'use client'

import { useMemo } from 'react'
import { PieChart, Pie, Cell, ResponsiveContainer, Tooltip, Legend } from 'recharts'
import { useTheme } from '@/hooks/useTheme'
import { getChartPalette, getTooltipStyle, getTooltipItemStyle, getTooltipLabelStyle } from '../utils/chartTheme'
import { ChartCard } from './ChartCard'

interface ChainDecisionsPieProps {
  data: { decisionType: string; count: number }[] | undefined
  isLoading: boolean
}

function formatType(t: string): string {
  return t.replace(/_/g, ' ').replace(/\b\w/g, c => c.toUpperCase())
}

export function ChainDecisionsPie({ data, isLoading }: ChainDecisionsPieProps) {
  const { theme } = useTheme()
  const palette = useMemo(() => getChartPalette(), [theme])
  const tooltipStyle = useMemo(() => getTooltipStyle(), [theme])
  const tooltipItemStyle = useMemo(() => getTooltipItemStyle(), [theme])
  const tooltipLabelStyle = useMemo(() => getTooltipLabelStyle(), [theme])

  const chartData = useMemo(() => {
    if (!data?.length) return []
    return data.map(d => ({ name: formatType(d.decisionType), count: d.count }))
  }, [data])

  const total = chartData.reduce((s, d) => s + d.count, 0)

  return (
    <ChartCard title="Strategic Decisions" subtitle={`${total} decisions`} isLoading={isLoading} isEmpty={total === 0}>
      <ResponsiveContainer width="100%" height={220}>
        <PieChart>
          <Pie
            data={chartData}
            dataKey="count"
            nameKey="name"
            cx="50%"
            cy="50%"
            innerRadius={50}
            outerRadius={80}
            paddingAngle={2}
            stroke="none"
          >
            {chartData.map((_, i) => (
              <Cell key={i} fill={palette[i % palette.length]} />
            ))}
          </Pie>
          <Tooltip contentStyle={tooltipStyle} itemStyle={tooltipItemStyle} labelStyle={tooltipLabelStyle} />
          <Legend formatter={(value: string) => <span style={{ fontSize: 11 }}>{value}</span>} />
        </PieChart>
      </ResponsiveContainer>
    </ChartCard>
  )
}