import { CommonModule } from '@angular/common';
import { Component, OnDestroy, OnInit, Optional } from '@angular/core';
import { ActivatedRoute } from '@angular/router';
import { FormsModule } from '@angular/forms';

import { createApiClient } from '../../../../../src/api/client';
import { createSessionContextStore } from '../../../../../src/spa/session-context-store';
import { createVerticalSliceController } from '../../../../../src/spa/vertical-slice';
import type { RouteSessionContext } from '../../session-route-context';

interface SessionDetail {
  session: { code: string; status: string; current_round: number };
  round_question: { id: number; prompt: string; answers: Array<{ text: string }> } | null;
  players: Array<{ id: number; nickname: string; score: number }>;
}

type ConnectionState = 'online' | 'reconnecting' | 'offline';
type LoadingTransition = 'refresh' | 'join' | 'submit-lie' | 'submit-guess' | null;

function resolveLocalStorage(): Storage | undefined {
  if (typeof window === 'undefined') {
    return undefined;
  }
  return window.localStorage;
}

@Component({
  selector: 'app-player-shell',
  standalone: true,
  imports: [CommonModule, FormsModule],
  template: `
    <h2>Player SPA gameplay flow</h2>

    <div class="panel">
      <label>Session code <input [(ngModel)]="sessionCode" /></label>
      <label>Nickname <input [(ngModel)]="nickname" /></label>
      <button (click)="refreshSession()" [disabled]="loading">Refresh</button>
      <button (click)="joinSession()" [disabled]="loading">Join</button>
    </div>

    <p *ngIf="connectionState === 'reconnecting'" class="error">
      Reconnecting… trying to refresh session state.
      <button type="button" (click)="retryReconnect()" [disabled]="loading">Retry now</button>
      <button type="button" (click)="returnToJoin()" [disabled]="loading">Back to join</button>
    </p>
    <p *ngIf="connectionState === 'offline'" class="error">
      You are offline. Reconnect to continue gameplay.
      <button type="button" (click)="retryReconnect()" [disabled]="loading">Retry now</button>
      <button type="button" (click)="returnToJoin()" [disabled]="loading">Back to join</button>
    </p>

    <p *ngIf="loading" class="hint">{{ loadingMessage }}</p>

    <div class="panel" *ngIf="session">
      <p><strong>Status:</strong> {{ session.session.status }}</p>
      <p *ngIf="session.round_question"><strong>Prompt:</strong> {{ session.round_question.prompt }}</p>

      <label>Løgn <input [(ngModel)]="lieText" [disabled]="loading || session.session.status !== 'lie'" /></label>
      <button (click)="submitLie()" [disabled]="loading || session.session.status !== 'lie'">Submit lie</button>
      <button *ngIf="submitError?.kind === 'lie'" (click)="submitLie()" [disabled]="loading">Retry lie submit</button>

      <div class="answers" *ngIf="session.round_question?.answers?.length">
        <button
          type="button"
          *ngFor="let answer of session.round_question?.answers"
          (click)="selectedGuess = answer.text"
          [class.active]="selectedGuess === answer.text"
          [disabled]="loading || session.session.status !== 'guess'"
        >
          {{ answer.text }}
        </button>
      </div>

      <button (click)="submitGuess()" [disabled]="loading || session.session.status !== 'guess' || !selectedGuess">Submit guess</button>
      <button *ngIf="submitError?.kind === 'guess'" (click)="submitGuess()" [disabled]="loading">Retry guess submit</button>

      <div *ngIf="session.session.status === 'finished' && finalLeaderboard.length">
        <h3>Final leaderboard</h3>
        <ol>
          <li *ngFor="let entry of finalLeaderboard">{{ entry.nickname }}: {{ entry.score }}</li>
        </ol>
      </div>
    </div>

    <p *ngIf="error" class="error">{{ error }}</p>
    <p *ngIf="submitError" class="error">{{ submitError.message }}</p>

