import {
  getDesignerCollectionProperty,
  getDesignerTabSlotValue,
  isDesignerDateComponent,
  isDesignerDateProperty,
  isDesignerOptionComponent,
  normalizeDesignerKeyList,
  DESIGNER_DROPDOWN_PLACEHOLDER,
  type DesignerDocument,
  type DesignerNode,
} from './types'

const safeIdentifier = (value: string) => {
  const cleaned = value.replace(/[^A-Za-z0-9_$]/g, '_')
  return /^[A-Za-z_$]/.test(cleaned) ? cleaned : `Component_${cleaned}`
}

const staticValueExpression = (value: unknown): string => {
  if (typeof value === 'string') {
    return value.startsWith('::') ? `translate(${JSON.stringify(value)})` : JSON.stringify(value)
  }
  if (Array.isArray(value)) return `[${value.map(staticValueExpression).join(', ')}]`
  if (value && typeof value === 'object') {
    return `{ ${Object.entries(value)
      .map(([key, item]) => `${JSON.stringify(key)}: ${staticValueExpression(item)}`)
      .join(', ')} }`
  }
  if (value === undefined) return 'undefined'
  return JSON.stringify(value)
}

const serializeValue = (value: unknown) => `{${staticValueExpression(value)}}`

const bindingExpression = (node: DesignerNode, propertyName: string, itemVariable?: string) => {
  const binding = node.bindings?.[propertyName]
  if (!binding?.sourceId) return ''
  const path = binding.path.trim()
  if (itemVariable && (path === '$item' || path.startsWith('$item.'))) {
    return `getByPath(${itemVariable}, ${JSON.stringify(path === '$item' ? '' : path.slice(6))})`
  }
  return `getByPath(data_${safeIdentifier(binding.sourceId)}, ${JSON.stringify(binding.path || '')})`
}

interface RuntimeStateSpec {
  propertyName: string
  eventName: string
  stateName: string
  setterName: string
  initialValue: unknown
}

const getRuntimeStateSpec = (node: DesignerNode): RuntimeStateSpec | null => {
  const configured: Record<string, { propertyName: string; eventName: string }> = {
    AutoComplete: { propertyName: 'value', eventName: 'onInputChange' },
    Dropdown: { propertyName: 'activeKey', eventName: 'onSelect' },
    Input: { propertyName: 'value', eventName: 'onChange' },
    ImageViewer: { propertyName: 'activeIndex', eventName: 'onIndexChange' },
    Menu: { propertyName: 'defaultActiveKeys', eventName: 'onSelect' },
    Pagination: { propertyName: 'currentPage', eventName: 'onChange' },
    'Radio.Group': { propertyName: 'value', eventName: 'onChange' },
    Select: { propertyName: 'value', eventName: 'onChange' },
    Steps: { propertyName: 'current', eventName: 'onChange' },
    Tabs: { propertyName: 'value', eventName: 'onChange' },
    Upload: { propertyName: 'fileList', eventName: 'onChange' },
  }
  const fallback =
    'checked' in node.props
      ? { propertyName: 'checked', eventName: 'onChange' }
      : 'value' in node.props
        ? { propertyName: 'value', eventName: 'onChange' }
        : null
  const state = configured[node.type] || fallback
  if (!state || node.bindings?.[state.propertyName]?.sourceId) return null

  let initialValue = node.props[state.propertyName]
  if (node.type === 'Select') {
    const options = Array.isArray(node.props.options) ? node.props.options : []
    initialValue = node.props.isMulti
      ? options.filter(
          (option) =>
            option &&
            typeof option === 'object' &&
            !Array.isArray(option) &&
            Array.isArray(node.props.value) &&
            node.props.value.includes((option as Record<string, unknown>).value),
        )
      : options.find(
          (option) =>
            option &&
            typeof option === 'object' &&
            !Array.isArray(option) &&
            (option as Record<string, unknown>).value === node.props.value,
        ) || null
  } else if (node.type === 'Menu') {
    initialValue = normalizeDesignerKeyList(initialValue)
  } else if (node.type === 'Tabs') {
    initialValue = initialValue === undefined || initialValue === null ? '' : String(initialValue)
  } else if (node.type === 'Pagination') {
    initialValue = Number(initialValue) || 1
  } else if (initialValue === undefined) {
    initialValue = state.propertyName === 'checked' ? false : ''
  }

  const identifier = safeIdentifier(node.id)
  return {
    ...state,
    stateName: `runtime_${identifier}_${safeIdentifier(state.propertyName)}`,
    setterName: `setRuntime_${identifier}_${safeIdentifier(state.propertyName)}`,
    initialValue,
  }
}

const isOptionCollectionProperty = (node: DesignerNode, propertyName: string) =>
  isDesignerOptionComponent(node.type) && propertyName === getDesignerCollectionProperty(node.type)

