// components/ResolutionExplorer.tsx
// Client Component. 4-section menu for company registration,
// director resignation, director appointment, and resolutions.
// Only Company Registration is active; others are placeholders.

"use client";

import { useState, useRef, useEffect, useCallback } from "react";
import type { ComponentProps } from "react";
import type {
  PBList,
  YsterbaardResolution,
  ResolutionStatus,
} from "@/lib/types";
import StatusBadge from "@/components/StatusBadge";
import { useRouter } from "next/navigation";

type Section = "company_registration" | "director_resignation" | "director_appointment" | "resolution_appointment";

const SECTIONS: { id: Section; label: string }[] = [
  { id: "company_registration",             label: "1 — Company registration" },
  { id: "director_resignation",             label: "2 — Director resignation" },
  { id: "director_appointment",             label: "3 — Director appointment acceptance" },
  { id: "resolution_appointment",          label: "4 — Resolution appointment and resignation" },
];

type BadgeVariant = ComponentProps<typeof StatusBadge>["variant"];

function statusVariant(s: ResolutionStatus): BadgeVariant {
  switch (s) {
    case "draft":     return "muted";
    case "pending":   return "warn";
    case "completed": return "success";
    case "archived":  return "muted";
  }
}

function formatDate(iso: string | null): string {
  if (!iso) return "—";
  return new Date(iso).toLocaleDateString("en-ZA", {
    day: "2-digit", month: "short", year: "numeric",
  });
}

interface Props {
  resolutions: PBList<YsterbaardResolution>;
}

interface RegSearchItem {
  id: string;
  reference_name: string;
  status: string;
  proposed_name_1: string;
}

export default function ResolutionExplorer({ resolutions }: Props) {
  const router = useRouter();
  const [activeSection, setActiveSection] = useState<Section>("company_registration");
  const [showNewDialog, setShowNewDialog] = useState(false);
  const [newRegName, setNewRegName] = useState("");
  const [newRegLoading, setNewRegLoading] = useState(false);
  const [generatedLink, setGeneratedLink] = useState<string | null>(null);
  const [dialogError, setDialogError] = useState<string | null>(null);
  const [linkCopied, setLinkCopied] = useState(false);

  // Search state
  const [searchQuery, setSearchQuery] = useState("");
  const [searchResults, setSearchResults] = useState<RegSearchItem[]>([]);
  const [searchLoading, setSearchLoading] = useState(false);
  const [searchFocused, setSearchFocused] = useState(false);
  const searchRef = useRef<HTMLDivElement>(null);
  const searchTimeout = useRef<ReturnType<typeof setTimeout> | null>(null);

  const filteredResolutions = resolutions.items
    .filter((r) => r.type === activeSection)
    .sort((a, b) => new Date(b.created).getTime() - new Date(a.created).getTime());

  // Close search dropdown when clicking outside
  useEffect(() => {
    const handler = (e: MouseEvent) => {
      if (searchRef.current && !searchRef.current.contains(e.target as Node)) {
        setSearchFocused(false);
      }
    };
    document.addEventListener("mousedown", handler);
    return () => document.removeEventListener("mousedown", handler);
  }, []);

  // Search registrations as user types
  const doSearch = useCallback(async (q: string) => {
    if (q.trim().length === 0) { setSearchResults([]); setSearchLoading(false); return; }
    setSearchLoading(true);
    try {
      const res = await fetch(`/api/register/search?q=${encodeURIComponent(q.trim())}&fields=id,reference_name,status,proposed_name_1`);
      if (!res.ok) throw new Error();
      const data = await res.json();
      setSearchResults(data.items || []);
    } catch { setSearchResults([]); }
    finally { setSearchLoading(false); }
  }, []);

  const handleSearchChange = (e: React.ChangeEvent<HTMLInputElement>) => {
    const q = e.target.value;
    setSearchQuery(q);
    if (searchTimeout.current) clearTimeout(searchTimeout.current);
    if (!q.trim()) { setSearchResults([]); setSearchLoading(false); return; }
    setSearchLoading(true);
    searchTimeout.current = setTimeout(() => doSearch(q), 300);
  };

