// ---- Math and Utilities ----
// Vector Math
const vectorDot = (u, v) => u.map((x, i) => x * v[i]).reduce((x, y) => x + y);
const vectorMag = v => Math.sqrt(vectorDot(v, v));

// Angle Math
const rad2deg = 180 / Math.PI;

// Misc
const clamp = (mn, v, mx) => Math.min(Math.max(v, mn), mx);
const productLift =
  (...factors) =>
  (...args) =>
    factors
      .filter(fn => !!fn)
      .map(fn => fn(...args))
      .reduce((x, y) => x * y, 1);

// Contrast + Shadow + Hover Colors
const getContrastingTextColor = hex => {
  const { r, g, b } = d3.color(hex);
  return vectorDot([r, g, b], [0.3, 0.6, 0.1]) >= 128
    ? "var(--color-dark)"
    : "var(--color-light)";
};

// "Visual Importance"
const calcImportance = (chroma, lightness, proportion) =>
  chroma +
  Math.tanh(100 * (chroma - 0.25)) + // penalty for being <25%
  Math.tanh(100 * (chroma - 0.4)) + // penalty for being <40%
  lightness +
  Math.tanh(100 * (lightness - 0.5)) + // penalty for being <50%
  proportion +
  Math.tanh(100 * (proportion - 0.05)) + // penalty for being <5%
  Math.tanh(100 * (proportion - 0.1)) + // penalty for being <15%
  Math.tanh(100 * (proportion - 0.15)) + // penalty for being <15%
  Math.tanh(100 * (proportion - 0.25)) + // penalty for being <25%
  Math.tanh(100 * (proportion - 0.8)); // penalty for being <50%

// Conversions
const jab2hex = jab => d3.jab(...jab).formatHex();
const rgb2hex = rgb => d3.rgb(...rgb).formatHex();
const jab2hue = jab => d3.jch(d3.jab(...jab)).h || 0;
const rgb2hue = rgb => d3.hsl(d3.rgb(...rgb)).h || 0;
const jab2lit = ([j]) => j / 100;
const rgb2lit = rgb => d3.hsl(d3.rgb(...rgb)).l || 0;
const jab2chroma = jab => d3.jch(d3.jab(...jab)).C / 100;
const rgb2chroma = rgb => d3.jch(d3.rgb(...rgb)).C / 100;

// Pre-computation
const buildVectorData = (vector, toHue, toLightness, toChroma, toHex) => {
  const sqMag = vectorDot(vector, vector);
  const mag = Math.sqrt(sqMag);
  const unit = vector.map(c => c / mag);
  const hue = toHue(vector);
  const lightness = toLightness(vector);
  const chroma = toChroma(vector);
  const hex = toHex(vector);
  return { vector, sqMag, mag, unit, hue, lightness, chroma, hex };
};
const buildVectorDataJab = vector =>
  buildVectorData(vector, jab2hue, jab2lit, jab2chroma, jab2hex);
const buildVectorDataRgb = vector =>
  buildVectorData(vector, rgb2hue, rgb2lit, rgb2chroma, rgb2hex);

const buildClusterData = (
  size,
  inertia,
  mu1,
  mu2,
  mu3,
  nu1,
  nu2,
  nu3,
  totalSize,
  buildVectorDataForSpace
) => {
  const mu = buildVectorDataForSpace([mu1, mu2, mu3]);
  const nu = [nu1, nu2, nu3];
  const muNuAngle = rad2deg * Math.acos(vectorDot(mu.unit, nu) / vectorMag(nu));
  const proportion = size / totalSize;
  const importance = calcImportance(mu.chroma, mu.lightness, proportion);
  return {
    size,
    inverseSize: 1 / size,
    inertia,
    mu,
    nu,
    muNuAngle,
    proportion,
    inverseProportion: 1 / proportion,
    importance,
  };
};