    <div class="panel" *ngIf="error || submitError">
      <button type="button" (click)="retryReconnect()" [disabled]="loading">Retry</button>
      <button type="button" (click)="returnToJoin()" [disabled]="loading">Back to join</button>
    </div>
  `,
})
export class PlayerShellComponent implements OnInit, OnDestroy {
  sessionCode = '';
  nickname = '';
  playerId = 0;
  sessionToken = '';
  lieText = '';
  selectedGuess = '';
  loading = false;
  error = '';
  submitError: { kind: 'lie' | 'guess'; message: string } | null = null;
  session: SessionDetail | null = null;
  finalLeaderboard: Array<{ id: number; nickname: string; score: number }> = [];
  connectionState: ConnectionState = 'online';
  loadingTransition: LoadingTransition = null;

  private readonly sessionContextStore = createSessionContextStore(resolveLocalStorage());
  private readonly controller = createVerticalSliceController(createApiClient(), this.sessionContextStore);
  private reconnectTimer: ReturnType<typeof setTimeout> | null = null;

  constructor(@Optional() private readonly route: ActivatedRoute | null = null) {
    if (typeof navigator !== 'undefined' && !navigator.onLine) {
      this.connectionState = 'offline';
    }

    if (typeof window !== 'undefined') {
      window.addEventListener('online', this.handleOnline);
      window.addEventListener('offline', this.handleOffline);
    }
  }

  ngOnInit(): void {
    const routeContext = this.route?.snapshot.data['routeContext'] as RouteSessionContext | undefined;
    const persistedContext = this.sessionContextStore.get();

    this.playerId = routeContext?.playerId ?? persistedContext?.playerId ?? 0;
    this.sessionToken = routeContext?.token ?? persistedContext?.token ?? '';

    const candidate = routeContext?.sessionCode || persistedContext?.sessionCode || '';
    if (!candidate) {
      return;
    }

    this.sessionCode = this.normalizeCode(candidate);
    void this.refreshSession();
  }

  ngOnDestroy(): void {
    if (typeof window !== 'undefined') {
      window.removeEventListener('online', this.handleOnline);
      window.removeEventListener('offline', this.handleOffline);
    }
    this.clearReconnectTimer();
  }

  private readonly handleOnline = (): void => {
    this.connectionState = 'reconnecting';
    void this.retryReconnect();
  };

  private readonly handleOffline = (): void => {
    this.connectionState = 'offline';
    this.clearReconnectTimer();
  };

  private clearReconnectTimer(): void {
    if (this.reconnectTimer) {
      clearTimeout(this.reconnectTimer);
      this.reconnectTimer = null;
    }
  }

  get loadingMessage(): string {
    switch (this.loadingTransition) {
      case 'join':
        return 'Joining session… restoring your player state.';
      case 'submit-lie':
        return 'Submitting lie… waiting for guess phase.';
      case 'submit-guess':
        return 'Submitting guess… waiting for reveal.';
      case 'refresh':
      default:
        return 'Loading latest session state…';
    }
  }

  private normalizeCode(value: string): string {
    return value.trim().toUpperCase();
  }

  private toMessage(error: unknown): string {
    if (error instanceof Error && error.message) {
      return error.message;
    }
    return 'Unknown error';
  }

  private markOnline(): void {
    this.connectionState = 'online';
    this.clearReconnectTimer();
  }

  private markConnectionIssue(error: unknown): void {
    if (typeof navigator !== 'undefined' && !navigator.onLine) {
      this.connectionState = 'offline';
      return;
    }

    const message = this.toMessage(error).toLowerCase();
    if (
      message.includes('fetch') ||
      message.includes('network') ||
      message.includes('failed to') ||
      message.includes('could not load lobby status') ||
      message.includes('session refresh failed')
    ) {
      this.connectionState = 'reconnecting';
      this.scheduleReconnect();
    }
  }

  private scheduleReconnect(): void {
    if (this.reconnectTimer || !this.sessionCode.trim()) {
      return;
    }

    this.reconnectTimer = setTimeout(() => {
      this.reconnectTimer = null;
      void this.retryReconnect();
    }, 2000);
  }

  async retryReconnect(): Promise<void> {
    if (!this.sessionCode.trim() || this.loading) {
      return;
    }

    await this.refreshSession();
  }

  returnToJoin(): void {
    this.loadingTransition = null;
    this.clearReconnectTimer();
    this.connectionState = typeof navigator !== 'undefined' && !navigator.onLine ? 'offline' : 'online';
    this.session = null;
    this.finalLeaderboard = [];
    this.selectedGuess = '';
    this.lieText = '';
    this.submitError = null;
    this.error = '';
    this.playerId = 0;
    this.sessionToken = '';
    this.sessionContextStore.clear();
  }

