import { Component, OnInit } from '@angular/core';
import { CommonModule } from '@angular/common';
import { TranslateModule } from '@ngx-translate/core';
import { ExcelExportService } from '../shared/services/excel-export.service';
import { TRANSACTION_LOGS_FILE_NAME } from '../utils/app.constants';
import { pageSizeOptions } from '../utils/app.constants';
import { NgSelectModule } from '@ng-select/ng-select';
import { FormsModule, ReactiveFormsModule } from '@angular/forms';
import { TableFilterPipe } from '../shared/pipes/table-filter.pipe';
import { TransactionLog } from "../models/user";
import { URIKey } from '../utils/uri-enums';
import { HttpParams } from '@angular/common/http';
import { HttpURIService } from '../app.http.uri.service';
import { formatDate } from '@angular/common';

@Component({
  selector: 'app-transaction-logs',
  templateUrl: './transaction-logs.component.html',
  styleUrls: ['./transaction-logs.component.scss'],
  imports: [CommonModule, TranslateModule, NgSelectModule, FormsModule, ReactiveFormsModule, TableFilterPipe]
})
export class TransactionLogsComponent implements OnInit {
  currentPage: number = 1;
  totalCount: number = 0;
  renewalDataExpanded: boolean = true;
  pageSizeOptions = pageSizeOptions;
  itemsPerPage: number = 10;
  transactionLog: TransactionLog[] = [];
  isLoading = false;
  pagedItems: any[] = [];
  errorMessage: string = '';
  searchText: string = '';
  allItems: TransactionLog[] = [];
  transactionDataExpanded: boolean = true;
  
  // Date range properties
  fromDate: string = '';
  toDate: string = '';
  maxDate: string = '';
  showDateFilters: boolean = false;
  
  constructor(
    private excelExportService: ExcelExportService,
    private httpService: HttpURIService,
  ) {}

  ngOnInit(): void {
    // Set max date to today
    this.maxDate = formatDate(new Date(), 'yyyy-MM-dd', 'en-US');
    
    // Optionally set default date range (last 30 days)
    const today = new Date();
    const lastMonth = new Date();
    lastMonth.setDate(today.getDate() - 30);
    
    this.fromDate = formatDate(lastMonth, 'yyyy-MM-dd', 'en-US');
    this.toDate = formatDate(today, 'yyyy-MM-dd', 'en-US');
    
    this.loadTransactionLogs();   
  }

  loadTransactionLogs(): void {
    this.isLoading = true;
    this.errorMessage = '';
    
    // Build query parameters
    let params = new HttpParams();
    
    // Add pagination parameters
    params = params.set('page', this.currentPage.toString());
    params = params.set('limit', this.itemsPerPage.toString());
    
    // Add date filters if provided
    if (this.fromDate) {
      params = params.set('fromDate', this.fromDate);
    }
    
    if (this.toDate) {
      params = params.set('toDate', this.toDate);
    }
    
    // Add search filter if provided
    if (this.searchText && this.searchText.trim() !== '') {
      params = params.set('search', this.searchText.trim());
    }
    
    this.httpService
      .requestGET<any>(URIKey.TRANSACTION_LOGS, params)
      .subscribe({
        next: (res) => {
          const logs = Array.isArray(res) ? res : res?.data;
          this.transactionLog = logs ?? [];
          this.allItems = [...this.transactionLog];
          
          // Get total count from response
          if (res?.total !== undefined) {
            this.totalCount = res.total;
          } else if (res?.pagination?.total !== undefined) {
            this.totalCount = res.pagination.total;
          } else if (res?.meta?.total !== undefined) {
            this.totalCount = res.meta.total;
          } else {
            this.totalCount = this.transactionLog.length;
          }
          
          this.updatePagedItems();
          this.isLoading = false;
        },
        error: (err) => {
          console.error('Error fetching transaction logs:', err);
          this.errorMessage = err.message || 'Failed to load transaction logs. Please try again.';
          this.transactionLog = [];
          this.allItems = [];
          this.totalCount = 0;
          this.pagedItems = [];
          this.isLoading = false;
        },
        complete: () => {
          this.isLoading = false;
        }
      });
  }