/**
 * Options expression for a data component: the endpoint binding mapped through
 * `toSelectOptions` (honouring the configured label/value columns), otherwise the
 * static collection maintained in the designer.
 */
const optionCollectionExpression = (node: DesignerNode, itemVariable?: string) => {
  const collectionProperty = getDesignerCollectionProperty(node.type)
  const binding = node.bindings?.[collectionProperty]
  const boundExpression = binding?.sourceId
    ? bindingExpression(node, collectionProperty, itemVariable)
    : ''
  if (boundExpression) {
    return `toSelectOptions(${boundExpression}, ${JSON.stringify(binding?.labelPath || '')}, ${JSON.stringify(binding?.valuePath || '')})`
  }
  const staticOptions = node.props[collectionProperty]
  return staticValueExpression(Array.isArray(staticOptions) ? staticOptions : [])
}

/** Node stripped of its collection prop/binding; those are rendered as children. */
const withoutCollection = (node: DesignerNode) => {
  const collectionProperty = getDesignerCollectionProperty(node.type)
  const props = { ...node.props }
  const bindings = { ...(node.bindings || {}) }
  delete props[collectionProperty]
  delete bindings[collectionProperty]
  return { node: { ...node, props, bindings }, props, bindings }
}

const propsToCode = (node: DesignerNode, itemVariable?: string, omitProperties: string[] = []) => {
  const omitted = new Set(omitProperties)
  const runtimeState = getRuntimeStateSpec(node)
  const hasBoundInputValue = node.type === 'Input' && Boolean(node.bindings?.value?.sourceId)
  const hasInputChangeHandler = Boolean(node.events?.onChange?.trim())
  const props = Object.entries(node.props)
    .filter(
      ([key, value]) =>
        key !== 'children' &&
        key !== runtimeState?.propertyName &&
        !omitted.has(key) &&
        !(node.type === 'Checkbox' && key === 'defaultChecked' && 'checked' in node.props) &&
        !(hasBoundInputValue && !hasInputChangeHandler && key === 'readOnly') &&
        !node.bindings?.[key]?.sourceId &&
        value !== '' &&
        value !== undefined,
    )
    .map(([key, value]) =>
      // Dates live in the document as ISO strings; pickers need Date instances.
      isDesignerDateProperty(node.type, key)
        ? `${key}={toDesignerDate(${staticValueExpression(value)})}`
        : `${key}=${serializeValue(value)}`,
    )

  Object.keys(node.bindings || {}).forEach((propertyName) => {
    if (propertyName === 'children') return
    const expression = bindingExpression(node, propertyName, itemVariable)
    if (expression) {
      // Label/value columns come from the bound property itself; the collection
      // is named `items` on some data components and `options` on others.
      const binding = node.bindings?.[propertyName]
      const propertyExpression = isOptionCollectionProperty(node, propertyName)
        ? `toSelectOptions(${expression}, ${JSON.stringify(binding?.labelPath || '')}, ${JSON.stringify(binding?.valuePath || '')})`
        : expression
      props.push(`${propertyName}={${propertyExpression}}`)
    }
  })

  if (hasBoundInputValue && !hasInputChangeHandler) props.push('readOnly={true}')

  if (runtimeState && !omitted.has(runtimeState.propertyName)) {
    props.push(`${runtimeState.propertyName}={${runtimeState.stateName}}`)
  }

  const handlerNames = new Set(
    Object.entries(node.events)
      .filter(([, script]) => script.trim())
      .map(([eventName]) => eventName),
  )
  if (runtimeState) handlerNames.add(runtimeState.eventName)
  handlerNames.forEach((eventName) =>
    props.push(`${eventName}={handle_${safeIdentifier(node.id)}_${eventName}}`),
  )

  // Spread first so anything configured on the node overrides the defaults.
  const leading = node.type === 'Select' ? ['{...selectMenuProps}'] : []
  const allProps = [...leading, ...props]
  return allProps.length ? ` ${allProps.join(' ')}` : ''
}

const indent = (text: string, level: number) =>
  text
    .split('\n')
    .map((line) => `${'  '.repeat(level)}${line}`)
    .join('\n')

const nodeToCode = (node: DesignerNode, level = 0, itemVariable?: string): string => {
  if (node.type === 'Spacer') {
    return indent(
      `<div aria-hidden="true" className=${JSON.stringify(String(node.props.className || ''))} style={{ height: ${Number(node.props.height) || 24} }} />`,
      level,
    )
  }

  if (node.type === 'FlexRow') {
    const style = `{ display: "flex", gap: ${Number(node.props.gap) || 0}, flexWrap: "${node.props.wrap ? 'wrap' : 'nowrap'}", alignItems: "${String(node.props.align || 'stretch')}" }`
    const className = node.props.className
      ? ` className=${JSON.stringify(node.props.className)}`
      : ''
    const children = node.children
      .map((child) => nodeToCode(child, level + 1, itemVariable))
      .join('\n')
    return `${indent(`<div${className} style={${style}}>`, level)}\n${children}\n${indent('</div>', level)}`
  }

