From c25822dee07b6f0fcf117c1816126821376e0d58 Mon Sep 17 00:00:00 2001
From: AmanTahiliani <amantahiliani7437@gmail.com>
Date: Mon, 25 May 2026 13:20:55 -0400
Subject: [PATCH] Phase 22b: Interactive Race Story Canvas

---
 frontend/src/components/RaceStoryCanvas.tsx | 175 ++++++++++++++++++--
 frontend/src/styles/app.css                 |  33 ++++
 2 files changed, 196 insertions(+), 12 deletions(-)

diff --git a/frontend/src/components/RaceStoryCanvas.tsx b/frontend/src/components/RaceStoryCanvas.tsx
index e40ba23..8fd940a 100644
--- a/frontend/src/components/RaceStoryCanvas.tsx
+++ b/frontend/src/components/RaceStoryCanvas.tsx
@@ -1,3 +1,4 @@
+import { useState, useMemo, useRef, useCallback } from 'react'
 import type { EnrichedResult, EnrichedGrid, PositionSample, Lap } from '../types'
 import { gridDelta, gridDeltaClass, formatDuration, formatGap } from '../utils'
 
@@ -8,18 +9,26 @@ interface Props {
     positions: PositionSample[]
     laps: Lap[]
     datasets: Record<string, any>
+    race_control?: any[]
+    pit_stops?: any[]
   }
 }
 
 export function RaceStoryCanvas({ data }: Props) {
-  const { results, starting_grid: grid, positions, datasets } = data
+  const { results, starting_grid: grid, positions, datasets, race_control = [], pit_stops = [] } = data
   const hasPositions = datasets['positions']?.status === 'available'
 
+  const [scrubTime, setScrubTime] = useState<number | null>(null)
+  const [hoverDriver, setHoverDriver] = useState<number | null>(null)
+  const svgRef = useRef<SVGSVGElement>(null)
+
   // Position Evolution Chart Logic
-  const allTimes = [...new Set(positions.map((p) => p.date))].sort()
+  const allTimes = useMemo(() => [...new Set(positions.map((p) => p.date))].sort(), [positions])
   const hasChartData = hasPositions && allTimes.length > 0
 
   let chartContent = null
+  let displayResults = results
+
   if (hasChartData) {
     const tMin = new Date(allTimes[0]).getTime()
     const tMax = new Date(allTimes[allTimes.length - 1]).getTime()
@@ -37,6 +46,36 @@ export function RaceStoryCanvas({ data }: Props) {
       samples.sort((a, b) => a.t - b.t)
     }
 
+    const getInterpPos = (samples: {t: number, pos: number}[], t: number) => {
+      if (!samples || samples.length === 0) return null
+      if (t <= samples[0].t) return samples[0].pos
+      if (t >= samples[samples.length - 1].t) return samples[samples.length - 1].pos
+      for (let i = 0; i < samples.length - 1; i++) {
+        if (samples[i].t <= t && samples[i+1].t >= t) {
+          const dt = samples[i+1].t - samples[i].t
+          if (dt === 0) return samples[i].pos
+          const frac = (t - samples[i].t) / dt
+          return samples[i].pos + (samples[i+1].pos - samples[i].pos) * frac
+        }
+      }
+      return null
+    }
+
+    if (scrubTime !== null) {
+      const currentPos = new Map<number, number>()
+      for (const [dNum, samples] of byDriver.entries()) {
+        const pos = getInterpPos(samples, scrubTime)
+        if (pos !== null) {
+          currentPos.set(dNum, pos)
+        }
+      }
+      displayResults = [...results].sort((a, b) => {
+        const posA = currentPos.get(a.driver_number) ?? 999
+        const posB = currentPos.get(b.driver_number) ?? 999
+        return posA - posB
+      })
+    }
+
     const maxPos = Math.max(...positions.map((p) => p.position), results.length, 2)
     const colorByDriver = new Map(results.map((r) => [r.driver_number, r.team_colour]))
     const acronymByDriver = new Map(results.map((r) => [r.driver_number, r.name_acronym]))
@@ -53,14 +92,66 @@ export function RaceStoryCanvas({ data }: Props) {
     const toX = (t: number) => PL + t * plotW
     const toY = (pos: number) => PT + ((pos - 1) / Math.max(maxPos - 1, 1)) * plotH
 