  // Date filter change handler
  onDateFilterChange(): void {
    // Validate date range
    if (this.fromDate && this.toDate) {
      const from = new Date(this.fromDate);
      const to = new Date(this.toDate);
      
      if (from > to) {
        this.errorMessage = 'From date cannot be after To date';
        return;
      }
    }
    
    // Reset to first page and reload
    this.currentPage = 1;
    this.loadTransactionLogs();
  }

  // Clear date filters
  clearDateFilters(): void {
    this.fromDate = '';
    this.toDate = '';
    this.currentPage = 1;
    this.loadTransactionLogs();
  }

  // Toggle date filter visibility
  toggleDateFilters(): void {
    this.showDateFilters = !this.showDateFilters;
  }

  // Apply default date range (Last 7 days)
  applyLast7Days(): void {
    const today = new Date();
    const lastWeek = new Date();
    lastWeek.setDate(today.getDate() - 7);
    
    this.fromDate = formatDate(lastWeek, 'yyyy-MM-dd', 'en-US');
    this.toDate = formatDate(today, 'yyyy-MM-dd', 'en-US');
    this.onDateFilterChange();
  }

  // Apply default date range (Last 30 days)
  applyLast30Days(): void {
    const today = new Date();
    const lastMonth = new Date();
    lastMonth.setDate(today.getDate() - 30);
    
    this.fromDate = formatDate(lastMonth, 'yyyy-MM-dd', 'en-US');
    this.toDate = formatDate(today, 'yyyy-MM-dd', 'en-US');
    this.onDateFilterChange();
  }

  // Apply default date range (This month)
  applyThisMonth(): void {
    const today = new Date();
    const firstDay = new Date(today.getFullYear(), today.getMonth(), 1);
    
    this.fromDate = formatDate(firstDay, 'yyyy-MM-dd', 'en-US');
    this.toDate = formatDate(today, 'yyyy-MM-dd', 'en-US');
    this.onDateFilterChange();
  }

  toggleTableCard(): void {
    this.transactionDataExpanded = !this.transactionDataExpanded;
  }

  itemsPerPageChanged(): void {
    this.currentPage = 1;
    this.loadTransactionLogs();
  }

  onSearch(value: string): void {
    this.searchText = value;
    this.currentPage = 1;
    
    // Debounce search to avoid too many API calls
    clearTimeout((this as any).searchTimeout);
    (this as any).searchTimeout = setTimeout(() => {
      this.loadTransactionLogs();
    }, 300);
  }

  totalPages(): number {
    return Math.ceil(this.totalCount / this.itemsPerPage);
  }

  previousPage(): void {
    if (this.currentPage > 1) {
      this.currentPage--;
      this.loadTransactionLogs();
    }
  }

  updatePagedItems(): void {
    // For client-side display with table filter pipe
    const startIndex = (this.currentPage - 1) * this.itemsPerPage;
    const endIndex = startIndex + this.itemsPerPage;
    
    // If using server-side pagination, use transactionLog directly
    // If using client-side filtering with tableFilter pipe, this might not be needed
    this.pagedItems = this.allItems.slice(startIndex, endIndex);
  }

  nextPage(): void {
    if (this.currentPage < this.totalPages()) {
      this.currentPage++;
      this.loadTransactionLogs();
    }
  }
  
  exportDataInExcel(): void {
    // Export filtered data
    const dataToExport = this.allItems.length > 0 ? this.allItems : this.transactionLog;
    this.excelExportService.exportExcel(dataToExport, TRANSACTION_LOGS_FILE_NAME);
  }

  // Get filtered items for display (used in template)
  get filteredItems(): TransactionLog[] {
    return this.allItems;
  }
}