  if (
    node.type === 'PageContainer' ||
    node.type === 'TwoColumns' ||
    node.type === 'SidebarContent' ||
    node.type === 'HeaderContent'
  ) {
    const gap = Number(node.props.gap) || 0
    const className = JSON.stringify(String(node.props.className || ''))
    const style =
      node.type === 'PageContainer'
        ? `{ display: "flex", flexDirection: "column", gap: ${gap}, margin: "0 auto", maxWidth: ${JSON.stringify(String(node.props.maxWidth || '1280px'))}, padding: ${Number(node.props.padding) || 0}, width: "100%" }`
        : node.type === 'HeaderContent'
          ? `{ display: "flex", flexDirection: "column", gap: ${gap} }`
          : `{ display: "grid", gap: ${gap}, gridTemplateColumns: ${JSON.stringify(node.type === 'SidebarContent' ? `${String(node.props.sidebarWidth || '280px')} minmax(0, 1fr)` : 'repeat(2, minmax(0, 1fr))')} }`
    const children = node.children
      .map((child) => nodeToCode(child, level + 1, itemVariable))
      .join('\n')
    return `${indent(`<div className=${className} style={${style}}>`, level)}\n${children}\n${indent('</div>', level)}`
  }

  if (node.type === 'Table') {
    const rowCount = Math.min(20, Math.max(1, Math.floor(Number(node.props.rowCount) || 2)))
    const columnCount = Math.min(20, Math.max(1, Math.floor(Number(node.props.columnCount) || 3)))
    const rows = Array.from({ length: rowCount }, (_, rowIndex) => {
      const cells = Array.from({ length: columnCount }, (_, columnIndex) => {
        const slot = `table:${rowIndex}:${columnIndex}`
        const cellChildren = node.children.filter(
          (child, childIndex) =>
            (child.slot ||
              `table:${Math.floor(childIndex / columnCount)}:${childIndex % columnCount}`) === slot,
        )
        const content = cellChildren.length
          ? cellChildren.map((child) => nodeToCode(child, level + 3, itemVariable)).join('\n')
          : indent('<span />', level + 3)
        return `${indent('<td>', level + 2)}\n${content}\n${indent('</td>', level + 2)}`
      }).join('\n')
      return `${indent('<tr>', level + 1)}\n${cells}\n${indent('</tr>', level + 1)}`
    }).join('\n')
    const className = JSON.stringify(String(node.props.className || ''))
    return `${indent(`<UiKit.Table className={${className} + " [&>tbody>tr>td]:!px-1.5 [&>tbody>tr>td]:!py-1.5"} borderlessRow compact={${Boolean(node.props.compact)}} hoverable={${node.props.hoverable !== false}} overflow={${node.props.overflow !== false}} style={{ minWidth: "100%", tableLayout: "fixed", width: "100%" }}>`, level)}
${indent('<tbody>', level + 1)}
${rows}
${indent('</tbody>', level + 1)}
${indent('</UiKit.Table>', level)}`
  }

  if (node.type === 'Grid') {
    const columns = Number(node.props.cols) || 3
    const gap = (Number(node.props.gap) || 0) * 4
    const itemsExpression =
      bindingExpression(node, 'items', itemVariable) ||
      (Array.isArray(node.props.items) ? JSON.stringify(node.props.items) : '')
    const itemsBinding = node.bindings?.items
    const sourceRootExpression =
      !itemVariable && itemsBinding?.sourceId ? `data_${safeIdentifier(itemsBinding.sourceId)}` : ''
    const collectionExpression =
      sourceRootExpression && sourceRootExpression !== itemsExpression
        ? `(Array.isArray(${itemsExpression}) ? ${itemsExpression} : Array.isArray(${sourceRootExpression}) ? ${sourceRootExpression} : null)`
        : itemsExpression
    const gridClassName = JSON.stringify(String(node.props.className || ''))
    const gridStart = `<div className=${gridClassName} style={{ display: "grid", gridTemplateColumns: "repeat(${columns}, minmax(0, 1fr))", gap: ${gap} }}>`

