import { Component, inject, signal } from '@angular/core';
import { ActivatedRoute, RouterLink } from '@angular/router';
import { finalize as rxFinalize } from 'rxjs';
import {
  ConditionReportService,
  FurnitureInventory,
  FurnitureInventoryLine,
  FurniturePresence,
} from '../../services/condition-report.service';
import { httpErrorMessage } from '../../services/http-error-message';

const emptyInventory: FurnitureInventory = {
  id: '',
  templateVersion: '',
  lines: [],
  missingCategories: [],
  absentCategories: [],
  legalWarnings: [],
  readyForLeaseDocument: false,
  frozen: false,
  privateAreas: [],
  version: 0,
};

@Component({
  selector: 'app-inventory-page',
  imports: [RouterLink],
  templateUrl: './inventory-page.html',
  styleUrl: './inventory-page.css',
})
export class InventoryPage {
  private readonly route = inject(ActivatedRoute);
  private readonly inventories = inject(ConditionReportService);
  readonly leaseId = this.route.snapshot.paramMap.get('leaseId') ?? '';
  readonly inventory = signal<FurnitureInventory>(emptyInventory);
  readonly loading = signal(true);
  readonly saving = signal(false);
  readonly error = signal('');
  readonly success = signal('');

  constructor() {
    this.load();
  }

  load(): void {
    this.loading.set(true);
    this.error.set('');
    this.success.set('');
    this.inventories
      .getInventory(this.leaseId)
      .pipe(rxFinalize(() => this.loading.set(false)))
      .subscribe({
        next: (inventory) => this.inventory.set(inventory),
        error: (error) =>
          this.error.set(
            httpErrorMessage(error, 'Impossible de charger l’inventaire du mobilier.'),
          ),
      });
  }

  updateText(
    id: string,
    field: 'privateAreaId' | 'designation' | 'description',
    event: Event,
  ): void {
    const value =
      event.target instanceof HTMLInputElement ||
      event.target instanceof HTMLTextAreaElement ||
      event.target instanceof HTMLSelectElement
        ? event.target.value
        : '';
    this.updateLine(id, { [field]: value });
  }

  updateQuantity(id: string, event: Event): void {
    const input = event.target instanceof HTMLInputElement ? event.target : null;
    const quantity =
      !input || input.value === '' || !Number.isFinite(input.valueAsNumber)
        ? -1
        : input.valueAsNumber;
    this.updateLine(id, { quantity });
  }

  updatePresence(id: string, event: Event): void {
    const line = this.inventory().lines.find((candidate) => candidate.id === id);
    const value = event.target instanceof HTMLSelectElement ? event.target.value : '';
    const presence: FurniturePresence | null =
      value === 'PRESENT' || value === 'ABSENT' ? value : null;
    if (!line?.category) return;
    this.updateLine(id, {
      presence,
      quantity:
        presence === 'ABSENT'
          ? 0
          : presence === 'PRESENT' && line.quantity === 0
            ? 1
            : line.quantity,
    });
  }

  addLine(): void {
    if (this.inventory().frozen || this.saving()) return;
    this.inventory.update((inventory) => ({
      ...inventory,
      lines: [
        ...inventory.lines,
        {
          id: crypto.randomUUID(),
          category: null,
          presence: null,
          privateAreaId: '',
          designation: '',
          quantity: 1,
          description: '',
        },
      ],
    }));
  }

  removeLine(id: string): void {
    if (this.inventory().frozen || this.saving()) return;
    this.inventory.update((inventory) => ({
      ...inventory,
      lines: inventory.lines.filter((line) => line.id !== id || line.category !== null),
    }));
  }

  warningLabel(category: string): string {
    return (
      this.inventory().lines.find((line) => line.category === category)?.designation ?? category
    );
  }

  save(): void {
    const inventory = this.inventory();
    if (inventory.frozen) {
      this.error.set('Cet inventaire est figé et ne peut plus être modifié.');
      return;
    }
    const validationError = this.validationError(inventory.lines);
    if (validationError) {
      this.error.set(validationError);
      return;
    }
    this.saving.set(true);
    this.error.set('');
    this.success.set('');
    this.inventories
      .saveInventory(this.leaseId, { version: inventory.version, lines: inventory.lines })
      .pipe(rxFinalize(() => this.saving.set(false)))
      .subscribe({
        next: (saved) => {
          this.inventory.set(saved);
          this.success.set('Inventaire enregistré.');
        },
        error: (error) =>
          this.error.set(httpErrorMessage(error, 'Impossible d’enregistrer l’inventaire.')),
      });
  }

  private updateLine(id: string, changes: Partial<FurnitureInventoryLine>): void {
    if (this.inventory().frozen || this.saving()) return;
    this.inventory.update((inventory) => ({
      ...inventory,
      lines: inventory.lines.map((line) => (line.id === id ? { ...line, ...changes } : line)),
    }));
  }

  private validationError(lines: FurnitureInventoryLine[]): string | null {
    for (const line of lines) {
      if (!line.privateAreaId.trim()) return 'Renseignez la zone de chaque ligne.';
      if (!line.designation.trim()) return 'Renseignez la désignation de chaque ligne.';
      if (!Number.isInteger(line.quantity) || line.quantity < 0) {
        return 'Saisissez une quantité entière positive ou nulle.';
      }
      if (line.category && line.presence === null) {
        return 'Déclarez la présence ou l’absence de chaque élément réglementaire.';
      }
      if (line.category && line.presence === 'PRESENT' && line.quantity === 0) {
        return 'Un élément réglementaire présent doit avoir une quantité positive.';
      }
      if (line.category && line.presence === 'ABSENT' && line.quantity !== 0) {
        return 'Un élément réglementaire absent doit avoir une quantité nulle.';
      }
    }
    return null;
  }
}