"use client";

import { useMemo } from "react";
import { cn } from "@/lib/utils";

interface Player {
  id: string;
  firstName: string;
  lastName: string;
  level?: string | null;
}

interface Match {
  id: string;
  round: number;
  position: number;
  status: string;
  team1Players: string[];
  team2Players: string[];
  team1Score: number[] | null;
  team2Score: number[] | null;
  winnerId: string | null;
  scheduledAt: string | null;
  court: {
    id: string;
    name: string;
  } | null;
}

interface BracketViewProps {
  matches: Match[];
  players: Map<string, Player>;
  onMatchClick?: (match: Match) => void;
}

const statusColors: Record<string, string> = {
  SCHEDULED: "bg-gray-50 border-gray-300",
  IN_PROGRESS: "bg-blue-50 border-blue-400",
  COMPLETED: "bg-green-50 border-green-300",
  CANCELLED: "bg-red-50 border-red-300",
  WALKOVER: "bg-yellow-50 border-yellow-300",
};

function getRoundName(round: number, totalRounds: number): string {
  const roundsFromEnd = totalRounds - round + 1;
  switch (roundsFromEnd) {
    case 1:
      return "Final";
    case 2:
      return "Semifinal";
    case 3:
      return "Cuartos";
    case 4:
      return "Octavos";
    case 5:
      return "Dieciseisavos";
    default:
      return `Ronda ${round}`;
  }
}

function formatScore(scores: number[] | null): string {
  if (!scores || scores.length === 0) return "-";
  return scores.join("-");
}

function TeamSlot({
  playerIds,
  players,
  score,
  isWinner,
  isEmpty,
}: {
  playerIds: string[];
  players: Map<string, Player>;
  score: number[] | null;
  isWinner: boolean;
  isEmpty: boolean;
}) {
  if (isEmpty || playerIds.length === 0) {
    return (
      <div className="flex items-center justify-between px-3 py-2 bg-gray-100 text-gray-400 rounded text-sm italic">
        <span>TBD</span>
        <span>-</span>
      </div>
    );
  }

  const playerNames = playerIds
    .map((id) => {
      const player = players.get(id);
      if (!player) return "Desconocido";
      return `${player.firstName} ${player.lastName.charAt(0)}.`;
    })
    .join(" / ");

  return (
    <div
      className={cn(
        "flex items-center justify-between px-3 py-2 rounded text-sm transition-all",
        isWinner
          ? "bg-green-100 text-green-800 font-medium"
          : "bg-white text-primary-700"
      )}
    >
      <span className="truncate max-w-[140px]" title={playerNames}>
        {playerNames}
      </span>
      <span className={cn("font-mono", isWinner && "font-bold")}>
        {formatScore(score)}
      </span>
    </div>
  );
}

function MatchBox({
  match,
  players,
  onClick,
}: {
  match: Match;
  players: Map<string, Player>;
  onClick?: () => void;
}) {
  const team1IsWinner =
    match.winnerId && match.team1Players.includes(match.winnerId);
  const team2IsWinner =
    match.winnerId && match.team2Players.includes(match.winnerId);

  const isClickable =
    match.status !== "COMPLETED" &&
    match.status !== "WALKOVER" &&
    match.team1Players.length > 0 &&
    match.team2Players.length > 0;

  return (
    <div
      className={cn(
        "w-[220px] rounded-lg border-2 overflow-hidden shadow-sm",
        statusColors[match.status] || statusColors.SCHEDULED,
        isClickable && "cursor-pointer hover:shadow-md hover:border-primary-400 transition-all"
      )}
      onClick={isClickable ? onClick : undefined}
    >
      {/* Match Info Header */}
      <div className="px-2 py-1 bg-white/50 border-b text-xs text-primary-500 flex justify-between">
        <span>Partido {match.position}</span>
        {match.court && <span>{match.court.name}</span>}
      </div>

      {/* Teams */}
      <div className="p-2 space-y-1">
        <TeamSlot
          playerIds={match.team1Players}
          players={players}
          score={match.team1Score}
          isWinner={!!team1IsWinner}
          isEmpty={match.team1Players.length === 0}
        />
        <div className="text-center text-xs text-primary-400">vs</div>
        <TeamSlot
          playerIds={match.team2Players}
          players={players}
          score={match.team2Score}
          isWinner={!!team2IsWinner}
          isEmpty={match.team2Players.length === 0}
        />
      </div>

