import * as plotly from "plotly.js-dist-min"
import React, { FC, ReactNode, useEffect, useState } from "react"
import {
  Typography,
  useTheme,
  Box,
  Grid,
  FormGroup,
  FormControlLabel,
  Checkbox,
} from "@mui/material"
import { plotlyDarkTemplate } from "./PlotlyDarkMode"
import {
  Target,
  useFilteredTrials,
  useObjectiveAndUserAttrTargets,
  useParamTargets,
} from "../trialFilter"
import { useMergedUnionSearchSpace } from "../searchSpace"

const plotDomId = "graph-parallel-coordinate"

const useTargets = (
  study: StudyDetail | null
): [Target[], SearchSpaceItem[], () => ReactNode] => {
  const [targets1, _target1, _setter1] = useObjectiveAndUserAttrTargets(study)
  const searchSpace = useMergedUnionSearchSpace(study?.union_search_space)
  const [targets2, _target2, _setter2] = useParamTargets(searchSpace)
  const [checked, setChecked] = useState<boolean[]>([true])

  const allTargets = [...targets1, ...targets2]
  useEffect(() => {
    if (allTargets.length !== checked.length) {
      setChecked(
        allTargets.map((t) => {
          if (t.kind === "user_attr") {
            return false
          }
          if (t.kind !== "params" || study === null) {
            return true
          }
          // By default, params that is not included in intersection search space should be disabled,
          // otherwise all trials are filtered.
          return (
            study.intersection_search_space.find((s) => s.name === t.key) !==
            undefined
          )
        })
      )
    }
  }, [allTargets])

  const handleOnChange = (event: React.ChangeEvent<HTMLInputElement>) => {
    setChecked(
      checked.map((c, i) =>
        i.toString() === event.target.name ? event.target.checked : c
      )
    )
  }

  const renderCheckBoxes = (): ReactNode => (
    <FormGroup>
      {allTargets.map((t, i) => {
        return (
          <FormControlLabel
            key={i}
            control={
              <Checkbox
                checked={checked.length > i ? checked[i] : true}
                onChange={handleOnChange}
                name={i.toString()}
              />
            }
            label={t.toLabel(study?.objective_names)}
          />
        )
      })}
    </FormGroup>
  )

  const targets = allTargets.filter((t, i) =>
    checked.length > i ? checked[i] : true
  )
  return [targets, searchSpace, renderCheckBoxes]
}

export const GraphParallelCoordinate: FC<{
  study: StudyDetail | null
}> = ({ study = null }) => {
  const theme = useTheme()
  const [targets, searchSpace, renderCheckBoxes] = useTargets(study)

  const trials = useFilteredTrials(study, targets, false)
  useEffect(() => {
    if (study !== null) {
      plotCoordinate(study, trials, targets, searchSpace, theme.palette.mode)
    }
  }, [study, trials, targets, searchSpace, theme.palette.mode])

  return (
    <Grid container direction="row">
      <Grid
        item
        xs={3}
        container
        direction="column"
        sx={{
          paddingRight: theme.spacing(2),
          display: "flex",
          flexDirection: "column",
        }}
      >
        <Typography
          variant="h6"
          sx={{ margin: "1em 0", fontWeight: theme.typography.fontWeightBold }}
        >
          Parallel Coordinate
        </Typography>
        {renderCheckBoxes()}
      </Grid>
      <Grid item xs={9}>
        <Box id={plotDomId} sx={{ height: "450px" }} />
      </Grid>
    </Grid>
  )
}

const plotCoordinate = (
  study: StudyDetail,
  trials: Trial[],
  targets: Target[],
  searchSpace: SearchSpaceItem[],
  mode: string
) => {
  if (document.getElementById(plotDomId) === null) {
    return
  }

  const layout: Partial<plotly.Layout> = {
    margin: {
      l: 70,
      t: 50,
      r: 50,
      b: 100,
    },
    template: mode === "dark" ? plotlyDarkTemplate : {},
    uirevision: "true",
  }
  if (trials.length === 0 || targets.length === 0) {
    plotly.react(plotDomId, [], layout)
    return
  }

  const maxLabelLength = 40
  const breakLength = maxLabelLength / 2
  const ellipsis = "…"
  const truncateLabelIfTooLong = (originalLabel: string): string => {
    return originalLabel.length > maxLabelLength
      ? originalLabel.substring(0, maxLabelLength - ellipsis.length) + ellipsis
      : originalLabel
  }
  const breakLabelIfTooLong = (originalLabel: string): string => {
    const truncated = truncateLabelIfTooLong(originalLabel)
    return truncated
      .split("")
      .map((c, i) => {
        return (i + 1) % breakLength == 0 ? c + "<br>" : c
      })
      .join("")
  }

  const dimensions = targets.map((target) => {
    if (target.kind === "objective" || target.kind === "user_attr") {
      const values: number[] = trials.map(
        (t) => target.getTargetValue(t) as number
      )
      return {
        label: target.toLabel(study.objective_names),
        values: values,
        range: [Math.min(...values), Math.max(...values)],
      }
    } else {
      const s = searchSpace.find(
        (s) => s.name === target.key
      ) as SearchSpaceItem // Must be already filtered.

      const values: number[] = trials.map(
        (t) => target.getTargetValue(t) as number
      )
      if (s.distribution.type !== "CategoricalDistribution") {
        return {
          label: breakLabelIfTooLong(s.name),
          values: values,
          range: [s.distribution.low, s.distribution.high],
        }
      } else {
        // categorical
        const vocabArr: string[] = s.distribution.choices.map((c) => c.value)
        const tickvals: number[] = vocabArr.map((v, i) => i)
        return {
          label: breakLabelIfTooLong(s.name),
          values: values,
          range: [0, s.distribution.choices.length - 1],
          // @ts-ignore
          tickvals: tickvals,
          ticktext: vocabArr,
        }
      }
    }
  })
  if (dimensions.length === 0) {
    console.log("Must not reach here.")
    plotly.react(plotDomId, [], layout)
    return
  }
  let reversescale = false
  if (
    targets[0].kind === "objective" &&
    (targets[0].getObjectiveId() as number) < study.directions.length &&
    study.directions[targets[0].getObjectiveId() as number] === "maximize"
  ) {
    reversescale = true
  }
  const plotData: Partial<plotly.PlotData>[] = [
    {
      type: "parcoords",
      dimensions: dimensions,
      labelangle: 30,
      labelside: "bottom",
      line: {
        color: dimensions[0]["values"],
        // @ts-ignore
        colorscale: "Blues",
        colorbar: {
          title: targets[0].toLabel(study.objective_names),
        },
        showscale: true,
        reversescale: reversescale,
      },
    },
  ]

  plotly.react(plotDomId, plotData, layout)
}