  const handleSelectExisting = (reg: RegSearchItem) => {
    setSearchFocused(false);
    setShowNewDialog(false);
    router.push(`/register/${reg.id}?prefill=1`);
  };

  const handleCreateRegistration = async () => {
    if (!newRegName.trim()) return;
    setNewRegLoading(true);
    setDialogError(null);
    try {
      const res = await fetch("/api/register/create", {
        method: "POST",
        headers: { "Content-Type": "application/json" },
        body: JSON.stringify({ reference_name: newRegName.trim() }),
      });
      if (!res.ok) throw new Error(await res.text());
      const data = await res.json();
      setGeneratedLink(`${window.location.origin}/register/${data.id}`);
    } catch (err: unknown) {
      setDialogError(err instanceof Error ? err.message : "Failed to create link");
    } finally {
      setNewRegLoading(false);
    }
  };

  const openNewDialog = () => {
    setNewRegName(""); setGeneratedLink(null); setDialogError(null);
    setSearchQuery(""); setSearchResults([]);
    setShowNewDialog(true);
  };

  return (
    <div className="container-x py-8 space-y-6">
      {/* 4 Section Buttons */}
      <div className="grid grid-cols-2 lg:grid-cols-4 gap-3">
        {SECTIONS.map((sec) => {
          const isActive = activeSection === sec.id;
          const isDisabled = sec.id !== "company_registration";
          return (
            <button
              key={sec.id}
              onClick={() => { if (!isDisabled) setActiveSection(sec.id); }}
              className={
                "px-4 py-5 rounded-lg border text-sm font-semibold text-center transition-all " +
                (isDisabled
                  ? "bg-surface border-border text-muted cursor-not-allowed opacity-50"
                  : isActive
                    ? "bg-accent border-accent text-accent-on shadow-sm"
                    : "bg-surface border-border text-fg hover:border-accent hover:text-accent")
              }
            >
              {sec.label}
            </button>
          );
        })}
      </div>

      {/* ── Company Registration ── */}
      {activeSection === "company_registration" && (
        <div className="space-y-6">
          {/* Header + New button */}
          <div className="flex items-center justify-between">
            <p className="text-sm font-semibold text-fg">
              {filteredResolutions.length === 0 ? "No registrations yet" : `${filteredResolutions.length} registration${filteredResolutions.length === 1 ? "" : "s"}`}
            </p>
            <button
              onClick={openNewDialog}
              className="px-4 py-2 bg-accent text-accent-on rounded font-semibold text-sm hover:opacity-90 transition-opacity"
            >
              + New registration
            </button>
          </div>

          {/* Registration search bar */}
          <div ref={searchRef} className="relative">
            <label className="block text-xs font-semibold text-muted uppercase tracking-wider mb-1.5">
              Search submitted registrations
            </label>
            <div className="flex gap-2">
              <div className="relative flex-1">
                <input
                  className="w-full bg-surface border border-border rounded px-3 py-2.5 pr-10 text-sm text-fg placeholder-muted focus:outline-none focus:border-accent transition-colors"
                  placeholder="Search by reference or company name..."
                  value={searchQuery}
                  onChange={handleSearchChange}
                  onFocus={() => setSearchFocused(true)}
                />
                {searchLoading && (
                  <div className="absolute right-3 top-1/2 -translate-y-1/2">
                    <svg className="w-4 h-4 animate-spin text-muted" fill="none" viewBox="0 0 24 24">
                      <circle className="opacity-25" cx="12" cy="12" r="10" stroke="currentColor" strokeWidth="4" />
                      <path className="opacity-75" fill="currentColor" d="M4 12a8 8 0 018-8V0C5.373 0 0 5.373 0 12h4z" />
                    </svg>
                  </div>
                )}
              </div>
              <a
                href="/registrations"
                className="flex-shrink-0 px-4 py-2 bg-surface border border-border rounded text-sm font-semibold text-fg hover:border-accent hover:text-accent no-underline transition-colors text-center"
              >
                View all →
              </a>
            </div>