      {/* Status */}
      <div className="px-2 py-1 text-center">
        <span
          className={cn(
            "text-xs px-2 py-0.5 rounded-full",
            match.status === "SCHEDULED" && "bg-gray-200 text-gray-600",
            match.status === "IN_PROGRESS" && "bg-blue-200 text-blue-700",
            match.status === "COMPLETED" && "bg-green-200 text-green-700",
            match.status === "WALKOVER" && "bg-yellow-200 text-yellow-700",
            match.status === "CANCELLED" && "bg-red-200 text-red-700"
          )}
        >
          {match.status === "SCHEDULED" && "Programado"}
          {match.status === "IN_PROGRESS" && "En Juego"}
          {match.status === "COMPLETED" && "Finalizado"}
          {match.status === "WALKOVER" && "Walkover"}
          {match.status === "CANCELLED" && "Cancelado"}
        </span>
      </div>
    </div>
  );
}

export function BracketView({ matches, players, onMatchClick }: BracketViewProps) {
  // Group matches by round
  const matchesByRound = useMemo(() => {
    const grouped = new Map<number, Match[]>();
    matches.forEach((match) => {
      const roundMatches = grouped.get(match.round) || [];
      roundMatches.push(match);
      grouped.set(match.round, roundMatches);
    });
    // Sort matches in each round by position
    grouped.forEach((roundMatches) => {
      roundMatches.sort((a, b) => a.position - b.position);
    });
    return grouped;
  }, [matches]);

  const totalRounds = Math.max(...Array.from(matchesByRound.keys()), 0);
  const rounds = Array.from({ length: totalRounds }, (_, i) => i + 1);

  if (matches.length === 0) {
    return (
      <div className="flex items-center justify-center h-64 text-primary-500">
        <div className="text-center">
          <svg
            className="w-12 h-12 mx-auto mb-3 text-primary-300"
            fill="none"
            stroke="currentColor"
            viewBox="0 0 24 24"
          >
            <path
              strokeLinecap="round"
              strokeLinejoin="round"
              strokeWidth={2}
              d="M9 5H7a2 2 0 00-2 2v12a2 2 0 002 2h10a2 2 0 002-2V7a2 2 0 00-2-2h-2M9 5a2 2 0 002 2h2a2 2 0 002-2M9 5a2 2 0 012-2h2a2 2 0 012 2"
            />
          </svg>
          <p>No hay bracket generado</p>
          <p className="text-sm mt-1">Genera el bracket para comenzar el torneo</p>
        </div>
      </div>
    );
  }

  return (
    <div className="overflow-x-auto pb-4">
      <div className="flex gap-8 min-w-max p-4">
        {rounds.map((round) => {
          const roundMatches = matchesByRound.get(round) || [];
          const roundName = getRoundName(round, totalRounds);

          // Calculate vertical spacing for bracket alignment
          const matchesInPreviousRound = round > 1 ? matchesByRound.get(round - 1)?.length || 0 : roundMatches.length * 2;
          const spacingMultiplier = Math.pow(2, round - 1);

          return (
            <div key={round} className="flex flex-col">
              {/* Round Header */}
              <div className="text-center mb-4">
                <h3 className="font-semibold text-primary-800">{roundName}</h3>
                <p className="text-xs text-primary-500">
                  {roundMatches.length} {roundMatches.length === 1 ? "partido" : "partidos"}
                </p>
              </div>

              {/* Matches */}
              <div
                className="flex flex-col justify-around flex-1"
                style={{
                  gap: `${(spacingMultiplier - 1) * 100 + 24}px`,
                  paddingTop: `${(spacingMultiplier - 1) * 50}px`,
                }}
              >
                {roundMatches.map((match) => (
                  <MatchBox
                    key={match.id}
                    match={match}
                    players={players}
                    onClick={() => onMatchClick?.(match)}
                  />
                ))}
              </div>
            </div>
          );
        })}
      </div>

      {/* Legend */}
      <div className="flex flex-wrap gap-4 justify-center mt-6 pt-4 border-t border-primary-200">
        <div className="flex items-center gap-2 text-xs">
          <div className="w-4 h-4 rounded bg-gray-200 border border-gray-300" />
          <span>Programado</span>
        </div>
        <div className="flex items-center gap-2 text-xs">
          <div className="w-4 h-4 rounded bg-blue-200 border border-blue-400" />
          <span>En Juego</span>
        </div>
        <div className="flex items-center gap-2 text-xs">
          <div className="w-4 h-4 rounded bg-green-200 border border-green-300" />
          <span>Finalizado</span>
        </div>
        <div className="flex items-center gap-2 text-xs">
          <div className="w-4 h-4 rounded bg-yellow-200 border border-yellow-300" />
          <span>Walkover</span>
        </div>
      </div>
    </div>
  );
}