    if (collectionExpression && node.children.length === 0) {
      const identifier = safeIdentifier(node.id)
      const itemsVariable = `gridItems_${identifier}`
      const columnsVariable = `gridColumns_${identifier}`
      const itemVariable = `gridItem_${identifier}`
      const valueVariable = `cellValue_${identifier}`
      const configuredColumns = Array.isArray(node.props.dataColumns)
        ? node.props.dataColumns.filter((column): column is string => typeof column === 'string')
        : null
      const columnsExpression = configuredColumns
        ? JSON.stringify(configuredColumns)
        : `${itemsVariable}[0] && typeof ${itemsVariable}[0] === "object" && !Array.isArray(${itemsVariable}[0]) ? Object.keys(${itemsVariable}[0]) : ["value"]`
      const compact = Boolean(node.props.compact)
      const borderlessRow = Boolean(node.props.borderlessRow)
      const hoverable = node.props.hoverable !== false
      const overflow = node.props.overflow !== false
      const tableTextClass = compact ? 'text-[11px]' : 'text-xs'
      const cellSpacingClass = compact ? 'px-2 py-1' : 'px-3 py-2'
      const rowClass = [
        borderlessRow ? '' : 'border-b border-slate-100 last:border-b-0 dark:border-slate-800',
        hoverable ? 'transition-colors hover:bg-slate-50 dark:hover:bg-slate-800/70' : '',
      ]
        .filter(Boolean)
        .join(' ')
      const overflowClass = overflow ? 'overflow-auto' : 'overflow-visible'
      const table = `${indent('{(() => {', level + 1)}
${indent(`const ${itemsVariable} = ${collectionExpression}`, level + 2)}
${indent(`if (!Array.isArray(${itemsVariable})) return <div className="rounded-lg border border-amber-300 bg-amber-50 p-3 text-xs text-amber-800 dark:border-amber-800 dark:bg-amber-950 dark:text-amber-200">Grid items bağlantısı bir koleksiyon döndürmelidir.</div>`, level + 2)}
${indent(`const ${columnsVariable} = ${columnsExpression}`, level + 2)}
${indent(`if (!${columnsVariable}.length) return <div className="rounded-lg border border-dashed border-slate-300 bg-slate-50 p-4 text-center text-xs text-slate-500 dark:border-slate-700 dark:bg-slate-900 dark:text-slate-400">Preview için en az bir sütun seçin.</div>`, level + 2)}
${indent('return (', level + 2)}
${indent(`<div className="min-w-0 ${overflowClass} rounded-lg border border-slate-200 bg-white shadow-sm dark:border-slate-700 dark:bg-slate-900" style={{ gridColumn: "1 / -1" }}>`, level + 3)}
${indent(`<table className="w-full border-collapse text-left ${tableTextClass}">`, level + 4)}
${indent('<thead className="bg-slate-100 text-slate-600 dark:bg-slate-800 dark:text-slate-200"><tr>', level + 5)}
${indent(`{${columnsVariable}.map((column) => <th key={column} className="whitespace-nowrap border-b border-slate-200 dark:border-slate-700 ${cellSpacingClass}">{column === "value" ? "Value" : column}</th>)}`, level + 6)}
${indent('</tr></thead>', level + 5)}
${indent('<tbody>', level + 5)}
${indent(`{${itemsVariable}.map((${itemVariable}, rowIndex) => (`, level + 6)}
${indent(`<tr key={rowIndex} className=${JSON.stringify(rowClass)}>`, level + 7)}
${indent(`{${columnsVariable}.map((column) => {`, level + 8)}
${indent(`const ${valueVariable} = column === "value" ? ${itemVariable} : getByPath(${itemVariable}, column)`, level + 9)}
${indent(`const text = typeof ${valueVariable} === "object" && ${valueVariable} !== null ? JSON.stringify(${valueVariable}) : String(${valueVariable} ?? "") || "—"`, level + 9)}
${indent(`return <td key={column} className="max-w-64 truncate text-slate-800 dark:text-slate-100 ${cellSpacingClass}" title={text}>{text}</td>`, level + 9)}
${indent('})}', level + 8)}
${indent('</tr>', level + 7)}
${indent('))}', level + 6)}
${indent('</tbody>', level + 5)}
${indent('</table>', level + 4)}
${indent('</div>', level + 3)}
${indent(')', level + 2)}
${indent('})()}', level + 1)}`
      return `${indent(gridStart, level)}\n${table}\n${indent('</div>', level)}`
    }

    const repeatedItemVariable = `item_${safeIdentifier(node.id)}`
    const staticChildren = node.children
      .map((child) => nodeToCode(child, level + 1, itemVariable))
      .join('\n')
    const repeatedChildren = node.children.length
      ? node.children.map((child) => nodeToCode(child, level + 3, repeatedItemVariable)).join('\n')
      : indent(
          `<pre className="min-w-0 overflow-auto rounded-lg border border-slate-200 bg-white p-3 text-xs text-slate-800 shadow-sm dark:border-slate-700 dark:bg-slate-900 dark:text-slate-100">{typeof ${repeatedItemVariable} === "string" ? ${repeatedItemVariable} : JSON.stringify(${repeatedItemVariable}, null, 2)}</pre>`,
          level + 3,
        )
    const children = collectionExpression
      ? `${indent(`{Array.isArray(${collectionExpression}) ? ${collectionExpression}.map((${repeatedItemVariable}, index) => (`, level + 1)}
${indent(`<React.Fragment key={${repeatedItemVariable}?.id ?? index}>`, level + 2)}
${repeatedChildren}
${indent('</React.Fragment>', level + 2)}
${indent(')) : (', level + 1)}
${indent('<div className="rounded-lg border border-amber-300 bg-amber-50 p-3 text-xs text-amber-800 dark:border-amber-800 dark:bg-amber-950 dark:text-amber-200">Grid items bağlantısı bir koleksiyon döndürmelidir.</div>', level + 2)}
${indent(')}', level + 1)}`
      : staticChildren
    return `${indent(gridStart, level)}\n${children}\n${indent('</div>', level)}`
  }

