From f63c775cb6060c97721a26074ffaa50434a34716 Mon Sep 17 00:00:00 2001
From: Ozzie Gooen <ozzieagooen@gmail.com>
Date: Thu, 7 Apr 2022 09:53:45 -0400
Subject: [PATCH] Simple implementation of function hover working

---
 packages/components/src/SquiggleChart.tsx     | 356 ++++++++++--------
 packages/components/src/spec-percentiles.json |  20 +-
 .../src/stories/SquiggleChart.stories.mdx     |   2 +-
 3 files changed, 224 insertions(+), 154 deletions(-)

diff --git a/packages/components/src/SquiggleChart.tsx b/packages/components/src/SquiggleChart.tsx
index e381127c..ce978706 100644
--- a/packages/components/src/SquiggleChart.tsx
+++ b/packages/components/src/SquiggleChart.tsx
@@ -13,6 +13,7 @@ import * as chartSpecification from "./spec-distributions.json";
 import * as percentilesSpec from "./spec-percentiles.json";
 import { NumberShower } from "./NumberShower";
 import styled from "styled-components";
+import { CONTINUOUS_TO_DISCRETE_SCALES } from "vega-lite/build/src/scale";
 
 let SquiggleVegaChart = createClassFromSpec({
   spec: chartSpecification as Spec,
@@ -65,6 +66,195 @@ const ShowError: React.FC<{ heading: string; children: React.ReactNode }> = ({
   );
 };
 
+export const DistPlusChart: React.FC<{
+  distPlus: DistPlus;
+  width: number;
+  height: number;
+}> = ({ distPlus, width, height }) => {
+  let shape = distPlus.pointSetDist;
+  if (shape.tag === "Continuous") {
+    let xyShape = shape.value.xyShape;
+    let totalY = xyShape.ys.reduce((a, b) => a + b);
+    let total = 0;
+    let cdf = xyShape.ys.map((y) => {
+      total += y;
+      return total / totalY;
+    });
+    let values = _.zip(cdf, xyShape.xs, xyShape.ys).map(([c, x, y]) => ({
+      cdf: (c * 100).toFixed(2) + "%",
+      x: x,
+      y: y,
+    }));
+
+    return (
+      <SquiggleVegaChart
+        width={width}
+        height={height}
+        data={{ con: values }}
+        actions={false}
+      />
+    );
+  } else if (shape.tag === "Discrete") {
+    let xyShape = shape.value.xyShape;
+    let totalY = xyShape.ys.reduce((a, b) => a + b);
+    let total = 0;
+    let cdf = xyShape.ys.map((y) => {
+      total += y;
+      return total / totalY;
+    });
+    let values = _.zip(cdf, xyShape.xs, xyShape.ys).map(([c, x, y]) => ({
+      cdf: (c * 100).toFixed(2) + "%",
+      x: x,
+      y: y,
+    }));
+
+    return <SquiggleVegaChart data={{ dis: values }} actions={false} />;
+  } else if (shape.tag === "Mixed") {
+    let discreteShape = shape.value.discrete.xyShape;
+    let totalDiscrete = discreteShape.ys.reduce((a, b) => a + b);
+
+    let discretePoints = _.zip(discreteShape.xs, discreteShape.ys);
+    let continuousShape = shape.value.continuous.xyShape;
+    let continuousPoints = _.zip(continuousShape.xs, continuousShape.ys);
+
+    interface labeledPoint {
+      x: number;
+      y: number;
+      type: "discrete" | "continuous";
+    }
+
+    let markedDisPoints: labeledPoint[] = discretePoints.map(([x, y]) => ({
+      x: x,
+      y: y,
+      type: "discrete",
+    }));
+    let markedConPoints: labeledPoint[] = continuousPoints.map(([x, y]) => ({
+      x: x,
+      y: y,
+      type: "continuous",
+    }));
+
+    let sortedPoints = _.sortBy(markedDisPoints.concat(markedConPoints), "x");
+
+    let totalContinuous = 1 - totalDiscrete;
+    let totalY = continuousShape.ys.reduce((a: number, b: number) => a + b);
+
+    let total = 0;
+    let cdf = sortedPoints.map((point: labeledPoint) => {
+      if (point.type === "discrete") {
+        total += point.y;
+        return total;
+      } else if (point.type === "continuous") {
+        total += (point.y / totalY) * totalContinuous;