+    // Safety Car / VSC periods
+    const scPeriods: { start: number; end: number | null; type: 'SC' | 'VSC' }[] = []
+    let activeSC: { start: number; type: 'SC' | 'VSC' } | null = null
+    const rc = [...race_control].sort((a, b) => new Date(a.date).getTime() - new Date(b.date).getTime())
+    
+    for (const msg of rc) {
+      const t = new Date(msg.date).getTime()
+      const m = msg.message?.toUpperCase() || ''
+      const cat = msg.category?.toUpperCase() || ''
+      
+      if (m.includes('VIRTUAL SAFETY CAR DEPLOYED') || cat === 'VIRTUALSAFETYCAR') {
+        if (!activeSC) activeSC = { start: t, type: 'VSC' }
+      } else if (m.includes('SAFETY CAR DEPLOYED') || cat === 'SAFETYCAR') {
+        if (!activeSC) activeSC = { start: t, type: 'SC' }
+      } else if (m.includes('TRACK CLEAR') || m.includes('CLEAR')) {
+        if (activeSC) {
+          scPeriods.push({ start: activeSC.start, end: t, type: activeSC.type })
+          activeSC = null
+        }
+      }
+    }
+    if (activeSC) {
+      scPeriods.push({ start: activeSC.start, end: null, type: activeSC.type })
+    }
+
+    const handlePointerMove = (e: React.PointerEvent<SVGRectElement>) => {
+      if (!svgRef.current) return
+      const rect = svgRef.current.getBoundingClientRect()
+      const x = e.clientX - rect.left
+      const t = Math.max(0, Math.min(1, (x - PL) / plotW))
+      setScrubTime(t)
+    }
+
     chartContent = (
       <div className="rs-chart-container scroll-x" data-testid="position-chart">
         <svg
+          ref={svgRef}
           viewBox={`0 0 ${W} ${H}`}
           style={{ width: '100%', minWidth: 280, maxWidth: W, display: 'block' }}
           role="img"
           aria-label="Position evolution chart"
         >
+          {scPeriods.map((sc, i) => {
+            const startT = (sc.start - tMin) / tRange
+            const endT = sc.end ? (sc.end - tMin) / tRange : 1
+            const x1 = toX(Math.max(0, startT))
+            const x2 = toX(Math.min(1, endT))
+            if (x2 <= PL || x1 >= W - PR) return null
+            return (
+              <rect
+                key={`sc-${i}`}
+                x={x1}
+                y={PT}
+                width={Math.max(0, x2 - x1)}
+                height={plotH}
+                fill={sc.type === 'SC' ? 'rgba(255, 153, 0, 0.15)' : 'rgba(255, 204, 0, 0.1)'}
+              />
+            )
+          })}
+
           {Array.from({ length: maxPos }, (_, i) => i + 1).map((pos) => (
             <g key={pos}>
               <line
@@ -89,28 +180,56 @@ export function RaceStoryCanvas({ data }: Props) {
             const color = colour ? `#${colour}` : '#888'
             const pts = samples.map((s) => `${toX(s.t)},${toY(s.pos)}`).join(' ')
             const last = samples[samples.length - 1]
+            const isHovered = hoverDriver === dNum
+            const isFaded = hoverDriver !== null && !isHovered
+
+            const driverPits = pit_stops.filter(p => p.driver_number === dNum)
 
