"use client";

import { useEffect, useState } from "react";
import { useSession } from "next-auth/react";
import { redirect, useRouter } from "next/navigation";
import Link from "next/link";
import AuthenticatedLayout from "@/components/AuthenticatedLayout";
import { AppointmentStatusBadge } from "@/components/appointments/AppointmentStatusBadge";
import { Button } from "@/components/ui/button";
import { Card, CardContent, CardDescription, CardHeader, CardTitle } from "@/components/ui/card";
import { Avatar, AvatarFallback, AvatarImage } from "@/components/ui/avatar";
import { Separator } from "@/components/ui/separator";
import {
  Dialog,
  DialogContent,
  DialogDescription,
  DialogFooter,
  DialogHeader,
  DialogTitle,
} from "@/components/ui/dialog";
import { Textarea } from "@/components/ui/textarea";
import { Label } from "@/components/ui/label";
import { ApproveAppointmentModal } from "@/components/appointments/ApproveAppointmentModal";
import {
  Calendar,
  Clock,
  User,
  FileText,
  Video,
  CheckCircle2,
  XCircle,
  ArrowLeft,
  Loader2,
  AlertCircle,
} from "lucide-react";
import { format } from "date-fns";
import { es } from "date-fns/locale";
import { toast } from "sonner";
import type { Appointment } from "@/types/appointments";
import { canJoinMeeting, getAppointmentTimeStatus } from "@/utils/appointments";

interface PageProps {
  params: Promise<{ id: string }>;
}

export default function AppointmentDetailPage({ params }: PageProps) {
  const router = useRouter();
  const { data: session, status } = useSession();
  const [appointment, setAppointment] = useState<Appointment | null>(null);
  const [loading, setLoading] = useState(true);
  const [approveDialog, setApproveDialog] = useState(false);
  const [rejectDialog, setRejectDialog] = useState(false);
  const [motivoRechazo, setMotivoRechazo] = useState("");
  const [actionLoading, setActionLoading] = useState(false);
  const [appointmentId, setAppointmentId] = useState<string>("");

  useEffect(() => {
    const loadParams = async () => {
      const resolvedParams = await params;
      setAppointmentId(resolvedParams.id);
    };
    loadParams();
  }, [params]);

  useEffect(() => {
    if (!appointmentId) return;

    const fetchAppointment = async () => {
      try {
        const response = await fetch(`/api/appointments/${appointmentId}`);
        if (!response.ok) {
          throw new Error("No se pudo cargar la cita");
        }
        const data: Appointment = await response.json();
        setAppointment(data);
      } catch (error) {
        toast.error("Error al cargar la cita");
        console.error(error);
      } finally {
        setLoading(false);
      }
    };

    fetchAppointment();
  }, [appointmentId]);

  if (status === "loading" || loading) {
    return (
      <AuthenticatedLayout>
        <div className="flex items-center justify-center min-h-screen">
          <Loader2 className="h-8 w-8 animate-spin" />
        </div>
      </AuthenticatedLayout>
    );
  }

  if (!session) {
    redirect("/auth/login");
  }

  if (!appointment) {
    return (
      <AuthenticatedLayout>
        <div className="container mx-auto px-4 py-6">
          <Card>
            <CardContent className="flex flex-col items-center justify-center py-12">
              <AlertCircle className="h-12 w-12 text-muted-foreground mb-4" />
              <h3 className="text-lg font-semibold mb-2">Cita no encontrada</h3>
              <p className="text-muted-foreground mb-4">
                La cita que buscas no existe o no tienes permisos para verla.
              </p>
              <Button asChild>
                <Link href="/appointments">Volver a mis citas</Link>
              </Button>
            </CardContent>
          </Card>
        </div>
      </AuthenticatedLayout>
    );
  }

  const userRole = session.user.role as "PATIENT" | "DOCTOR" | "ADMIN";
  const isPatient = userRole === "PATIENT";
  const isDoctor = userRole === "DOCTOR";
  const otherUser = isPatient ? appointment.medico : appointment.paciente;
  const hasFecha = appointment.fechaSolicitada !== null;
  const fecha = hasFecha ? new Date(appointment.fechaSolicitada!) : null;

