import { LitElement, html } from "lit";
import { customElement, state } from "lit/decorators.js";
import { generateID } from "../core/Util";
import { JoinLobbyEvent } from "./Main";
import { translateText } from "./Utils";
import { getApiBase, getUserMe, isLoggedIn } from "./jwt";

type QueueType = "ranked" | "unranked";
type GameMode = "ffa" | "team";

interface QueueStatus {
  queueSize: number;
  estimatedWaitTime?: number;
  position?: number;
}

interface LeaderboardEntry {
  rank: number;
  username: string;
  currentElo: number;
  gamesPlayed: number;
  wins: number;
  losses: number;
}

@customElement("ranked-queue")
export class RankedQueue extends LitElement {
  @state() private inQueue: boolean = false;
  @state() private queueType: QueueType = "ranked";
  @state() private gameMode: GameMode = "ffa";
  @state() private queueStatus: QueueStatus | null = null;
  @state() private playerElo: number | null = null;
  @state() private isConnecting: boolean = false;
  @state() private error: string | null = null;
  @state() private isLoadingElo: boolean = false;
  @state() private leaderboard: LeaderboardEntry[] = [];
  @state() private isLoadingLeaderboard: boolean = false;
  @state() private showLeaderboard: boolean = false;

  private ws: WebSocket | null = null;
  private clientID: string = generateID();
  private reconnectAttempts: number = 0;
  private maxReconnectAttempts: number = 3;
  private reconnectTimeout: number | null = null;

  createRenderRoot() {
    return this;
  }

  async connectedCallback() {
    super.connectedCallback();
    // Fetch player ELO and leaderboard immediately when component loads
    await Promise.all([this.fetchPlayerElo(), this.fetchLeaderboard()]);
  }

  disconnectedCallback() {
    super.disconnectedCallback();
    this.cleanup();
  }

  /**
   * Fetch player's ELO rating from /users/@me endpoint
   */
  private async fetchPlayerElo() {
    this.isLoadingElo = true;
    try {
      const userMe = await getUserMe();
      if (userMe !== false && userMe.player.elo !== undefined) {
        this.playerElo = userMe.player.elo;
      }
    } catch (error) {
      console.error("Failed to fetch player ELO:", error);
    } finally {
      this.isLoadingElo = false;
    }
  }

  /**
   * Fetch leaderboard via HTTP API
   */
  private async fetchLeaderboard() {
    this.isLoadingLeaderboard = true;
    try {
      const apiBase = getApiBase();
      const response = await fetch(`${apiBase}/leaderboard/public/ffa`);

      if (response.ok) {
        const data = await response.json();
        // Add rank to each entry
        this.leaderboard = data.map((entry: any, index: number) => ({
          rank: index + 1,
          username: entry.username ?? "Anonymous",
          currentElo: entry.currentElo,
          gamesPlayed: entry.gamesPlayed,
          wins: entry.wins,
          losses: entry.losses,
        }));
        console.log("Fetched leaderboard:", this.leaderboard.length, "players");
      }
    } catch (error) {
      console.error("Failed to fetch leaderboard:", error);
      // Don't show error to user, just silently fail
    } finally {
      this.isLoadingLeaderboard = false;
    }
  }

  private cleanup() {
    if (this.reconnectTimeout !== null) {
      clearTimeout(this.reconnectTimeout);
      this.reconnectTimeout = null;
    }
    if (this.ws) {
      this.ws.close();
      this.ws = null;
    }
  }

  private async connectWebSocket() {
    if (this.ws && this.ws.readyState === WebSocket.OPEN) {
      return; // Already connected
    }

    this.isConnecting = true;
    this.error = null;

    try {
      // Get authentication information
      const loginResult = isLoggedIn();
      if (loginResult === false) {
        throw new Error("Please log in to join ranked matchmaking");
      }

      const token = loginResult.token;

      // Determine WebSocket URL based on environment
      // In development, use local matchmaking server; in production, use API
      const matchmakingBase = process?.env?.MATCHMAKING_WS_URL;
      const wsUrl = matchmakingBase
        ? `${matchmakingBase}/matchmaking/join`
        : (() => {
            const apiBase = getApiBase();
            const protocol = apiBase.startsWith("https://") ? "wss:" : "ws:";
            const host = apiBase.replace(/^https?:\/\//, "");
            return `${protocol}//${host}/matchmaking/join`;
          })();

      console.log("Connecting to matchmaking WebSocket:", wsUrl);
      this.ws = new WebSocket(wsUrl);

      this.ws.onopen = () => {
        console.log("Connected to matchmaking service");
        this.isConnecting = false;
        this.reconnectAttempts = 0;

