import type { BlockLike } from './durableMarkdownBlocks'

export const TOLARIA_CALLOUT_BLOCK_TYPE = 'tolariaCallout'

export const TOLARIA_CALLOUT_KINDS = [
  'info',
  'success',
  'warning',
  'danger',
  'annotation',
  'relationship',
  'path',
] as const

export type TolariaCalloutKind = typeof TOLARIA_CALLOUT_KINDS[number]

const CALLOUT_MARKER_RE = /^\[!(info|success|warning|danger|annotation|relationship|path)\]\s*(.*)$/iu

function isCalloutKind(value: unknown): value is TolariaCalloutKind {
  return typeof value === 'string' && TOLARIA_CALLOUT_KINDS.includes(value as TolariaCalloutKind)
}

function readTextOnlyContent(content: BlockLike['content']): string | null {
  if (!Array.isArray(content) || content.length === 0) return null

  let text = ''
  for (const item of content) {
    if (item.type !== 'text' || typeof item.text !== 'string') return null
    text += item.text
  }
  return text
}

function calloutMatchFromQuote(block: BlockLike) {
  if (block.type !== 'quote') return null

  const text = readTextOnlyContent(block.content)
  if (text === null) return null

  const match = CALLOUT_MARKER_RE.exec(text)
  if (!match) return null

  const kind = match[1]?.toLowerCase()
  if (!isCalloutKind(kind)) return null

  return {
    kind,
    text: match[2] ?? '',
  }
}

export function injectTolariaCalloutBlocks(blocks: unknown[]): unknown[] {
  return (blocks as BlockLike[]).map((block) => {
    const match = calloutMatchFromQuote(block)
    const children = Array.isArray(block.children)
      ? injectTolariaCalloutBlocks(block.children) as BlockLike[]
      : block.children

    if (!match) return { ...block, children }

    return {
      ...block,
      type: TOLARIA_CALLOUT_BLOCK_TYPE,
      props: {
        ...(block.props ?? {}),
        kind: match.kind,
      },
      content: match.text
        ? [{ type: 'text', text: match.text, styles: {} }]
        : [],
      children,
    }
  })
}

export function calloutKind(value: unknown): TolariaCalloutKind {
  return isCalloutKind(value) ? value : 'info'
}