  const handleApprove = async (fechaSolicitada: Date, notas?: string) => {
    setActionLoading(true);
    try {
      const response = await fetch(`/api/appointments/${appointment.id}/approve`, {
        method: "POST",
        headers: {
          "Content-Type": "application/json",
        },
        body: JSON.stringify({
          fechaSolicitada: fechaSolicitada.toISOString(),
          notas,
        }),
      });

      if (!response.ok) {
        const error = await response.json();
        throw new Error(error.error || "Error al aprobar la cita");
      }

      const updated: Appointment = await response.json();
      setAppointment(updated);
      setApproveDialog(false);
      toast.success("Cita aprobada exitosamente");
    } catch (error) {
      toast.error(error instanceof Error ? error.message : "Error al aprobar la cita");
      console.error(error);
    } finally {
      setActionLoading(false);
    }
  };

  const handleRejectConfirm = async () => {
    if (!motivoRechazo.trim()) return;

    setActionLoading(true);
    try {
      const response = await fetch(`/api/appointments/${appointment.id}/reject`, {
        method: "POST",
        headers: { "Content-Type": "application/json" },
        body: JSON.stringify({ motivoRechazo }),
      });

      if (!response.ok) throw new Error("Error al rechazar la cita");

      const updated: Appointment = await response.json();
      setAppointment(updated);
      setRejectDialog(false);
      setMotivoRechazo("");
      toast.success("Cita rechazada");
    } catch (error) {
      toast.error("Error al rechazar la cita");
      console.error(error);
    } finally {
      setActionLoading(false);
    }
  };

  const handleCancel = async () => {
    setActionLoading(true);
    try {
      const response = await fetch(`/api/appointments/${appointment.id}`, {
        method: "DELETE",
      });

      if (!response.ok) throw new Error("Error al cancelar la cita");

      toast.success("Cita cancelada exitosamente");
      router.push("/appointments");
    } catch (error) {
      toast.error("Error al cancelar la cita");
      console.error(error);
      setActionLoading(false);
    }
  };

  const handleStartMeeting = async () => {
    setActionLoading(true);
    try {
      const response = await fetch(`/api/appointments/${appointment.id}/start-meeting`, {
        method: "POST",
      });

      if (!response.ok) {
        const error = await response.json();
        throw new Error(error.message || error.error || "No se puede iniciar la videollamada");
      }

      const data = await response.json();
      
      // Redirigir a la sala de Jitsi
      router.push(`/appointments/${appointment.id}/meet`);
    } catch (error) {
      toast.error(error instanceof Error ? error.message : "Error al iniciar videollamada");
      console.error(error);
    } finally {
      setActionLoading(false);
    }
  };

  const handleComplete = async () => {
    setActionLoading(true);
    try {
      const response = await fetch(`/api/appointments/${appointment.id}/complete`, {
        method: "POST",
      });

      if (!response.ok) throw new Error("Error al completar la cita");

      const updated: Appointment = await response.json();
      setAppointment(updated);
      toast.success("Cita marcada como completada");
    } catch (error) {
      toast.error("Error al completar la cita");
      console.error(error);
    } finally {
      setActionLoading(false);
    }
  };

  return (
    <AuthenticatedLayout>
      <div className="container mx-auto px-4 py-6 max-w-4xl">
        {/* Back Button */}
        <Button
          variant="ghost"
          className="mb-4"
          onClick={() => router.back()}
        >
          <ArrowLeft className="h-4 w-4 mr-2" />
          Volver
        </Button>