  if (node.kind === 'platform') {
    const viewNames: Record<string, string> = {
      ListView: 'List',
      DataGridView: 'Grid',
      TreeView: 'Tree',
      GanttView: 'GanttView',
      TodoBoard: 'TodoBoard',
      CardView: 'CardView',
      SchedulerView: 'SchedulerView',
      PivotView: 'Pivot',
      ChartView: 'Chart',
    }
    return indent(
      `<PlatformViewHost view=${JSON.stringify(viewNames[node.type] || node.type)} listFormCode=${JSON.stringify(String(node.props.listFormCode || ''))} height=${JSON.stringify(String(node.props.height || '420px'))} />`,
      level,
    )
  }

  if (node.type === 'Menu') {
    const { node: menuNode, props: menuProps } = withoutCollection(node)
    delete menuProps.variant
    menuProps.defaultActiveKeys = normalizeDesignerKeyList(menuProps.defaultActiveKeys)
    menuProps.defaultExpandedKeys = normalizeDesignerKeyList(menuProps.defaultExpandedKeys)
    const menuPropsCode = propsToCode(menuNode, itemVariable)
    const optionsExpression = optionCollectionExpression(node, itemVariable)
    return `${indent(`<UiKit.Menu${menuPropsCode}>`, level)}\n${indent(`{${optionsExpression}.map((option, optionIndex) => <UiKit.Menu.MenuItem key={String(option.value ?? optionIndex)} eventKey={String(option.value ?? optionIndex)}>{String(option.label ?? option.value ?? \`Menü \${optionIndex + 1}\`)}</UiKit.Menu.MenuItem>)}`, level + 1)}\n${indent('</UiKit.Menu>', level)}`
  }

  if (node.type === 'Dropdown') {
    const { node: dropdownNode, props: dropdownProps, bindings } = withoutCollection(node)
    // Rendered from the active option below, so `title` must not also be emitted
    // by propsToCode — whether it is static or bound to an endpoint field.
    const boundTitle = bindings.title?.sourceId
      ? bindingExpression(node, 'title', itemVariable)
      : ''
    const fallbackTitleExpression = boundTitle || staticValueExpression(dropdownProps.title ?? '')
    delete dropdownProps.title
    delete bindings.title
    const dropdownPropsCode = propsToCode(dropdownNode, itemVariable)
    const optionsExpression = optionCollectionExpression(node, itemVariable)
    const activeKeyExpression =
      getRuntimeStateSpec(node)?.stateName ||
      bindingExpression(node, 'activeKey', itemVariable) ||
      staticValueExpression(node.props.activeKey ?? '')
    const titleExpression = `toDropdownTitle(${optionsExpression}, ${activeKeyExpression}, ${fallbackTitleExpression})`
    return `${indent(`<UiKit.Dropdown${dropdownPropsCode} title={${titleExpression}}>`, level)}\n${indent(`{${optionsExpression}.map((option, optionIndex) => <UiKit.Dropdown.Item key={String(option.value ?? optionIndex)} eventKey={String(option.value ?? optionIndex)} disabled={Boolean(option.disabled)}>{String(option.label ?? option.value ?? \`Öğe \${optionIndex + 1}\`)}</UiKit.Dropdown.Item>)}`, level + 1)}\n${indent('</UiKit.Dropdown>', level)}`
  }

  if (node.type === 'Pagination') {
    const { node: paginationNode } = withoutCollection(node)
    const paginationPropsCode = propsToCode(paginationNode, itemVariable)
    const optionsExpression = optionCollectionExpression(node, itemVariable)
    return indent(
      `<UiKit.Pagination${paginationPropsCode} total={${optionsExpression}.length} />`,
      level,
    )
  }

  if (node.type === 'Tabs') {
    const { node: tabsNode } = withoutCollection(node)
    // `value` is emitted below, resolved against the (possibly async) tab list.
    const tabsPropsCode = propsToCode(tabsNode, itemVariable, ['value'])
    const identifier = safeIdentifier(node.id)
    const optionsVariable = `tabItems_${identifier}`
    const activeVariable = `tabValue_${identifier}`
    const optionVariable = `tabItem_${identifier}`
    const activeStateExpression =
      getRuntimeStateSpec(node)?.stateName ||
      bindingExpression(node, 'value', itemVariable) ||
      staticValueExpression(node.props.value ?? '')
    const childrenVariable = `tabChildren_${identifier}`
    const fallbackVariable = `tabFallback_${identifier}`