  private syncFinalLeaderboard(): void {
    if (!this.session || this.session.session.status !== 'finished') {
      this.finalLeaderboard = [];
      return;
    }

    this.finalLeaderboard = [...this.session.players].sort((a, b) => {
      if (b.score !== a.score) {
        return b.score - a.score;
      }
      return a.nickname.localeCompare(b.nickname);
    });
  }

  private async request<T>(path: string, method: 'GET' | 'POST', payload?: unknown): Promise<T> {
    const response = await fetch(path, {
      method,
      headers: {
        Accept: 'application/json',
        ...(payload === undefined ? {} : { 'Content-Type': 'application/json' }),
      },
      ...(payload === undefined ? {} : { body: JSON.stringify(payload) }),
      credentials: 'same-origin',
    });

    const body = await response.json().catch(() => ({}));
    if (!response.ok) {
      throw new Error((body as { error?: string }).error ?? `HTTP ${response.status}`);
    }

    return body as T;
  }

  async refreshSession(): Promise<void> {
    this.loading = true;
    this.loadingTransition = 'refresh';
    this.error = '';
    try {
      const state = await this.controller.hydrateLobby(this.sessionCode);
      if (!state.session || state.errorMessage) {
        throw new Error(state.errorMessage ?? 'Unknown error');
      }
      this.session = state.session as SessionDetail;
      this.sessionCode = this.session.session.code;
      if (this.session.session.status !== 'guess') {
        this.selectedGuess = '';
      }
      this.syncFinalLeaderboard();
      this.markOnline();
    } catch (error) {
      this.error = `Session refresh failed: ${this.toMessage(error)}`;
      this.markConnectionIssue(error);
    } finally {
      this.loading = false;
      this.loadingTransition = null;
    }
  }

  async joinSession(): Promise<void> {
    this.loading = true;
    this.loadingTransition = 'join';
    this.error = '';
    try {
      const state = await this.controller.joinLobby(this.sessionCode, this.nickname);
      if (!state.session || state.errorMessage) {
        throw new Error(state.errorMessage ?? 'Unknown error');
      }
      this.session = state.session as SessionDetail;
      this.sessionCode = this.session.session.code;

      const sessionContext = this.sessionContextStore.get();
      this.playerId = sessionContext?.playerId ?? 0;
      this.sessionToken = sessionContext?.token ?? '';
      if (this.session.session.status !== 'guess') {
        this.selectedGuess = '';
      }
      this.syncFinalLeaderboard();
      this.markOnline();
    } catch (error) {
      this.error = `Join failed: ${this.toMessage(error)}`;
      this.markConnectionIssue(error);
    } finally {
      this.loading = false;
      this.loadingTransition = null;
    }
  }

  async submitLie(): Promise<void> {
    if (!this.session?.round_question?.id) {
      return;
    }
    this.loading = true;
    this.loadingTransition = 'submit-lie';
    this.submitError = null;
    try {
      await this.request(
        `/lobby/sessions/${encodeURIComponent(this.normalizeCode(this.sessionCode))}/questions/${this.session.round_question.id}/lies/submit`,
        'POST',
        {
          player_id: this.playerId,
          session_token: this.sessionToken,
          text: this.lieText,
        }
      );
      await this.refreshSession();
      this.markOnline();
    } catch (error) {
      this.submitError = { kind: 'lie', message: `Lie submit failed: ${this.toMessage(error)}` };
      this.markConnectionIssue(error);
    } finally {
      this.loading = false;
      this.loadingTransition = null;
    }
  }

  async submitGuess(): Promise<void> {
    if (!this.session?.round_question?.id || !this.selectedGuess) {
      return;
    }
    this.loading = true;
    this.loadingTransition = 'submit-guess';
    this.submitError = null;
    try {
      await this.request(
        `/lobby/sessions/${encodeURIComponent(this.normalizeCode(this.sessionCode))}/questions/${this.session.round_question.id}/guesses/submit`,
        'POST',
        {
          player_id: this.playerId,
          session_token: this.sessionToken,
          selected_text: this.selectedGuess,
        }
      );
      await this.refreshSession();
      this.markOnline();
    } catch (error) {
      this.submitError = { kind: 'guess', message: `Guess submit failed: ${this.toMessage(error)}` };
      this.markConnectionIssue(error);
    } finally {
      this.loading = false;
      this.loadingTransition = null;
    }
  }
}