            {/* Search results dropdown */}
            {searchFocused && searchResults.length > 0 && (
              <div className="absolute z-10 top-full left-0 right-0 mt-1 bg-surface border border-border rounded-lg shadow-xl overflow-hidden max-h-72 overflow-y-auto">
                {searchResults.map((reg) => (
                  <button
                    key={reg.id}
                    onClick={() => handleSelectExisting(reg)}
                    className="w-full text-left px-4 py-3 hover:bg-surface-warm transition-colors border-b border-border last:border-b-0"
                  >
                    <div className="flex items-start justify-between gap-2">
                      <div className="min-w-0">
                        <p className="text-sm font-semibold text-fg truncate">{reg.reference_name || reg.id}</p>
                        <p className="text-xs text-muted truncate">{reg.proposed_name_1 || "No company name"}</p>
                      </div>
                      <span className={`flex-shrink-0 inline-flex px-2 py-0.5 rounded text-xs font-semibold ${
                        reg.status === "submitted"
                          ? "bg-accent/10 text-accent"
                          : "bg-surface border border-border text-muted"
                      }`}>
                        {reg.status === "submitted" ? "Submitted" : "Draft"}
                      </span>
                    </div>
                  </button>
                ))}
              </div>
            )}

            {searchFocused && !searchLoading && searchQuery.trim() && searchResults.length === 0 && (
              <div className="absolute z-10 top-full left-0 right-0 mt-1 bg-surface border border-border rounded-lg shadow-xl px-4 py-3 text-sm text-muted">
                No registrations found for &ldquo;{searchQuery}&rdquo;
              </div>
            )}
          </div>

          {/* Resolutions list (draft/pending resolutions for company_registration) */}
          {filteredResolutions.length > 0 && (
            <div className="bg-surface border border-border rounded-lg overflow-hidden">
              <table className="w-full text-sm">
                <thead>
                  <tr className="border-b border-border bg-surface-warm">
                    <th className="text-left px-5 py-3 text-xs font-semibold text-muted uppercase tracking-wide">Title</th>
                    <th className="text-left px-5 py-3 text-xs font-semibold text-muted uppercase tracking-wide hidden md:table-cell">Client</th>
                    <th className="text-left px-5 py-3 text-xs font-semibold text-muted uppercase tracking-wide hidden lg:table-cell">ID / Ref</th>
                    <th className="text-left px-5 py-3 text-xs font-semibold text-muted uppercase tracking-wide">Status</th>
                    <th className="text-left px-5 py-3 text-xs font-semibold text-muted uppercase tracking-wide hidden sm:table-cell">Date</th>
                  </tr>
                </thead>
                <tbody className="divide-y divide-border-soft">
                  {filteredResolutions.map((r) => (
                    <tr key={r.id} className="hover:bg-surface-warm transition-colors">
                      <td className="px-5 py-4"><span className="font-semibold text-fg">{r.title ?? "—"}</span></td>
                      <td className="px-5 py-4 hidden md:table-cell"><span className="text-fg-2">{r.client_name ?? "—"}</span></td>
                      <td className="px-5 py-4 hidden lg:table-cell"><span className="font-mono text-xs text-muted">{r.client_id_no ?? "—"}</span></td>
                      <td className="px-5 py-4"><StatusBadge variant={statusVariant(r.status)}>{r.status}</StatusBadge></td>
                      <td className="px-5 py-4 hidden sm:table-cell"><span className="text-muted tabular-nums text-xs">{formatDate(r.resolution_date ?? r.created)}</span></td>
                    </tr>
                  ))}
                </tbody>
              </table>
            </div>
          )}
        </div>
      )}

      {/* ── Other sections (placeholder) ── */}
      {activeSection !== "company_registration" && (
        <div className="bg-surface border border-border rounded-lg p-12 text-center text-muted text-sm">
          This section is under development.
        </div>
      )}

