import { useState, useCallback, useMemo, useEffect } from 'react'
import { createPortal } from 'react-dom'
import { Button, Dialog, Notification, toast, Checkbox } from '@/components/ui'
import {
  FaPlus,
  FaTrash,
  FaArrowUp,
  FaArrowDown,
  FaTable,
  FaCloudUploadAlt,
  FaCheck,
  FaLink,
  FaEdit,
  FaTimes,
  FaArrowRight,
} from 'react-icons/fa'
import { sqlObjectManagerService } from '@/services/sql-query-manager.service'
import { MenuService } from '@/services/menu.service'
import { useLocalization } from '@/utils/hooks/useLocalization'
import { CascadeBehavior, SqlTableRelation, RelationshipType } from '@/proxy/developerKit/models'

// ─── Types ────────────────────────────────────────────────────────────────────

type SqlDataType =
  | 'nvarchar'
  | 'nvarchar(MAX)'
  | 'int'
  | 'bigint'
  | 'decimal'
  | 'float'
  | 'bit'
  | 'datetime2'
  | 'date'
  | 'uniqueidentifier'
  | 'money'

interface ColumnDefinition {
  id: string
  columnName: string
  dataType: SqlDataType
  maxLength: string
  isNullable: boolean
  defaultValue: string
  description: string
}

interface MenuOption {
  value: string
  label: string
}

interface TableSettings {
  menuValue: string
  menuPrefix: string
  entityName: string
  tableName: string
}

interface TableDesignerDialogProps {
  isOpen: boolean
  onClose: () => void
  dataSource: string | null
  onDeployed?: () => void
  initialTableData?: { schemaName: string; tableName: string } | null
}

// ─── Constants ────────────────────────────────────────────────────────────────

const DATA_TYPES: { value: SqlDataType; label: string }[] = [
  { value: 'nvarchar', label: 'String (nvarchar)' },
  { value: 'nvarchar(MAX)', label: 'Text (nvarchar MAX)' },
  { value: 'int', label: 'Int (int)' },
  { value: 'bigint', label: 'Long (bigint)' },
  { value: 'decimal', label: 'Decimal (decimal 18,4)' },
  { value: 'float', label: 'Float (float)' },
  { value: 'bit', label: 'Bool (bit)' },
  { value: 'datetime2', label: 'DateTime (datetime2)' },
  { value: 'date', label: 'Date (date)' },
  { value: 'uniqueidentifier', label: 'Guid (uniqueidentifier)' },
  { value: 'money', label: 'Money (money)' },
]

const FULL_AUDIT_COLUMNS: ColumnDefinition[] = [
  {
    id: '__Id',
    columnName: 'Id',
    dataType: 'uniqueidentifier',
    maxLength: '',
    isNullable: false,
    defaultValue: 'NEWID()',
    description: 'Primary key',
  },
  {
    id: '__CreationTime',
    columnName: 'CreationTime',
    dataType: 'datetime2',
    maxLength: '',
    isNullable: false,
    defaultValue: 'GETUTCDATE()',
    description: 'Record creation time',
  },
  {
    id: '__CreatorId',
    columnName: 'CreatorId',
    dataType: 'uniqueidentifier',
    maxLength: '',
    isNullable: true,
    defaultValue: '',
    description: 'Creator user ID',
  },
  {
    id: '__LastModificationTime',
    columnName: 'LastModificationTime',
    dataType: 'datetime2',
    maxLength: '',
    isNullable: true,
    defaultValue: '',
    description: 'Last modification time',
  },
  {
    id: '__LastModifierId',
    columnName: 'LastModifierId',
    dataType: 'uniqueidentifier',
    maxLength: '',
    isNullable: true,
    defaultValue: '',
    description: 'Last modifier user ID',
  },
  {
    id: '__IsDeleted',
    columnName: 'IsDeleted',
    dataType: 'bit',
    maxLength: '',
    isNullable: false,
    defaultValue: '0',
    description: 'Soft delete flag',
  },
  {
    id: '__DeletionTime',
    columnName: 'DeletionTime',
    dataType: 'datetime2',
    maxLength: '',
    isNullable: true,
    defaultValue: '',
    description: 'Deletion time',
  },
  {
    id: '__DeleterId',
    columnName: 'DeleterId',
    dataType: 'uniqueidentifier',
    maxLength: '',
    isNullable: true,
    defaultValue: '',
    description: 'Deleter user ID',
  },
]

const REL_TYPES: { value: RelationshipType; label: string; desc: string }[] = [
  { value: 'OneToMany', label: '1 → N', desc: 'Bire-çok' },
  { value: 'OneToOne', label: '1 → 1', desc: 'Bire-bir' },
]

const CASCADE_OPTIONS: { value: CascadeBehavior; label: string }[] = [
  { value: 'NoAction', label: 'No Action' },
  { value: 'Cascade', label: 'Cascade' },
  { value: 'SetNull', label: 'Set Null' },
  { value: 'Restrict', label: 'Restrict' },
]

const EMPTY_FK: Omit<SqlTableRelation, 'id'> = {
  relationshipType: 'OneToMany',
  fkColumnName: '',
  referencedTable: '',
  referencedColumn: 'Id',
  cascadeDelete: 'NoAction',
  cascadeUpdate: 'Cascade',
  isRequired: false,
  description: '',
}

const TENANT_COLUMN: ColumnDefinition = {
  id: '__TenantId',
  columnName: 'TenantId',
  dataType: 'uniqueidentifier',
  maxLength: '',
  isNullable: true,
  defaultValue: '',
  description: 'Tenant ID for multi-tenancy',
}

// ─── T-SQL Generator ──────────────────────────────────────────────────────────

function colToSqlLine(col: ColumnDefinition, addComma = true): string {
  let typeSql: string
  switch (col.dataType) {
    case 'nvarchar':
      typeSql = `nvarchar(${col.maxLength || '100'})`
      break
    case 'nvarchar(MAX)':
      typeSql = 'nvarchar(MAX)'
      break
    case 'decimal':
      typeSql = 'decimal(18, 4)'
      break
    default:
      typeSql = col.dataType
  }
  const nullPart = col.isNullable ? 'NULL' : 'NOT NULL'
  const defaultPart = col.defaultValue ? ` DEFAULT ${col.defaultValue}` : ''
  return `    [${col.columnName}] ${typeSql} ${nullPart}${defaultPart}${addComma ? ',' : ''}`
}

function generateCreateTableSql(
  columns: ColumnDefinition[],
  settings: TableSettings,
  relationships: SqlTableRelation[],
): string {
  const tableName = settings.tableName || 'NewTable'
  const fullTableName = `[dbo].[${tableName}]`

  const userCols = columns.filter((c) => c.columnName.trim())
  const allBodyCols = userCols

  const hasIdCol = userCols.some((c) => c.columnName.trim().toLowerCase() === 'id')
  const bodyLines = hasIdCol
    ? [
        ...allBodyCols.map((c) => colToSqlLine(c, true)),
        `    CONSTRAINT [PK_${tableName}] PRIMARY KEY NONCLUSTERED ([Id])`,
      ]
    : allBodyCols.map((c, i) => colToSqlLine(c, i < allBodyCols.length - 1))