             return (
-              <g key={dNum}>
+              <g 
+                key={dNum}
+                style={{ opacity: isFaded ? 0.2 : 1, transition: 'opacity 0.2s' }}
+                onMouseEnter={() => setHoverDriver(dNum)}
+                onMouseLeave={() => setHoverDriver(null)}
+              >
                 <polyline
                   points={pts}
                   fill="none"
                   stroke={color}
-                  strokeWidth={2}
+                  strokeWidth={isHovered ? 3 : 2}
                   strokeLinejoin="round"
                   strokeLinecap="round"
+                  className="rs-driver-line"
                 />
-                {samples.map((s, i) => (
-                  <circle key={i} cx={toX(s.t)} cy={toY(s.pos)} r={3} fill={color} />
-                ))}
+                
+                {driverPits.map((p, i) => {
+                  const t = (new Date(p.date).getTime() - tMin) / tRange
+                  if (t < 0 || t > 1) return null
+                  const pos = getInterpPos(samples, t)
+                  if (pos === null) return null
+                  return (
+                    <circle 
+                      key={`pit-${i}`} 
+                      cx={toX(t)} 
+                      cy={toY(pos)} 
+                      r={3} 
+                      fill="var(--bg)" 
+                      stroke={color} 
+                      strokeWidth={2}
+                      className="rs-pit-dot"
+                    />
+                  )
+                })}
+                
                 {last && (
                   <text
                     x={toX(last.t) + 6}
                     y={toY(last.pos) + 4}
                     fill={color}
-                    fontSize={9}
+                    fontSize={isHovered ? 11 : 9}
                     fontFamily="var(--f-mono)"
                     fontWeight={700}
+                    style={{ cursor: 'default' }}
                   >
                     {acronymByDriver.get(dNum) ?? dNum}
                   </text>
@@ -118,6 +237,31 @@ export function RaceStoryCanvas({ data }: Props) {
               </g>
             )
           })}
+
+          {scrubTime !== null && (
+            <line
+              x1={toX(scrubTime)}
+              x2={toX(scrubTime)}
+              y1={PT}
+              y2={H - PB}
+              stroke="var(--text)"
+              strokeWidth={1}
+              strokeDasharray="4 2"
+              className="rs-playhead"
+              style={{ pointerEvents: 'none' }}
+            />
+          )}
+
+          <rect
+            x={PL}
+            y={PT}
+            width={plotW}
+            height={plotH}
+            fill="transparent"
+            onPointerMove={handlePointerMove}
+            onPointerLeave={() => setScrubTime(null)}
+            style={{ cursor: 'crosshair', touchAction: 'none' }}
+          />
         </svg>
       </div>
     )
@@ -134,17 +278,24 @@ export function RaceStoryCanvas({ data }: Props) {
         </div>
       )}
 
-      {results.length > 0 && (
+      {displayResults.length > 0 && (
         <div className="rs-field-list">
-          {results.map((r, i) => {
+          {displayResults.map((r, i) => {
             const gridPos = grid.find((g) => g.driver_number === r.driver_number)?.position ?? 0
             const isWinner = i === 0 && r.position === 1
             const pClass = r.position === 1 ? 'rs-pos-p1' : r.position === 2 ? 'rs-pos-p2' : r.position === 3 ? 'rs-pos-p3' : ''
             
             return (
-              <div key={r.driver_number} className="rs-driver-row">
+              <div 
+                key={r.driver_number} 
+                className={`rs-driver-row ${hoverDriver === r.driver_number ? 'rs-driver-row-hover' : ''}`}
+                onMouseEnter={() => setHoverDriver(r.driver_number)}
+                onMouseLeave={() => setHoverDriver(null)}
+              >
                 <div className="rs-driver-left">
-                  <div className={`rs-pos-col ${pClass}`}>{r.position}</div>
+                  <div className={`rs-pos-col ${pClass}`}>
+                    {scrubTime !== null ? i + 1 : r.position}
+                  </div>
                   <div className="rs-driver-cell">
                     <div 
                       className="rs-driver-color" 
diff --git a/frontend/src/styles/app.css b/frontend/src/styles/app.css
index 06cbea8..9de2761 100644
--- a/frontend/src/styles/app.css
+++ b/frontend/src/styles/app.css
@@ -2498,3 +2498,36 @@ a { color: inherit; text-decoration: none; }
     display: none;
   }
 }
+
+/* Interactive Race Story Canvas elements */
+.rs-driver-line {
+  stroke-dasharray: 4000;
+  stroke-dashoffset: 4000;
+  animation: drawLine 2.5s cubic-bezier(0.2, 0.8, 0.2, 1) forwards;
+}
+
+@keyframes drawLine {
+  to {
+    stroke-dashoffset: 0;
+  }
+}
+
+.rs-pit-dot {
+  opacity: 0;
+  animation: fadeIn 0.5s ease-in-out 1.5s forwards;
+}
+
+@keyframes fadeIn {
+  to {
+    opacity: 1;
+  }
+}
+
+.rs-playhead {
+  transition: x1 0.05s linear, x2 0.05s linear;
+}
+
+.rs-driver-row-hover {
+  background: var(--surface-h);
+  border-color: var(--border-2);
+}