+        return total;
+      }
+    });
+
+    interface cdfLabeledPoint {
+      cdf: string;
+      x: number;
+      y: number;
+      type: "discrete" | "continuous";
+    }
+    let cdfLabeledPoint: cdfLabeledPoint[] = _.zipWith(
+      cdf,
+      sortedPoints,
+      (c: number, point: labeledPoint) => ({
+        ...point,
+        cdf: (c * 100).toFixed(2) + "%",
+      })
+    );
+    let continuousValues = cdfLabeledPoint.filter(
+      (x) => x.type === "continuous"
+    );
+    let discreteValues = cdfLabeledPoint.filter((x) => x.type === "discrete");
+
+    return (
+      <SquiggleVegaChart
+        data={{ con: continuousValues, dis: discreteValues }}
+        actions={false}
+      />
+    );
+  }
+};
+
+const _rangeByCount = (start, stop, count) => {
+  const step = (stop - start) / (count - 1);
+  const items = _.range(start, stop, step);
+  const result = items.concat([stop]);
+  return result;
+};
+
+type distPlusFn = (
+  a: number
+) => { tag: "Ok"; value: DistPlus } | { tag: "Error"; value: string };
+
+// This could really use a line in the location of the signal. I couldn't get it to work.
+// https://vega.github.io/vega/docs/signals/#handlers
+
+export const FunctionChart: React.FC<{
+  distPlusFn: distPlusFn;
+  diagramStart: number;
+  diagramStop: number;
+  diagramCount: number;
+}> = ({ distPlusFn, diagramStart, diagramStop, diagramCount }) => {
+  let [mouseOverlay, setMouseOverlay] = React.useState(NaN);
+  function handleHover(...args) {
+    setMouseOverlay(args[1]);
+  }
+  function handleOut(...args) {
+    setMouseOverlay(NaN);
+  }
+  const signalListeners = { mousemove: handleHover, mouseout: handleOut };
+  let percentileArray = [
+    0.01, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 0.95, 0.99,
+  ];
+  let mouseItem = distPlusFn(mouseOverlay);
+  let showChart =
+    mouseItem.tag === "Ok" ? (
+      <DistPlusChart distPlus={mouseItem.value} width={400} height={140} />
+    ) : (
+      <></>
+    );
+  let data = _rangeByCount(diagramStart, diagramStop, diagramCount)
+    .map((x) => {
+      let result = distPlusFn(x);
+      if (result.tag === "Ok") {
+        let percentiles = getPercentiles(percentileArray, result.value);
+        return {
+          x: x,
+          p1: percentiles[0],
+          p5: percentiles[1],
+          p10: percentiles[2],
+          p20: percentiles[3],
+          p30: percentiles[4],
+          p40: percentiles[5],
+          p50: percentiles[6],
+          p60: percentiles[7],
+          p70: percentiles[8],
+          p80: percentiles[9],
+          p90: percentiles[10],
+          p95: percentiles[11],
+          p99: percentiles[12],
+        };
+      } else {
+        console.log("Error", x, result);
+        return null;
+      }
+    })
+    .filter((x) => x !== null);
+  return (
+    <>
+      <SquigglePercentilesChart
+        data={{ facet: data }}
+        actions={false}
+        signalListeners={signalListeners}
+      />
+      {showChart}
+    </>
+  );
+};
+
 export const SquiggleChart: React.FC<SquiggleChartProps> = ({
   squiggleString = "",
   sampleCount = 1000,
@@ -95,154 +285,20 @@ export const SquiggleChart: React.FC<SquiggleChartProps> = ({
       if (chartResult["NAME"] === "Float") {
         return <NumberShower precision={3} number={chartResult["VAL"]} />;
       } else if (chartResult["NAME"] === "DistPlus") {
-        let shape = chartResult.VAL.pointSetDist;
-        if (shape.tag === "Continuous") {
-          let xyShape = shape.value.xyShape;
-          let totalY = xyShape.ys.reduce((a, b) => a + b);
-          let total = 0;
-          let cdf = xyShape.ys.map((y) => {
-            total += y;
