// ---- Color Controls ----

const targetColor = U.obs();
const randomizeTargetColor = () => {
  targetColor.value = d3
    .hsl(Math.random() * 360, Math.random(), Math.random())
    .formatHex();
};

U.element("colorSelect", ({ randomButton }, form) => {
  U.field(form.elements.colorText, { obs: targetColor });
  U.field(form.elements.colorPicker, { obs: targetColor });
  U.form(form);
  randomButton.addEventListener("click", randomizeTargetColor);
});

targetColor.subscribe((hex, { previous }) => {
  const style = document.querySelector(":root").style;
  style.setProperty("--background", hex);
  style.setProperty("--highlight", getContrastingTextColor(hex));

  if (previous) {
    const prevButton = document.createElement("button");
    prevButton.innerText = previous;
    const { h, s, l } = d3.hsl(previous);
    prevButton.style = `
      color: ${getContrastingTextColor(previous)}; 
      --button-bg: ${previous};
      --button-bg-hover: ${d3.hsl(h, s, clamp(0.25, l * 1.25, 0.9)).formatHex()};
    `;
    prevButton.addEventListener("click", () => (targetColor.value = previous));
    document.getElementById("prevColors").prepend(prevButton);
  }
});

randomizeTargetColor();

// ---- Metric Controls ----

const addMetricForm = (formName, legendText, initialKind, initialMetric) => {
  const metricKind = U.obs(initialKind);
  let metric;

  U.template("metric-select-template", ({ form, legend }) => {
    form.name = formName;
    legend.innerText = legendText;
    form.elements[initialKind].disabled = false;
    form.elements[initialKind].value = initialMetric;
    form.elements.metricKind.value = initialKind;

    U.reactive(() => {
      form.elements.whole.disabled = metricKind.value !== "whole";
      form.elements.mean.disabled = metricKind.value !== "mean";
      form.elements.stat.disabled = metricKind.value !== "stat";
    });

    const metrics = U.obs([
      U.field(form.elements.whole),
      U.field(form.elements.mean),
      U.field(form.elements.stat),
    ]);

    U.form(form, {
      onChange: {
        metricKind(kind) {
          metricKind.value = kind;
        },
      },
    });

    metric = U.obs(() => {
      const [whole, mean, stat] = metrics.value;
      return { whole, mean, stat }[metricKind.value];
    });

    return "sidebar";
  });

  return metric;
};

const sortMetric = addMetricForm("sortMetric", "Sort Metric", "whole", "alpha");
const clsMetric = addMetricForm("clsMetric", "Cluster Metric", "stat", "importance");

// ---- Sorting Function Controls ----

// terrible hack
const getMetricSymbol = (metric) =>
  document.querySelector(`option[value=${metric}]`).textContent.at(-2);
const sortMetricSymbol = U.obs(() => getMetricSymbol(sortMetric.value));
const clsMetricSymbol = U.obs(() => getMetricSymbol(clsMetric.value));

const setupMinMaxWithLabel = (checkboxField, labelElem, maxLabel, minLabel) => {
  const sortOrderToggle = U.field(checkboxField);
  const sortOrder = U.obs(() => (sortOrderToggle.value ? maxLabel : minLabel));
  U.reactive(() => {
    labelElem.innerText = sortOrder.value;
  });
  return sortOrder;
};

U.template(
  "function-template",
  ({ form, minmaxLabel, metricSymbol, metricSymbolCls, clusterName, clusterNameInv }) => {
    form.name = "sortFunction";

    form.elements.useWholeImage.checked = true;
    form.elements.totalSize.checked = true;
    form.elements.useBestCluster.checked = true;
    form.elements.invClusterSize.checked = true;

    const sortOrder = setupMinMaxWithLabel(
      form.elements.sortOrder,
      minmaxLabel,
      "max",
      "min"
    );

    // TODO field controls for the rest of the toggles

    U.reactive(() => {
      metricSymbol.innerText = sortMetricSymbol.value;
      metricSymbolCls.innerText = `${sortMetricSymbol.value}(B)`;
    });

    clusterName.innerText = clusterNameInv.innerText = "B";

    U.form(form);

    return "sidebar";
  }
);

U.template(
  "function-template",
  ({
    form,
    minmaxLabel,
    useWholeImageLabel,
    metricSymbolCls,
    clusterName,
    clusterNameInv,
  }) => {
    form.name = "clusterFunction";

    form.elements.sortOrder.checked = true;

    const sortOrder = setupMinMaxWithLabel(
      form.elements.sortOrder,
      minmaxLabel,
      "argmax",
      "argmin"
    );

    // TODO field controls for the rest of the toggles

    // not needed for cluster function
    useWholeImageLabel.nextSibling.remove();
    useWholeImageLabel.remove();
    // and this can't be disabled so just replace the field with the span
    metricSymbolCls.parentElement.replaceWith(metricSymbolCls);

    U.reactive(() => {
      metricSymbolCls.innerText = `${clsMetricSymbol.value}(K)`;
    });

    clusterName.innerText = clusterNameInv.innerText = "K";

    U.form(form);

    return "sidebar";
  }
);