        // Send authentication message
        this.ws?.send(
          JSON.stringify({
            type: "auth",
            playToken: token,
            queueType: this.queueType,
            gameMode: this.gameMode,
          }),
        );
      };

      this.ws.onmessage = (event) => {
        try {
          const message = JSON.parse(event.data);
          this.handleMessage(message);
        } catch (error) {
          console.error("Error parsing WebSocket message:", error);
        }
      };

      this.ws.onerror = (error) => {
        console.error("WebSocket error:", error);
        this.error = "Connection error. Please try again.";
        this.isConnecting = false;
      };

      this.ws.onclose = () => {
        console.log("WebSocket closed");
        this.ws = null;

        // Attempt reconnection if we were in queue
        if (
          this.inQueue &&
          this.reconnectAttempts < this.maxReconnectAttempts
        ) {
          this.reconnectAttempts++;
          console.log(
            `Attempting reconnection ${this.reconnectAttempts}/${this.maxReconnectAttempts}`,
          );
          this.reconnectTimeout = window.setTimeout(
            () => this.connectWebSocket(),
            2000 * this.reconnectAttempts,
          );
        } else if (this.inQueue) {
          this.error = "Connection lost. Please rejoin the queue.";
          this.inQueue = false;
          this.isConnecting = false;
        }
      };
    } catch (error) {
      console.error("Error connecting to matchmaking:", error);
      this.error = error instanceof Error ? error.message : "Failed to connect";
      this.isConnecting = false;
    }
  }

  private handleMessage(message: any) {
    switch (message.type) {
      case "auth_success":
        console.log("Authentication successful");
        if (message.playerElo !== undefined) {
          this.playerElo = message.playerElo;
        }
        break;

      case "queue_joined":
        console.log("Joined queue");
        this.inQueue = true;
        if (message.queueStatus) {
          this.queueStatus = message.queueStatus;
        }
        break;

      case "queue_status":
        console.log("Queue status update:", message.status);
        this.queueStatus = message.status;
        break;

      case "match_found":
        console.log("Match found!", message);
        this.handleMatchFound(message.gameId, message.assignment);
        break;

      case "error":
        console.error("Matchmaking error:", message.error);
        this.error = message.error;
        this.inQueue = false;
        break;

      default:
        console.log("Unknown message type:", message.type);
    }
  }

  private handleMatchFound(gameId: string, assignment: any) {
    console.log(`Match found! Joining game ${gameId}`);

    // Set URL hash to trigger automatic join
    history.pushState(null, "", `#join=${gameId}`);

    // Dispatch event to join the game
    this.dispatchEvent(
      new CustomEvent("join-lobby", {
        detail: {
          gameID: gameId,
          clientID: this.clientID,
        } as JoinLobbyEvent,
        bubbles: true,
        composed: true,
      }),
    );

    // Clean up
    this.inQueue = false;
    this.queueStatus = null;
    this.cleanup();
  }

  private async joinQueue() {
    if (this.inQueue) {
      return;
    }

    // Connect WebSocket if not connected
    await this.connectWebSocket();

    // Function to send join queue message
    const sendJoinMessage = () => {
      if (this.ws && this.ws.readyState === WebSocket.OPEN) {
        this.ws.send(
          JSON.stringify({
            type: "join_queue",
            queueType: this.queueType,
            gameMode: this.gameMode,
          }),
        );
      }
    };

    // Send join queue message immediately if connected, or wait for connection
    if (this.ws) {
      if (this.ws.readyState === WebSocket.OPEN) {
        sendJoinMessage();
      } else if (this.ws.readyState === WebSocket.CONNECTING) {
        // Wait for connection to open before sending join message
        this.ws.addEventListener("open", () => sendJoinMessage(), {
          once: true,
        });
      }
    }
  }

  private leaveQueue() {
    if (!this.inQueue) {
      return;
    }

    // Send leave queue message
    if (this.ws && this.ws.readyState === WebSocket.OPEN) {
      this.ws.send(
        JSON.stringify({
          type: "leave_queue",
        }),
      );
    }

