// components/RegistrationDocuments.tsx
// Client-side panel for managing a registration's `documents` field:
//   - Lists current files with download links
//   - Provides an upload form for the 5 post-wizard document types:
//     Cor9.1 (name reserved letter), Cor9.4, Director Acceptance, Resolution,
//     CIPC Registration, MOI
//
// All uploads go to /api/register/[id]/upload, which renames the file
// server-side per the type and appends it to the reg's `documents` array.

"use client";

import { useEffect, useState } from "react";

type DocType =
  | "cipc_reservation"
  | "cipc_approval"
  | "director_acceptance"
  | "resolution"
  | "cipc_registration"
  | "moi";

const TYPE_LABELS: Record<DocType, string> = {
  cipc_reservation: "Cor9.1 — Name Reservation letter",
  cipc_approval: "Cor9.4 — Name Approval letter",
  director_acceptance: "Director Acceptance letter",
  resolution: "Resolution to start company",
  cipc_registration: "CIPC Registration document",
  moi: "MOI from CIPC",
};

const TYPE_PREFIX: Record<DocType, string> = {
  cipc_reservation: "Cor9.1",
  cipc_approval: "Cor9.4",
  director_acceptance: "Director Acceptance",
  resolution: "Resolution",
  cipc_registration: "CIPC Registration",
  moi: "MOI",
};

interface PBFile {
  name: string;
  originalName?: string;
}

function extractFiles(documents: unknown): PBFile[] {
  if (!documents) return [];
  if (Array.isArray(documents)) {
    return documents
      .map((d) => {
        if (typeof d === "string") return { name: d };
        if (d && typeof d === "object" && "name" in (d as Record<string, unknown>)) {
          return { name: String((d as Record<string, unknown>).name) };
        }
        return null;
      })
      .filter((x): x is PBFile => !!x);
  }
  return [];
}

export default function RegistrationDocuments({
  registrationId,
  initialDocuments,
  cipcReservedName,
}: {
  registrationId: string;
  initialDocuments: unknown;
  cipcReservedName?: string;
}) {
  const [docs, setDocs] = useState<PBFile[]>(extractFiles(initialDocuments));
  const [type, setType] = useState<DocType>("cipc_reservation");
  const [file, setFile] = useState<File | null>(null);
  const [busy, setBusy] = useState(false);
  const [msg, setMsg] = useState<{ kind: "ok" | "err"; text: string } | null>(null);

  // Refresh the file list every time the component remounts
  useEffect(() => {
    setDocs(extractFiles(initialDocuments));
  }, [initialDocuments]);

  async function handleUpload(e: React.FormEvent) {
    e.preventDefault();
    if (!file) {
      setMsg({ kind: "err", text: "Pick a file first." });
      return;
    }
    setBusy(true);
    setMsg(null);
    try {
      const fd = new FormData();
      fd.append("type", type);
      if (cipcReservedName) fd.append("reserved_name", cipcReservedName);
      fd.append("files", file);
      const res = await fetch(`/api/register/${registrationId}/upload`, {
        method: "POST",
        body: fd,
      });
      const data = await res.json().catch(() => ({}));
      if (!res.ok) throw new Error(data.error || `HTTP ${res.status}`);
      // Append the new file to local state (server didn't return per-file names
      // in a stable shape, so we just re-fetch by triggering a page refresh).
      setFile(null);
      setMsg({ kind: "ok", text: `Uploaded ${data.filesUploaded || 1} file(s). Reloading…` });
      setTimeout(() => window.location.reload(), 800);
    } catch (err: unknown) {
      setMsg({ kind: "err", text: err instanceof Error ? err.message : "Upload failed" });
    } finally {
      setBusy(false);
    }
  }

  return (
    <div className="bg-surface border border-border rounded-lg p-5 space-y-4">
      <div>
        <p className="text-xs uppercase tracking-[0.08em] text-muted font-bold mb-2">Documents</p>
        {docs.length === 0 ? (
          <p className="text-xs text-muted italic">No documents uploaded yet.</p>
        ) : (
          <ul className="space-y-1.5">
            {docs.map((d, i) => (
              <li key={i} className="flex items-center justify-between gap-3 text-sm">
                <span className="font-mono text-fg truncate">{d.name}</span>
                <a
                  href={`/api/register/${registrationId}/file?name=${encodeURIComponent(d.name)}`}
                  target="_blank"
                  rel="noreferrer"
                  className="text-xs text-accent hover:underline"
                >
                  Download
                </a>
              </li>
            ))}
          </ul>
        )}
      </div>

      <form onSubmit={handleUpload} className="border-t border-border pt-4 space-y-3">
        <p className="text-xs uppercase tracking-[0.08em] text-muted font-bold">Upload document</p>
        <div className="grid grid-cols-1 sm:grid-cols-2 gap-3">
          <div>
            <label className="text-xs font-semibold text-muted mb-1 block">Type</label>
            <select
              value={type}
              onChange={(e) => setType(e.target.value as DocType)}
              className="w-full bg-surface border border-border rounded px-3 py-2 text-sm text-fg focus:outline-none focus:border-accent"
            >
              {(Object.keys(TYPE_LABELS) as DocType[]).map((k) => (
                <option key={k} value={k}>
                  {TYPE_LABELS[k]} → {TYPE_PREFIX[k]} - {cipcReservedName || "..."}
                </option>
              ))}
            </select>
            {cipcReservedName && (
              <p className="text-[10px] text-muted mt-1 font-mono">
                Will save as: {TYPE_PREFIX[type]} - {cipcReservedName}.&lt;ext&gt;
              </p>
            )}
          </div>
          <div>
            <label className="text-xs font-semibold text-muted mb-1 block">File (PDF / JPG / PNG, ≤ 10 MB)</label>
            <input
              type="file"
              accept="application/pdf,image/jpeg,image/png"
              onChange={(e) => setFile(e.target.files?.[0] || null)}
              className="block w-full text-sm text-fg file:mr-3 file:py-1.5 file:px-3 file:rounded file:border file:border-border file:bg-surface-warm file:text-fg file:text-xs file:font-semibold file:cursor-pointer hover:file:bg-accent/10"
            />
          </div>
        </div>
        <div className="flex items-center gap-3">
          <button
            type="submit"
            disabled={busy || !file}
            className="px-4 py-2 rounded-md border border-accent bg-accent text-accent-on text-sm font-bold disabled:opacity-40 hover:opacity-90"
          >
            {busy ? "Uploading…" : "Upload"}
          </button>
          {msg && (
            <span className={msg.kind === "ok" ? "text-xs text-success" : "text-xs text-danger"}>
              {msg.text}
            </span>
          )}
        </div>
      </form>
    </div>
  );
}