import { Component, OnDestroy, OnInit } from '@angular/core';
import { CommonModule } from '@angular/common';
import { Subscription } from 'rxjs';
import { RouteState } from '../../../core/route-state/route';
import { PlanningExportService } from '../../../shared/services/planning-export.service';
import { summarizeDailyRoutes } from '../../../shared/utils/route-sequencing.utils';
import { RouteAssignedResponse } from '../../../core/models/route.model';

interface KpiSummary {
  totalPdvs: number;
  assignedPdvs: number;
  unassignedPdvs: number;
  coverage: number;
  users: number;
  days: number;
  totalDistance: number;
  totalTravelHours: number;
  averageDistance: number;
  averageTravelHours: number;
  totalWorkHours: number;
  averageRoutesPerUser: number;
  averageUtilization: number;
  assignmentBalance: number;
}

interface ReasonSummary {
  reason: string;
  count: number;
}

interface UserLoad {
  id: string;
  name: string;
  routes: number;
  distance: number;
  workHours: number;
  capacityHours: number;
  utilization: number;
  status: 'ok' | 'warning' | 'over-capacity';
  alertMessage: string;
}

@Component({
  standalone: true,
  selector: 'app-planning-kpis',
  imports: [CommonModule],
  templateUrl: './planning-kpis.component.html',
  styleUrl: './planning-kpis.component.css'
})
export class PlanningKpisComponent implements OnInit, OnDestroy {
  summary: KpiSummary = this.emptySummary();
  reasons: ReasonSummary[] = [];
  userLoads: UserLoad[] = [];
  hasData = false;

  private readonly subs: Subscription[] = [];

  constructor(
    private routeState: RouteState,
    private exportService: PlanningExportService
  ) {}

  ngOnInit(): void {
    this.subs.push(
      this.routeState.assignedRoutes$.subscribe(() => this.refresh()),
      this.routeState.noAssignedRoutes$.subscribe(() => this.refresh())
    );
  }

  ngOnDestroy(): void {
    this.subs.forEach(subscription => subscription.unsubscribe());
  }

  barWidth(value: number): number {
    return Math.min(Math.max(value, 0), 100);
  }

  utilizationClass(load: UserLoad): string {
    return load.status;
  }

  exportPlanning(): void {
    this.exportService.export();
  }

  private refresh(): void {
    const assigned = this.routeState.getAssignedSnapshot();
    const unassigned = this.routeState.getNoAssignedSnapshot();
    const totalPdvs = assigned.length + unassigned.length;
    const dailyRoutes = summarizeDailyRoutes(assigned);
    const totalDistance = dailyRoutes.reduce((sum, day) => sum + day.distanceKm, 0);
    const totalTravelHours = dailyRoutes.reduce((sum, day) => sum + day.travelHours, 0);
    const totalWorkHours = dailyRoutes.reduce((sum, day) => sum + day.workHours, 0);
    const users = new Set(assigned.map(route => String(route.json.usuario_id))).size;
    const days = new Set(assigned.map(route => route.json.dia)).size;
    const loads = new Map<string, UserLoad>();

    for (const route of assigned) {
      const key = String(route.json.usuario_id);
      const current = loads.get(key) ?? {
        id: key,
        name: route.json.nombre_usuario,
        routes: 0,
        distance: 0,
        workHours: 0,
        capacityHours: this.numberValue(route.json.hora_laboral_semanal_usuario),
        utilization: 0,
        status: 'ok',
        alertMessage: ''
      };
      current.routes++;
      // Sequential distance and work are aggregated per user below.
      loads.set(key, current);
    }

    this.userLoads = Array.from(loads.values()).map(load => {
      const userDays = dailyRoutes.filter(day => day.userId === load.id);
      load.distance = userDays.reduce((sum, day) => sum + day.distanceKm, 0);
      load.workHours = userDays.reduce((sum, day) => sum + day.workHours, 0);
      load.utilization = load.capacityHours ? (load.workHours / load.capacityHours) * 100 : 0;
      load.status = load.utilization > 100 ? 'over-capacity' : load.utilization > 90 ? 'warning' : 'ok';
      load.alertMessage = load.status === 'over-capacity'
        ? `Alerta: ${load.name} supera el 100% de su capacidad por carga (${load.workHours.toFixed(1)} h de ${load.capacityHours.toFixed(1)} h). Reasigna PDVs o reduce horas.`
        : load.status === 'warning'
          ? `${load.name} está sobre el 90% de su capacidad por carga (${load.workHours.toFixed(1)} h de ${load.capacityHours.toFixed(1)} h).`
          : `${load.name} está dentro de capacidad por carga (${load.workHours.toFixed(1)} h de ${load.capacityHours.toFixed(1)} h).`;
      return load;
    }).sort((a, b) => b.routes - a.routes || b.workHours - a.workHours);
    const routeCounts = this.userLoads.map(load => load.routes);
    const assignmentBalance = routeCounts.length ? Math.max(...routeCounts) - Math.min(...routeCounts) : 0;
    const averageUtilization = this.userLoads.length
      ? this.userLoads.reduce((sum, load) => sum + load.utilization, 0) / this.userLoads.length
      : 0;

    this.summary = {
      totalPdvs,
      assignedPdvs: assigned.length,
      unassignedPdvs: unassigned.length,
      coverage: totalPdvs ? (assigned.length / totalPdvs) * 100 : 0,
      users,
      days,
      totalDistance,
      totalTravelHours,
      averageDistance: assigned.length ? totalDistance / assigned.length : 0,
      averageTravelHours: assigned.length ? totalTravelHours / assigned.length : 0,
      totalWorkHours,
      averageRoutesPerUser: users ? assigned.length / users : 0,
      averageUtilization,
      assignmentBalance
    };

    const reasonCounts = new Map<string, number>();
    for (const route of unassigned) {
      const reason = route.motivo?.trim() || 'Sin motivo especificado';
      reasonCounts.set(reason, (reasonCounts.get(reason) ?? 0) + 1);
    }
    this.reasons = Array.from(reasonCounts.entries())
      .map(([reason, count]) => ({ reason, count }))
      .sort((a, b) => b.count - a.count);
    this.hasData = totalPdvs > 0;
  }

  private numberValue(value: number | string | null | undefined): number {
    const result = Number(value);
    return Number.isFinite(result) ? result : 0;
  }

  private emptySummary(): KpiSummary {
    return {
      totalPdvs: 0,
      assignedPdvs: 0,
      unassignedPdvs: 0,
      coverage: 0,
      users: 0,
      days: 0,
      totalDistance: 0,
      totalTravelHours: 0,
      averageDistance: 0,
      averageTravelHours: 0,
      totalWorkHours: 0,
      averageRoutesPerUser: 0,
      averageUtilization: 0,
      assignmentBalance: 0
    };
  }
}