import {Component, OnInit, inject} from '@angular/core';
import { CommonModule } from '@angular/common';
import { FormsModule } from '@angular/forms';
import { MatCardModule } from '@angular/material/card';
import { MatButtonModule } from '@angular/material/button';
import { MatInputModule } from '@angular/material/input';
import { MatFormFieldModule } from '@angular/material/form-field';
import { MatSelectModule } from '@angular/material/select';
import { MatIconModule } from '@angular/material/icon';
import { MatTableModule } from '@angular/material/table';
import { MatSnackBar, MatSnackBarModule } from '@angular/material/snack-bar';
import { MatProgressSpinnerModule } from '@angular/material/progress-spinner';
import { DashboardService, AdminStats } from '../../services/dashboard';
import { HttpClient } from '@angular/common/http';
import { environment } from '../../../environments/environment';
import { AuthService } from '../../services/auth';

interface CommunityMember {
  userId: string;
  firstName: string;
  lastName: string;
  email: string;
}

interface TariffInvite {
  id: string;
  producerUserId: string;
  consumerUserId: string;
  energyCommunityId: string;
  code: string;
  note: string;
  status: string;
  expiresAt: string;
  acceptedAt: string;
  createdAt: string;
}

interface EnergyCommunity {
  id: string;
  name: string;
}

@Component({
  selector: 'app-producer-invites',
  standalone: true,
  imports: [
    CommonModule,
    FormsModule,
    MatCardModule,
    MatButtonModule,
    MatInputModule,
    MatFormFieldModule,
    MatSelectModule,
    MatIconModule,
    MatTableModule,
    MatSnackBarModule,
    MatProgressSpinnerModule
  ],
  template: `
    <div class="space-y-6">
      <h1 class="text-2xl font-bold text-slate-800">Meine Einladungen</h1>

      <!-- Neue Einladung erstellen -->
      <mat-card>
        <mat-card-header>
          <mat-card-title>Neue Einladung erstellen</mat-card-title>
          <mat-card-subtitle>Laden Sie einen Consumer ein, einen Spezial-Tarif zu erhalten</mat-card-subtitle>
        </mat-card-header>
        <mat-card-content class="mt-4">
          @if (communities.length === 0) {
            <p class="text-slate-500">Sie sind noch keiner Energiegemeinschaft beigetreten.</p>
          } @else {
            <div class="space-y-4">
              <mat-form-field appearance="outline" class="w-full">
                <mat-label>Energiegemeinschaft</mat-label>
                <mat-select [(ngModel)]="selectedCommunityId" (selectionChange)="loadMembers()">
                  @for (community of communities; track community.id) {
                    <mat-option [value]="community.id">{{ community.name }}</mat-option>
                  }
                </mat-select>
              </mat-form-field>

              @if (selectedCommunityId) {
                <mat-form-field appearance="outline" class="w-full">
                  <mat-label>Consumer auswählen</mat-label>
                  <mat-select [(ngModel)]="selectedConsumerId">
                    @for (member of members; track member.userId) {
                      <mat-option [value]="member.userId">{{ member.firstName }} {{ member.lastName }}</mat-option>
                    }
                  </mat-select>
                </mat-form-field>

                <mat-form-field appearance="outline" class="w-full">
                  <mat-label>Notiz (optional)</mat-label>
                  <textarea matInput [(ngModel)]="inviteNote" rows="3"
                    placeholder="z.B. Ich biete Ihnen einen Spezial-Tarif von 15 Cent/kWh an..."></textarea>
                </mat-form-field>

                <button mat-raised-button color="primary" (click)="createInvite()"
                  [disabled]="!selectedConsumerId || isLoading">
                  @if (isLoading) {
                    <mat-spinner diameter="20"></mat-spinner>
                  } @else {
                    <ng-container>
                      <mat-icon>send</mat-icon>
                      Einladung senden
                    </ng-container>
                  }
                </button>
              }
            </div>
          }
        </mat-card-content>
      </mat-card>

      <!-- Gesendete Einladungen -->
      <mat-card>
        <mat-card-header>
          <mat-card-title>Gesendete Einladungen</mat-card-title>
        </mat-card-header>
        <mat-card-content class="mt-4">
          @if (invites.length === 0) {
            <p class="text-slate-500">Noch keine Einladungen gesendet.</p>
          } @else {
            <table mat-table [dataSource]="invites" class="w-full">
              <ng-container matColumnDef="consumer">
                <th mat-header-cell *matHeaderCellDef>Consumer</th>
                <td mat-cell *matCellDef="let invite">{{ invite.consumerUserId }}</td>
              </ng-container>

