import type React from 'react'
import { useCallback, useEffect, useMemo, useRef, useState } from 'react'
import { X } from 'lucide-react'
import { Button, Combobox as EditableCombobox } from '@/components/emcn/components'
import { formatDisplayText } from '@/app/workspace/[workspaceId]/w/[workflowId]/components/panel/components/editor/components/sub-block/components/formatted-text'
import { SubBlockInputController } from '@/app/workspace/[workspaceId]/w/[workflowId]/components/panel/components/editor/components/sub-block/components/sub-block-input-controller'
import { getWorkflowSearchLabelHighlight } from '@/app/workspace/[workspaceId]/w/[workflowId]/components/panel/components/editor/components/sub-block/components/workflow-search-highlight'
import { useSubBlockValue } from '@/app/workspace/[workspaceId]/w/[workflowId]/components/panel/components/editor/components/sub-block/hooks/use-sub-block-value'
import { useActiveSearchTarget } from '@/app/workspace/[workspaceId]/w/[workflowId]/components/panel/components/editor/providers/active-search-target-provider'
import type { SubBlockConfig } from '@/blocks/types'
import type { SelectorContext, SelectorKey } from '@/hooks/selectors/types'
import {
  useSelectorOptionDetail,
  useSelectorOptionMap,
  useSelectorOptions,
} from '@/hooks/selectors/use-selector-query'

interface SelectorComboboxProps {
  blockId: string
  subBlock: SubBlockConfig
  selectorKey: SelectorKey
  selectorContext: SelectorContext
  disabled?: boolean
  isPreview?: boolean
  previewValue?: string | null
  placeholder?: string
  readOnly?: boolean
  onOptionChange?: (value: string) => void
  allowSearch?: boolean
  missingOptionLabel?: string
}

export function SelectorCombobox({
  blockId,
  subBlock,
  selectorKey,
  selectorContext,
  disabled,
  isPreview,
  previewValue,
  placeholder,
  readOnly,
  onOptionChange,
  allowSearch = true,
  missingOptionLabel,
}: SelectorComboboxProps) {
  const activeSearchTarget = useActiveSearchTarget()
  const [storeValueRaw, setStoreValue] = useSubBlockValue<string | null | undefined>(
    blockId,
    subBlock.id
  )
  const storeValue = storeValueRaw ?? undefined
  const previewedValue = previewValue ?? undefined
  const activeValue: string | undefined = isPreview ? previewedValue : storeValue
  const [searchTerm, setSearchTerm] = useState('')
  const [isEditing, setIsEditing] = useState(false)
  const {
    data: options = [],
    isLoading,
    hasMore,
    error,
  } = useSelectorOptions(selectorKey, {
    context: selectorContext,
    search: allowSearch ? searchTerm : undefined,
  })
  const { data: detailOption } = useSelectorOptionDetail(selectorKey, {
    context: selectorContext,
    detailId: activeValue,
  })
  const optionMap = useSelectorOptionMap(options, detailOption ?? undefined)
  const hasMissingOption =
    Boolean(activeValue) &&
    Boolean(missingOptionLabel) &&
    !isLoading &&
    !hasMore &&
    !optionMap.get(activeValue!)
  const selectedLabel: string = activeValue
    ? hasMissingOption
      ? (missingOptionLabel ?? activeValue)
      : (optionMap.get(activeValue)?.label ?? activeValue)
    : ''
  const [inputValue, setInputValue] = useState(selectedLabel)
  const previousActiveValue = useRef<string | undefined>(activeValue)

  useEffect(() => {
    if (previousActiveValue.current !== activeValue) {
      previousActiveValue.current = activeValue
      setIsEditing(false)
    }
  }, [activeValue])

  useEffect(() => {
    if (!allowSearch) return
    if (!isEditing) {
      setInputValue(selectedLabel)
    }
  }, [selectedLabel, allowSearch, isEditing])

  const comboboxOptions = useMemo(
    () =>
      Array.from(optionMap.values()).map((option) => ({
        label: option.label,
        value: option.id,
      })),
    [optionMap]
  )

  const handleSelection = useCallback(
    (value: string) => {
      if (readOnly || disabled) return
      setStoreValue(value)
      setIsEditing(false)
      onOptionChange?.(value)
    },
    [setStoreValue, onOptionChange, readOnly, disabled]
  )

  const handleClear = useCallback(
    (e: React.MouseEvent) => {
      e.preventDefault()
      e.stopPropagation()
      if (readOnly || disabled) return
      setStoreValue(null)
      setInputValue('')
      onOptionChange?.('')
    },
    [setStoreValue, onOptionChange, readOnly, disabled]
  )

  const showClearButton = Boolean(activeValue) && !disabled && !readOnly
  const displayValue = allowSearch ? inputValue : selectedLabel
  const workflowSearchHighlight = getWorkflowSearchLabelHighlight({
    activeSearchTarget,
    blockId,
    subBlockId: subBlock.id,
    valuePath: [],
    label: displayValue,
  })

  return (
    <div className='w-full'>
      <SubBlockInputController
        blockId={blockId}
        subBlockId={subBlock.id}
        config={subBlock}
        value={activeValue ?? ''}
        disabled={disabled || readOnly}
        isPreview={isPreview}
      >
        {({ ref, onDrop, onDragOver }) => (
          <div className='relative w-full'>
            <EditableCombobox
              options={comboboxOptions}
              value={displayValue}
              selectedValue={activeValue ?? ''}
              onChange={(newValue) => {
                const matched = optionMap.get(newValue)
                if (matched) {
                  setInputValue(matched.label)
                  setIsEditing(false)
                  handleSelection(matched.id)
                  return
                }
                if (allowSearch) {
                  setInputValue(newValue)
                  setIsEditing(true)
                  setSearchTerm(newValue)
                }
              }}
              placeholder={placeholder || subBlock.placeholder || 'Select an option'}
              disabled={disabled || readOnly}
              editable={allowSearch}
              filterOptions={allowSearch}
              inputRef={ref as React.RefObject<HTMLInputElement>}
              inputProps={{
                onDrop: onDrop as (e: React.DragEvent<HTMLInputElement>) => void,
                onDragOver: onDragOver as (e: React.DragEvent<HTMLInputElement>) => void,
                className: showClearButton ? 'pr-[60px]' : undefined,
              }}
              isLoading={isLoading}
              error={error instanceof Error ? error.message : null}
              overlayContent={
                workflowSearchHighlight ? (
                  <span className='block truncate'>
                    {formatDisplayText(displayValue, { workflowSearchHighlight })}
                  </span>
                ) : undefined
              }
            />
            {showClearButton && (
              <Button
                type='button'
                variant='ghost'
                className='-translate-y-1/2 absolute top-1/2 right-[28px] z-10 size-6 p-0'
                onClick={handleClear}
              >
                <X className='size-4 opacity-50 hover-hover:opacity-100' />
              </Button>
            )}
          </div>
        )}
      </SubBlockInputController>
    </div>
  )
}
