import { CommonModule, CurrencyPipe, DatePipe } from '@angular/common';
import { Component, OnInit, inject, signal } from '@angular/core';
import { FormArray, FormBuilder, ReactiveFormsModule, Validators } from '@angular/forms';
import { CategoriesService } from '../../core/services/categories.service';
import { RecurringExpensesService } from '../../core/services/recurring-expenses.service';
import { ToastService } from '../../core/services/toast.service';
import { UiService } from '../../core/services/ui.service';
import type { RecurringExpense } from '../../shared/models';

const today = () => new Date().toISOString().slice(0, 10);

@Component({
  selector: 'app-recurring',
  standalone: true,
  imports: [CommonModule, ReactiveFormsModule, CurrencyPipe, DatePipe],
  templateUrl: './recurring.component.html'
})
export class RecurringComponent implements OnInit {
  readonly ui = inject(UiService);
  private readonly fb = inject(FormBuilder);
  private readonly categoriesService = inject(CategoriesService);
  private readonly recurringService = inject(RecurringExpensesService);
  private readonly toast = inject(ToastService);

  readonly categories = this.categoriesService.items;
  readonly items = signal<RecurringExpense[]>([]);
  readonly editingId = signal<string | null>(null);

  readonly form = this.fb.nonNullable.group({
    title: ['', [Validators.required, Validators.minLength(2)]],
    amount: [0, [Validators.required, Validators.min(0.01)]],
    categoryId: ['', Validators.required],
    defaultStatus: ['PENDING' as RecurringExpense['defaultStatus']],
    frequency: ['MONTHLY' as RecurringExpense['frequency']],
    intervalValue: [1, [Validators.required, Validators.min(1)]],
    startDate: [today(), Validators.required],
    nextRunDate: [today(), Validators.required],
    endDate: [''],
    maxOccurrences: [null as number | null],
    merchant: [''],
    description: [''],
    tagsText: [''],
    isActive: [true],
    customFields: this.fb.array([])
  });

  get customFields() { return this.form.controls.customFields as FormArray; }

  ngOnInit() {
    this.categoriesService.ensureLoaded(true);
    this.load();
  }

  load() {
    this.recurringService.list().subscribe({ next: (response) => this.items.set(response.items) });
  }

  addCustomField(key = '', value = '') { this.customFields.push(this.fb.group({ key: [key], value: [value] })); }
  removeCustomField(index: number) { this.customFields.removeAt(index); }

  save() {
    if (this.form.invalid) return;
    const raw = this.form.getRawValue();
    const customEntries = this.customFields.getRawValue().map((item: { key: string; value: string }) => [item.key, item.value] as [string, string]).filter(([key, value]) => Boolean(key && value));
    const payload = {
      ...raw,
      categoryId: raw.categoryId,
      endDate: raw.endDate || null,
      maxOccurrences: raw.maxOccurrences ? Number(raw.maxOccurrences) : null,
      tags: raw.tagsText.split(',').map((item) => item.trim()).filter(Boolean),
      customFields: Object.fromEntries(customEntries)
    };
    const request = this.editingId() ? this.recurringService.update(this.editingId()!, payload) : this.recurringService.create(payload);
    request.subscribe({ next: () => { this.toast.success(this.ui.t('recurring.saved')); this.cancelEdit(); this.load(); }, error: (error) => this.toast.error(error.error?.message ?? this.ui.t('recurring.saveError')) });
  }

  edit(item: RecurringExpense) {
    this.editingId.set(item.id);
    this.customFields.clear();
    Object.entries(item.customFields || {}).forEach(([key, value]) => this.addCustomField(key, value));
    this.form.reset({ title: item.title, amount: item.amount, categoryId: item.category.id, defaultStatus: item.defaultStatus, frequency: item.frequency, intervalValue: item.intervalValue, startDate: item.startDate, nextRunDate: item.nextRunDate, endDate: item.endDate || '', maxOccurrences: item.maxOccurrences, merchant: item.merchant || '', description: item.description || '', tagsText: item.tags.join(', '), isActive: item.isActive, customFields: [] as never[] });
  }

  cancelEdit() {
    this.editingId.set(null);
    this.customFields.clear();
    this.form.reset({ title: '', amount: 0, categoryId: '', defaultStatus: 'PENDING', frequency: 'MONTHLY', intervalValue: 1, startDate: today(), nextRunDate: today(), endDate: '', maxOccurrences: null, merchant: '', description: '', tagsText: '', isActive: true, customFields: [] as never[] });
  }

  remove(item: RecurringExpense) {
    this.recurringService.delete(item.id).subscribe({ next: () => { this.toast.success(this.ui.t('recurring.deleted')); this.load(); }, error: (error) => this.toast.error(error.error?.message ?? this.ui.t('recurring.deleteError')) });
  }

  runNow() {
    this.recurringService.runNow().subscribe({ next: () => { this.toast.success(this.ui.t('recurring.ran')); this.load(); }, error: (error) => this.toast.error(error.error?.message ?? this.ui.t('toast.error')) });
  }
}