  // FK constraint lines
  const fkLines: string[] = []
  for (const rel of relationships) {
    if (!rel.fkColumnName.trim() || !rel.referencedTable.trim()) continue
    const constraintName = `FK_${tableName}_${rel.fkColumnName}`
    const cascadeDelete = rel.cascadeDelete === 'NoAction' ? 'NO ACTION' : rel.cascadeDelete.replace(/([A-Z])/g, ' $1').trim().toUpperCase()
    const cascadeUpdate = rel.cascadeUpdate === 'NoAction' ? 'NO ACTION' : rel.cascadeUpdate.replace(/([A-Z])/g, ' $1').trim().toUpperCase()
    fkLines.push('')
    fkLines.push(`ALTER TABLE ${fullTableName}`)
    fkLines.push(`    ADD CONSTRAINT [${constraintName}]`)
    fkLines.push(`    FOREIGN KEY ([${rel.fkColumnName}])`)
    fkLines.push(`    REFERENCES [dbo].[${rel.referencedTable}] ([${rel.referencedColumn || 'Id'}])`)
    fkLines.push(`    ON DELETE ${cascadeDelete}`)
    fkLines.push(`    ON UPDATE ${cascadeUpdate};`)
  }

  const lines: string[] = [
    `/* ── Table: ${fullTableName} ── */`,
    ...(settings.entityName ? [`/* Entity Name: ${settings.entityName} */`] : []),
    ...(fkLines.length > 0 ? ['/* Foreign Key Constraints */'] : []),
    '',
    `CREATE TABLE ${fullTableName}`,
    `(`,
    ...bodyLines,
    `);`,
    ...fkLines,
    '',
    `/* Verify: SELECT TOP 10 * FROM ${fullTableName}; */`,
  ]

  return lines.join('\n')
}

// ─── Helpers ──────────────────────────────────────────────────────────────────

/** Convert a DatabaseColumnDto (from API) to a ColumnDefinition for the grid */
function dbColToColumnDef(col: {
  columnName: string
  dataType: string
  isNullable: boolean
  maxLength?: number
}): ColumnDefinition {
  const dt = col.dataType.toLowerCase().trim()
  let dataType: SqlDataType = 'nvarchar'
  let maxLength = ''

  if (dt === 'nvarchar' || dt === 'varchar' || dt === 'char' || dt === 'nchar') {
    dataType = col.maxLength === -1 ? 'nvarchar(MAX)' : 'nvarchar'
    maxLength = col.maxLength && col.maxLength > 0 ? String(col.maxLength) : ''
  } else if (dt === 'int') {
    dataType = 'int'
  } else if (dt === 'bigint') {
    dataType = 'bigint'
  } else if (dt === 'decimal' || dt === 'numeric') {
    dataType = 'decimal'
  } else if (dt === 'float' || dt === 'real') {
    dataType = 'float'
  } else if (dt === 'bit') {
    dataType = 'bit'
  } else if (dt.startsWith('datetime') || dt === 'smalldatetime') {
    dataType = 'datetime2'
  } else if (dt === 'date') {
    dataType = 'date'
  } else if (dt === 'uniqueidentifier') {
    dataType = 'uniqueidentifier'
  } else if (dt === 'money' || dt === 'smallmoney') {
    dataType = 'money'
  }

  return {
    id: crypto.randomUUID(),
    columnName: col.columnName,
    dataType,
    maxLength,
    isNullable: col.isNullable,
    defaultValue: '',
    description: '',
  }
}

/** Generate ALTER TABLE diff SQL (edit mode) */
function generateAlterTableSql(
  originalCols: ColumnDefinition[],
  currentCols: ColumnDefinition[],
  tableName: string,
  relationships: SqlTableRelation[],
  originalRelationships: SqlTableRelation[],
): string {
  const fullTableName = `[dbo].[${tableName}]`
  const lines: string[] = [`/* ── ALTER TABLE: ${fullTableName} ── */`, '']
  let hasChanges = false

  // Build id-based maps for O(1) lookup
  const origById = new Map<string, ColumnDefinition>()
  originalCols.forEach((c) => origById.set(c.id, c))

  const curById = new Map<string, ColumnDefinition>()
  currentCols.filter((c) => c.columnName.trim()).forEach((c) => curById.set(c.id, c))

  // ➕ Added columns (id exists in current but NOT in original)
  currentCols
    .filter((c) => c.columnName.trim())
    .forEach((col) => {
      if (!origById.has(col.id)) {
        hasChanges = true
        lines.push(`-- ➕ Yeni Sütun: [${col.columnName}]`)
        lines.push(`ALTER TABLE ${fullTableName}`)
        lines.push(`    ADD ${colToSqlLine(col, false).trimStart()};`)
        lines.push('')
      }
    })

  // ❌ Silinen sütunlar (id exists in original but NOT in current)
  originalCols.forEach((col) => {
    if (!curById.has(col.id)) {
      hasChanges = true
      lines.push(`-- ❌ Silinen Sütun: [${col.columnName}]`)
      lines.push(`ALTER TABLE ${fullTableName}`)
      lines.push(`    DROP COLUMN [${col.columnName}];`)
      lines.push('')
    }
  })

  // ✏️ Renamed / Modified columns (same id in both)
  currentCols
    .filter((c) => c.columnName.trim())
    .forEach((col) => {
      const orig = origById.get(col.id)
      if (!orig) return // new column, already handled above

      const nameChanged = orig.columnName.trim().toLowerCase() !== col.columnName.trim().toLowerCase()
      const typeChanged = orig.dataType !== col.dataType || orig.maxLength !== col.maxLength
      const nullChanged = orig.isNullable !== col.isNullable

      // Rename: use sp_rename to preserve data
      if (nameChanged) {
        hasChanges = true
        lines.push(`-- 🔄 Sütun Yeniden Adlandırma: [${orig.columnName}] → [${col.columnName}]`)
        lines.push(
          `EXEC sp_rename 'dbo.${tableName}.${orig.columnName}', '${col.columnName}', 'COLUMN';`,
        )
        lines.push('')
      }

      // Type or nullability change: ALTER COLUMN (uses new name if also renamed)
      if (typeChanged || nullChanged) {
        hasChanges = true
        const label = nameChanged
          ? `-- ✏️ Değiştirilen Sütun (yeniden adlandırıldıktan sonra): [${col.columnName}]`
          : `-- ✏️ Değiştirilen Sütun: [${col.columnName}]`
        lines.push(label)
        lines.push(`ALTER TABLE ${fullTableName}`)
        lines.push(
          `    ALTER COLUMN ${colToSqlLine({ ...col, defaultValue: '' }, false).trimStart()};`,
        )
        lines.push('')
      }
    })

  // 🔗 FK Diff: drop removed / drop+re-add modified / add new
  const fkCascadeSql = (b: CascadeBehavior) =>
    b === 'NoAction' ? 'NO ACTION' : b.replace(/([A-Z])/g, ' $1').trim().toUpperCase()

  const addFkSql = (rel: SqlTableRelation) => {
    const cname = rel.constraintName ?? `FK_${tableName}_${rel.fkColumnName}`
    lines.push(`-- 🔗 FK Ekle: [${rel.fkColumnName}] → [${rel.referencedTable}]`)
    lines.push(`ALTER TABLE ${fullTableName}`)
    lines.push(`    ADD CONSTRAINT [${cname}]`)
    lines.push(`    FOREIGN KEY ([${rel.fkColumnName}])`)
    lines.push(`    REFERENCES [dbo].[${rel.referencedTable}] ([${rel.referencedColumn || 'Id'}])`)
    lines.push(`    ON DELETE ${fkCascadeSql(rel.cascadeDelete)}`)
    lines.push(`    ON UPDATE ${fkCascadeSql(rel.cascadeUpdate)};`)
    lines.push('')
  }

  const origRelById = new Map<string, SqlTableRelation>()
  originalRelationships.forEach((r) => origRelById.set(r.id, r))
  const curRelById = new Map<string, SqlTableRelation>()
  relationships.forEach((r) => curRelById.set(r.id, r))

