import { Component, OnInit, AfterViewChecked, ElementRef, ViewChild } from '@angular/core';
import { HttpClient, HttpHeaders } from '@angular/common/http';
import { CouchdbService } from '../couchdb.service'; // Import the service
import emailjs, { EmailJSResponseStatus } from 'emailjs-com';

interface Answer {
  text: string;
  next: string;
}

interface Node {
  type: string;
  text: string;
  answers?: Answer[];
  next?: string;
}

interface DecisionTree {
  startNode: string;
  nodes: { [key: string]: Node };
}

@Component({
  selector: 'app-chatbot',
  templateUrl: './chatbot.component.html',
  styleUrls: ['./chatbot.component.css']
})
export class ChatbotComponent implements OnInit, AfterViewChecked {
  decisionTree: DecisionTree = { startNode: '', nodes: {} };
  currentNode: Node = { type: '', text: '' };
  conversation: { speaker: string; text: string }[] = [];
  userInput = '';
  errorMessage = '';
  isMinimized = true;
  leaveDetails: any = {};
  leaveBalance = 0;

  @ViewChild('chatContent') private chatContent!: ElementRef;

  constructor(private couchdbService: CouchdbService, private http: HttpClient) {} // Inject the service

  ngOnInit(): void {
    this.couchdbService.getDecisionTree().subscribe(data => {
      this.decisionTree = data.data;
      this.currentNode = this.decisionTree.nodes[this.decisionTree.startNode];
      this.addMessage('bot', this.currentNode.text);
    });
  }

  ngAfterViewChecked() {
    this.scrollToBottom();
  }

  addMessage(speaker: string, text: string): void {
    this.conversation.push({ speaker, text });
    this.scrollToBottom();
  }

  selectAnswer(answer: Answer): void {
    this.addMessage('user', answer.text);

    // Check for redirection conditions
    if (this.currentNode.text === "Welcome to our Ticket service!") {
      if (answer.text === 'Raise Ticket' || answer.text === 'Ticket Status') {
        window.open('https://e.chain.portal.url', '_blank');
      }
    } else if (this.currentNode.text === "Welcome to our Technical service!") {
      if (answer.text === 'Raise Support') {
        window.open('https://appTrack.portal.url', '_blank');
      }
    }

    if (this.currentNode.text === "Are you sure you want to submit the form?") {
      if (answer.text === 'Yes, submit') {
        this.sendLeaveApplicationEmail();
        this.userInput = ''; // Clear user input
        return;
      } else {
        // Handle other options if needed
      }
    }

    // Move to the next node based on the selected answer
    this.currentNode = this.decisionTree.nodes[answer.next];
    this.processNode();
  }

  submitInput(): void {
    if (!this.userInput.trim()) {
      this.displayErrorMessage('Please enter a value');
      return;
    }

    // Validate email ID
    if (this.currentNode.text === "Enter your Email ID" || this.currentNode.text === "Enter manager Email ID") {
      if (!this.validateEmail(this.userInput)) {
        this.displayErrorMessage('Please enter a valid email ID');
        return;
      }
    }

    // Validate dates
    if (this.currentNode.text === "Please provide the start date for your leave. (Format: YYYY-MM-DD)" || this.currentNode.text === "Please provide the end date for your leave. (Format: YYYY-MM-DD)") {
      if (!this.validateDate(this.userInput)) {
        this.displayErrorMessage('Please enter a valid date in the format YYYY-MM-DD');
        return;
      }

      if (new Date(this.userInput) <= new Date()) {
        this.displayErrorMessage('Please enter a date greater than today\'s date');
        return;
      }
    }

    this.addMessage('user', this.userInput);
    this.errorMessage = '';
    this.leaveDetails[this.currentNode.text] = this.userInput; // Store user input in leaveDetails

    if (this.currentNode.text === "Please provide your employee ID") {
      this.checkEmployeeEligibility(this.userInput);
    } else {
      this.currentNode = this.decisionTree.nodes[this.currentNode.next || ''];
      this.processNode();
    }