-            return total / totalY;
-          });
-          let values = _.zip(cdf, xyShape.xs, xyShape.ys).map(([c, x, y]) => ({
-            cdf: (c * 100).toFixed(2) + "%",
-            x: x,
-            y: y,
-          }));
-
-          return (
-            <SquiggleVegaChart
-              width={width}
-              height={height}
-              data={{ con: values }}
-              actions={false}
-            />
-          );
-        } else if (shape.tag === "Discrete") {
-          let xyShape = shape.value.xyShape;
-          let totalY = xyShape.ys.reduce((a, b) => a + b);
-          let total = 0;
-          let cdf = xyShape.ys.map((y) => {
-            total += y;
-            return total / totalY;
-          });
-          let values = _.zip(cdf, xyShape.xs, xyShape.ys).map(([c, x, y]) => ({
-            cdf: (c * 100).toFixed(2) + "%",
-            x: x,
-            y: y,
-          }));
-
-          return <SquiggleVegaChart data={{ dis: values }} actions={false} />;
-        } else if (shape.tag === "Mixed") {
-          let discreteShape = shape.value.discrete.xyShape;
-          let totalDiscrete = discreteShape.ys.reduce((a, b) => a + b);
-
-          let discretePoints = _.zip(discreteShape.xs, discreteShape.ys);
-          let continuousShape = shape.value.continuous.xyShape;
-          let continuousPoints = _.zip(continuousShape.xs, continuousShape.ys);
-
-          interface labeledPoint {
-            x: number;
-            y: number;
-            type: "discrete" | "continuous";
-          }
-
-          let markedDisPoints: labeledPoint[] = discretePoints.map(
-            ([x, y]) => ({ x: x, y: y, type: "discrete" })
-          );
-          let markedConPoints: labeledPoint[] = continuousPoints.map(
-            ([x, y]) => ({ x: x, y: y, type: "continuous" })
-          );
-
-          let sortedPoints = _.sortBy(
-            markedDisPoints.concat(markedConPoints),
-            "x"
-          );
-
-          let totalContinuous = 1 - totalDiscrete;
-          let totalY = continuousShape.ys.reduce(
-            (a: number, b: number) => a + b
-          );
-
-          let total = 0;
-          let cdf = sortedPoints.map((point: labeledPoint) => {
-            if (point.type === "discrete") {
-              total += point.y;
-              return total;
-            } else if (point.type === "continuous") {
-              total += (point.y / totalY) * totalContinuous;
-              return total;
-            }
-          });
-
-          interface cdfLabeledPoint {
-            cdf: string;
-            x: number;
-            y: number;
-            type: "discrete" | "continuous";
-          }
-          let cdfLabeledPoint: cdfLabeledPoint[] = _.zipWith(
-            cdf,
-            sortedPoints,
-            (c: number, point: labeledPoint) => ({
-              ...point,
-              cdf: (c * 100).toFixed(2) + "%",
-            })
-          );
-          let continuousValues = cdfLabeledPoint.filter(
-            (x) => x.type === "continuous"
-          );
-          let discreteValues = cdfLabeledPoint.filter(
-            (x) => x.type === "discrete"
-          );
-
-          return (
-            <SquiggleVegaChart
-              data={{ con: continuousValues, dis: discreteValues }}
-              actions={false}
-            />
-          );
-        }
-      } else if (chartResult.NAME === "Function") {
-        // We are looking at a function. In this case, we draw a Percentiles chart
-        let start = diagramStart;
-        let stop = diagramStop;
-        let count = diagramCount;
-        let step = (stop - start) / count;