        {/* Header Card */}
        <Card className="mb-6">
          <CardHeader>
            <div className="flex items-center justify-between">
              <div className="flex items-center gap-4">
                {otherUser && (
                  <Avatar className="h-16 w-16">
                    <AvatarImage src={otherUser.profileImage || undefined} />
                    <AvatarFallback className="text-lg">
                      {otherUser.name[0]}{otherUser.lastname[0]}
                    </AvatarFallback>
                  </Avatar>
                )}
                <div>
                  <CardTitle className="text-2xl">
                    {otherUser
                      ? `${otherUser.name} ${otherUser.lastname}`
                      : isDoctor
                      ? "Sin asignar"
                      : "Médico por asignar"}
                  </CardTitle>
                  <CardDescription>
                    {isPatient ? "Médico asignado" : "Paciente"}
                  </CardDescription>
                </div>
              </div>
              <AppointmentStatusBadge status={appointment.estado} />
            </div>
          </CardHeader>
        </Card>

        {/* Details Card */}
        <Card className="mb-6">
          <CardHeader>
            <CardTitle>Detalles de la Cita</CardTitle>
          </CardHeader>
          <CardContent className="space-y-4">
            {hasFecha && fecha ? (
              <div className="grid grid-cols-1 md:grid-cols-2 gap-4">
                <div className="flex items-start gap-3">
                  <Calendar className="h-5 w-5 text-muted-foreground mt-0.5" />
                  <div>
                    <p className="text-sm font-medium">Fecha</p>
                    <p className="text-sm text-muted-foreground">
                      {format(fecha, "PPP", { locale: es })}
                    </p>
                  </div>
                </div>
                <div className="flex items-start gap-3">
                  <Clock className="h-5 w-5 text-muted-foreground mt-0.5" />
                  <div>
                    <p className="text-sm font-medium">Hora</p>
                    <p className="text-sm text-muted-foreground">
                      {format(fecha, "p", { locale: es })}
                    </p>
                  </div>
                </div>
              </div>
            ) : (
              <div className="bg-muted/50 p-4 rounded-lg">
                <div className="flex items-start gap-3">
                  <Clock className="h-5 w-5 text-muted-foreground mt-0.5" />
                  <div>
                    <p className="text-sm font-medium">Fecha y hora</p>
                    <p className="text-sm text-muted-foreground italic">
                      {appointment.estado === "PENDIENTE"
                        ? "Pendiente de asignación por el médico"
                        : "No asignada"}
                    </p>
                  </div>
                </div>
              </div>
            )}

            <Separator />

            <div className="flex items-start gap-3">
              <FileText className="h-5 w-5 text-muted-foreground mt-0.5" />
              <div className="flex-1">
                <p className="text-sm font-medium mb-1">Motivo de consulta</p>
                <p className="text-sm text-muted-foreground">
                  {appointment.motivoConsulta}
                </p>
              </div>
            </div>

            {appointment.motivoRechazo && (
              <>
                <Separator />
                <div className="bg-destructive/10 p-4 rounded-lg">
                  <div className="flex items-start gap-3">
                    <XCircle className="h-5 w-5 text-destructive mt-0.5" />
                    <div className="flex-1">
                      <p className="text-sm font-medium text-destructive mb-1">
                        Motivo de rechazo
                      </p>
                      <p className="text-sm text-muted-foreground">
                        {appointment.motivoRechazo}
                      </p>
                    </div>
                  </div>
                </div>
              </>
            )}

            {/* Solo mostrar sala si NO está completada */}
            {appointment.roomName && appointment.estado !== "COMPLETADA" && (
              <>
                <Separator />
                <div className="bg-primary/10 p-4 rounded-lg">
                  <div className="flex items-start gap-3">
                    <Video className="h-5 w-5 text-primary mt-0.5" />
                    <div className="flex-1">
                      <p className="text-sm font-medium mb-1">Sala de videollamada</p>
                      <p className="text-sm text-muted-foreground mb-3">
                        La sala está lista. Puedes unirte cuando llegue la hora de la cita.
                      </p>
                      <Button asChild size="sm">
                        <Link href={`/appointments/${appointment.id}/meet`}>
                          <Video className="h-4 w-4 mr-2" />
                          Unirse a la consulta
                        </Link>
                      </Button>
                    </div>
                  </div>
                </div>
              </>
            )}

