import { useCallback, useEffect, useReducer, useRef, useState } from 'react'
import { Label } from '../../../lib/networking/fragments/labelFragment'
import { HStack, SpanBox, VStack } from '../../elements/LayoutPrimitives'
import {
  ModalRoot,
  ModalOverlay,
  ModalContent,
  ModalTitleBar,
} from '../../elements/ModalPrimitives'
import { SetLabelsControl } from './SetLabelsControl'
import { createLabelMutation } from '../../../lib/networking/mutations/createLabelMutation'
import { showSuccessToast } from '../../../lib/toastHelpers'
import { useGetLabelsQuery } from '../../../lib/networking/queries/useGetLabelsQuery'
import { v4 as uuidv4 } from 'uuid'
import { randomLabelColorHex } from '../../../utils/settings-page/labels/labelColorObjects'
import { LabelAction } from '../../../lib/hooks/useSetPageLabels'
import { Button } from '../../elements/Button'

type AddBulkLabelsModalProps = {
  onOpenChange: (open: boolean) => void
  bulkSetLabels: (labels: Label[]) => void
}

export function AddBulkLabelsModal(
  props: AddBulkLabelsModalProps
): JSX.Element {
  const availableLabels = useGetLabelsQuery()
  const [tabCount, setTabCount] = useState(-1)
  const [inputValue, setInputValue] = useState('')
  const [tabStartValue, setTabStartValue] = useState('')
  const [errorMessage, setErrorMessage] =
    useState<string | undefined>(undefined)
  const errorTimeoutRef = useRef<NodeJS.Timeout | undefined>()
  const [highlightLastLabel, setHighlightLastLabel] = useState(false)
  const [isSaving, setIsSaving] = useState(false)

  const labelsReducer = (
    state: {
      labels: Label[]
    },
    action: {
      type: LabelAction
      labels: Label[]
    }
  ) => {
    return {
      labels: action.labels,
    }
  }

  const [selectedLabels, dispatchLabels] = useReducer(labelsReducer, {
    labels: [],
  })

  const showMessage = useCallback(
    (msg: string, timeout?: number) => {
      if (errorTimeoutRef.current) {
        clearTimeout(errorTimeoutRef.current)
        errorTimeoutRef.current = undefined
      }
      setErrorMessage(msg)
      if (timeout) {
        errorTimeoutRef.current = setTimeout(() => {
          setErrorMessage(undefined)
          if (errorTimeoutRef.current) {
            clearTimeout(errorTimeoutRef.current)
            errorTimeoutRef.current = undefined
          }
        }, timeout)
      }
    },
    [errorTimeoutRef]
  )

  useEffect(() => {
    const maxLengthMessage = 'Max label length: 48 chars'

    if (inputValue.length >= 48) {
      showMessage(maxLengthMessage)
    } else if (errorMessage === maxLengthMessage) {
      setErrorMessage(undefined)
    }

    if (inputValue.length > 0) {
      setHighlightLastLabel(false)
    }
  }, [errorMessage, inputValue, showMessage])

  const clearInputState = useCallback(() => {
    setTabCount(-1)
    setInputValue('')
    setTabStartValue('')
    setHighlightLastLabel(false)
  }, [])

  const createLabelAsync = useCallback(
    (newLabels: Label[], tempLabel: Label) => {
      ;(async () => {
        const currentLabels = newLabels
        const newLabel = await createLabelMutation(
          tempLabel.name,
          tempLabel.color
        )
        const idx = currentLabels.findIndex((l) => l.id === tempLabel.id)
        if (newLabel) {
          showSuccessToast(`Created label ${newLabel.name}`, {
            position: 'bottom-right',
          })
          if (idx !== -1) {
            currentLabels[idx] = newLabel
            dispatchLabels({ type: 'SAVE', labels: [...currentLabels] })
          } else {
            dispatchLabels({
              type: 'SAVE',
              labels: [...currentLabels, newLabel],
            })
          }
        } else {
          showMessage(`Error creating label ${tempLabel.name}`, 5000)
          if (idx !== -1) {
            currentLabels.splice(idx, 1)
            dispatchLabels({ type: 'SAVE', labels: [...currentLabels] })
          }
        }
      })()
    },
    [dispatchLabels, showMessage]
  )