  // Removed FKs → DROP CONSTRAINT
  originalRelationships.forEach((orig) => {
    if (!curRelById.has(orig.id)) {
      hasChanges = true
      const cname = orig.constraintName ?? `FK_${tableName}_${orig.fkColumnName}`
      lines.push(`-- ❌ FK Kaldır: [${orig.constraintName ?? cname}]`)
      lines.push(`ALTER TABLE ${fullTableName}`)
      lines.push(`    DROP CONSTRAINT [${cname}];`)
      lines.push('')
    }
  })

  // Changed FKs → DROP old + ADD new
  relationships.forEach((rel) => {
    if (!rel.fkColumnName.trim() || !rel.referencedTable.trim()) return
    const orig = origRelById.get(rel.id)
    if (orig) {
      // Existing FK — check if anything changed
      const changed =
        orig.fkColumnName !== rel.fkColumnName ||
        orig.referencedTable !== rel.referencedTable ||
        orig.referencedColumn !== rel.referencedColumn ||
        orig.cascadeDelete !== rel.cascadeDelete ||
        orig.cascadeUpdate !== rel.cascadeUpdate
      if (changed) {
        hasChanges = true
        const cname = orig.constraintName ?? `FK_${tableName}_${orig.fkColumnName}`
        lines.push(`-- ✏️ FK Güncelle (drop + re-add): [${cname}]`)
        lines.push(`ALTER TABLE ${fullTableName}`)
        lines.push(`    DROP CONSTRAINT [${cname}];`)
        lines.push('')
        addFkSql(rel)
      }
    } else {
      // New FK
      hasChanges = true
      addFkSql(rel)
    }
  })

  if (!hasChanges) {
    lines.push(
      '/* ℹ️ Henüz değişiklik yapılmadı. Sütunları ekleyin/silin/düzeyin ya da ilişki ekleyin. */',
    )
  }

  return lines.join('\n')
}

const STEPS = ['Sütun Tasarımı', 'Entity Ayarları', 'İlişkiler', 'T-SQL Önizleme'] as const
type Step = 0 | 1 | 2 | 3

const createEmptyColumn = (): ColumnDefinition => ({
  id: crypto.randomUUID(),
  columnName: '',
  dataType: 'nvarchar',
  maxLength: '100',
  isNullable: true,
  defaultValue: '',
  description: '',
})

const DEFAULT_SETTINGS: TableSettings = {
  menuValue: '',
  menuPrefix: '',
  entityName: '',
  tableName: '',
}

// ─── Component ────────────────────────────────────────────────────────────────

const SqlTableDesignerDialog = ({
  isOpen,
  onClose,
  dataSource,
  onDeployed,
  initialTableData,
}: TableDesignerDialogProps) => {
  const { translate } = useLocalization()

  const isEditMode = !!initialTableData

  const [step, setStep] = useState<Step>(0)
  const [isDeploying, setIsDeploying] = useState(false)
  const [columns, setColumns] = useState<ColumnDefinition[]>([createEmptyColumn()])
  const [originalColumns, setOriginalColumns] = useState<ColumnDefinition[]>([])
  const [colsLoading, setColsLoading] = useState(false)
  const [settings, setSettings] = useState<TableSettings>(DEFAULT_SETTINGS)
  const [menuOptions, setMenuOptions] = useState<MenuOption[]>([])
  const [menuLoading, setMenuLoading] = useState(false)
  const [relationships, setRelationships] = useState<SqlTableRelation[]>([])
  const [originalRelationships, setOriginalRelationships] = useState<SqlTableRelation[]>([])
  const [fksLoading, setFksLoading] = useState(false)
  const [fkModalOpen, setFkModalOpen] = useState(false)
  const [editingFkId, setEditingFkId] = useState<string | null>(null)
  const [fkForm, setFkForm] = useState<Omit<SqlTableRelation, 'id'>>(EMPTY_FK)
  const [dbTables, setDbTables] = useState<{ schemaName: string; tableName: string }[]>([])
  const [targetTableColumns, setTargetTableColumns] = useState<string[]>([])  
  const [targetColsLoading, setTargetColsLoading] = useState(false)

  useEffect(() => {
    if (!isOpen) return
    setMenuLoading(true)
    const svc = new MenuService()
    svc
      .getListMainMenu()
      .then((res) => {
        const opts: MenuOption[] = (res.data || []).map((m: any) => ({
          value: m.shortName,
          label: m.displayName,
        }))
        setMenuOptions(opts)
      })
      .catch(() => {})
      .finally(() => setMenuLoading(false))

    if (dataSource) {
      sqlObjectManagerService
        .getAllObjects(dataSource)
        .then((res) => setDbTables(res.data?.tables ?? []))
        .catch(() => {})
    }

    // Edit mode: load table's existing columns + FK constraints
    if (initialTableData && dataSource) {
      setColsLoading(true)
      sqlObjectManagerService
        .getTableColumns(dataSource, initialTableData.schemaName, initialTableData.tableName)
        .then((res) => {
          const defs = (res.data ?? []).map(dbColToColumnDef)
          setColumns(defs.length > 0 ? defs : [createEmptyColumn()])
          setOriginalColumns(defs)
          setSettings((s) => ({ ...s, tableName: initialTableData.tableName }))
        })
        .catch(() => {})
        .finally(() => setColsLoading(false))

      // Derive settings from table name (e.g. "Sas_D_EntityName" → menu: "Sas", entity: "EntityName")
      const parts = initialTableData.tableName.split('_')
      const derivedMenu = parts[0] ?? ''
      const derivedEntity = parts[parts.length - 1] ?? initialTableData.tableName
      setSettings((s) => ({
        ...s,
        menuValue: derivedMenu,
        menuPrefix: derivedMenu,
        entityName: derivedEntity,
        displayName: derivedEntity,
      }))

