/** FEAT-2: Kontakte-Liste — Gridify-Namenssuche + Paging, Link auf Detailseite. */
import { useState } from 'react'
import { Link } from 'react-router-dom'
import { de } from '../strings/de'
import { listContactsPaged } from '../api/contacts'
import { condition, type GridifyQuery } from '../api/gridify'
import { useApi } from '../hooks/useApi'

const PAGE_SIZE = 20

export default function KontaktePage() {
  const t = de.pages.kontakte
  const [search, setSearch] = useState('')
  const [page, setPage] = useState(1)

  const filter = search.trim()
    ? condition({ field: 'name', op: 'contains', value: search.trim() })
    : undefined
  const query: GridifyQuery = { filter, orderBy: 'name', page, pageSize: PAGE_SIZE }

  const contacts = useApi(() => listContactsPaged(query), [filter, page])

  const total = contacts.data?.totalCount ?? 0
  const totalPages = Math.max(1, Math.ceil(total / PAGE_SIZE))
  const items = contacts.data?.items ?? []

  return (
    <section className="page">
      <header className="page-head">
        <div>
          <h2>{t.title}</h2>
          {contacts.data && (
            <p className="muted">
              {total} {t.countLabel}
            </p>
          )}
        </div>
        <Link to="/kontakte/neu" className="btn btn--primary">
          + {t.newButton}
        </Link>
      </header>

      <div className="filters">
        <input
          type="search"
          className="input"
          placeholder={t.searchPlaceholder}
          value={search}
          onChange={(e) => {
            setSearch(e.target.value)
            setPage(1)
          }}
          aria-label={t.fields.name}
        />
      </div>

      {contacts.loading && <p className="muted">{de.common.loading}</p>}
      {contacts.error && (
        <div className="alert alert--error">
          <span>{contacts.error}</span>
          <button type="button" className="btn" onClick={contacts.reload}>
            {de.common.retry}
          </button>
        </div>
      )}

      {!contacts.loading && !contacts.error && items.length === 0 && (
        <p className="muted">{t.empty}</p>
      )}

      {items.length > 0 && (
        <ul className="card-list">
          {items.map((c) => (
            <li key={c.id}>
              <Link to={`/kontakte/${c.id}`} className="gerbil-card">
                <span className="gerbil-card__name">{c.name}</span>
                <span className="gerbil-card__meta">
                  {[c.phone, c.email].filter(Boolean).join(' · ')}
                </span>
              </Link>
            </li>
          ))}
        </ul>
      )}

      {totalPages > 1 && (
        <nav className="pager" aria-label="Seitennavigation">
          <button
            type="button"
            className="btn"
            disabled={page <= 1}
            onClick={() => setPage((p) => Math.max(1, p - 1))}
          >
            {de.common.previous}
          </button>
          <span className="muted">
            {de.common.page} {page} {de.common.of} {totalPages}
          </span>
          <button
            type="button"
            className="btn"
            disabled={page >= totalPages}
            onClick={() => setPage((p) => Math.min(totalPages, p + 1))}
          >
            {de.common.next}
          </button>
        </nav>
      )}
    </section>
  )
}