import {
  getCommonOptions,
  mergeEchartWidgetConfig,
  type EchartOptionsProps,
} from '../echart'
import type { BarConfig, BarWidgetConfig, BarWidgetData } from './types'
import {
  flattenObjectArrayToCSV,
  buildLegendConfig,
  buildGridConfig,
  createTooltipPositioner,
  createTooltipFormatter,
  createChartDownloadConfig,
  applyXAxisFormatter,
  niceNum,
  buildSeriesLabelConfig,
} from '../utils/chart-config'

export const barDownloadConfig = createChartDownloadConfig<BarWidgetData>(
  flattenObjectArrayToCSV,
)

/**
 * Generates ECharts configuration for bar chart widgets (vertical and horizontal), including axis, tooltip, legend, and series options styled with the CARTO theme.
 *
 * @param props - Bar chart configuration including data and theme.
 * @returns Widget config with ECharts option object.
 */
export function barConfig(props: BarConfig): BarWidgetConfig {
  return {
    type: 'bar',
    option: mergeEchartWidgetConfig(getCommonOptions(props), getOption(props)),
    formatter: props.formatter,
    labelFormatter: props.labelFormatter,
  }
}

function getOption({
  data = [],
  theme,
  formatter,
  labelFormatter,
}: BarConfig): EchartOptionsProps {
  const hasLegend = (data?.length ?? 0) > 1

  let niceMin = 0
  let niceMax = 1

  return {
    legend: buildLegendConfig({ hasLegend, labelFormatter }),
    grid: buildGridConfig(hasLegend, theme),
    xAxis: applyXAxisFormatter(
      {
        type: 'category',
        axisLine: {
          show: false,
        },
        axisTick: {
          show: false,
        },
        axisLabel: {
          padding: [parseInt(theme.spacing(0.5)), 0, 0, 0],
          margin: 0,
          showMinLabel: undefined,
          showMaxLabel: undefined,
          hideOverlap: true,
        },
      },
      labelFormatter,
    ),
    yAxis: {
      type: 'value' as const,
      min: (extent: { min: number }) => {
        niceMin = extent.min < 0 ? niceNum(extent.min) : 0
        return niceMin
      },
      max: (extent: { min: number; max: number }) => {
        niceMax = extent.max <= 0 ? 1 : niceNum(extent.max)
        return niceMax
      },
      axisLabel: {
        fontSize: theme.typography.overlineDelicate.fontSize,
        fontFamily: theme.typography.overlineDelicate.fontFamily,
        margin: parseInt(theme.spacing(1)),
        show: true,
        showMaxLabel: true,
        showMinLabel: true,
        verticalAlign: 'bottom' as const,
        inside: true,
        formatter: (value: number) => {
          if (value !== niceMax && value !== niceMin) return ''
          if (value === 0) return ''
          return formatter ? formatter(value) : String(value)
        },
      },
      axisLine: {
        show: false,
      },
      axisTick: {
        show: false,
      },
      splitLine: {
        show: true,
        lineStyle: {
          color: theme.palette.black[4],
        },
      },
    },
    tooltip: {
      position: createTooltipPositioner(theme),
      formatter: createTooltipFormatter((item) => {
        const value = item.value as Record<string, string | number>
        const index = item.dimensionNames?.[item.encode?.y?.at(0) ?? 1]
        const _value = value[index ?? '']

        const formattedValue =
          typeof _value === 'number' && formatter
            ? formatter(_value)
            : (_value ?? '')

        const marker = typeof item.marker === 'string' ? item.marker : ''
        const seriesName = item.seriesName ? `${item.seriesName}: ` : ''
        const name = labelFormatter
          ? String(labelFormatter(item.name ?? ''))
          : (item.name ?? '')

        return { name, seriesName, marker, value: formattedValue }
      }),
    },
    series: data.map((_: unknown, index: number) => ({
      datasetIndex: index,
      type: 'bar',
      barMaxWidth: 100,
      emphasis: {
        focus: 'series',
      },
      ...buildSeriesLabelConfig(formatter),
    })),
  } as EchartOptionsProps
}