const buildPokemonData = ([name, size, ...values]) => ({
  name,
  jab: {
    total: buildClusterData(size, ...values.slice(0, 7), size, buildVectorDataJab),
    clusters: [
      buildClusterData(...values.slice(7, 15), size, buildVectorDataJab),
      buildClusterData(...values.slice(15, 23), size, buildVectorDataJab),
      buildClusterData(...values.slice(23, 31), size, buildVectorDataJab),
      buildClusterData(...values.slice(31, 39), size, buildVectorDataJab),
    ].filter(c => c.size !== 0),
  },
  rgb: {
    total: buildClusterData(size, ...values.slice(39, 46), size, buildVectorDataRgb),
    clusters: [
      buildClusterData(...values.slice(46, 54), size, buildVectorDataRgb),
      buildClusterData(...values.slice(54, 62), size, buildVectorDataRgb),
      buildClusterData(...values.slice(62, 70), size, buildVectorDataRgb),
      buildClusterData(...values.slice(70, 78), size, buildVectorDataRgb),
    ].filter(c => c.size !== 0),
  },
});

const pokemonData = databaseV3.map(row => buildPokemonData(row));

const calcScores = (data, target) => {
  const sigma = Math.sqrt(
    data.inertia - 2 * vectorDot(data.mu.vector, target.vector) + target.sqMag
  );
  const bigTheta = 1 - vectorDot(data.nu, target.unit);
  const rawPhi = Math.abs(data.mu.hue - target.hue);
  return {
    sigma,
    bigTheta,
    alpha: sigma * Math.pow(bigTheta, target.chroma + target.lightness),

    theta: rad2deg * Math.acos(vectorDot(data.mu.unit, target.unit)),
    phi: Math.min(rawPhi, 360 - rawPhi),
    delta: vectorMag(data.mu.vector.map((x, i) => x - target.vector[i])),
    manhattan: data.mu.vector
      .map((x, i) => Math.abs(x - target.vector[i]))
      .reduce((x, y) => x + y),
    ch: Math.max(...data.mu.vector.map((x, i) => Math.abs(x - target.vector[i]))),
    lightnessDiff: Math.abs(data.mu.lightness - target.lightness),

    inertia: data.inertia,
    variance: data.inertia - data.mu.sqMag,
    muNuAngle: data.muNuAngle,
    size: data.size,
    lightness: data.mu.lightness,
    chroma: data.mu.chroma,
    importance: data.importance,

    inverseSize: data.inverseSize,
    proportion: data.proportion,
    inverseProportion: data.inverseProportion,

    muHex: data.mu.hex,
  };
};

const sortOrders = {
  max: (a, b) => b - a,
  min: (a, b) => a - b,
};

// ---- Styling ----

const rootStyle = document.querySelector(":root").style;

const setColorStyles = (style, hex) => {
  const highlight = getContrastingTextColor(hex);
  style.setProperty("--highlight", highlight);
  style.setProperty("--background", hex);
  style.setProperty("--shadow-component", highlight.includes("light") ? "255" : "0");
};

// ---- Pokemon Display ----

// pulled out bc the render uses them
const metricScores = {};
const bestClusterIndices = {};
const objectiveValues = {};

const pokemonTileTemplate = document.getElementById("pkmn-tile-template").content;
const pokemonDataTemplate = document.getElementById("pkmn-data-template").content;

const loadTemplateWithBinds = content => {
  const fragment = content.cloneNode(true);
  const binds = Object.fromEntries(
    Array.from(fragment.querySelectorAll("[bind-to]")).map(element => {
      const name = element.getAttribute("bind-to");
      element.removeAttribute("bind-to");
      return [name, element];
    })
  );
  return [fragment, binds];
};

const getSpriteName = (() => {
  const stripForm = [
    "flabebe",
    "floette",
    "florges",
    "vivillon",
    "basculin",
    "furfrou",
    "magearna",
    "alcremie",
  ];
  return pokemon => {
    pokemon = pokemon
      .replace("-alola", "-alolan")
      .replace("-galar", "-galarian")
      .replace("-hisui", "-hisuian")
      .replace("-paldea", "-paldean")
      .replace("-paldeanfire", "-paldean-fire") // tauros
      .replace("-paldeanwater", "-paldean-water") // tauros
      .replace("-phony", "") // sinistea and polteageist
      .replace("darmanitan-galarian", "darmanitan-galarian-standard")
      .replace("chienpao", "chien-pao")
      .replace("tinglu", "ting-lu")
      .replace("wochien", "wo-chien")
      .replace("chiyu", "chi-yu");
    if (stripForm.find(s => pokemon.includes(s))) {
      pokemon = pokemon.replace(/-.*$/, "");
    }
    return pokemon;
  };
})();

