"use client";

import { useState, useTransition } from "react";
import { useRouter } from "next/navigation";
import { Lead, Activity, Reminder, ClientTranscript } from "@/db/schema";
import { StatusBadge } from "@/components/ui/StatusBadge";
import { OptionMultiSelect } from "@/components/ui/option-multi-select";
import {
  addLeadTag,
  removeLeadTag,
  renameLeadTag,
  deleteTranscript,
  convertLeadToClient,
} from "@/app/admin/pipeline/actions";
import { formatDistanceToNow, format } from "date-fns";
import { it } from "date-fns/locale";
import Link from "next/link";
import {
  Mail,
  Phone,
  Clock,
  CalendarDays,
  Calendar,
  StickyNote,
  Mic,
  Trash2,
  Sparkles,
  type LucideIcon,
} from "lucide-react";
import { LogActivityModal } from "./LogActivityModal";
import { TranscriptModal } from "./TranscriptModal";
import { EditLeadModal } from "./LeadForm";

const ACTIVITY_META: Record<string, { label: string; Icon: LucideIcon }> = {
  call: { label: "Chiamata effettuata", Icon: Phone },
  email: { label: "E-mail inviata", Icon: Mail },
  meeting: { label: "Meeting", Icon: Calendar },
  note: { label: "Nota", Icon: StickyNote },
};

type TimelineItem =
  | { kind: "transcript"; date: Date; data: ClientTranscript }
  | { kind: "activity"; date: Date; data: Activity };

export function LeadDetail({
  lead,
  activities,
  reminders,
  tags,
  tagOptions,
  transcripts,
  convertedClientId,
}: {
  lead: Lead;
  activities: Activity[];
  reminders: Reminder[];
  tags: string[];
  tagOptions: string[];
  transcripts: ClientTranscript[];
  convertedClientId?: string | null;
}) {
  const router = useRouter();
  const [, startTransition] = useTransition();
  const [converting, startConvert] = useTransition();
  const [tagError, setTagError] = useState<string | null>(null);
  const [expandedIds, setExpandedIds] = useState<Set<string>>(new Set());
  const [deletingId, setDeletingId] = useState<string | null>(null);

  function handleConvert() {
    const ok = window.confirm(
      `Convertire "${lead.name}" in cliente?\n\nVerrà creato un cliente (con email, telefono e transcript del lead) e il lead verrà archiviato mantenendo lo stato "vinto".`
    );
    if (!ok) return;
    startConvert(() => convertLeadToClient(lead.id));
  }

  function run(fn: () => Promise<unknown>) {
    setTagError(null);
    startTransition(async () => {
      try {
        await fn();
        router.refresh();
      } catch (e) {
        setTagError(e instanceof Error ? e.message : "Errore nel salvataggio");
      }
    });
  }

  function toggleExpand(id: string) {
    setExpandedIds((prev) => {
      const next = new Set(prev);
      if (next.has(id)) next.delete(id);
      else next.add(id);
      return next;
    });
  }

  function handleDeleteTranscript(transcriptId: string) {
    setDeletingId(transcriptId);
    startTransition(async () => {
      try {
        await deleteTranscript(transcriptId, lead.id);
        router.refresh();
      } catch (e) {
        console.error("deleteTranscript error:", e);
      } finally {
        setDeletingId(null);
      }
    });
  }

  // Unified, reverse-chronological timeline of activities + transcripts.
  const timeline: TimelineItem[] = [
    ...activities.map((a) => ({
      kind: "activity" as const,
      date: new Date(a.activity_date),
      data: a,
    })),
    ...transcripts.map((t) => ({
      kind: "transcript" as const,
      date: new Date(t.call_date + "T00:00:00"),
      data: t,
    })),
  ].sort((a, b) => b.date.getTime() - a.date.getTime());

  return (
    <div className="flex flex-col gap-8">
      {/* Header + Actions */}
      <div className="flex flex-col lg:flex-row justify-between lg:items-start gap-6 border-b border-border pb-6">
        <div>
          <div className="flex items-center gap-3">
            <h1 className="text-2xl font-semibold tracking-tight text-foreground">
              {lead.name}
            </h1>
            <StatusBadge status={lead.status} />
          </div>
          <p className="text-sm font-medium text-muted-foreground mt-1">
            {lead.company || "Azienda non specificata"}
          </p>
        </div>

        <div className="flex flex-wrap items-center gap-2.5">
          <LogActivityModal leadId={lead.id} />
          <TranscriptModal leadId={lead.id} />

          {convertedClientId ? (
            <Link
              href={`/admin/clients/${convertedClientId}`}
              className="inline-flex items-center gap-2 px-4 py-2.5 border border-border text-primary hover:bg-muted text-xs font-semibold rounded-lg transition-colors"
            >
              ✓ Convertito → Apri cliente
            </Link>
          ) : (
            lead.status === "won" && (
              <button
                type="button"
                onClick={handleConvert}
                disabled={converting}
                className="inline-flex items-center gap-2 px-4 py-2.5 border border-border text-muted-foreground hover:text-foreground hover:bg-muted text-xs font-semibold rounded-lg transition-colors disabled:opacity-50"
              >
                {converting ? "Conversione..." : "Converti in cliente"}
              </button>
            )
          )}

