import type { FieldRules } from '../composables/useForm'
import type { OptionPrimitive, SelectOption } from './components'
import type { AccessControlled } from '../permissions'

// ---------------------------------------------------------------------------
// Field types
// ---------------------------------------------------------------------------

/** All supported field types that map to SDK components. */
export type FormFieldType =
  | 'text'
  | 'email'
  | 'password'
  | 'secret'
  | 'number'
  | 'tel'
  | 'url'
  | 'search'
  | 'textarea'
  | 'select'
  | 'multiselect'
  | 'checkbox'
  | 'toggle'
  | 'radio'
  | 'slider'
  | 'tags'
  | 'date'
  | 'time'
  | 'datetime'
  | 'file'
  | 'path'
  | 'formula'
  | 'sequence'
  | 'molecule'
  | 'concentration'
  | 'unit'

// ---------------------------------------------------------------------------
// Conditions (JSON-serializable)
// ---------------------------------------------------------------------------

export type FieldCondition =
  | { field: string; eq: unknown }
  | { field: string; neq: unknown }
  | { field: string; gt: number }
  | { field: string; lt: number }
  | { field: string; gte: number }
  | { field: string; lte: number }
  | { field: string; in: unknown[] }
  | { field: string; notIn: unknown[] }
  | { field: string; truthy: true }
  | { field: string; falsy: true }
  | { field: string; contains: string }
  | { and: FieldCondition[] }
  | { or: FieldCondition[] }
  | { not: FieldCondition }

// ---------------------------------------------------------------------------
// Validation (JSON-safe subset of FieldRules)
// ---------------------------------------------------------------------------

export interface FieldValidation {
  required?: boolean | string
  minLength?: number | { value: number; message: string }
  maxLength?: number | { value: number; message: string }
  min?: number | { value: number; message: string }
  max?: number | { value: number; message: string }
  /** Pattern as a string (converted to RegExp at runtime). */
  pattern?: string | { value: string; message: string }
  email?: boolean | string
}

// ---------------------------------------------------------------------------
// Field schema
// ---------------------------------------------------------------------------

export interface FormFieldSchema extends AccessControlled {
  name: string
  label: string
  type: FormFieldType
  defaultValue?: unknown
  placeholder?: string
  hint?: string
  icon?: string | string[]
  iconColor?: string
  iconBg?: string
  size?: 'sm' | 'md' | 'lg'
  disabled?: boolean
  readonly?: boolean
  validation?: FieldValidation
  condition?: FieldCondition
  /** Grid column span (1-3). Defaults to 1. */
  colSpan?: number
  /** Extra props passed directly to the underlying component. */
  props?: Record<string, unknown>
  /** Element type for `tags` fields; `number` parses each entered tag back to a number. */
  itemType?: 'string' | 'number'
}

export type FormOptionInput = SelectOption<unknown> | OptionPrimitive

// ---------------------------------------------------------------------------
// Section schema
// ---------------------------------------------------------------------------

export interface FormSectionSchema {
  id: string
  title: string
  description?: string
  collapsible?: boolean
  defaultOpen?: boolean
  /** Number of grid columns (1-3). Defaults to 1. */
  columns?: 1 | 2 | 3
  fields: FormFieldSchema[]
  condition?: FieldCondition
}

// ---------------------------------------------------------------------------
// Wizard step schema
// ---------------------------------------------------------------------------

export interface FormStepSchema {
  id: string
  label: string
  description?: string
  icon?: string
  optional?: boolean
  sections: FormSectionSchema[]
}

// ---------------------------------------------------------------------------
// Top-level form schema
// ---------------------------------------------------------------------------

export type FormSchema =
  | {
      sections: FormSectionSchema[]
      steps?: never
      submitLabel?: string
      cancelLabel?: string
      showCancel?: boolean
    }
  | {
      sections?: never
      steps: FormStepSchema[]
      submitLabel?: string
      cancelLabel?: string
      showCancel?: boolean
    }

// ---------------------------------------------------------------------------
// Enhancements (TS-only, NOT JSON-serializable)
// ---------------------------------------------------------------------------

export interface FieldEnhancement<T extends Record<string, unknown> = Record<string, unknown>> {
  /** Custom validator appended to the field's rules. */
  validate?: (value: unknown, data: T) => string | undefined | null
  /** Dynamic visibility (overrides schema condition if both present). */
  visible?: (data: T) => boolean
  /** Dynamic options for select/multiselect/radio fields. */
  options?: (data: T) => FormOptionInput[]
  /** Dynamic extra props merged into the component. */
  props?: (data: T) => Record<string, unknown>
}

export interface FormEnhancements<T extends Record<string, unknown> = Record<string, unknown>> {
  /** Per-field enhancements keyed by field name. */
  fields?: Partial<Record<keyof T, FieldEnhancement<T>>>
  /** Called on successful submit. */
  onSubmit?: (data: T) => Promise<void> | void
  /** Transform data before submit (return transformed copy). */
  transform?: (data: T) => T | Record<string, unknown>
  /** Called when any field value changes. */
  onFieldChange?: (field: keyof T, value: unknown, data: T) => void
}

// ---------------------------------------------------------------------------
// useFormBuilder return type
// ---------------------------------------------------------------------------

export interface UseFormBuilderReturn<T extends Record<string, unknown>> {
  /** Underlying useForm return. */
  form: import('../composables/useForm').UseFormReturn<T>
  /** Validation rules derived from schema + enhancements. */
  rules: Partial<Record<keyof T, FieldRules>>
  /** Whether a field is currently visible. */
  isFieldVisible: (name: string) => boolean
  /** Whether a section is currently visible. */
  isSectionVisible: (id: string) => boolean
  /** All flattened field schemas. */
  fields: FormFieldSchema[]
  /** Resolve final component props for a field. */
  getResolvedFieldProps: (field: FormFieldSchema) => Record<string, unknown>
  /** Get options for a select/radio/multiselect field. */
  getFieldOptions: (name: string) => FormOptionInput[] | undefined

  // Wizard-specific
  currentStep: import('vue').Ref<number>
  isCurrentStepValid: import('vue').ComputedRef<boolean>
  goNext: () => boolean
  goBack: () => void
  goToStep: (index: number) => void

  // Actions
  validate: () => boolean
  reset: (values?: Partial<T>) => void
  submit: () => Promise<void>
  /** Replace the active schema and rebuild field state for still-mounted forms. */
  updateSchema: (schema: FormSchema, values?: Partial<T>) => void
}