-        let data = _.range(start, stop, step).map((x) => {
-          if (chartResult.NAME === "Function") {
-            let result = chartResult.VAL(x);
-            if (result.tag === "Ok") {
-              let percentileArray = [
-                0.01, 0.05, 0.1, 0.2, 0.3, 0.4, 0.5, 0.6, 0.7, 0.8, 0.9, 0.95,
-                0.99,
-              ];
-
-              let percentiles = getPercentiles(percentileArray, result.value);
-              return {
-                x: x,
-                p1: percentiles[0],
-                p5: percentiles[1],
-                p10: percentiles[2],
-                p20: percentiles[3],
-                p30: percentiles[4],
-                p40: percentiles[5],
-                p50: percentiles[6],
-                p60: percentiles[7],
-                p70: percentiles[8],
-                p80: percentiles[9],
-                p90: percentiles[10],
-                p95: percentiles[11],
-                p99: percentiles[12],
-              };
-            }
-            return null;
-          }
-        });
         return (
-          <SquigglePercentilesChart
-            data={{ facet: data.filter((x) => x !== null) }}
-            actions={false}
+          <DistPlusChart
+            distPlus={chartResult.VAL}
+            height={height}
+            width={width}
+          />
+        );
+      } else if (chartResult.NAME === "Function") {
+        return (
+          <FunctionChart
+            distPlusFn={chartResult.VAL}
+            diagramStart={diagramStart}
+            diagramStop={diagramStop}
+            diagramCount={diagramCount}
           />
         );
       }
@@ -250,11 +306,7 @@ export const SquiggleChart: React.FC<SquiggleChartProps> = ({
     return <>{chartResults}</>;
   } else if (result.tag === "Error") {
     // At this point, we came across an error. What was our error?
-    return (
-      <ShowError heading={"Parse Error"}>
-        {result.value}
-      </ShowError>
-    );
+    return <ShowError heading={"Parse Error"}>{result.value}</ShowError>;
   }
   return <p>{"Invalid Response"}</p>;
 };
diff --git a/packages/components/src/spec-percentiles.json b/packages/components/src/spec-percentiles.json
index 5751f924..a9fc08d4 100644
--- a/packages/components/src/spec-percentiles.json
+++ b/packages/components/src/spec-percentiles.json
@@ -1,7 +1,7 @@
 {
   "$schema": "https://vega.github.io/schema/vega/v5.json",
   "width": 500,
-  "height": 400,
+  "height": 200,
   "padding": 5,
   "data": [
     {
@@ -93,6 +93,16 @@
       }
     }
   ],
+  "signals": [
+    {
+      "name": "mousemove",
+      "on": [{"events": "mousemove", "update": "invert('xscale', x())"}]
+    },
+    {
+      "name": "mouseout",
+      "on": [{"events": "mouseout", "update": "invert('xscale', x())"}]
+    }
+  ],
   "axes": [
     {
       "orient": "bottom",
@@ -118,6 +128,14 @@
     }
   ],
   "marks": [
+    {
+      "type": "rule",
+      "encode": {
+        "update": {
+          "xscale": {"scale": "xscale", "signal": "mousemove"}
+        }
+      }
+    },
     {
       "type": "area",
       "from": {
diff --git a/packages/components/src/stories/SquiggleChart.stories.mdx b/packages/components/src/stories/SquiggleChart.stories.mdx
index 76c40228..94273232 100644
--- a/packages/components/src/stories/SquiggleChart.stories.mdx
+++ b/packages/components/src/stories/SquiggleChart.stories.mdx
@@ -83,7 +83,7 @@ The default is show 10 points between 0 and 10.
   <Story
     name="Function"
     args={{
-      squiggleString: "f(x) = normal(x^2,x^1.8)\nf",
+      squiggleString: "f(x) = normal(x^2,(x+.1)^1.8)\nf",
     }}
   >
     {Template.bind({})}