      {/* New Registration Dialog */}
      {showNewDialog && (
        <div className="fixed inset-0 z-50 flex items-center justify-center bg-black/50 backdrop-blur-sm">
          <div className="bg-surface border border-border rounded-xl shadow-2xl w-full max-w-md mx-4 overflow-hidden">
            <div className="border-b border-border bg-surface-warm px-6 py-4">
              <h2 className="text-fg font-semibold text-lg">New registration</h2>
              <p className="text-muted text-sm mt-0.5">Give this registration a reference name so you can find it later.</p>
            </div>

            <div className="p-6 space-y-4">
              {!generatedLink ? (
                <>
                  <div>
                    <label className="block text-sm font-semibold text-fg mb-1.5">Reference name</label>
                    <input
                      className="w-full bg-surface border border-border rounded px-3 py-2.5 text-sm text-fg placeholder-muted focus:outline-none focus:border-accent transition-colors"
                      placeholder="e.g. Company A — Smith family"
                      value={newRegName}
                      onChange={(e) => setNewRegName(e.target.value)}
                      onKeyDown={(e) => { if (e.key === "Enter") handleCreateRegistration(); }}
                      autoFocus
                    />
                  </div>
                  {dialogError && <p className="text-danger text-sm">{dialogError}</p>}
                </>
              ) : (
                <div className="space-y-3">
                  <p className="text-sm text-fg font-semibold">Share this link with your client:</p>
                  <div className="flex gap-2">
                    <input readOnly className="flex-1 bg-surface border border-border rounded px-3 py-2 text-sm text-fg font-mono" value={generatedLink} />
                    <button
                      onClick={() => {
                        const el = document.createElement("textarea");
                        el.value = generatedLink ?? "";
                        el.style.position = "fixed";
                        el.style.opacity = "0";
                        document.body.appendChild(el);
                        el.focus();
                        el.select();
                        const ok = document.execCommand("copy");
                        document.body.removeChild(el);
                        if (ok) { setLinkCopied(true); setTimeout(() => setLinkCopied(false), 2000); }
                      }}
                      className="px-4 py-2 bg-accent text-accent-on rounded font-semibold text-sm flex-shrink-0"
                    >
                      {linkCopied ? "✓ Copied" : "Copy"}
                    </button>
                    {typeof navigator !== "undefined" && navigator.share ? (
                      <button
                        onClick={() => {
                          navigator.share({
                            title: "Company Registration",
                            text: "Please complete your company registration here:",
                            url: generatedLink ?? "",
                          }).catch(() => {});
                        }}
                        className="px-4 py-2 bg-surface border border-border text-fg rounded font-semibold text-sm flex-shrink-0 hover:bg-surface-warm transition-colors"
                      >
                        Share
                      </button>
                    ) : null}
                  </div>
                  <p className="text-xs text-muted">
                    Send this link to your client. They will fill in the director, company and shareholder details. You will be notified on Telegram when they submit.
                  </p>
                </div>
              )}
            </div>

            <div className="border-t border-border px-6 py-4 flex justify-end gap-3">
              {!generatedLink ? (
                <>
                  <button onClick={() => setShowNewDialog(false)} className="px-4 py-2 text-sm font-semibold text-muted hover:text-fg transition-colors">Cancel</button>
                  <button
                    onClick={handleCreateRegistration}
                    disabled={!newRegName.trim() || newRegLoading}
                    className="px-4 py-2 bg-accent text-accent-on rounded font-semibold text-sm disabled:opacity-40 hover:opacity-90 transition-opacity"
                  >
                    {newRegLoading ? "Creating..." : "Create link"}
                  </button>
                </>
              ) : (
                <button onClick={() => setShowNewDialog(false)} className="px-4 py-2 bg-accent text-accent-on rounded font-semibold text-sm hover:opacity-90 transition-opacity">
                  Done
                </button>
              )}
            </div>
          </div>
        </div>
      )}
    </div>
  );
}