            {appointment.notasGuardadas && appointment.notasConsulta && (
              <>
                <Separator />
                <div className="bg-green-50 dark:bg-green-950 p-4 rounded-lg">
                  <div className="flex items-start gap-3">
                    <FileText className="h-5 w-5 text-green-700 dark:text-green-400 mt-0.5" />
                    <div className="flex-1">
                      <p className="text-sm font-medium text-green-900 dark:text-green-100 mb-1">
                        Notas de la Consulta
                      </p>
                      {appointment.notasGuardadasAt && (
                        <p className="text-xs text-green-700 dark:text-green-300 mb-2">
                          Guardadas el {format(new Date(appointment.notasGuardadasAt), "d 'de' MMMM 'a las' HH:mm", { locale: es })}
                        </p>
                      )}
                      <div className="text-sm text-green-900 dark:text-green-100 whitespace-pre-wrap bg-white/50 dark:bg-black/20 p-3 rounded">
                        {appointment.notasConsulta}
                      </div>
                    </div>
                  </div>
                </div>
              </>
            )}
          </CardContent>
        </Card>

        {/* Actions Card */}
        <Card>
          <CardHeader>
            <CardTitle>Acciones</CardTitle>
          </CardHeader>
          <CardContent>
            <div className="flex flex-wrap gap-3">
              {isDoctor && appointment.estado === "PENDIENTE" && (
                <>
                  <Button
                    onClick={() => setApproveDialog(true)}
                    disabled={actionLoading}
                    className="flex-1 min-w-[150px]"
                  >
                    {actionLoading ? (
                      <Loader2 className="h-4 w-4 mr-2 animate-spin" />
                    ) : (
                      <CheckCircle2 className="h-4 w-4 mr-2" />
                    )}
                    Aprobar Cita
                  </Button>
                  <Button
                    onClick={() => setRejectDialog(true)}
                    variant="destructive"
                    disabled={actionLoading}
                    className="flex-1 min-w-[150px]"
                  >
                    <XCircle className="h-4 w-4 mr-2" />
                    Rechazar Cita
                  </Button>
                </>
              )}

              {isDoctor && appointment.estado === "APROBADA" && (
                <>
                  {canJoinMeeting(appointment.fechaSolicitada).canJoin ? (
                    <Button
                      onClick={handleStartMeeting}
                      disabled={actionLoading}
                      className="flex-1 min-w-[150px]"
                    >
                      {actionLoading ? (
                        <Loader2 className="h-4 w-4 mr-2 animate-spin" />
                      ) : (
                        <Video className="h-4 w-4 mr-2" />
                      )}
                      Unirse a Videollamada
                    </Button>
                  ) : (
                    <Button
                      disabled
                      variant="outline"
                      className="flex-1 min-w-[150px]"
                    >
                      <Clock className="h-4 w-4 mr-2" />
                      {getAppointmentTimeStatus(appointment.fechaSolicitada)}
                    </Button>
                  )}
                  <Button
                    onClick={handleComplete}
                    disabled={actionLoading}
                    variant="outline"
                    className="flex-1 min-w-[150px]"
                  >
                    {actionLoading ? (
                      <Loader2 className="h-4 w-4 mr-2 animate-spin" />
                    ) : (
                      <CheckCircle2 className="h-4 w-4 mr-2" />
                    )}
                    Marcar como Completada
                  </Button>
                </>
              )}

              {isPatient && appointment.estado === "PENDIENTE" && (
                <Button
                  onClick={handleCancel}
                  variant="outline"
                  disabled={actionLoading}
                  className="flex-1 min-w-[150px]"
                >
                  {actionLoading ? (
                    <Loader2 className="h-4 w-4 mr-2 animate-spin" />
                  ) : (
                    <XCircle className="h-4 w-4 mr-2" />
                  )}
                  Cancelar Cita
                </Button>
              )}

