NextEdu/src/modules/grades/components/grade-trend-chart.tsx

"use client"

import { BarChart3 } from "lucide-react"
import { CartesianGrid, Line, LineChart, XAxis, YAxis } from "recharts"

import {
  Card,
  CardContent,
  CardDescription,
  CardHeader,
  CardTitle,
} from "@/shared/components/ui/card"
import {
  ChartContainer,
  ChartTooltip,
  ChartTooltipContent,
} from "@/shared/components/ui/chart"
import { EmptyState } from "@/shared/components/ui/empty-state"
import { formatDate } from "@/shared/lib/utils"
import type { GradeTrendResult } from "@/modules/grades/types"

const chartConfig = {
  normalizedScore: {
    label: "Score (%)",
    color: "hsl(var(--primary))",
  },
}

interface GradeTrendChartProps {
  data: GradeTrendResult | null
}

export function GradeTrendChart({ data }: GradeTrendChartProps) {
  if (!data || data.points.length === 0) {
    return (
      <Card>
        <CardHeader>
          <CardTitle className="flex items-center gap-2">
            <BarChart3 className="h-4 w-4" />
            Grade Trend
          </CardTitle>
          <CardDescription>
            Score progression over time (normalized to 0-100).
          </CardDescription>
        </CardHeader>
        <CardContent>
          <EmptyState
            icon={BarChart3}
            title="No trend data"
            description="Select a class and subject to view the grade trend."
            className="border-none h-60"
          />
        </CardContent>
      </Card>
    )
  }

  const chartData = data.points.map((p) => ({
    title: p.title,
    normalizedScore: p.normalizedScore,
    fullTitle: p.title,
    date: formatDate(p.date),
    rawScore: p.score,
    fullScore: p.fullScore,
    type: p.type,
  }))

  return (
    <Card>
      <CardHeader>
        <CardTitle className="flex items-center gap-2">
          <BarChart3 className="h-4 w-4" />
          Grade Trend
        </CardTitle>
        <CardDescription>
          {data.label} · avg {data.averageScore.toFixed(1)}%
        </CardDescription>
      </CardHeader>
      <CardContent>
        <ChartContainer config={chartConfig} className="h-[280px] w-full">
          <LineChart
            data={chartData}
            margin={{ left: 8, right: 8, top: 8, bottom: 8 }}
          >
            <CartesianGrid
              vertical={false}
              strokeDasharray="4 4"
              strokeOpacity={0.4}
            />
            <XAxis
              dataKey="title"
              tickLine={false}
              axisLine={false}
              tickMargin={8}
              tickFormatter={(value: string) =>
                value.length > 10 ? `${value.slice(0, 10)}...` : value
              }
            />
            <YAxis
              domain={[0, 100]}
              tickLine={false}
              axisLine={false}
              tickFormatter={(value: number) => `${value}%`}
              width={36}
            />
            <ChartTooltip
              cursor={{
                stroke: "hsl(var(--muted-foreground))",
                strokeWidth: 1,
                strokeDasharray: "4 4",
              }}
              content={
                <ChartTooltipContent
                  indicator="line"
                  labelKey="fullTitle"
                  className="w-[220px]"
                />
              }
            />
            <Line
              dataKey="normalizedScore"
              type="monotone"
              stroke="var(--color-normalizedScore)"
              strokeWidth={2}
              dot={{
                fill: "var(--color-normalizedScore)",
                r: 3,
                strokeWidth: 2,
              }}
              activeDot={{ r: 5, strokeWidth: 0 }}
            />
          </LineChart>
        </ChartContainer>
      </CardContent>
    </Card>
  )
}