    this.userInput = '';
  }

  validateEmail(email: string): boolean {
    const emailPattern = /^[a-zA-Z]+\.[a-zA-Z]+@chainsys\.com$/;
    return emailPattern.test(email);
  }

  validateDate(date: string): boolean {
    const datePattern = /^\d{4}-\d{2}-\d{2}$/;
    return datePattern.test(date);
  }

  checkEmployeeEligibility(employeeId: string): void {
    const url = `https://192.168.57.185:5984/employee-db/${employeeId}`;
    const headers = new HttpHeaders({
      'Authorization': 'Basic ' + btoa('d_couchdb:Welcome#2')
    });

    this.http.get<any>(url, { headers }).subscribe(
      data => {
        data.leaveBalance = data.leaveBalance || 0; // Ensure leaveBalance is initialized if null

        this.leaveBalance = data.leaveBalance;
        this.leaveDetails['leaveBalance'] = this.leaveBalance;

        if (this.leaveBalance > 0) {
          this.currentNode = this.decisionTree.nodes['nodeEligibilityResult'];
        } else {
          this.addMessage('bot', 'You are not eligible to apply for leave.');
          this.currentNode = this.decisionTree.nodes[this.decisionTree.startNode];
        }
        this.processNode();
      },
      error => {
        this.addMessage('bot', 'No record found.');
        this.currentNode = this.decisionTree.nodes[this.decisionTree.startNode];
        this.processNode();
      }
    );
  }

  processNode(): void {
    if (!this.currentNode) {
      console.error('Invalid node configuration');
      return;
    }

    if (this.currentNode.type === 'question' && this.currentNode.text === 'No. of days') {
      // Adjust leave options based on leave balance
      const maxDays = Math.min(this.leaveBalance, 5); // Maximum of 5 days or leave balance, whichever is smaller
      this.currentNode.answers = this.currentNode.answers?.filter(answer => parseInt(answer.text, 10) <= maxDays);
    }

    const botMessage = this.replaceVariables(this.currentNode.text);
    this.addMessage('bot', botMessage);
  }

  replaceVariables(text: string): string {
    return text.replace(/\[\w+\]/g, match => this.leaveDetails[match.slice(1, -1)] || match);
  }

  toggleMinimize(event?: Event): void {
    if (event) {
      event.stopPropagation();
    }
    this.isMinimized = !this.isMinimized;
  }

  closeChat(event?: Event): void {
    const confirmClose = confirm("Are you sure you want to close the chat?");
    if (event) {
      event.stopPropagation();
    }
    this.isMinimized = !this.isMinimized;
  }

  private scrollToBottom(): void {
    try {
      this.chatContent.nativeElement.scrollTop = this.chatContent.nativeElement.scrollHeight;
    } catch (err) {
      console.error('Scroll to bottom failed:', err);
    }
  }

  displayErrorMessage(message: string): void {
    this.errorMessage = message;
    setTimeout(() => {
      this.errorMessage = '';
    }, 2000);
  }

  sendLeaveApplicationEmail(): void {
    const templateParams = {
      employee_email: this.leaveDetails['Enter your Email ID'],
      manager_email: this.leaveDetails['Enter manager Email ID'],
      employee_id: this.leaveDetails['Please provide your employee ID'],
      leave_type: this.leaveDetails['Type of leave'],
      leave_reason: this.leaveDetails['Reason for the leave'],
      leave_days: this.leaveDetails['No. of days'],
      start_date: this.leaveDetails['Please provide the start date for your leave. (Format: YYYY-MM-DD)'],
      end_date: this.leaveDetails['Please provide the end date for your leave. (Format: YYYY-MM-DD)']
    };

    emailjs.send('service_g7y50fu', 'template_20nsgam', templateParams, '8pjnXdcFSoOVX9B6c')
      .then((response: EmailJSResponseStatus) => {
        console.log('SUCCESS!', response.status, response.text);
        this.currentNode = this.decisionTree.nodes['node13'];
        this.processNode();
      }, (error) => {
        console.error('FAILED...', error);
      });
  }
}