import type { MetadataEvent } from './types'
import { isRecord } from './utils'

export function extractMetadataJsonFromTag(event: MetadataEvent): Record<string, unknown> | null {
  const jsonTag = event.tags.find((tag) => tag[0] === 'json')
  if (!jsonTag?.[1]) {
    return null
  }
  try {
    const parsed: unknown = JSON.parse(jsonTag[1])
    return isRecord(parsed) ? parsed : null
  } catch (e) {
    console.error('[metadataExtractor] Error parsing JSON metadata from tag:', e)
    return null
  }
}

export function extractMetadataJson(content: string): Record<string, unknown> | null {
  const invisibleJsonMatch = content.match(/[\u200B\u200C]\[Metadata JSON\][\u200B\u200C]\n[\u200B\u200C](.+)[\u200B\u200C]$/s)
  if (invisibleJsonMatch?.[1]) {
    try {
      const cleanedJson = invisibleJsonMatch[1].replace(/[\u200B\u200C\u200D\u200E\u200F]/g, '').trim()
      const parsed: unknown = JSON.parse(cleanedJson)
      return isRecord(parsed) ? parsed : null
    } catch (e) {
      console.error('[metadataExtractor] Error parsing metadata JSON from invisible content:', e)
    }
  }

  const jsonMatch = content.match(/\[Metadata JSON\]\n(.+)$/s)
  if (jsonMatch?.[1]) {
    try {
      const parsed: unknown = JSON.parse(jsonMatch[1].trim())
      return isRecord(parsed) ? parsed : null
    } catch (e) {
      console.error('[metadataExtractor] Error parsing metadata JSON from content:', e)
      return null
    }
  }

  return null
}

export function getMetadataFromEvent(event: MetadataEvent & { content: string }): Record<string, unknown> | null {
  return extractMetadataJsonFromTag(event) ?? extractMetadataJson(event.content)
}