const formatName = name =>
  name
    .split("-")
    .map(part => part.charAt(0).toUpperCase() + part.substr(1))
    .join(" ");

const renderPokemon = (list, target) => {
  target.innerText = "";

  const {
    sortUseWholeImage,
    sortUseBestCluster,
    sortUseClusterSize,
    sortUseInvClusterSize,
    sortUseTotalSize,
    sortUseInvTotalSize,
  } = Object.fromEntries(new FormData(document.forms.colorCalculateForm).entries());

  const enableTotalFlags = !!(
    sortUseWholeImage ||
    sortUseTotalSize ||
    sortUseInvTotalSize
  );
  const enableClusterFlags = !!(
    sortUseBestCluster ||
    sortUseClusterSize ||
    sortUseInvClusterSize
  );

  list.forEach(pkmnName => {
    const [tile, { image, name, score, ...binds }] =
      loadTemplateWithBinds(pokemonTileTemplate);

    const spriteName = getSpriteName(pkmnName);
    const imageErrHandler = () => {
      image.removeEventListener("error", imageErrHandler);
      image.src = `https://img.pokemondb.net/sprites/scarlet-violet/icon/${spriteName}.png`;
    };
    image.addEventListener("error", imageErrHandler);
    image.src = `https://img.pokemondb.net/sprites/sword-shield/icon/${spriteName}.png`;

    name.innerText = name.title = image.alt = formatName(pkmnName);

    const colorSpace = document.forms.colorSortForm.elements.colorSpace.value;

    score.innerText = objectiveValues[pkmnName][colorSpace].toFixed(2);

    const { total, clusters } = metricScores[pkmnName][colorSpace];
    [
      [clusters[0], binds.cls1Btn, binds.cls1Data],
      [clusters[1], binds.cls2Btn, binds.cls2Data],
      [clusters[2], binds.cls3Btn, binds.cls3Data],
      [clusters[3], binds.cls4Btn, binds.cls4Data],
      [total, binds.totalBtn, binds.totalData],
    ]
      .filter(([data]) => !!data)
      .forEach(([data, button, dataTile], index) => {
        button.hidden = false;
        button.innerText = data.muHex;
        button.dataset.included =
          enableClusterFlags && index === bestClusterIndices[pkmnName][colorSpace];
        setColorStyles(button.style, data.muHex);
        button.addEventListener("click", () => {
          model.setTargetColor(data.muHex);
        });

        const [tooltip, tooltipBinds] = loadTemplateWithBinds(pokemonDataTemplate);
        Object.entries(tooltipBinds).forEach(([metricName, target]) => {
          target.innerText = data[metricName].toFixed(2).replace(".00", "");
        });

        dataTile.append(tooltip);
      });

    binds.totalBtn.dataset.included = enableTotalFlags;

    target.append(tile);
  });
};

const colorSearchResultsTarget = document.getElementById("color-results");
const nameSearchResultsTarget = document.getElementById("name-results");

// ---- Name Lookup ----

const lookupLimit = 24;
const pokemonLookup = new Fuse(pokemonData, { keys: ["name"] });
const nameSearchResults = [];

const renderNameSearchResults = () => {
  renderPokemon(nameSearchResults, nameSearchResultsTarget);
};

document.forms.nameSearchForm.elements.input.addEventListener(
  "input",
  ({ target: { value } }) => {
    nameSearchResults.splice(
      0,
      Infinity,
      ...pokemonLookup
        .search(value, { limit: lookupLimit })
        .map(({ item: { name } }) => name)
    );
    renderNameSearchResults();
  }
);

document.forms.nameSearchForm.elements.clear.addEventListener("click", () => {
  nameSearchResults.splice(0);
  document.forms.nameSearchForm.elements.input.value = "";
  renderNameSearchResults();
});

document.forms.nameSearchForm.elements.random.addEventListener("click", () => {
  nameSearchResults.splice(
    0,
    Infinity,
    ...Array.from(
      { length: lookupLimit },
      () => pokemonData[Math.floor(Math.random() * pokemonData.length)].name
    )
  );
  renderNameSearchResults();
});