      // Load existing FK constraints
      const fkQuery = [
        'SELECT',
        '  fk.name AS constraintName,',
        '  col.name AS fkColumnName,',
        '  ref_t.name AS referencedTable,',
        '  ref_c.name AS referencedColumn,',
        '  fk.delete_referential_action_desc AS cascadeDelete,',
        '  fk.update_referential_action_desc AS cascadeUpdate',
        'FROM sys.foreign_keys fk',
        'INNER JOIN sys.foreign_key_columns fkc ON fk.object_id = fkc.constraint_object_id',
        'INNER JOIN sys.columns col ON fkc.parent_object_id = col.object_id AND fkc.parent_column_id = col.column_id',
        'INNER JOIN sys.tables ref_t ON fkc.referenced_object_id = ref_t.object_id',
        'INNER JOIN sys.columns ref_c ON fkc.referenced_object_id = ref_c.object_id AND fkc.referenced_column_id = ref_c.column_id',
        `WHERE fk.parent_object_id = OBJECT_ID('${initialTableData.schemaName}.${initialTableData.tableName}')`,
      ].join('\n')

      const mapCascade = (v: string): CascadeBehavior => {
        if (v === 'CASCADE') return 'Cascade'
        if (v === 'SET_NULL') return 'SetNull'
        if (v === 'SET_DEFAULT') return 'Restrict'
        return 'NoAction'
      }

      setFksLoading(true)
      sqlObjectManagerService
        .executeQuery({ queryText: fkQuery, dataSourceCode: dataSource })
        .then((res) => {
          const rows: any[] = res.data?.data ?? []
          const fkDefs: SqlTableRelation[] = rows.map((r) => ({
            id: crypto.randomUUID(),
            constraintName: r.constraintName,
            relationshipType: 'OneToMany' as RelationshipType,
            fkColumnName: r.fkColumnName,
            referencedTable: r.referencedTable,
            referencedColumn: r.referencedColumn,
            cascadeDelete: mapCascade(r.cascadeDelete),
            cascadeUpdate: mapCascade(r.cascadeUpdate),
            isRequired: false,
            description: '',
          }))
          setRelationships(fkDefs)
          setOriginalRelationships(fkDefs)
        })
        .catch(() => {})
        .finally(() => setFksLoading(false))
    }
  }, [isOpen, dataSource, initialTableData])

  const generatedSql = useMemo(
    () =>
      isEditMode
        ? generateAlterTableSql(
            originalColumns,
            columns,
            settings.tableName || initialTableData?.tableName || '',
            relationships,
            originalRelationships,
          )
        : generateCreateTableSql(columns, settings, relationships),
    [isEditMode, originalColumns, columns, settings, initialTableData, relationships, originalRelationships],
  )

  // ── Column operations ──────────────────────────────────────────────────────

  const addColumn = () => setColumns((prev) => [...prev, createEmptyColumn()])

  const clearAllColumns = () => setColumns([createEmptyColumn()])

  const addFullAuditedColumns = () => {
    const existingNames = new Set(columns.map((c) => c.columnName.trim().toLowerCase()))
    const toAdd = FULL_AUDIT_COLUMNS.filter(
      (c) => !existingNames.has(c.columnName.toLowerCase()),
    )
    setColumns((prev) => {
      const nonEmpty = prev.filter((c) => c.columnName.trim() !== '')
      return [...nonEmpty, ...toAdd.map((c) => ({ ...c })), createEmptyColumn()]
    })
  }

  const addMultiTenantColumns = () => {
    const existingNames = new Set(columns.map((c) => c.columnName.trim().toLowerCase()))
    if (!existingNames.has(TENANT_COLUMN.columnName.toLowerCase())) {
      setColumns((prev) => {
        const nonEmpty = prev.filter((c) => c.columnName.trim() !== '')
        return [...nonEmpty, { ...TENANT_COLUMN }, createEmptyColumn()]
      })
    }
  }

  const removeColumn = (id: string) => setColumns((prev) => prev.filter((c) => c.id !== id))

  const moveColumn = (id: string, direction: 'up' | 'down') => {
    setColumns((prev) => {
      const idx = prev.findIndex((c) => c.id === id)
      if (idx < 0) return prev
      const next = [...prev]
      const swap = direction === 'up' ? idx - 1 : idx + 1
      if (swap < 0 || swap >= next.length) return prev
      ;[next[idx], next[swap]] = [next[swap], next[idx]]
      return next
    })
  }

  const updateColumn = useCallback(
    <K extends keyof ColumnDefinition>(id: string, field: K, value: ColumnDefinition[K]) => {
      setColumns((prev) => prev.map((c) => (c.id === id ? { ...c, [field]: value } : c)))
    },
    [],
  )

  // ── Settings helpers ───────────────────────────────────────────────────────

  const buildTableName = (prefix: string, entity: string) =>
    prefix && entity ? `${prefix}_D_${entity}` : ''

  const onMenuChange = (value: string) => {
    const opt = menuOptions.find((o) => o.value === value)
    const prefix = opt?.value ?? ''
    setSettings((s) => ({
      ...s,
      menuValue: value,
      menuPrefix: prefix,
      tableName: buildTableName(prefix, s.entityName),
    }))
  }

  // Strip spaces and special chars — only alphanumeric + underscore allowed
  const onEntityNameChange = (value: string) => {
    const sanitized = value.replace(/[^A-Za-z0-9_]/g, '')
    setSettings((s) => ({
      ...s,
      entityName: sanitized,
      tableName: buildTableName(s.menuPrefix, sanitized),
      displayName: sanitized, // always mirrors entity name
    }))
  }

  // ── FK Relationship handlers ───────────────────────────────────────────────

  const loadTargetColumns = (tableName: string) => {
    if (!tableName || !dataSource) {
      setTargetTableColumns([])
      return
    }
    const tbl = dbTables.find((t) => t.tableName === tableName)
    if (!tbl) return
    setTargetColsLoading(true)
    sqlObjectManagerService
      .getTableColumns(dataSource, tbl.schemaName, tbl.tableName)
      .then((res) => setTargetTableColumns((res.data ?? []).map((c) => c.columnName)))
      .catch(() => setTargetTableColumns([]))
      .finally(() => setTargetColsLoading(false))
  }

  const openAddFk = () => {
    setEditingFkId(null)
    setFkForm(EMPTY_FK)
    setTargetTableColumns([])
    setFkModalOpen(true)
  }

  const openEditFk = (rel: SqlTableRelation) => {
    setEditingFkId(rel.id)
    const { id: _id, ...rest } = rel
    setFkForm(rest)
    loadTargetColumns(rest.referencedTable)
    setFkModalOpen(true)
  }

  const saveFk = () => {
    if (!fkForm.fkColumnName.trim() || !fkForm.referencedTable.trim()) return
    if (editingFkId) {
      setRelationships((prev) =>
        prev.map((r) => (r.id === editingFkId ? { ...fkForm, id: editingFkId } : r)),
      )
    } else {
      setRelationships((prev) => [...prev, { ...fkForm, id: crypto.randomUUID() }])
    }
    setFkModalOpen(false)
  }

  const deleteFk = (id: string) => {
    setRelationships((prev) => prev.filter((r) => r.id !== id))
  }

  // ── Navigation ─────────────────────────────────────────────────────────────

  // Compute duplicate column names (lowercased)
  const duplicateColumnNames = useMemo(() => {
    const names = columns.map((c) => c.columnName.trim().toLowerCase()).filter(Boolean)
    return new Set(names.filter((n, i) => names.indexOf(n) !== i))
  }, [columns])

  const canGoNext = (): boolean => {
    if (step === 0) {
      const hasNamed = columns.some((c) => c.columnName.trim().length > 0)
      return hasNamed && duplicateColumnNames.size === 0
    }
    if (step === 1) {
      if (isEditMode) return true // table name is locked in edit mode
      const baseOk =
        !!settings.tableName.trim() && !!settings.entityName.trim() && !!settings.menuValue
      if (!baseOk) return false
      return columns.some((c) => c.columnName.trim().toLowerCase() === 'id')
    }
    return true
  }

  const handleNext = () => {
    if (step < 3) setStep((s) => (s + 1) as Step)
  }
  const handleBack = () => {
    if (step > 0) setStep((s) => (s - 1) as Step)
  }