    // Children are assigned to a tab through a `tab:<value>` slot. Building a
    // lookup keyed by tab value keeps this working when the tab list itself is
    // only known at runtime (endpoint driven tabs).
    const slotGroups = new Map<string, DesignerNode[]>()
    node.children.forEach((child) => {
      const key = getDesignerTabSlotValue(child.slot)
      const group = slotGroups.get(key)
      if (group) group.push(child)
      else slotGroups.set(key, [child])
    })
    const fragmentFor = (children: DesignerNode[], fragmentLevel: number) =>
      `${indent('<>', fragmentLevel)}\n${children
        .map((child) => nodeToCode(child, fragmentLevel + 1, itemVariable))
        .join('\n')}\n${indent('</>', fragmentLevel)}`

    const slottedEntries = [...slotGroups]
      .filter(([key]) => key !== '')
      .map(
        ([key, children]) =>
          `${indent(`${JSON.stringify(key)}: (`, level + 2)}\n${fragmentFor(children, level + 3)}\n${indent('),', level + 2)}`,
      )
      .join('\n')
    // Children saved before per-tab slots existed belong to the first tab.
    const fallbackChildren = slotGroups.get('') || []

    return `${indent('{(() => {', level)}
${indent(`const ${optionsVariable} = ${optionCollectionExpression(node, itemVariable)}`, level + 1)}
${indent(`const ${activeVariable} = toTabValue(${optionsVariable}, ${activeStateExpression})`, level + 1)}
${indent(`const ${childrenVariable} = {`, level + 1)}
${slottedEntries}
${indent('}', level + 1)}
${indent(`const ${fallbackVariable} = (`, level + 1)}
${fallbackChildren.length ? fragmentFor(fallbackChildren, level + 2) : indent('null', level + 2)}
${indent(')', level + 1)}
${indent('return (', level + 1)}
${indent(`<UiKit.Tabs${tabsPropsCode} value={${activeVariable}}>`, level + 2)}
${indent('<UiKit.Tabs.TabList>', level + 3)}
${indent(`{${optionsVariable}.map((${optionVariable}, tabIndex) => <UiKit.Tabs.TabNav key={String(${optionVariable}.value ?? tabIndex)} value={String(${optionVariable}.value ?? tabIndex)} disabled={Boolean(${optionVariable}.disabled)}>{String(${optionVariable}.label ?? ${optionVariable}.value ?? \`Sekme \${tabIndex + 1}\`)}</UiKit.Tabs.TabNav>)}`, level + 4)}
${indent('</UiKit.Tabs.TabList>', level + 3)}
${indent(`{${optionsVariable}.map((${optionVariable}, tabIndex) => (`, level + 3)}
${indent(`<UiKit.Tabs.TabContent key={String(${optionVariable}.value ?? tabIndex)} value={String(${optionVariable}.value ?? tabIndex)}>`, level + 4)}
${indent(`{${optionVariable}.content ? <div>{String(${optionVariable}.content)}</div> : null}`, level + 5)}
${indent(`{${childrenVariable}[String(${optionVariable}.value ?? tabIndex)] ?? null}`, level + 5)}
${indent(`{tabIndex === 0 ? ${fallbackVariable} : null}`, level + 5)}
${indent('</UiKit.Tabs.TabContent>', level + 4)}
${indent('))}', level + 3)}
${indent('</UiKit.Tabs>', level + 2)}
${indent(')', level + 1)}
${indent('})()}', level)}`
  }

  if (node.type === 'Radio.Group') {
    const { node: groupNode, props: groupProps } = withoutCollection(node)
    delete groupProps.checked
    delete groupProps.defaultChecked
    delete groupProps.readOnly
    const groupPropsCode = propsToCode(groupNode, itemVariable)
    const optionsExpression = optionCollectionExpression(node, itemVariable)
    return `${indent(`<UiKit.Radio.Group${groupPropsCode}>`, level)}\n${indent(`{${optionsExpression}.map((option, optionIndex) => <UiKit.Radio key={String(option.value ?? optionIndex)} value={option.value ?? optionIndex} disabled={Boolean(option.disabled)}>{String(option.label ?? option.value ?? \`Seçenek \${optionIndex + 1}\`)}</UiKit.Radio>)}`, level + 1)}\n${indent('</UiKit.Radio.Group>', level)}`
  }

  const tag =
    node.type === 'checkbox'
      ? 'input'
      : node.kind === 'ui'
        ? `UiKit.${node.type}`
        : node.kind === 'custom'
          ? safeIdentifier(node.type)
          : node.type
  const props = { ...node.props }
  if (node.type === 'checkbox') props.type = 'checkbox'
  const normalizedNode = { ...node, props }
  const propCode = propsToCode(normalizedNode, itemVariable)
  const childrenText = String(node.props.children ?? '')
  const childrenBinding = bindingExpression(node, 'children', itemVariable)
  const hasChildren = node.children.length > 0 || childrenText.length > 0 || !!childrenBinding
  const voidElement = ['input', 'img'].includes(tag)