// ---- Calculation Logic ----

const model = new (class {
  #targetColor = "";

  ranked = [];

  setTargetColor(newColor) {
    const hex = `#${newColor?.replace("#", "")}`;
    if (hex.length !== 7) {
      return;
    }

    setColorStyles(rootStyle, hex);

    const oldColor = this.#targetColor;
    this.#targetColor = hex;

    document.forms.targetColorForm.elements.colorText.value = hex;
    document.forms.targetColorForm.elements.colorText.dataset.lastValid = hex;
    document.forms.targetColorForm.elements.colorPicker.value = hex;

    if (oldColor) {
      const prevButton = document.createElement("button");
      prevButton.innerText = oldColor;
      prevButton.classList = "color-select";
      setColorStyles(prevButton.style, oldColor);
      prevButton.addEventListener("click", () => this.setTargetColor(oldColor));
      document.getElementById("prevColors").prepend(prevButton);
    }

    const rgb = d3.rgb(hex);
    const { J, a, b } = d3.jab(rgb);
    const targetJab = buildVectorDataJab([J, a, b]);
    const targetRgb = buildVectorDataRgb([rgb.r, rgb.g, rgb.b]);

    pokemonData.forEach(({ name, jab, rgb }) => {
      metricScores[name] = {
        jab: {
          total: calcScores(jab.total, targetJab),
          clusters: jab.clusters.map(c => calcScores(c, targetJab)),
        },
        rgb: {
          total: calcScores(rgb.total, targetRgb),
          clusters: rgb.clusters.map(c => calcScores(c, targetRgb)),
        },
      };
    });

    this.calculateObjective();
  }

  calculateObjective() {
    const {
      clusterUseClusterSize,
      clusterUseInvClusterSize,
      clusterUseTotalSize,
      clusterUseInvTotalSize,
      clusterSortOrder,
      sortUseWholeImage,
      sortUseBestCluster,
      sortUseClusterSize,
      sortUseInvClusterSize,
      sortUseTotalSize,
      sortUseInvTotalSize,
    } = Object.fromEntries(new FormData(document.forms.colorCalculateForm).entries());

    const clsMetric = document.forms.clusterMetricForm.elements.metric.value;
    const getClusterScore = productLift(
      cluster => cluster[clsMetric],
      clusterUseClusterSize && (cluster => cluster.size),
      clusterUseInvClusterSize && (cluster => cluster.inverseSize),
      clusterUseTotalSize && ((_, total) => total.size),
      clusterUseInvTotalSize && ((_, total) => total.inverseSize)
    );

    const clsSort = sortOrders[clusterSortOrder];
    const getBestClusterIndex = ({ total, clusters }) =>
      clusters
        .map((c, i) => [getClusterScore(c, total), i])
        .reduce((a, b) => (clsSort(a[0], b[0]) > 0 ? b : a))[1];

    Object.entries(metricScores).forEach(([name, { jab, rgb }]) => {
      bestClusterIndices[name] = {
        jab: getBestClusterIndex(jab),
        rgb: getBestClusterIndex(rgb),
      };
    });

    const metric = document.forms.sortMetricForm.elements.metric.value;
    const getSortScore = productLift(
      sortUseWholeImage && (({ total }) => total[metric]),
      sortUseBestCluster && (({ clusters }, i) => clusters[i][metric]),
      sortUseClusterSize && (({ clusters }, i) => clusters[i].size),
      sortUseInvClusterSize && (({ clusters }, i) => clusters[i].inverseSize),
      sortUseTotalSize && (({ total }) => total.size),
      sortUseInvTotalSize && (({ total }) => total.inverseSize)
    );

    Object.entries(metricScores).forEach(([name, { jab, rgb }]) => {
      objectiveValues[name] = {
        jab: getSortScore(jab, bestClusterIndices[name].jab),
        rgb: getSortScore(rgb, bestClusterIndices[name].rgb),
      };
    });

    renderNameSearchResults();
    this.rank();
  }

  rank() {
    const { colorSpace, sortOrder } = Object.fromEntries(
      new FormData(document.forms.colorSortForm).entries()
    );
    const compare = sortOrders[sortOrder];
    const sortFn = (a, b) =>
      compare(objectiveValues[a][colorSpace], objectiveValues[b][colorSpace]);

    this.ranked = pokemonData
      .map(({ name }) => name)
      .sort((a, b) => sortFn(a, b) || a.localeCompare(b));

    this.renderColorSearchResults();
  }

  renderColorSearchResults() {
    renderPokemon(
      this.ranked.slice(
        0,
        parseInt(document.forms.colorDisplayForm.elements.resultsToDisplay.value)
      ),
      colorSearchResultsTarget
    );
  }
})();

