{#
   Partial: the parameter rows for one reducer.
   Expects: reducer_key (str) OR default_reducer (on first render)
            spec (dict)       OR default_spec
#}
{% set rk = reducer_key if reducer_key is defined else default_reducer %}
{% set s  = spec        if spec        is defined else default_spec %}

{% if not s %}
  <p class="flash err">No reducers available — no supported package importable.</p>
{% else %}

  <div class="form-grid">
    {% for name, kind, default, choices, help in s.key %}
      {% set locked = (name in ('n_components', 'n_dims')) %}
      <label for="embed__{{ name }}">
        {{ name }}
        {% if help %}<span class="hint">{{ help }}</span>{% endif %}
      </label>

      {% if kind == 'bool' %}
        <span>
          <input type="checkbox" id="embed__{{ name }}" name="embed__{{ name }}"
                 {% if default %}checked{% endif %} />
        </span>
      {% elif choices %}
        <select id="embed__{{ name }}" name="embed__{{ name }}">
          {% for c in choices %}
            <option value="{{ c }}" {% if c == default %}selected{% endif %}>{{ c if c != "" else "(none)" }}</option>
          {% endfor %}
        </select>
      {% elif kind == 'int' %}
        <input type="number" step="1" id="embed__{{ name }}" name="embed__{{ name }}"
               value="{{ default }}" {% if locked %}readonly{% endif %} />
      {% elif kind == 'float' %}
        <input type="number" step="any" id="embed__{{ name }}" name="embed__{{ name }}"
               value="{{ default }}" />
      {% elif kind == 'int_or_null' %}
        <input type="text" id="embed__{{ name }}" name="embed__{{ name }}"
               value="{{ default }}" placeholder="int or empty" />
      {% else %}
        <input type="text" id="embed__{{ name }}" name="embed__{{ name }}"
               value="{{ default }}" />
      {% endif %}
    {% endfor %}
  </div>

  {% if s.advanced %}
    <details class="advanced">
      <summary>show advanced</summary>
      <div class="advanced-body">
        <div class="form-grid">
          {% for name, kind, default, choices, help in s.advanced %}
            <label for="embed__{{ name }}">
              {{ name }}
              {% if help %}<span class="hint">{{ help }}</span>{% endif %}
            </label>

            {% if kind == 'bool' %}
              <span>
                <input type="checkbox" id="embed__{{ name }}" name="embed__{{ name }}"
                       {% if default %}checked{% endif %} />
              </span>
            {% elif choices %}
              <select id="embed__{{ name }}" name="embed__{{ name }}">
                {% for c in choices %}
                  <option value="{{ c }}" {% if c == default %}selected{% endif %}>{{ c if c != "" else "(none)" }}</option>
                {% endfor %}
              </select>
            {% elif kind == 'int' %}
              <input type="number" step="1" id="embed__{{ name }}" name="embed__{{ name }}"
                     value="{{ default }}" />
            {% elif kind == 'float' %}
              <input type="number" step="any" id="embed__{{ name }}" name="embed__{{ name }}"
                     value="{{ default }}" />
            {% elif kind == 'int_or_null' %}
              <input type="text" id="embed__{{ name }}" name="embed__{{ name }}"
                     value="{{ default }}" placeholder="int or empty" />
            {% else %}
              <input type="text" id="embed__{{ name }}" name="embed__{{ name }}"
                     value="{{ default }}" />
            {% endif %}
          {% endfor %}
        </div>
      </div>
    </details>
  {% endif %}

{% endif %}