  // ── Deploy ─────────────────────────────────────────────────────────────────

  const handleDeploy = async () => {
    if (!dataSource) {
      toast.push(
        <Notification type="warning" title="Uyari">
          Lutfen once bir veri kaynagi secin.
        </Notification>,
        { placement: 'top-center' },
      )
      return
    }
    setIsDeploying(true)
    try {
      const result = await sqlObjectManagerService.executeQuery({
        queryText: generatedSql,
        dataSourceCode: dataSource,
      })
      if (result.data.success) {
        const deployedTable = settings.tableName || initialTableData?.tableName || ''
        toast.push(
          <Notification type="success" title="Basarili">
            Tablo basariyla {isEditMode ? 'güncellendi' : 'oluşturuldu'}: [dbo].[{deployedTable}]
          </Notification>,
          { placement: 'top-center' },
        )
        onDeployed?.()
        handleClose()
      } else {
        toast.push(
          <Notification type="danger" title="Hata">
            {result.data.message || 'Tablo olusturulamadi.'}
          </Notification>,
          { placement: 'top-center' },
        )
      }
    } catch (error: any) {
      toast.push(
        <Notification type="danger" title="Hata">
          {error.response?.data?.error?.message || 'Tablo deploy edilemedi.'}
        </Notification>,
        { placement: 'top-center' },
      )
    } finally {
      setIsDeploying(false)
    }
  }

  const handleClose = () => {
    setStep(0)
    setColumns([createEmptyColumn()])
    setOriginalColumns([])
    setSettings(DEFAULT_SETTINGS)
    setRelationships([])
    setOriginalRelationships([])
    setDbTables([])
    setTargetTableColumns([])
    onClose()
  }

  // ── Step Indicator ─────────────────────────────────────────────────────────

  const STEP_LABELS = ['Sütun Tasarımı', 'Entity Ayarları', 'İlişkiler', 'T-SQL Önizleme']

  const renderStepIndicator = () => (
    <div className="flex items-center justify-between mb-2">
      {STEP_LABELS.map((label, i) => {
        const isDone = i < step
        const isActive = i === step
        return (
          <div key={i} className="flex items-center flex-1">
            <div className="flex items-center gap-2">
              <div
                className={`w-7 h-7 rounded-full flex items-center justify-center text-xs font-bold transition-colors
                  ${isDone ? 'bg-green-500 text-white' : isActive ? 'bg-blue-600 text-white' : 'bg-gray-200 text-gray-500 dark:bg-gray-700 dark:text-gray-400'}`}
              >
                {isDone ? <FaCheck /> : i + 1}
              </div>
              <span
                className={`text-sm font-medium whitespace-nowrap ${isActive ? 'text-blue-600 dark:text-blue-400' : 'text-gray-500'}`}
              >
                {label}
              </span>
            </div>
            {i < STEP_LABELS.length - 1 && (
              <div className="flex-1 mx-3 h-px bg-gray-200 dark:bg-gray-700" />
            )}
          </div>
        )
      })}
    </div>
  )

  // ── Step 0: Column Designer ────────────────────────────────────────────────

  const renderColumnDesigner = () => (
    <div className="flex flex-col">
      {colsLoading && (
        <div className="flex items-center justify-center py-12 text-gray-500">
          <span className="animate-spin mr-2">&#9696;</span> Tablo sütunları yükleniyor...
        </div>
      )}
      {!colsLoading && (
      <>
      <div className="flex items-center justify-between py-2">
        <div className="flex items-center gap-2">
          <Button size="xs" variant="solid" color="blue-600" onClick={addFullAuditedColumns}>
            Full Audited Entity Sütunları Ekle
          </Button>
          <Button size="xs" variant="solid" color="green-600" onClick={addMultiTenantColumns}>
            MultiTenant Sütunları Ekle
          </Button>
        </div>
        <div className="flex items-center gap-2">
          <Button size="xs" variant="solid" color="red-600" icon={<FaTrash />} onClick={clearAllColumns}>
            Tüm Sütunları Sil
          </Button>
          <Button size="xs" variant="solid" color="blue-600" icon={<FaPlus />} onClick={addColumn}>
            Sütun Ekle
          </Button>
        </div>
      </div>

      {/* Header row */}
      <div className="grid grid-cols-12 gap-1 px-1 py-1 bg-gray-50 dark:bg-gray-800 rounded text-xs font-semibold text-gray-600 dark:text-gray-300">
        <div className="col-span-3">Sutun Adi *</div>
        <div className="col-span-3">Veri Tipi *</div>
        <div className="col-span-1 text-center">Max</div>
        <div className="col-span-1 text-center">Null</div>
        <div className="col-span-2">Varsayilan</div>
        <div className="col-span-1">Not</div>
        <div className="col-span-1 text-center">Islem</div>
      </div>

      {/* Editable column rows */}
      {duplicateColumnNames.size > 0 && (
        <div className="px-1 py-1.5 bg-red-50 dark:bg-red-900/20 border border-red-200 dark:border-red-800 rounded text-xs text-red-600 dark:text-red-400">
          ⚠️ Aynı isimde sütun tanımlanamaz:{' '}
          {[...duplicateColumnNames].map((n) => (
            <code key={n} className="bg-red-100 dark:bg-red-900/40 px-1 rounded mr-1">
              {n}
            </code>
          ))}
        </div>
      )}

      <div className="flex flex-col gap-1 max-h-80 overflow-y-auto pr-1">
        {columns.map((col, idx) => {
          const isDuplicate =
            col.columnName.trim() !== '' &&
            duplicateColumnNames.has(col.columnName.trim().toLowerCase())
          const isNewRow =
            isEditMode &&
            !originalColumns.some((o) => o.id === col.id)

          const origRow = isEditMode ? originalColumns.find((o) => o.id === col.id) : undefined
          const isRenamedRow =
            isEditMode &&
            !!origRow &&
            origRow.columnName.trim().toLowerCase() !== col.columnName.trim().toLowerCase()
          const isModifiedRow =
            isEditMode &&
            !!origRow &&
            !isNewRow &&
            (origRow.dataType !== col.dataType ||
              origRow.maxLength !== col.maxLength ||
              origRow.isNullable !== col.isNullable)

          const rowBg = isDuplicate
            ? 'outline outline-1 outline-red-400'
            : isNewRow
            ? 'bg-green-50 dark:bg-green-900/20 outline outline-1 outline-green-400'
            : isRenamedRow && isModifiedRow
            ? 'bg-purple-50 dark:bg-purple-900/20 outline outline-1 outline-purple-400'
            : isRenamedRow
            ? 'bg-blue-50 dark:bg-blue-900/20 outline outline-1 outline-blue-400'
            : isModifiedRow
            ? 'bg-yellow-50 dark:bg-yellow-900/20 outline outline-1 outline-yellow-400'
            : ''

