import { requireOwner, withCors, preflight } from "@/lib/admin";
import { sql } from "@/lib/db";
import { isApprovalStatus } from "@/lib/driver";

export async function OPTIONS(request: Request) {
  return preflight(request);
}

type DriverBody = {
  first_name?: string;
  last_name?: string;
  profile_image_url?: string;
  car_image_url?: string;
  car_seats?: number;
  rating?: number;
  /** Vetting decision: 'approved' | 'rejected' | 'suspended' | 'pending'. */
  approval_status?: string;
  /** Shown to the driver when the decision is 'rejected'. */
  rejection_reason?: string;
};

export async function PATCH(request: Request, { id }: { id: string }) {
  const auth = await requireOwner(request);
  if ("error" in auth) return withCors(request, auth.error);

  try {
    const body = (await request.json()) as DriverBody;

    // Vetting decision. Anything other than 'approved' also forces the driver
    // offline in the same statement: a driver who is suspended mid-shift must
    // stop receiving offers immediately, not at their next toggle.
    let approval: string | null = null;
    if (body.approval_status !== undefined) {
      if (!isApprovalStatus(body.approval_status)) {
        return withCors(
          request,
          Response.json(
            {
              error:
                "approval_status must be pending, approved, rejected or suspended.",
            },
            { status: 400 },
          ),
        );
      }

      if (body.approval_status === "rejected" && !body.rejection_reason?.trim()) {
        return withCors(
          request,
          Response.json(
            { error: "A rejection needs a reason the driver can act on." },
            { status: 400 },
          ),
        );
      }

      approval = body.approval_status;
    }

    const rejectionReason =
      approval === "approved" ? null : (body.rejection_reason?.trim() ?? null);

    const rows = await sql`
      UPDATE drivers SET
        first_name = COALESCE(${body.first_name ?? null}, first_name),
        last_name = COALESCE(${body.last_name ?? null}, last_name),
        profile_image_url = COALESCE(${body.profile_image_url ?? null}, profile_image_url),
        car_image_url = COALESCE(${body.car_image_url ?? null}, car_image_url),
        car_seats = COALESCE(${body.car_seats ?? null}, car_seats),
        rating = COALESCE(${body.rating ?? null}, rating),
        approval_status = COALESCE(${approval}, approval_status),
        rejection_reason = CASE
          WHEN ${approval}::text IS NULL THEN rejection_reason
          ELSE ${rejectionReason}
        END,
        reviewed_at = CASE
          WHEN ${approval}::text IS NULL THEN reviewed_at
          ELSE CURRENT_TIMESTAMP
        END,
        reviewed_by = CASE
          WHEN ${approval}::text IS NULL THEN reviewed_by
          ELSE ${auth.userId}::uuid
        END,
        online = CASE
          WHEN ${approval}::text IS NOT NULL AND ${approval}::text <> 'approved'
            THEN FALSE
          ELSE online
        END
      WHERE id = ${id}
      RETURNING *
    `;

    if (!rows[0]) {
      return withCors(request,
        Response.json({ error: "Driver not found." }, { status: 404 }),
      );
    }

    return withCors(request, Response.json({ data: rows[0] }));
  } catch (error) {
    console.error("[ADMIN_DRIVER_PATCH]: ", error);
    return withCors(request,
      Response.json({ error: "Internal Server Error" }, { status: 500 }),
    );
  }
}

export async function DELETE(request: Request, { id }: { id: string }) {
  const auth = await requireOwner(request);
  if ("error" in auth) return withCors(request, auth.error);

  try {
    const used = await sql<{ n: number }>`
      SELECT COUNT(*)::int AS n FROM rides WHERE driver_id = ${id}
    `;

    if (used[0].n > 0) {
      return withCors(request,
        Response.json(
          { error: "Driver has recorded rides and cannot be deleted." },
          { status: 409 },
        ),
      );
    }

    const rows = await sql`
      DELETE FROM drivers WHERE id = ${id} RETURNING id
    `;

    if (!rows[0]) {
      return withCors(request,
        Response.json({ error: "Driver not found." }, { status: 404 }),
      );
    }

    return withCors(request, Response.json({ data: rows[0] }));
  } catch (error) {
    console.error("[ADMIN_DRIVER_DELETE]: ", error);
    return withCors(request,
      Response.json({ error: "Internal Server Error" }, { status: 500 }),
    );
  }
}