import { AnimatePresence, motion } from "framer-motion";
import { useEffect, useState } from "react";
import { api } from "../lib/api";
import type { ShortLink } from "../lib/types";
import { prettyHost, shortUrl } from "../lib/format";
import { isValidUrl, normalizeUrl } from "../lib/shortcode";
import { Modal } from "./ui/Modal";
import { Button } from "./ui/Button";

interface Props {
  link: ShortLink | null;
  onClose: () => void;
  onSaved: (updated: ShortLink, message: string) => void;
}

export function EditLinkModal({ link, onClose, onSaved }: Props) {
  const open = Boolean(link);
  const [draft, setDraft] = useState("");
  const [busy, setBusy] = useState(false);
  const [error, setError] = useState<string | null>(null);

  // Reset the form whenever a different link opens the modal.
  useEffect(() => {
    setDraft(link?.longUrl ?? "");
    setError(null);
    setBusy(false);
  }, [link?.id, link?.longUrl]);

  if (!link) return <Modal open={false} onClose={onClose} children={null} />;

  const changed = normalizeUrl(draft) !== link.longUrl;

  async function save() {
    if (!link) return;
    if (!isValidUrl(draft)) {
      setError("That doesn't look like a valid URL.");
      return;
    }
    setBusy(true);
    setError(null);
    try {
      const updated = await api.updateLink(link.id, {
        longUrl: normalizeUrl(draft),
      });
      onSaved(updated, "Link updated");
    } catch (e) {
      setError(e instanceof Error ? e.message : "Could not save changes.");
      setBusy(false);
    }
  }

  return (
    <Modal open={open} onClose={onClose} title="Edit link">
      {/* Short code is permanent — shown read-only so existing shares keep working. */}
      <div className="-mt-2 mb-4 flex items-center justify-between gap-3 rounded-xl border border-line bg-surface-2 px-4 py-3">
        <div className="min-w-0">
          <p className="text-[11px] uppercase tracking-wide text-muted">Short link</p>
          <p className="truncate font-mono text-sm font-semibold text-ink">
            {shortUrl(link.code)}
          </p>
        </div>
        <span className="shrink-0 rounded-full border border-line px-2 py-0.5 text-[10px] text-muted">
          permanent
        </span>
      </div>

      <label className="mb-1.5 block text-[13px] font-medium text-muted">
        Destination URL
      </label>
      <input
        autoFocus
        value={draft}
        onChange={(e) => {
          setDraft(e.target.value);
          if (error) setError(null);
        }}
        onKeyDown={(e) => e.key === "Enter" && save()}
        spellCheck={false}
        className={`h-11 w-full rounded-xl border bg-surface-2 px-3.5 font-mono text-sm text-ink outline-none transition-colors ${
          error ? "border-red-400" : "border-line focus:border-[var(--ink)]"
        }`}
      />
      <p className="mt-2 text-xs text-muted">
        Currently points to {prettyHost(link.longUrl)}.
      </p>

      <AnimatePresence>
        {error && (
          <motion.p
            initial={{ opacity: 0, y: -4 }}
            animate={{ opacity: 1, y: 0 }}
            exit={{ opacity: 0 }}
            className="mt-3 text-[13px] font-medium text-red-500"
          >
            {error}
          </motion.p>
        )}
      </AnimatePresence>

      <div className="mt-5 flex items-center gap-2">
        <Button onClick={save} disabled={busy || !changed}>
          {busy ? "Saving…" : "Save changes"}
        </Button>
        <Button variant="ghost" onClick={onClose} disabled={busy}>
          Cancel
        </Button>
      </div>
    </Modal>
  );
}