import { useState, useCallback, useEffect } from 'react'
import { Popover, PopoverContent, PopoverTrigger } from '@/components/ui/Popover'
import Checkbox from '@/components/ui/Checkbox'
import Button from '@/components/ui/Button'
import Separator from '@/components/ui/Separator'
import Input from '@/components/ui/Input'

import { controlButtonVariant } from '@/lib/constants'
import { useSettingsStore } from '@/stores/settings'
import { useBackendState } from '@/stores/state'

import { SettingsIcon, RefreshCwIcon } from 'lucide-react'

/**
 * Component that displays a checkbox with a label.
 */
const LabeledCheckBox = ({
  checked,
  onCheckedChange,
  label
}: {
  checked: boolean
  onCheckedChange: () => void
  label: string
}) => {
  return (
    <div className="flex items-center gap-2">
      <Checkbox checked={checked} onCheckedChange={onCheckedChange} />
      <label
        htmlFor="terms"
        className="text-sm leading-none font-medium peer-disabled:cursor-not-allowed peer-disabled:opacity-70"
      >
        {label}
      </label>
    </div>
  )
}

/**
 * Component that displays a number input with a label.
 */
const LabeledNumberInput = ({
  value,
  onEditFinished,
  label,
  min,
  max
}: {
  value: number
  onEditFinished: (value: number) => void
  label: string
  min: number
  max?: number
}) => {
  const [currentValue, setCurrentValue] = useState<number | null>(value)

  const onValueChange = useCallback(
    (e: React.ChangeEvent<HTMLInputElement>) => {
      const text = e.target.value.trim()
      if (text.length === 0) {
        setCurrentValue(null)
        return
      }
      const newValue = Number.parseInt(text)
      if (!isNaN(newValue) && newValue !== currentValue) {
        if (min !== undefined && newValue < min) {
          return
        }
        if (max !== undefined && newValue > max) {
          return
        }
        setCurrentValue(newValue)
      }
    },
    [currentValue, min, max]
  )

  const onBlur = useCallback(() => {
    if (currentValue !== null && value !== currentValue) {
      onEditFinished(currentValue)
    }
  }, [value, currentValue, onEditFinished])

  return (
    <div className="flex flex-col gap-2">
      <label
        htmlFor="terms"
        className="text-sm leading-none font-medium peer-disabled:cursor-not-allowed peer-disabled:opacity-70"
      >
        {label}
      </label>
      <Input
        type="number"
        value={currentValue === null ? '' : currentValue}
        onChange={onValueChange}
        className="h-6 w-full min-w-0 pr-1"
        min={min}
        max={max}
        onBlur={onBlur}
        onKeyDown={(e) => {
          if (e.key === 'Enter') {
            onBlur()
          }
        }}
      />
    </div>
  )
}

/**
 * Component that displays a popover with settings options.
 */
export default function Settings() {
  const [opened, setOpened] = useState<boolean>(false)
  const [tempApiKey, setTempApiKey] = useState<string>('')
  const refreshLayout = useSettingsStore.use.refreshLayout()

  const showPropertyPanel = useSettingsStore.use.showPropertyPanel()
  const showNodeSearchBar = useSettingsStore.use.showNodeSearchBar()
  const showNodeLabel = useSettingsStore.use.showNodeLabel()
  const enableEdgeEvents = useSettingsStore.use.enableEdgeEvents()
  const enableNodeDrag = useSettingsStore.use.enableNodeDrag()
  const enableHideUnselectedEdges = useSettingsStore.use.enableHideUnselectedEdges()
  const showEdgeLabel = useSettingsStore.use.showEdgeLabel()
  const graphQueryMaxDepth = useSettingsStore.use.graphQueryMaxDepth()
  const graphMinDegree = useSettingsStore.use.graphMinDegree()
  const graphLayoutMaxIterations = useSettingsStore.use.graphLayoutMaxIterations()

  const enableHealthCheck = useSettingsStore.use.enableHealthCheck()
  const apiKey = useSettingsStore.use.apiKey()

  useEffect(() => {
    setTempApiKey(apiKey || '')
  }, [apiKey, opened])

  const setEnableNodeDrag = useCallback(
    () => useSettingsStore.setState((pre) => ({ enableNodeDrag: !pre.enableNodeDrag })),
    []
  )
  const setEnableEdgeEvents = useCallback(
    () => useSettingsStore.setState((pre) => ({ enableEdgeEvents: !pre.enableEdgeEvents })),
    []
  )
  const setEnableHideUnselectedEdges = useCallback(
    () =>
      useSettingsStore.setState((pre) => ({
        enableHideUnselectedEdges: !pre.enableHideUnselectedEdges
      })),
    []
  )
  const setShowEdgeLabel = useCallback(
    () =>
      useSettingsStore.setState((pre) => ({
        showEdgeLabel: !pre.showEdgeLabel
      })),
    []
  )