    this.inQueue = false;
    this.queueStatus = null;
    this.cleanup();
  }

  private setQueueType(type: QueueType) {
    if (this.inQueue) {
      return; // Can't change while in queue
    }
    this.queueType = type;
  }

  private setGameMode(mode: GameMode) {
    if (this.inQueue) {
      return; // Can't change while in queue
    }
    this.gameMode = mode;
  }

  render() {
    return html`
      <div class="flex flex-col gap-3">
        <!-- Join Queue Button -->
        <button
          @click=${this.inQueue
            ? () => this.leaveQueue()
            : () => this.joinQueue()}
          ?disabled=${this.isConnecting}
          class="w-full h-16 rounded-xl font-medium text-lg transition-opacity duration-200 ${this
            .inQueue
            ? "bg-gradient-to-r from-red-600 to-red-500 hover:opacity-90"
            : "bg-gradient-to-r from-purple-600 to-purple-500 hover:opacity-90"} text-white ${this
            .isConnecting
            ? "opacity-50 cursor-not-allowed"
            : ""}"
        >
          <div class="flex flex-col items-center justify-center">
            <div>
              ${this.isConnecting
                ? translateText("ranked_queue.connecting")
                : this.inQueue
                  ? translateText("ranked_queue.leave_queue")
                  : translateText("ranked_queue.join_ranked_queue")}
            </div>
            ${!this.inQueue && this.playerElo !== null
              ? html`<div class="text-sm mt-1 opacity-90">
                  ${translateText("ranked_queue.your_elo")} ${this.playerElo}
                </div>`
              : !this.inQueue && this.isLoadingElo
                ? html`<div class="text-sm mt-1 opacity-90">
                    ${translateText("ranked_queue.loading_elo")}
                  </div>`
                : ""}
            ${this.error
              ? html`<div class="text-sm mt-1 text-red-200">${this.error}</div>`
              : ""}
          </div>
        </button>

        <!-- Leaderboard Toggle Button -->
        <button
          @click=${() => (this.showLeaderboard = !this.showLeaderboard)}
          class="w-full py-2 rounded-lg bg-gray-700 hover:bg-gray-600 text-white text-sm font-medium transition-colors"
        >
          ${this.showLeaderboard
            ? translateText("ranked_queue.hide_leaderboard")
            : translateText("ranked_queue.view_leaderboard")}
        </button>

        <!-- Leaderboard Display -->
        ${this.showLeaderboard
          ? html`
              <div
                class="bg-gray-800 rounded-xl p-4 text-white max-h-96 overflow-y-auto"
              >
                ${this.isLoadingLeaderboard
                  ? html`<div class="text-center py-4">
                      ${translateText("ranked_queue.loading_leaderboard")}
                    </div>`
                  : this.leaderboard.length === 0
                    ? html`<div class="text-center py-4 text-gray-400">
                        ${translateText("ranked_queue.no_ranked_players")}
                      </div>`
                    : html`
                        <div class="space-y-2">
                          ${this.leaderboard.slice(0, 10).map(
                            (entry) => html`
                              <div
                                class="flex items-center justify-between p-2 bg-gray-700 rounded-lg hover:bg-gray-600 transition-colors"
                              >
                                <div class="flex items-center gap-3">
                                  <div
                                    class="font-bold text-lg ${entry.rank <= 3
                                      ? "text-yellow-400"
                                      : "text-gray-400"}"
                                  >
                                    #${entry.rank}
                                  </div>
                                  <div>
                                    <div class="font-medium">
                                      ${entry.username}
                                    </div>
                                    <div class="text-xs text-gray-400">
                                      ${entry.gamesPlayed}
                                      ${translateText("ranked_queue.games")} •
                                      ${entry.wins}${translateText(
                                        "ranked_queue.wins_short",
                                      )}
                                      ${entry.losses}${translateText(
                                        "ranked_queue.losses_short",
                                      )}
                                    </div>
                                  </div>
                                </div>
                                <div class="text-right">
                                  <div class="font-bold text-purple-400">
                                    ${entry.currentElo}
                                  </div>
                                  <div class="text-xs text-gray-400">
                                    ${translateText("ranked_queue.elo")}
                                  </div>
                                </div>
                              </div>
                            `,
                          )}
                        </div>
                      `}
              </div>
            `
          : ""}
      </div>
    `;
  }
}