          {/* Primary action */}
          <Link
            href={`/admin/preventivi/genera?lead_id=${lead.id}`}
            className="inline-flex items-center gap-2 px-5 py-2.5 bg-primary text-primary-foreground hover:bg-primary/90 text-xs font-medium tracking-wide rounded-lg shadow-sm transition-colors"
          >
            <Sparkles className="w-4 h-4" />
            Genera preventivo
          </Link>

          <EditLeadModal lead={lead} />
        </div>
      </div>

      {/* Body: asymmetric columns */}
      <div className="grid grid-cols-1 lg:grid-cols-3 gap-8 items-start">
        {/* Left (1/3): Profile card */}
        <div className="lg:col-span-1 bg-card border border-border rounded-xl p-6 shadow-card flex flex-col gap-6">
          <h3 className="text-xs font-bold uppercase tracking-wider text-muted-foreground">
            Profilo Lead
          </h3>

          <div className="space-y-4">
            <ProfileRow Icon={Mail} label="Email">
              {lead.email ? (
                <a
                  href={`mailto:${lead.email}`}
                  className="font-semibold text-foreground hover:text-primary transition-colors"
                >
                  {lead.email}
                </a>
              ) : (
                <span className="font-semibold text-muted-foreground">—</span>
              )}
            </ProfileRow>

            <ProfileRow Icon={Phone} label="Telefono">
              <span className="font-semibold text-foreground font-mono">
                {lead.phone || "—"}
              </span>
            </ProfileRow>

            <ProfileRow Icon={Clock} label="Ultimo contatto">
              <span className="font-semibold text-foreground">
                {lead.last_contact_date
                  ? formatDistanceToNow(new Date(lead.last_contact_date), {
                      addSuffix: true,
                      locale: it,
                    })
                  : "—"}
              </span>
            </ProfileRow>

            <ProfileRow Icon={CalendarDays} label="Prossima azione programmata">
              <span
                className={
                  lead.next_action
                    ? "font-semibold text-foreground"
                    : "font-semibold text-muted-foreground"
                }
              >
                {lead.next_action || "—"}
              </span>
            </ProfileRow>
          </div>

          {/* Tags */}
          <div className="border-t border-border pt-5">
            <p className="text-[10px] uppercase font-bold text-muted-foreground tracking-wider mb-2.5">
              Tag Lead
            </p>
            <OptionMultiSelect
              values={tags}
              options={tagOptions}
              onAdd={(v) => run(() => addLeadTag(lead.id, v))}
              onRemove={(v) => run(() => removeLeadTag(lead.id, v))}
              onRename={(o, n) => run(() => renameLeadTag(o, n))}
            />
            {tagError && <p className="text-xs text-destructive mt-1">{tagError}</p>}
          </div>
        </div>

        {/* Right (2/3): Note, Follow-up, Timeline */}
        <div className="lg:col-span-2 flex flex-col gap-6">
          <div className="grid grid-cols-1 md:grid-cols-2 gap-6">
            {/* Note */}
            <div className="bg-card border border-border rounded-xl p-5 shadow-card">
              <h3 className="text-xs font-bold uppercase tracking-wider text-muted-foreground mb-3">
                Note
              </h3>
              {lead.notes ? (
                <div className="text-xs text-foreground/80 leading-relaxed min-h-[80px] p-2.5 bg-muted/50 rounded-lg border border-border">
                  {lead.notes}
                </div>
              ) : (
                <div className="flex items-center justify-center min-h-[80px] text-[11px] font-medium text-muted-foreground p-2.5 bg-muted/50 rounded-lg border border-border">
                  Nessuna nota
                </div>
              )}
            </div>

            {/* Next follow-up */}
            <div className="bg-card border border-border rounded-xl p-5 shadow-card">
              <h3 className="text-xs font-bold uppercase tracking-wider text-muted-foreground mb-3">
                Prossimo Follow-up
              </h3>
              {reminders.length > 0 ? (
                <ul className="space-y-2.5">
                  {reminders.map((r) => (
                    <li
                      key={r.id}
                      className="border-l-2 border-primary/40 pl-2.5 text-xs"
                    >
                      <p className="font-semibold text-foreground">{r.title}</p>
                      <p className="text-muted-foreground font-mono text-[11px] mt-0.5">
                        {format(new Date(r.due_date), "dd MMM yyyy", { locale: it })}
                      </p>
                    </li>
                  ))}
                </ul>
              ) : (
                <div className="flex flex-col items-center justify-center min-h-[80px] border border-dashed border-border rounded-lg text-muted-foreground p-3">
                  <Clock className="w-5 h-5 mb-1.5 text-muted-foreground/60" />
                  <span className="text-[11px] font-medium">
                    Nessun reminder impostato
                  </span>
                </div>
              )}
            </div>
          </div>