  const selectOrCreateLabel = useCallback(
    (value: string) => {
      const trimmedValue = value.trim()
      const current = selectedLabels.labels ?? []
      const lowerCasedValue = trimmedValue.toLowerCase()
      const existing = availableLabels.labels.find(
        (l) => l.name.toLowerCase() == lowerCasedValue
      )

      if (lowerCasedValue.length < 1) {
        return
      }

      if (existing) {
        const isAdded = selectedLabels.labels.find(
          (l) => l.name.toLowerCase() == lowerCasedValue
        )
        if (!isAdded) {
          dispatchLabels({ type: 'SAVE', labels: [...current, existing] })
          clearInputState()
        } else {
          showMessage(`label ${trimmedValue} already added.`, 5000)
        }
      } else {
        const tempLabel = {
          id: uuidv4(),
          name: trimmedValue,
          color: randomLabelColorHex(),
          description: '',
          createdAt: new Date(),
        }
        const newLabels = [...current, tempLabel]
        dispatchLabels({ type: 'TEMP', labels: newLabels })
        clearInputState()

        createLabelAsync(newLabels, tempLabel)
      }
    },
    [
      availableLabels,
      selectedLabels,
      dispatchLabels,
      clearInputState,
      createLabelAsync,
      showMessage,
    ]
  )

  const deleteLastLabel = useCallback(() => {
    if (highlightLastLabel) {
      const current = selectedLabels.labels
      current.pop()
      dispatchLabels({ type: 'SAVE', labels: [...current] })
      setHighlightLastLabel(false)
    } else {
      setHighlightLastLabel(true)
    }
  }, [highlightLastLabel, selectedLabels, dispatchLabels])

  const handleSave = useCallback(() => {
    props.bulkSetLabels(selectedLabels.labels)
    props.onOpenChange(true)
  }, [selectedLabels])

  return (
    <ModalRoot defaultOpen onOpenChange={props.onOpenChange}>
      <ModalOverlay />
      <ModalContent
        tabIndex={0}
        css={{
          border: '1px solid $grayBorder',
          backgroundColor: '$thBackground',
        }}
        onPointerDownOutside={(event) => {
          event.preventDefault()
          props.onOpenChange(false)
        }}
        onEscapeKeyDown={(event) => {
          props.onOpenChange(false)
          event.preventDefault()
        }}
      >
        <VStack distribution="start" css={{ height: '100%' }}>
          <SpanBox css={{ pt: '0px', px: '16px', width: '100%' }}>
            <ModalTitleBar
              title="Add labels to selected items"
              onOpenChange={props.onOpenChange}
            />
          </SpanBox>
          <SetLabelsControl
            inputValue={inputValue}
            setInputValue={setInputValue}
            clearInputState={clearInputState}
            selectedLabels={selectedLabels.labels}
            dispatchLabels={dispatchLabels}
            tabCount={tabCount}
            setTabCount={setTabCount}
            tabStartValue={tabStartValue}
            setTabStartValue={setTabStartValue}
            highlightLastLabel={highlightLastLabel}
            setHighlightLastLabel={setHighlightLastLabel}
            deleteLastLabel={deleteLastLabel}
            selectOrCreateLabel={selectOrCreateLabel}
            errorMessage={errorMessage}
            footer={
              <HStack
                distribution="end"
                css={{ width: '100%', pb: '20px', px: '20px' }}
              >
                <Button
                  disabled={isSaving}
                  style="ctaDarkYellow"
                  onClick={(event) => {
                    handleSave()
                    event.preventDefault()
                  }}
                  css={{ fontSize: '10px', p: '10px', fontFamily: '$inter' }}
                >
                  Add Labels
                </Button>
              </HStack>
            }
          />
        </VStack>
      </ModalContent>
    </ModalRoot>
  )
}