          return (
          <div
            key={col.id}
            className={`grid grid-cols-12 gap-2 bg-white dark:bg-gray-800 rounded items-center ${rowBg}`}
          >
            <div className="col-span-3">
              <input
                type="text"
                className={`w-full px-2 py-1 text-sm border rounded dark:bg-gray-700 dark:border-gray-600 dark:text-white ${
                  isDuplicate ? 'border-red-400' : ''
                }`}
                placeholder="SutunAdi"
                value={col.columnName}
                onChange={(e) => updateColumn(col.id, 'columnName', e.target.value)}
              />
            </div>
            <div className="col-span-3">
              <select
                className="w-full px-2 py-1 text-sm border rounded dark:bg-gray-700 dark:border-gray-600 dark:text-white"
                value={col.dataType}
                onChange={(e) => {
                  const dt = e.target.value as SqlDataType
                  updateColumn(col.id, 'dataType', dt)
                  if (dt !== 'nvarchar') updateColumn(col.id, 'maxLength', '')
                  else if (!col.maxLength) updateColumn(col.id, 'maxLength', '100')
                }}
              >
                {DATA_TYPES.map((t) => (
                  <option key={t.value} value={t.value}>
                    {t.label}
                  </option>
                ))}
              </select>
            </div>
            <div className="col-span-1">
              <input
                type="number"
                className="w-full px-2 py-1 text-sm border rounded dark:bg-gray-700 dark:border-gray-600 dark:text-white text-center"
                placeholder="-"
                value={col.maxLength}
                disabled={col.dataType !== 'nvarchar'}
                onChange={(e) => updateColumn(col.id, 'maxLength', e.target.value)}
              />
            </div>
            <div className="col-span-1 flex justify-center">
              <Checkbox
                checked={col.isNullable}
                onChange={(checked) => updateColumn(col.id, 'isNullable', checked as boolean)}
              />
            </div>
            <div className="col-span-2">
              <input
                type="text"
                className="w-full px-2 py-1 text-sm border rounded dark:bg-gray-700 dark:border-gray-600 dark:text-white"
                placeholder="Varsayilan"
                value={col.defaultValue}
                onChange={(e) => updateColumn(col.id, 'defaultValue', e.target.value)}
              />
            </div>
            <div className="col-span-1">
              <input
                type="text"
                className="w-full px-2 py-1 text-xs border rounded dark:bg-gray-700 dark:border-gray-600 dark:text-white"
                placeholder="Not"
                value={col.description}
                onChange={(e) => updateColumn(col.id, 'description', e.target.value)}
              />
            </div>
            <div className="col-span-1 flex items-center justify-center gap-1">
              <button
                onClick={() => moveColumn(col.id, 'up')}
                disabled={idx === 0}
                className="p-1 rounded hover:bg-gray-100 dark:hover:bg-gray-700 disabled:opacity-30 text-gray-500"
                title="Yukari tasi"
              >
                <FaArrowUp className="text-xs" />
              </button>
              <button
                onClick={() => moveColumn(col.id, 'down')}
                disabled={idx === columns.length - 1}
                className="p-1 rounded hover:bg-gray-100 dark:hover:bg-gray-700 disabled:opacity-30 text-gray-500"
                title="Asagi tasi"
              >
                <FaArrowDown className="text-xs" />
              </button>
              <button
                onClick={() => removeColumn(col.id)}
                className="p-1 rounded hover:bg-red-50 dark:hover:bg-red-900/30 text-red-500"
                title="Sil"
              >
                <FaTrash className="text-xs" />
              </button>
            </div>
          </div>
          )
        })}
      </div>

      {/* Id warning */}
      {!isEditMode &&
        !columns.some((c) => c.columnName.trim().toLowerCase() === 'id') && (
          <div className="px-2 py-1.5 bg-orange-50 dark:bg-orange-900/20 border border-orange-300 dark:border-orange-700 rounded text-xs text-orange-700 dark:text-orange-300">
            ⚠️ <strong>Full Audited Entity</strong> seçilmedi. Tablonun birincil anahtarı için{' '}
            <code className="bg-orange-100 dark:bg-orange-900/40 px-1 rounded">Id</code> sütununu
            elle eklemeniz gerekmektedir.
          </div>
        )}
      </>
      )}
    </div>
  )

  // ── Step 1: Entity Settings ────────────────────────────────────────────────

  const renderEntitySettings = () => (
    <div className="flex flex-col gap-2">
      <div className="grid grid-cols-2 gap-2">
        {/* Menu Name */}
        <div className="col-span-2">
          <label className="block text-sm font-medium mb-1">
            Menu Name <span className="text-red-500">*</span>
          </label>
          <select
            className="w-full px-3 py-2 text-sm border rounded dark:bg-gray-700 dark:border-gray-600 dark:text-white"
            value={settings.menuValue}
            disabled={menuLoading || isEditMode} // Menu cannot be changed in edit mode (as it determines the table name)
            onChange={(e) => onMenuChange(e.target.value)}
          >
            <option value=""></option>
            {menuOptions.map((opt) => (
              <option key={opt.value} value={opt.value}>
                {opt.label} ({opt.value})
              </option>
            ))}
          </select>
          {menuLoading && <p className="text-xs text-gray-400 mt-1">Yukleniyor...</p>}
        </div>

        {/* Entity Name */}
        <div>
          <label className="block text-sm font-medium mb-1">
            Entity Name <span className="text-red-500">*</span>
          </label>
          <input
            type="text"
            disabled={isEditMode} // Entity name (and thus table name) cannot be changed in edit mode
            className="w-full px-3 py-2 text-sm border rounded dark:bg-gray-700 dark:border-gray-600 dark:text-white"
            value={settings.entityName}
            onChange={(e) => onEntityNameChange(e.target.value)}
            placeholder="e.g. Product, User, Order"
          />
        </div>

        {/* Table Name (readonly, auto-generated) */}
        <div>
          <label className="block text-sm font-medium mb-1">Table Name</label>
          <input
            type="text"
            readOnly
            className="w-full px-3 py-2 text-sm border rounded bg-gray-50 dark:bg-gray-800 dark:border-gray-600 dark:text-gray-300 cursor-not-allowed"
            value={isEditMode ? (initialTableData?.tableName ?? '') : settings.tableName}
            placeholder="Menu ve Entity Name seçince otomatik oluşur"
          />
        </div>
      </div>


      {/* Warning: no Id column */}
      {!isEditMode &&
        !columns.some((c) => c.columnName.trim().toLowerCase() === 'id') && (
          <div className="px-3 py-2 bg-red-50 dark:bg-red-900/20 border border-red-300 dark:border-red-700 rounded text-xs text-red-700 dark:text-red-300">
            ⛔ <strong>Full Audited Entity</strong> seçili değil. Geri dönüp{' '}
            <code className="bg-red-100 dark:bg-red-900/40 px-1 rounded">Id</code> sütununu{' '}
            <code className="bg-red-100 dark:bg-red-900/40 px-1 rounded">uniqueidentifier</code>{' '}
            tipinde manuel olarak eklemelisiniz.
          </div>
        )}
    </div>
  )

  // ── Step 2: Relationships ─────────────────────────────────────────────────

  const renderRelationships = () => (
    <div className="space-y-3">
      {/* Loading indicator for edit mode */}
      {fksLoading && (
        <div className="flex items-center justify-center py-10 text-gray-500 text-sm gap-2">
          <span className="animate-spin">&#9696;</span> Mevcut FK kısıtlamaları yükleniyor...
        </div>
      )}
      {!fksLoading && <>
      {/* Header */}
      <div className="flex items-center justify-between">
        <span className="text-xs text-gray-500">
          {relationships.length === 0 ? 'İlişki tanımlanmamış' : `${relationships.length} ilişki`}
        </span>
        <button
          onClick={openAddFk}
          className="flex items-center gap-1 px-3 py-1.5 bg-indigo-600 hover:bg-indigo-700 text-white text-xs rounded-lg transition-colors"
        >
          <FaPlus className="w-2.5 h-2.5" /> İlişki Ekle
        </button>
      </div>