// ---- Form Controls ----

document.forms.targetColorForm.elements.colorText.addEventListener(
  "input",
  ({ target }) => {
    if (target.willValidate && !target.validity.valid) {
      target.value = target.dataset.lastValid || "";
    } else {
      model.setTargetColor(target.value);
    }
  }
);

document.forms.targetColorForm.elements.colorPicker.addEventListener(
  "change",
  ({ target }) => model.setTargetColor(target.value)
);

const randomizeTargetColor = () =>
  model.setTargetColor(
    d3.hsl(Math.random() * 360, Math.random(), Math.random()).formatHex()
  );

document.forms.targetColorForm.elements.randomColor.addEventListener(
  "click",
  randomizeTargetColor
);

document.forms.colorDisplayForm.elements.resultsToDisplay.addEventListener(
  "input",
  ({ target: { value } }) => {
    document.forms.colorDisplayForm.elements.output.value = value;
  }
);

document.forms.colorDisplayForm.elements.resultsToDisplay.addEventListener("change", () =>
  model.renderColorSearchResults()
);

Array.from(document.forms.colorSortForm.elements).forEach(el =>
  el.addEventListener("change", () => model.rank())
);

const clusterRankingTitle = document.getElementById("cls-title");
const clusterMetricSection = document.getElementById("cls-metric-mount");
const clusterFunctionSection = document.getElementById("cls-fn");

Array.from(document.forms.colorCalculateForm.elements).forEach(el =>
  el.addEventListener("change", () => {
    const { sortUseBestCluster, sortUseClusterSize, sortUseInvClusterSize } =
      Object.fromEntries(new FormData(document.forms.colorCalculateForm).entries());
    clusterRankingTitle.dataset.faded =
      clusterMetricSection.dataset.faded =
      clusterFunctionSection.dataset.faded =
        !(sortUseBestCluster || sortUseClusterSize || sortUseInvClusterSize);
    model.calculateObjective();
  })
);

// ---- Add Metric Selections ----

const metricSelectTemplate = document.getElementById("metric-select-template").content;
const sortMetricForm = metricSelectTemplate.cloneNode(true).firstElementChild;
sortMetricForm.id = "sortMetricForm";
const clusterMetricForm = metricSelectTemplate.cloneNode(true).firstElementChild;
clusterMetricForm.id = "clusterMetricForm";
document.getElementById("sort-metric-mount").append(sortMetricForm);
document.getElementById("cls-metric-mount").append(clusterMetricForm);

document.forms.sortMetricForm.elements.metricKind.value = "whole";
document.forms.clusterMetricForm.elements.metricKind.value = "stat";

const updateMetricSelects = form => {
  const kind = form.elements.metricKind.value;
  form.elements.whole.disabled = kind !== "whole";
  form.elements.mean.disabled = kind !== "mean";
  form.elements.stat.disabled = kind !== "stat";
  form.elements.metric.value = form.elements[kind].value;
};

const getMetricSymbol = metricName =>
  // terrible hack
  document.querySelector(`option[value=${metricName}]`).textContent.at(-2);

const onMetricChange = () => {
  updateMetricSelects(document.forms.sortMetricForm);
  updateMetricSelects(document.forms.clusterMetricForm);

  document.forms.colorCalculateForm.elements.sortMetricSymbolP.value =
    document.forms.colorCalculateForm.elements.sortMetricSymbolB.value = getMetricSymbol(
      document.forms.sortMetricForm.elements[
        document.forms.sortMetricForm.elements.metricKind.value
      ].value
    );

  document.forms.colorCalculateForm.elements.clusterMetricSymbol.value = getMetricSymbol(
    document.forms.clusterMetricForm.elements[
      document.forms.clusterMetricForm.elements.metricKind.value
    ].value
  );
};

onMetricChange();

document.forms.sortMetricForm.addEventListener("change", () => {
  onMetricChange();
  model.calculateObjective();
});

document.forms.clusterMetricForm.addEventListener("change", () => {
  onMetricChange();
  model.calculateObjective();
});

// ---- Pick Starting Color ----

randomizeTargetColor();