              {isPatient && appointment.estado === "APROBADA" && (
                <>
                  {canJoinMeeting(appointment.fechaSolicitada).canJoin ? (
                    <Button
                      onClick={handleStartMeeting}
                      disabled={actionLoading}
                      className="flex-1 min-w-[150px]"
                    >
                      {actionLoading ? (
                        <Loader2 className="h-4 w-4 mr-2 animate-spin" />
                      ) : (
                        <Video className="h-4 w-4 mr-2" />
                      )}
                      Unirse a Videollamada
                    </Button>
                  ) : (
                    <Button
                      disabled
                      variant="outline"
                      className="flex-1 min-w-[150px]"
                    >
                      <Clock className="h-4 w-4 mr-2" />
                      {getAppointmentTimeStatus(appointment.fechaSolicitada)}
                    </Button>
                  )}
                </>
              )}

              {/* Acciones para citas completadas */}
              {appointment.estado === "COMPLETADA" && (
                <>
                  {appointment.notasGuardadas && appointment.notasConsulta ? (
                    <div className="flex-1 min-w-[150px] bg-green-50 dark:bg-green-950 p-4 rounded-lg">
                      <div className="flex items-center gap-2 mb-2">
                        <CheckCircle2 className="h-5 w-5 text-green-600 dark:text-green-400" />
                        <p className="text-sm font-medium text-green-900 dark:text-green-100">
                          Consulta Finalizada
                        </p>
                      </div>
                      <p className="text-xs text-green-700 dark:text-green-300 mb-3">
                        Las notas de la consulta están disponibles arriba
                      </p>
                    </div>
                  ) : (
                    <div className="flex-1 min-w-[150px] bg-muted p-4 rounded-lg">
                      <div className="flex items-center gap-2 mb-2">
                        <CheckCircle2 className="h-5 w-5 text-muted-foreground" />
                        <p className="text-sm font-medium">
                          Consulta Finalizada
                        </p>
                      </div>
                      <p className="text-xs text-muted-foreground">
                        Esta cita ha sido completada
                      </p>
                    </div>
                  )}
                </>
              )}

              {/* Botón genérico de unirse (solo para APROBADA, no COMPLETADA) */}
              {appointment.estado === "APROBADA" && canJoinMeeting(appointment.fechaSolicitada).canJoin && (
                <Button asChild className="flex-1 min-w-[150px]">
                  <Link href={`/appointments/${appointment.id}/meet`}>
                    <Video className="h-4 w-4 mr-2" />
                    Unirse a la Consulta
                  </Link>
                </Button>
              )}
            </div>
          </CardContent>
        </Card>

        {/* Reject Dialog */}
        <Dialog open={rejectDialog} onOpenChange={setRejectDialog}>
          <DialogContent>
            <DialogHeader>
              <DialogTitle>Rechazar Cita</DialogTitle>
              <DialogDescription>
                Por favor proporciona un motivo para rechazar esta cita. El paciente recibirá esta información.
              </DialogDescription>
            </DialogHeader>
            <div className="space-y-2">
              <Label htmlFor="motivo">Motivo del rechazo</Label>
              <Textarea
                id="motivo"
                value={motivoRechazo}
                onChange={(e) => setMotivoRechazo(e.target.value)}
                placeholder="Ejemplo: No hay disponibilidad en esta fecha, por favor reagenda para la próxima semana..."
                rows={4}
                className="resize-none"
              />
            </div>
            <DialogFooter>
              <Button
                variant="outline"
                onClick={() => {
                  setRejectDialog(false);
                  setMotivoRechazo("");
                }}
              >
                Cancelar
              </Button>
              <Button
                variant="destructive"
                onClick={handleRejectConfirm}
                disabled={!motivoRechazo.trim() || actionLoading}
              >
                {actionLoading ? (
                  <Loader2 className="h-4 w-4 mr-2 animate-spin" />
                ) : (
                  <XCircle className="h-4 w-4 mr-2" />
                )}
                Rechazar Cita
              </Button>
            </DialogFooter>
          </DialogContent>
        </Dialog>

        {/* Approve Dialog */}
        <ApproveAppointmentModal
          open={approveDialog}
          onClose={() => setApproveDialog(false)}
          onConfirm={handleApprove}
          isLoading={actionLoading}
        />
      </div>
    </AuthenticatedLayout>
  );
}