      {/* Empty state */}
      {relationships.length === 0 && (
        <div className="py-8 text-center border-2 border-dashed border-gray-200 dark:border-gray-700 rounded-xl bg-gray-50 dark:bg-gray-800/50">
          <FaLink className="text-3xl mx-auto text-gray-300 dark:text-gray-600 mb-2" />
          <p className="text-sm text-gray-500">Bu tablo için henüz ilişki tanımlanmamış</p>
          <p className="text-xs text-gray-400 mt-1">Bu adım isteğe bağlıdır, atlayabilirsiniz</p>
        </div>
      )}

      {/* Relationship cards */}
      <div className="space-y-2 max-h-72 overflow-y-auto pr-1">
        {relationships.map((rel) => (
          <div
            key={rel.id}
            className="border border-slate-200 dark:border-gray-700 rounded-xl px-4 py-3 flex items-start gap-3 bg-white dark:bg-gray-800"
          >
            <div className="p-2 rounded-lg mt-0.5 flex-shrink-0 bg-indigo-50 dark:bg-indigo-900/20 text-indigo-600 dark:text-indigo-400">
              <FaLink className="w-3 h-3" />
            </div>
            <div className="flex-1 min-w-0">
              <div className="flex items-center gap-2 flex-wrap">
                <code className="text-sm font-semibold text-slate-900 dark:text-white">
                  [{rel.fkColumnName}]
                </code>
                <FaArrowRight className="w-3 h-3 text-gray-400 flex-shrink-0" />
                <code className="text-sm font-semibold text-slate-900 dark:text-white">
                  [dbo].[{rel.referencedTable}].[{rel.referencedColumn || 'Id'}]
                </code>
                <span className="text-xs px-2 py-0.5 rounded-full bg-indigo-100 dark:bg-indigo-900/30 text-indigo-700 dark:text-indigo-300 font-medium">
                  {REL_TYPES.find((t) => t.value === rel.relationshipType)?.label}
                </span>
              </div>
              <div className="flex items-center gap-3 mt-1 text-xs text-gray-500 flex-wrap">
                <span>ON DELETE: <strong>{rel.cascadeDelete}</strong></span>
                <span>ON UPDATE: <strong>{rel.cascadeUpdate}</strong></span>
                {rel.isRequired && (
                  <span className="text-orange-600 dark:text-orange-400">Zorunlu</span>
                )}
                {rel.description && (
                  <span className="text-gray-400 italic">{rel.description}</span>
                )}
              </div>
            </div>
            <div className="flex items-center gap-1 flex-shrink-0">
              <button
                onClick={() => openEditFk(rel)}
                title="Düzenle"
                className="p-1.5 text-gray-400 hover:text-indigo-600 hover:bg-indigo-50 dark:hover:bg-indigo-900/20 rounded transition-colors"
              >
                <FaEdit className="w-3.5 h-3.5" />
              </button>
              <button
                onClick={() => deleteFk(rel.id)}
                title="Sil"
                className="p-1.5 text-gray-400 hover:text-red-600 hover:bg-red-50 dark:hover:bg-red-900/20 rounded transition-colors"
              >
                <FaTrash className="w-3.5 h-3.5" />
              </button>
            </div>
          </div>
        ))}
      </div>
      </>}

      {/* FK Add/Edit Modal */}
      {fkModalOpen && createPortal(
        <div className="fixed inset-0 z-50 flex items-center justify-center p-4 bg-black/50 backdrop-blur-sm">
          <div className="bg-white dark:bg-gray-800 rounded-2xl shadow-2xl w-full max-w-lg flex flex-col">
            {/* Modal Header */}
            <div className="flex items-center justify-between px-6 py-4 border-b border-gray-200 dark:border-gray-700">
              <h2 className="text-base font-bold text-gray-900 dark:text-white">
                {editingFkId ? 'İlişkiyi Düzenle' : 'Yeni İlişki Ekle'}
              </h2>
              <button
                onClick={() => setFkModalOpen(false)}
                className="p-2 text-gray-400 hover:text-gray-600 rounded-lg transition-colors"
              >
                <FaTimes className="w-4 h-4" />
              </button>
            </div>

            {/* Modal Body */}
            <div className="flex-1 overflow-y-auto px-6 py-4 space-y-4">
              {/* Relationship type */}
              <div>
                <label className="block text-xs font-semibold text-gray-700 dark:text-gray-300 mb-2">
                  İlişki Tipi
                </label>
                <div className="flex gap-2">
                  {REL_TYPES.map((t) => (
                    <button
                      key={t.value}
                      type="button"
                      onClick={() => setFkForm((f) => ({ ...f, relationshipType: t.value }))}
                      className={`flex-1 py-2 px-3 rounded-lg border text-sm font-medium transition-all ${
                        fkForm.relationshipType === t.value
                          ? 'bg-indigo-600 border-indigo-600 text-white'
                          : 'bg-white dark:bg-gray-700 border-gray-200 dark:border-gray-600 text-gray-600 dark:text-gray-300 hover:border-indigo-300'
                      }`}
                    >
                      {t.label}
                      <span className="block text-xs opacity-70">{t.desc}</span>
                    </button>
                  ))}
                </div>
              </div>

              {/* FK column / Referenced table & column */}
              <div className="grid grid-cols-2 gap-3">
                <div>
                  <label className="block text-xs font-semibold text-gray-700 dark:text-gray-300 mb-1.5">
                    Bu Tablodaki FK Sütunu *
                  </label>
                  <select
                    value={fkForm.fkColumnName}
                    onChange={(e) => setFkForm((f) => ({ ...f, fkColumnName: e.target.value }))}
                    className="w-full px-3 py-2 border border-gray-300 dark:border-gray-600 rounded-lg text-sm dark:bg-gray-700 dark:text-white focus:ring-2 focus:ring-indigo-500"
                  >
                    <option value="">— Seçiniz —</option>
                    {columns
                      .filter((c) => c.columnName.trim())
                      .map((c) => (
                        <option key={c.id} value={c.columnName}>
                          {c.columnName}
                        </option>
                      ))}
                  </select>
                </div>
                <div>
                  <label className="block text-xs font-semibold text-gray-700 dark:text-gray-300 mb-1.5">
                    Hedef Tablo *
                  </label>
                  <select
                    value={fkForm.referencedTable}
                    onChange={(e) => {
                      const val = e.target.value
                      setFkForm((f) => ({ ...f, referencedTable: val, referencedColumn: '' }))
                      loadTargetColumns(val)
                    }}
                    className="w-full px-3 py-2 border border-gray-300 dark:border-gray-600 rounded-lg text-sm dark:bg-gray-700 dark:text-white focus:ring-2 focus:ring-indigo-500"
                  >
                    <option value="">— Seçiniz —</option>
                    {dbTables.map((t) => (
                      <option key={`${t.schemaName}.${t.tableName}`} value={t.tableName}>
                        {t.tableName}
                      </option>
                    ))}
                  </select>
                </div>
              </div>