              <ng-container matColumnDef="code">
                <th mat-header-cell *matHeaderCellDef>Code</th>
                <td mat-cell *matCellDef="let invite">
                  <code class="bg-slate-100 px-2 py-1 rounded">{{ invite.code }}</code>
                </td>
              </ng-container>

              <ng-container matColumnDef="status">
                <th mat-header-cell *matHeaderCellDef>Status</th>
                <td mat-cell *matCellDef="let invite">
                  <span [class]="getStatusClass(invite.status)">{{ getStatusLabel(invite.status) }}</span>
                </td>
              </ng-container>

              <ng-container matColumnDef="expiresAt">
                <th mat-header-cell *matHeaderCellDef>Gültig bis</th>
                <td mat-cell *matCellDef="let invite">{{ invite.expiresAt | date:'dd.MM.yyyy HH:mm' }}</td>
              </ng-container>

              <tr mat-header-row *matHeaderRowDef="displayedColumns"></tr>
              <tr mat-row *matRowDef="let row; columns: displayedColumns;"></tr>
            </table>
          }
        </mat-card-content>
      </mat-card>
    </div>
  `
})
export class ProducerInvitesComponent implements OnInit {
  private http = inject(HttpClient);
  private snackBar = inject(MatSnackBar);
  private authService = inject(AuthService);

  private apiUrl = `${environment.apiUrl}/api`;

  communities: EnergyCommunity[] = [];
  members: CommunityMember[] = [];
  invites: TariffInvite[] = [];

  selectedCommunityId: string = '';
  selectedConsumerId: string = '';
  inviteNote: string = '';

  isLoading = false;

  displayedColumns = ['consumer', 'code', 'status', 'expiresAt'];

  ngOnInit() {
    this.loadCommunities();
  }

  loadCommunities() {
    this.http.get<EnergyCommunity[]>(`${this.apiUrl}/community/admin/communities`)
      .subscribe({
        next: (communities) => this.communities = communities,
        error: () => this.snackBar.open('Fehler beim Laden der Energiegemeinschaften', 'Schließen', { duration: 3000 })
      });
  }

  loadMembers() {
    if (!this.selectedCommunityId) return;

    this.http.get<CommunityMember[]>(`${this.apiUrl}/community/admin/communities/${this.selectedCommunityId}/members`)
      .subscribe({
        next: (members) => {
          const currentUserId = this.authService.getCurrentUserId();
          this.members = members.filter(m => m.userId !== currentUserId);
        },
        error: () => this.snackBar.open('Fehler beim Laden der Mitglieder', 'Schließen', { duration: 3000 })
      });

    this.loadInvites();
  }

  loadInvites() {
    if (!this.selectedCommunityId) return;

    this.http.get<TariffInvite[]>(`${this.apiUrl}/tariffs/invites/community/${this.selectedCommunityId}`)
      .subscribe({
        next: (invites) => this.invites = invites,
        error: () => this.snackBar.open('Fehler beim Laden der Einladungen', 'Schließen', { duration: 3000 })
      });
  }

  createInvite() {
    if (!this.selectedConsumerId || !this.selectedCommunityId) return;

    this.isLoading = true;

    const request = {
      consumerUserId: this.selectedConsumerId,
      energyCommunityId: this.selectedCommunityId,
      note: this.inviteNote || null
    };

    this.http.post<TariffInviteRequest>(`${this.apiUrl}/tariffs/invites`, request)
      .subscribe({
        next: (invite) => {
          this.isLoading = false;
          this.snackBar.open('Einladung erfolgreich gesendet!', 'Schließen', { duration: 3000 });
          this.inviteNote = '';
          this.selectedConsumerId = '';
          this.loadInvites();
        },
        error: (err) => {
          this.isLoading = false;
          const message = err.error?.message || 'Fehler beim Erstellen der Einladung';
          this.snackBar.open(message, 'Schließen', { duration: 5000 });
        }
      });
  }

  getStatusClass(status: string): string {
    switch (status) {
      case 'PENDING': return 'text-yellow-600 bg-yellow-100 px-2 py-1 rounded';
      case 'ACCEPTED': return 'text-green-600 bg-green-100 px-2 py-1 rounded';
      case 'EXPIRED': return 'text-red-600 bg-red-100 px-2 py-1 rounded';
      default: return 'text-slate-600 bg-slate-100 px-2 py-1 rounded';
    }
  }

  getStatusLabel(status: string): string {
    switch (status) {
      case 'PENDING': return 'Ausstehend';
      case 'ACCEPTED': return 'Angenommen';
      case 'EXPIRED': return 'Abgelaufen';
      default: return status;
    }
  }
}

interface TariffInviteRequest {
  consumerUserId: string;
  energyCommunityId: string;
  note: string | null;
}