promise<ActionResult> {
  const session = await auth();
  if (!session?.user || !hasPermission(session.user.role, "manage_vessels_accounts")) return { error: "Unauthorized" };

  const inUse = await db.purchaseOrder.findFirst({ where: { vesselId: id } });
  if (inUse) return { error: "Cannot delete: vessel is referenced in purchase orders. Remove those POs first." };

  await db.vessel.delete({ where: { id } });
  revalidatePath("/admin/vessels");
  return { ok: true };
}

export async function toggleVesselActive(vesselId: string): Promise<ActionResult> {
  const session = await auth();
  if (!session?.user || !hasPermission(session.user.role, "manage_vessels_accounts")) {
    return { error: "Unauthorized" };
  }

  const vessel = await db.vessel.findUnique({ where: { id: vesselId }, select: { isActive: true } });
  if (!vessel) return { error: "Vessel not found" };

  await db.vessel.update({ where: { id: vesselId }, data: { isActive: !vessel.isActive } });
  revalidatePath("/admin/vessels");
  return { ok: true };
}