              <div>
                <label className="block text-xs font-semibold text-gray-700 dark:text-gray-300 mb-1.5">
                  Hedef Sütun (PK){targetColsLoading ? ' — Yükleniyor...' : ''}
                </label>
                <select
                  value={fkForm.referencedColumn}
                  onChange={(e) => setFkForm((f) => ({ ...f, referencedColumn: e.target.value }))}
                  disabled={targetColsLoading || targetTableColumns.length === 0}
                  className="w-full px-3 py-2 border border-gray-300 dark:border-gray-600 rounded-lg text-sm dark:bg-gray-700 dark:text-white focus:ring-2 focus:ring-indigo-500 disabled:opacity-60"
                >
                  <option value="">— Önce hedef tablo seçin —</option>
                  {targetTableColumns.map((col) => (
                    <option key={col} value={col}>
                      {col}
                    </option>
                  ))}
                </select>
              </div>

              {/* Cascade */}
              <div className="grid grid-cols-2 gap-3">
                <div>
                  <label className="block text-xs font-semibold text-gray-700 dark:text-gray-300 mb-1.5">
                    Cascade Delete
                  </label>
                  <select
                    value={fkForm.cascadeDelete}
                    onChange={(e) =>
                      setFkForm((f) => ({ ...f, cascadeDelete: e.target.value as CascadeBehavior }))
                    }
                    className="w-full px-3 py-2 border border-gray-300 dark:border-gray-600 rounded-lg text-sm dark:bg-gray-700 dark:text-white focus:ring-2 focus:ring-indigo-500"
                  >
                    {CASCADE_OPTIONS.map((o) => (
                      <option key={o.value} value={o.value}>{o.label}</option>
                    ))}
                  </select>
                </div>
                <div>
                  <label className="block text-xs font-semibold text-gray-700 dark:text-gray-300 mb-1.5">
                    Cascade Update
                  </label>
                  <select
                    value={fkForm.cascadeUpdate}
                    onChange={(e) =>
                      setFkForm((f) => ({ ...f, cascadeUpdate: e.target.value as CascadeBehavior }))
                    }
                    className="w-full px-3 py-2 border border-gray-300 dark:border-gray-600 rounded-lg text-sm dark:bg-gray-700 dark:text-white focus:ring-2 focus:ring-indigo-500"
                  >
                    {CASCADE_OPTIONS.map((o) => (
                      <option key={o.value} value={o.value}>{o.label}</option>
                    ))}
                  </select>
                </div>
              </div>

              {/* Options */}
              <div className="flex items-center gap-6">
                <label className="flex items-center gap-2 cursor-pointer">
                  <input
                    type="checkbox"
                    checked={fkForm.isRequired}
                    onChange={(e) => setFkForm((f) => ({ ...f, isRequired: e.target.checked }))}
                    className="w-4 h-4 text-indigo-600 rounded"
                  />
                  <span className="text-sm text-gray-700 dark:text-gray-300">Zorunlu</span>
                </label>
              </div>

              {/* Description */}
              <div>
                <label className="block text-xs font-semibold text-gray-700 dark:text-gray-300 mb-1.5">
                  Açıklama
                </label>
                <textarea
                  value={fkForm.description}
                  onChange={(e) => setFkForm((f) => ({ ...f, description: e.target.value }))}
                  rows={2}
                  placeholder="İsteğe bağlı açıklama..."
                  className="w-full px-3 py-2 border border-gray-300 dark:border-gray-600 rounded-lg text-sm dark:bg-gray-700 dark:text-white focus:ring-2 focus:ring-indigo-500 resize-none"
                />
              </div>
            </div>

            {/* Modal Footer */}
            <div className="flex items-center justify-end gap-2 px-6 py-4 border-t border-gray-200 dark:border-gray-700 bg-gray-50 dark:bg-gray-800/50 rounded-b-2xl">
              <button
                onClick={() => setFkModalOpen(false)}
                className="px-4 py-2 text-sm text-gray-600 dark:text-gray-300 hover:bg-gray-100 dark:hover:bg-gray-700 rounded-lg transition-colors"
              >
                İptal
              </button>
              <button
                onClick={saveFk}
                disabled={!fkForm.fkColumnName.trim() || !fkForm.referencedTable.trim()}
                className="px-4 py-2 text-sm bg-indigo-600 hover:bg-indigo-700 disabled:opacity-50 text-white rounded-lg transition-colors"
              >
                Kaydet
              </button>
            </div>
          </div>
        </div>,
        document.body
      )}
    </div>
  )

  // ── Step 3: T-SQL Preview ──────────────────────────────────────────────────

  const renderSqlPreview = () => (
    <div className="flex flex-col gap-3">
      <div className="flex items-center justify-between">
        <p className="text-sm text-gray-600 dark:text-gray-400">
          Olusturulan T-SQL kodu. <strong>Deploy Et</strong> ile veritabanina uygulayin.
        </p>
        <button
          className="text-xs text-blue-500 hover:underline"
          onClick={() => navigator.clipboard.writeText(generatedSql)}
        >
          Kopyala
        </button>
      </div>
      <pre className="bg-gray-900 text-green-300 rounded-lg p-4 text-xs overflow-auto max-h-96 leading-relaxed whitespace-pre">
        {generatedSql}
      </pre>
    </div>
  )

  // ── Render ─────────────────────────────────────────────────────────────────

  return (
    <Dialog isOpen={isOpen} onClose={handleClose} onRequestClose={handleClose} width={900}>
      <div className="flex flex-col gap-2">
        {/* Header */}
        <div className="flex items-center gap-3 border-b pb-3">
          <FaTable className="text-2xl text-blue-500" />
          <div>
            <h5 className="font-bold">
              {isEditMode
                ? `Tablo Düzenle — ${initialTableData?.tableName}`
                : 'Tablo Tasarımcısı'}
            </h5>
            <p className="text-xs text-gray-500">
              {isEditMode
                ? 'Mevcut sütunları düzenleyin, yeni ekleyin veya ilişki tanımlayın — ALTER TABLE SQL üretilir'
                : 'Sütunları tanımlayın, ayarları yapın ve T-SQL ile deploy edin'}
            </p>
          </div>
        </div>

        {/* Steps */}
        {renderStepIndicator()}

        {/* Content */}
        <div className="min-h-[420px]">
          {step === 0 && renderColumnDesigner()}
          {step === 1 && renderEntitySettings()}
          {step === 2 && renderRelationships()}
          {step === 3 && renderSqlPreview()}
        </div>

        {/* Footer */}
        <div className="flex justify-between items-center border-t pt-3 mt-1">
          <Button variant="plain" onClick={handleClose}>
            Iptal
          </Button>
          <div className="flex items-center gap-2">
            {step > 0 && (
              <Button variant="default" onClick={handleBack}>
                Geri
              </Button>
            )}
            {step < 3 ? (
              <Button variant="solid" color="blue-600" onClick={handleNext} disabled={!canGoNext()}>
                İleri
              </Button>
            ) : (
              <Button
                variant="solid"
                color="green-600"
                icon={<FaCloudUploadAlt />}
                onClick={handleDeploy}
                loading={isDeploying}
                disabled={!dataSource || isDeploying || (isEditMode && generatedSql.includes('Henüz değişiklik yapılmadı'))}
              >
                Deploy Et
              </Button>
            )}
          </div>
        </div>
      </div>
    </Dialog>
  )
}

export default SqlTableDesignerDialog