  if (voidElement) return indent(`<${tag}${propCode} />`, level)
  if (!hasChildren) return indent(`<${tag}${propCode} />`, level)

  const nested = node.children.map((child) => nodeToCode(child, level + 1, itemVariable)).join('\n')
  const text = childrenBinding
    ? indent(`{${childrenBinding}}`, level + 1)
    : childrenText
      ? indent(`{${staticValueExpression(childrenText)}}`, level + 1)
      : ''
  const body = [text, nested].filter(Boolean).join('\n')
  return `${indent(`<${tag}${propCode}>`, level)}\n${body}\n${indent(`</${tag}>`, level)}`
}

export const generateDesignerCode = (name: string, document: DesignerDocument) => {
  const componentName = safeIdentifier(name || 'VisualComponent')
  const handlers: string[] = []
  const runtimeStateHooks: string[] = []
  let hasSelect = false
  let hasDataTable = false
  let hasDropdown = false
  let hasSelectComponent = false
  let hasDatePicker = false
  let hasTabs = false

  const visit = (nodes: DesignerNode[]) => {
    nodes.forEach((node) => {
      if (isDesignerOptionComponent(node.type)) hasSelect = true
      if (node.type === 'Select') hasSelectComponent = true
      if (node.type === 'Dropdown') hasDropdown = true
      if (node.type === 'Grid') hasDataTable = true
      if (node.type === 'Tabs') hasTabs = true
      if (isDesignerDateComponent(node.type)) hasDatePicker = true
      const runtimeState = getRuntimeStateSpec(node)
      if (runtimeState) {
        // Date pickers hold a Date in state but an ISO string in the document.
        const initialExpression = isDesignerDateProperty(node.type, runtimeState.propertyName)
          ? `toDesignerDate(${JSON.stringify(runtimeState.initialValue ?? null)})`
          : JSON.stringify(runtimeState.initialValue)
        runtimeStateHooks.push(
          `  const [${runtimeState.stateName}, ${runtimeState.setterName}] = React.useState(${initialExpression})`,
        )
      }
      const eventNames = new Set(
        Object.entries(node.events)
          .filter(([, script]) => script.trim())
          .map(([eventName]) => eventName),
      )
      if (runtimeState) eventNames.add(runtimeState.eventName)
      eventNames.forEach((eventName) => {
        const script = node.events[eventName]?.trim() || ''
        const stateUpdate =
          runtimeState?.eventName === eventName
            ? node.type === 'Select'
              ? `${runtimeState.setterName}(valueOrEvent)`
              : node.type === 'AutoComplete'
                ? `${runtimeState.setterName}(valueOrEvent ?? "")`
                : node.type === 'Menu'
                  ? `${runtimeState.setterName}([String(valueOrEvent ?? "")])`
                  : node.type === 'Tabs'
                    ? `${runtimeState.setterName}(String(valueOrEvent ?? ""))`
                    : node.type === 'Dropdown'
                      ? `${runtimeState.setterName}(String(valueOrEvent ?? ""))`
                      : node.type === 'Pagination'
                        ? `${runtimeState.setterName}(Number(valueOrEvent) || 1)`
                        : node.type === 'Steps' || node.type === 'ImageViewer'
                          ? `${runtimeState.setterName}(Number(valueOrEvent) || 0)`
                          : node.type === 'Upload'
                            ? `${runtimeState.setterName}(Array.isArray(originalEvent) ? originalEvent : [])`
                            : runtimeState.propertyName === 'checked'
                              ? `${runtimeState.setterName}(typeof originalEvent === "object" && originalEvent?.target ? Boolean(originalEvent.target.checked) : typeof valueOrEvent === "object" && valueOrEvent?.target ? Boolean(valueOrEvent.target.checked) : Boolean(valueOrEvent))`
                              : node.type === 'Input' || node.kind === 'html'
                                ? `${runtimeState.setterName}(valueOrEvent?.target?.value ?? valueOrEvent)`
                                : `${runtimeState.setterName}(valueOrEvent)`
            : ''
        const eventDeclaration =
          node.type === 'Checkbox' && eventName === 'onChange'
            ? '    const event = { checked: Boolean(valueOrEvent), originalEvent, target: originalEvent?.target }'
            : '    const event = valueOrEvent'
        handlers.push(
          `  const handle_${safeIdentifier(node.id)}_${eventName} = (valueOrEvent, originalEvent) => {\n${stateUpdate ? `    ${stateUpdate}\n` : ''}${eventDeclaration}${script ? `\n${indent(script, 2)}` : ''}\n  }`,
        )
      })
      visit(node.children)
    })
  }
  visit(document.nodes)

