"use client";

import { Icon } from "@/components/icons";
import type { QrFormProps } from "@/components/qr-forms/types";
import { Button, Field, TextArea, TextInput } from "@/components/ui";
import { MAX_LINKS, type LinkEntry } from "@/lib/qr/types/links";

/**
 * Liest die Linkliste aus den Formulardaten heraus.
 *
 * Die Daten kommen als `QrFormData` — ein flaches Objekt ohne Garantien.
 * Beim Bearbeiten eines gespeicherten Codes stammen sie aus der Datenbank und
 * können nach einer Schema-Änderung unvollständig sein; deshalb hier prüfen
 * statt annehmen.
 */
function readLinks(value: unknown): LinkEntry[] {
  if (!Array.isArray(value)) return [{ label: "", url: "" }];
  const entries = value.map((entry) => {
    const record = (entry ?? {}) as Record<string, unknown>;
    return {
      label: typeof record.label === "string" ? record.label : "",
      url: typeof record.url === "string" ? record.url : "",
    };
  });
  return entries.length > 0 ? entries : [{ label: "", url: "" }];
}

export function LinksForm({ value, onChange, error, disabled }: QrFormProps) {
  const title = typeof value.title === "string" ? value.title : "";
  const description =
    typeof value.description === "string" ? value.description : "";
  const links = readLinks(value.links);

  const setLinks = (next: LinkEntry[]) => onChange({ ...value, links: next });

  const updateLink = (index: number, patch: Partial<LinkEntry>) =>
    setLinks(links.map((link, i) => (i === index ? { ...link, ...patch } : link)));

  const move = (index: number, direction: -1 | 1) => {
    const target = index + direction;
    if (target < 0 || target >= links.length) return;
    const next = [...links];
    [next[index], next[target]] = [next[target], next[index]];
    setLinks(next);
  };

  return (
    <div className="space-y-5">
      <Field
        label="Überschrift der Seite"
        htmlFor="links-title"
        hint="Steht groß über der Linkliste, z. B. der Projektname."
      >
        <TextInput
          id="links-title"
          value={title}
          disabled={disabled}
          maxLength={80}
          placeholder="Projekt Nordwind"
          onChange={(event) => onChange({ ...value, title: event.target.value })}
        />
      </Field>

      <Field
        label="Kurzer Text (optional)"
        htmlFor="links-description"
        hint="Eine Zeile zur Einordnung — was findet man hier?"
      >
        <TextArea
          id="links-description"
          rows={2}
          value={description}
          disabled={disabled}
          maxLength={300}
          placeholder="Alle Unterlagen zum Projekt auf einen Blick."
          onChange={(event) =>
            onChange({ ...value, description: event.target.value })
          }
        />
      </Field>

      <div>
        <div className="mb-2 flex items-baseline justify-between gap-3">
          <span className="text-sm font-medium text-slate-700">Links</span>
          <span className="text-xs text-slate-500">
            {links.length} von {MAX_LINKS}
          </span>
        </div>

        <ul className="space-y-3">
          {links.map((link, index) => (
            <li
              key={index}
              className="rounded-xl border border-slate-200 bg-slate-50/70 p-3"
            >
              <div className="flex items-start gap-2">
                <div className="min-w-0 flex-1 space-y-2">
                  <TextInput
                    aria-label={`Beschriftung von Link ${index + 1}`}
                    value={link.label}
                    disabled={disabled}
                    maxLength={80}
                    placeholder="Beschriftung, z. B. Preisliste"
                    onChange={(event) =>
                      updateLink(index, { label: event.target.value })
                    }
                  />
                  <TextInput
                    aria-label={`Adresse von Link ${index + 1}`}
                    inputMode="url"
                    spellCheck={false}
                    value={link.url}
                    disabled={disabled}
                    maxLength={2048}
                    placeholder="https://example.com/preisliste.pdf"
                    onChange={(event) =>
                      updateLink(index, { url: event.target.value })
                    }
                  />
                </div>

                <div className="flex shrink-0 flex-col gap-0.5">
                  <button
                    type="button"
                    disabled={disabled || index === 0}
                    onClick={() => move(index, -1)}
                    aria-label={`Link ${index + 1} nach oben`}
                    className="rounded-md p-1.5 text-slate-500 transition-colors hover:bg-white hover:text-slate-900 disabled:cursor-not-allowed disabled:opacity-30 disabled:hover:bg-transparent"
                  >
                    <Icon name="arrowLeft" className="size-4 rotate-90" />
                  </button>
                  <button
                    type="button"
                    disabled={disabled || index === links.length - 1}
                    onClick={() => move(index, 1)}
                    aria-label={`Link ${index + 1} nach unten`}
                    className="rounded-md p-1.5 text-slate-500 transition-colors hover:bg-white hover:text-slate-900 disabled:cursor-not-allowed disabled:opacity-30 disabled:hover:bg-transparent"
                  >
                    <Icon name="arrowLeft" className="size-4 -rotate-90" />
                  </button>
                  <button
                    type="button"
                    disabled={disabled || links.length === 1}
                    onClick={() => setLinks(links.filter((_, i) => i !== index))}
                    aria-label={`Link ${index + 1} entfernen`}
                    className="rounded-md p-1.5 text-slate-500 transition-colors hover:bg-white hover:text-red-600 disabled:cursor-not-allowed disabled:opacity-30 disabled:hover:bg-transparent"
                  >
                    <Icon name="trash" className="size-4" />
                  </button>
                </div>
              </div>
            </li>
          ))}
        </ul>

        {links.length < MAX_LINKS ? (
          <Button
            type="button"
            variant="secondary"
            size="sm"
            disabled={disabled}
            onClick={() => setLinks([...links, { label: "", url: "" }])}
            className="mt-3"
          >
            Link hinzufügen
          </Button>
        ) : null}

        {error ? (
          <p role="alert" className="mt-2 text-sm text-red-600">
            {error}
          </p>
        ) : null}
      </div>
    </div>
  );
}