import { getAuth } from "@clerk/react-router/server";
import { database } from "~/database/context";
import * as schema from "~/database/schema";
import { eq, and, gte } from "drizzle-orm";
import { isCommissioner } from "~/models/commissioner";
import { getSocketIO } from "../../../server/socket";
import { logger } from "~/lib/logger";

import type { ActionFunctionArgs } from "react-router";
export async function action(args: ActionFunctionArgs) {
  const { request } = args;
  const { userId } = await getAuth(args);

  if (!userId) {
    return Response.json({ error: "Unauthorized" }, { status: 401 });
  }

  const formData = await request.formData();
  const seasonId = formData.get("seasonId") as string;
  const pickNumber = parseInt(formData.get("pickNumber") as string);

  if (!seasonId || isNaN(pickNumber) || pickNumber < 1) {
    return Response.json({ error: "Missing required fields" }, { status: 400 });
  }

  const db = database();

  const season = await db.query.seasons.findFirst({
    where: eq(schema.seasons.id, seasonId),
  });

  if (!season) {
    return Response.json({ error: "Season not found" }, { status: 404 });
  }

  if (!(await isCommissioner(season.leagueId, userId))) {
    return Response.json({ error: "Only commissioners can roll back the draft" }, { status: 403 });
  }

  if (season.status !== "draft") {
    return Response.json(
      { error: "Cannot roll back a draft that is not in progress" },
      { status: 400 }
    );
  }

  const draftSlots = await db.query.draftSlots.findMany({
    where: eq(schema.draftSlots.seasonId, seasonId),
    orderBy: schema.draftSlots.draftOrder,
  });

  const totalTeams = draftSlots.length;

  if (totalTeams === 0) {
    return Response.json({ error: "No draft slots found for this season" }, { status: 400 });
  }

  // Calculate which team is on the clock at the rollback pick (snake draft)
  const round = Math.ceil(pickNumber / totalTeams);
  const isEvenRound = round % 2 === 0;
  let pickInRound = ((pickNumber - 1) % totalTeams) + 1;
  if (isEvenRound) {
    pickInRound = totalTeams - pickInRound + 1;
  }
  const rollbackSlot = draftSlots.find((slot) => slot.draftOrder === pickInRound);

  // Delete picks from pickNumber onwards
  await db
    .delete(schema.draftPicks)
    .where(
      and(
        eq(schema.draftPicks.seasonId, seasonId),
        gte(schema.draftPicks.pickNumber, pickNumber)
      )
    );

  // Update season: reset pick number and unpause
  await db
    .update(schema.seasons)
    .set({
      currentPickNumber: pickNumber,
      draftPaused: false,
    })
    .where(eq(schema.seasons.id, seasonId));

  // Emit socket events
  try {
    const io = getSocketIO();

    io.to(`draft-${seasonId}`).emit("draft-rolled-back", {
      seasonId,
      pickNumber,
      teamId: rollbackSlot?.teamId,
    });
  } catch (error) {
    logger.error("Socket.IO error:", error);
  }

  return Response.json({ success: true, pickNumber });
}