import { Loading } from '@/components/shared'
import { lazy, useEffect, useMemo, useRef, useState } from 'react'
import { useParams, useSearchParams } from 'react-router-dom'
import type { DataType } from 'devextreme/common'
import type { SimpleItem } from 'devextreme/ui/form'
import FormButtons from './FormButtons'
import { FormProps } from './types'
import { useGridData } from './useFormData'
import { getList } from '@/services/form.service'
import { applyNewRowDefaults, castValueByDataType } from '../list/shared/editingForm'
import { FormPageShell } from './shared/FormPageShell'

const FormView = lazy(() => import('./FormView'))

export const FormNewContent = (props: FormProps = { isSubForm: false }) => {
  const mode = 'new'
  const { isSubForm, level, sParams, onActionView } = props
  const params = useParams()
  const listFormCode = props?.listFormCode ?? params?.listFormCode ?? ''
  const [searchParams] = useSearchParams()
  const initializedListFormCodeRef = useRef<string | undefined>(undefined)

  const {
    setFormData,
    loading,
    handleSubmit,
    gridDto,
    dataSource,
    commandColumnData,
    formData,
    formItems,
    refForm,
    permissionResults,
    fieldOrder,
    previewFieldOrder,
    saveFieldOrder,
    canStoreFieldOrder,
  } = useGridData({
    mode,
    listFormCode,
    level,
    isSubForm,
    onSubmitAction: onActionView,
  })

  // URL parametreleri + üst formdan gelen parametreler.
  const newParams = useMemo(
    () =>
      new URLSearchParams({
        ...Object.fromEntries(searchParams),
        ...Object.fromEntries(sParams ?? []),
      }),
    [searchParams, sParams],
  )

  useEffect(() => {
    initializedListFormCodeRef.current = undefined
  }, [listFormCode])

  /** Form ilk açıldığında varsayılan değerleri kurar. */
  useEffect(() => {
    if (!formItems?.length || !gridDto?.columnFormats) return
    if (initializedListFormCodeRef.current === listFormCode) return

    initializedListFormCodeRef.current = listFormCode
    let isActive = true

    // Tanımlı tüm alanlar önce boşaltılır, ardından kolon varsayılanları uygulanır.
    const initialData: Record<string, any> = {}
    formItems.forEach((group) =>
      (group.items as SimpleItem[] | undefined)?.forEach((item) => {
        if (item.dataField) initialData[item.dataField] = undefined
      }),
    )

    applyNewRowDefaults(gridDto, initialData).then((data) => {
      if (isActive) setFormData(data)
    })

    return () => {
      isActive = false
    }
  }, [listFormCode, formItems?.length, gridDto?.columnFormats])

  /** URL parametrelerinden gelen alanları forma yazar. */
  useEffect(() => {
    if (!formItems?.length || !formData || !gridDto?.columnFormats) return

    const updatedData = { ...formData }
    let hasChanges = false

    for (const colFormat of gridDto.columnFormats) {
      const fieldName = colFormat.fieldName
      if (!fieldName || !newParams.has(fieldName)) continue

      const nextValue = castValueByDataType(
        newParams.get(fieldName),
        colFormat.dataType as DataType,
      )
      if (updatedData[fieldName] !== nextValue) {
        updatedData[fieldName] = nextValue
        hasChanges = true
      }
    }

    if (hasChanges) setFormData(updatedData)
  }, [newParams, formData, gridDto?.columnFormats])

  /** URL'den gelen alanlar kullanıcı tarafından değiştirilemez. */
  useEffect(() => {
    if (!formItems?.length || !gridDto?.columnFormats) return

    const lockedFields = new Set(
      gridDto.columnFormats
        .map((colFormat) => colFormat.fieldName)
        .filter((fieldName): fieldName is string => !!fieldName && newParams.has(fieldName)),
    )
    if (!lockedFields.size) return

    formItems.forEach((group) =>
      (group.items as SimpleItem[] | undefined)?.forEach((item) => {
        if (item.dataField && lockedFields.has(item.dataField)) {
          item.editorOptions = { ...item.editorOptions, readOnly: true }
        }
      }),
    )
  }, [formItems, newParams, gridDto?.columnFormats])

  return (
    <FormPageShell
      mode={mode}
      listFormCode={listFormCode}
      isSubForm={isSubForm}
      level={level}
      loading={loading}
      gridDto={gridDto}
      formData={formData}
      formItems={formItems}
      refForm={refForm}
      setFormData={setFormData}
      showSubForms={false}
      actions={
        permissionResults && (
          <FormButtons
            fieldOrder={
              canStoreFieldOrder
                ? { value: fieldOrder, preview: previewFieldOrder, save: saveFieldOrder }
                : undefined
            }
            isSubForm={isSubForm}
            mode={mode}
            listFormCode={listFormCode}
            id={formData?.Id}
            gridDto={gridDto!}
            commandColumnData={commandColumnData!}
            dataSource={dataSource!}
            permissions={permissionResults}
            handleSubmit={handleSubmit}
            refreshData={() => {}}
            getSelectedRowKeys={() => []}
            getSelectedRowsData={() => [formData]}
            getFilter={() => []}
            onActionView={onActionView}
          />
        )
      }
    />
  )
}

/**
 * `listFormType === 'Form'` olan liste formlarında "yeni kayıt" ekranı yerine
 * doğrudan görüntüleme ekranı açılır (tekil kayıtlı formlar).
 */
const FormNew = (props: FormProps = { isSubForm: false }) => {
  const params = useParams()
  const listFormCode = props.listFormCode ?? params.listFormCode ?? ''
  const [listFormType, setListFormType] = useState<string>()
  const [loading, setLoading] = useState(true)

  useEffect(() => {
    if (!listFormCode || props.isSubForm) {
      setLoading(false)
      return
    }

    let isActive = true
    setLoading(true)

    getList({ listFormCode })
      .then((response: any) => {
        if (isActive) setListFormType(response?.data?.gridOptions?.listFormType)
      })
      .catch((error: unknown) => console.error('ListForm tipi alınamadı:', error))
      .finally(() => {
        if (isActive) setLoading(false)
      })

    return () => {
      isActive = false
    }
  }, [listFormCode, props.isSubForm])

  if (loading) {
    return <Loading loading type="default" />
  }

  if (!props.isSubForm && listFormType === 'Form') {
    return <FormView {...props} listFormCode={listFormCode} />
  }

  return <FormNewContent {...props} listFormCode={listFormCode} />
}

export default FormNew