          {/* Unified timeline */}
          <div className="bg-card border border-border rounded-xl p-6 shadow-card">
            <h3 className="text-xs font-bold uppercase tracking-wider text-muted-foreground mb-6">
              Storico delle Interazioni
            </h3>

            {timeline.length > 0 ? (
              <div className="relative space-y-6">
                {/* vertical connector line */}
                <div className="absolute top-2 bottom-2 left-[19px] w-px bg-border z-0" />

                {timeline.map((item) => {
                  if (item.kind === "transcript") {
                    const t = item.data;
                    const isExpanded = expandedIds.has(t.id);
                    const isLong =
                      t.content.length > 140 || t.content.split("\n").length > 2;
                    return (
                      <div
                        key={`t-${t.id}`}
                        className="relative z-10 pl-10 flex gap-4 items-start group"
                      >
                        <div className="absolute left-0 w-10 h-10 rounded-full bg-primary text-primary-foreground flex items-center justify-center shadow">
                          <Mic className="w-4 h-4" />
                        </div>
                        <div className="flex-1 bg-muted border border-border rounded-xl p-4 hover:border-muted-foreground/30 transition-colors">
                          <div className="flex flex-wrap justify-between items-start gap-2 mb-2">
                            <div>
                              <span className="text-[10px] font-bold text-primary uppercase tracking-wide">
                                Transcript Chiamata AI
                              </span>
                              {t.title && (
                                <h4 className="text-xs font-bold text-foreground">
                                  {t.title}
                                </h4>
                              )}
                            </div>
                            <div className="flex items-center gap-2">
                              <span className="text-[10px] text-muted-foreground font-mono">
                                {format(new Date(t.call_date + "T00:00:00"), "d MMMM yyyy", {
                                  locale: it,
                                })}
                              </span>
                              <button
                                type="button"
                                onClick={() => handleDeleteTranscript(t.id)}
                                disabled={deletingId === t.id}
                                aria-label="Elimina transcript"
                                className="opacity-0 group-hover:opacity-100 text-muted-foreground hover:text-destructive transition-all disabled:opacity-50"
                              >
                                <Trash2 className="w-3.5 h-3.5" />
                              </button>
                            </div>
                          </div>
                          <div className="text-xs text-foreground/80 leading-relaxed pt-2 border-t border-border/60">
                            <p
                              className={
                                isExpanded ? "whitespace-pre-wrap" : "line-clamp-2"
                              }
                            >
                              {t.content}
                            </p>
                            {isLong && (
                              <button
                                type="button"
                                onClick={() => toggleExpand(t.id)}
                                className="text-[11px] font-bold text-primary hover:text-primary/80 mt-2 inline-flex items-center gap-1"
                              >
                                {isExpanded ? "Mostra meno" : "Mostra tutto"}
                              </button>
                            )}
                          </div>
                        </div>
                      </div>
                    );
                  }

                  const a = item.data;
                  const meta = ACTIVITY_META[a.type] ?? ACTIVITY_META.note;
                  const Icon = meta.Icon;
                  return (
                    <div
                      key={`a-${a.id}`}
                      className="relative z-10 pl-10 flex gap-4 items-start"
                    >
                      <div className="absolute left-0 w-10 h-10 rounded-full bg-muted text-muted-foreground border border-border flex items-center justify-center">
                        <Icon className="w-4 h-4" />
                      </div>
                      <div className="flex-1 border border-border rounded-xl p-4 hover:border-muted-foreground/30 transition-colors">
                        <div className="flex justify-between items-center gap-2 mb-1.5">
                          <span className="text-[10px] font-bold text-muted-foreground uppercase tracking-wide">
                            {meta.label}
                          </span>
                          <span className="text-[10px] text-muted-foreground font-mono">
                            {formatDistanceToNow(new Date(a.activity_date), {
                              addSuffix: true,
                              locale: it,
                            })}
                          </span>
                        </div>
                        {a.notes && (
                          <p className="text-xs text-muted-foreground leading-relaxed">
                            {a.notes}
                          </p>
                        )}
                        {a.duration_minutes && (
                          <p className="text-[11px] text-muted-foreground/70 font-mono mt-1.5">
                            Durata: {a.duration_minutes} min
                          </p>
                        )}
                      </div>
                    </div>
                  );
                })}
              </div>
            ) : (
              <p className="text-sm text-muted-foreground text-center py-6">
                Nessuna interazione registrata
              </p>
            )}
          </div>
        </div>
      </div>
    </div>
  );
}

function ProfileRow({
  Icon,
  label,
  children,
}: {
  Icon: LucideIcon;
  label: string;
  children: React.ReactNode;
}) {
  return (
    <div className="flex items-center gap-3.5 text-xs">
      <div className="p-2 bg-muted text-muted-foreground rounded-lg shrink-0">
        <Icon className="w-4 h-4" />
      </div>
      <div className="min-w-0">
        <p className="text-[10px] text-muted-foreground font-medium">{label}</p>
        {children}
      </div>
    </div>
  );
}