  //
  const setShowPropertyPanel = useCallback(
    () => useSettingsStore.setState((pre) => ({ showPropertyPanel: !pre.showPropertyPanel })),
    []
  )

  const setShowNodeSearchBar = useCallback(
    () => useSettingsStore.setState((pre) => ({ showNodeSearchBar: !pre.showNodeSearchBar })),
    []
  )

  const setShowNodeLabel = useCallback(
    () => useSettingsStore.setState((pre) => ({ showNodeLabel: !pre.showNodeLabel })),
    []
  )

  const setEnableHealthCheck = useCallback(
    () => useSettingsStore.setState((pre) => ({ enableHealthCheck: !pre.enableHealthCheck })),
    []
  )

  const setGraphQueryMaxDepth = useCallback((depth: number) => {
    if (depth < 1) return
    useSettingsStore.setState({ graphQueryMaxDepth: depth })
  }, [])

  const setGraphMinDegree = useCallback((degree: number) => {
    if (degree < 0) return
    useSettingsStore.setState({ graphMinDegree: degree })
  }, [])

  const setGraphLayoutMaxIterations = useCallback((iterations: number) => {
    if (iterations < 1) return
    useSettingsStore.setState({ graphLayoutMaxIterations: iterations })
  }, [])

  const setApiKey = useCallback(async () => {
    useSettingsStore.setState({ apiKey: tempApiKey || null })
    await useBackendState.getState().check()
    setOpened(false)
  }, [tempApiKey])

  const handleTempApiKeyChange = useCallback(
    (e: React.ChangeEvent<HTMLInputElement>) => {
      setTempApiKey(e.target.value)
    },
    [setTempApiKey]
  )

  return (
    <>
      <Button
        variant={controlButtonVariant}
        tooltip="Refresh Layout"
        size="icon"
        onClick={refreshLayout}
      >
        <RefreshCwIcon />
      </Button>
      <Popover open={opened} onOpenChange={setOpened}>
        <PopoverTrigger asChild>
          <Button variant={controlButtonVariant} tooltip="Settings" size="icon">
            <SettingsIcon />
          </Button>
        </PopoverTrigger>
        <PopoverContent
          side="right"
          align="start"
          className="mb-2 p-2"
          onCloseAutoFocus={(e) => e.preventDefault()}
        >
          <div className="flex flex-col gap-2">
            <LabeledCheckBox
              checked={enableHealthCheck}
              onCheckedChange={setEnableHealthCheck}
              label="Health Check"
            />

            <Separator />

            <LabeledCheckBox
              checked={showPropertyPanel}
              onCheckedChange={setShowPropertyPanel}
              label="Show Property Panel"
            />
            <LabeledCheckBox
              checked={showNodeSearchBar}
              onCheckedChange={setShowNodeSearchBar}
              label="Show Search Bar"
            />

            <Separator />

            <LabeledCheckBox
              checked={showNodeLabel}
              onCheckedChange={setShowNodeLabel}
              label="Show Node Label"
            />
            <LabeledCheckBox
              checked={enableNodeDrag}
              onCheckedChange={setEnableNodeDrag}
              label="Node Draggable"
            />

            <Separator />

            <LabeledCheckBox
              checked={showEdgeLabel}
              onCheckedChange={setShowEdgeLabel}
              label="Show Edge Label"
            />
            <LabeledCheckBox
              checked={enableHideUnselectedEdges}
              onCheckedChange={setEnableHideUnselectedEdges}
              label="Hide Unselected Edges"
            />
            <LabeledCheckBox
              checked={enableEdgeEvents}
              onCheckedChange={setEnableEdgeEvents}
              label="Edge Events"
            />

            <Separator />
            <LabeledNumberInput
              label="Max Query Depth"
              min={1}
              value={graphQueryMaxDepth}
              onEditFinished={setGraphQueryMaxDepth}
            />
            <LabeledNumberInput
              label="Minimum Degree"
              min={0}
              value={graphMinDegree}
              onEditFinished={setGraphMinDegree}
            />
            <LabeledNumberInput
              label="Max Layout Iterations"
              min={1}
              max={20}
              value={graphLayoutMaxIterations}
              onEditFinished={setGraphLayoutMaxIterations}
            />

            <Separator />

            <div className="flex flex-col gap-2">
              <label className="text-sm font-medium">API Key</label>
              <form className="flex h-6 gap-2" onSubmit={(e) => e.preventDefault()}>
                <div className="w-0 flex-1">
                  <Input
                    type="password"
                    value={tempApiKey}
                    onChange={handleTempApiKeyChange}
                    placeholder="Enter your API key"
                    className="max-h-full w-full min-w-0"
                    autoComplete="off"
                  />
                </div>
                <Button
                  onClick={setApiKey}
                  variant="outline"
                  size="sm"
                  className="max-h-full shrink-0"
                >
                  Save
                </Button>
              </form>
            </div>
          </div>
        </PopoverContent>
      </Popover>
    </>
  )
}