  const dataSources = document.dataSources || []
  const selectHelpers = hasSelect
    ? `  const toSelectOptions = (value, labelPath = "", valuePath = "") => {
    if (!Array.isArray(value)) return []
    return value.map((item, index) => {
      if (item === null || typeof item !== "object" || Array.isArray(item)) return { label: String(item ?? ""), value: item ?? index }
      const primitiveKeys = Object.keys(item).filter((key) => item[key] === null || ["string", "number", "boolean"].includes(typeof item[key]))
      const labelKey = ["label", "children", "name", "title", "text", "description"].find((key) => item[key] !== undefined)
      const valueKey = ["value", "eventKey", "id", "code", "key"].find((key) => item[key] !== undefined)
      const optionLabel = labelPath ? getByPath(item, labelPath) : item[labelKey ?? primitiveKeys[0]]
      const optionValue = valuePath ? getByPath(item, valuePath) : item[valueKey ?? primitiveKeys[1] ?? primitiveKeys[0]]
      return { ...item, label: String(optionLabel ?? \`Seçenek \${index + 1}\`), value: optionValue ?? index }
    })
  }`
    : ''
  // Dropdown paints its toggle from `title`; `activeKey` only marks the item
  // inside the closed menu, so the label of the active option is resolved here.
  const dropdownHelpers = hasDropdown
    ? `  const toDropdownTitle = (options, activeKey, fallbackTitle) => {
    const key = activeKey === undefined || activeKey === null ? "" : String(activeKey)
    const selected = key ? options.find((option) => String(option?.value ?? "") === key) : undefined
    if (selected) return String(selected.label ?? selected.value ?? key)
    return String(fallbackTitle ?? "") || ${JSON.stringify(DESIGNER_DROPDOWN_PLACEHOLDER)}
  }`
    : ''
  // Falls back to the first tab while an endpoint driven tab list is still empty
  // or when the stored value no longer exists.
  const tabHelpers = hasTabs
    ? `  const toTabValue = (options, value) => {
    const key = value === undefined || value === null ? "" : String(value)
    if (key && options.some((option) => String(option?.value ?? "") === key)) return key
    return options.length ? String(options[0]?.value ?? "") : ""
  }`
    : ''
  // Pickers check `instanceof Date`, but the document only stores ISO strings.
  const dateHelpers = hasDatePicker
    ? `  const toDesignerDate = (value) => {
    if (Array.isArray(value)) return value.map(toDesignerDate)
    if (value instanceof Date) return Number.isNaN(value.getTime()) ? null : value
    if (typeof value !== "string" || !value.trim()) return null
    const parsed = new Date(value)
    return Number.isNaN(parsed.getTime()) ? null : parsed
  }`
    : ''
  // Select renders its menu inline, so a scrollable/clipped ancestor (Grid, Table,
  // Card) would cut it off. A body portal keeps the menu fully visible.
  const selectMenuHelpers = hasSelectComponent
    ? `  const selectMenuProps = {
    menuPosition: "fixed",
    menuPortalTarget: typeof window === "undefined" ? null : window.document.body,
    styles: { menuPortal: (base) => ({ ...base, zIndex: 60 }) },
  }`
    : ''
  const dataHelpers =
    dataSources.length || hasDataTable
      ? `  const getByPath = (value, path) => {
    if (!path) return value
    const readPath = (target, targetPath) => targetPath.split('.').filter(Boolean).reduce((current, key) => current?.[key], target)
    const directValue = readPath(value, path)
    if (directValue !== undefined) return directValue
    if (path.startsWith('result.')) return readPath(value, path.slice('result.'.length))
    return value?.result === undefined ? undefined : readPath(value.result, path)
  }`
      : ''
  const dataHooks = dataSources
    .map((source) => {
      const identifier = safeIdentifier(source.id)
      if (!source.url.trim().startsWith('/api/')) {
        return `  const [data_${identifier}] = React.useState(null)`
      }
      return `  const [data_${identifier}, setData_${identifier}] = React.useState(null)
  React.useEffect(() => {
    let active = true
    apiService.fetchData({ url: ${JSON.stringify(source.url)}, method: 'GET' }).then((response) => {
      if (active) setData_${identifier}(getByPath(response.data, ${JSON.stringify(source.responsePath || '')}))
    }).catch((error) => console.error(${JSON.stringify(`${source.name} endpoint error:`)}, error))
    return () => { active = false }
  }, [])`
    })
    .join('\n\n')

  const mount = document.lifecycle.onMount.trim()
    ? `  React.useEffect(() => {\n${indent(document.lifecycle.onMount, 2)}\n  }, [])`
    : ''
  const body = document.nodes.map((node) => nodeToCode(node, 3)).join('\n')

  const designerBackup = encodeURIComponent(JSON.stringify(document))

  return `/*__SOZSOFT_VISUAL_DESIGNER__${designerBackup}__*/\nconst ${componentName} = () => {\n${[dataHelpers, selectHelpers, dropdownHelpers, selectMenuHelpers, dateHelpers, tabHelpers, dataHooks, ...runtimeStateHooks, mount, ...handlers].filter(Boolean).join('\n\n')}\n\n  return (\n    <>\n${body}\n    </>\n  )\n}\n\nexport default ${componentName}\n`
}