Function extractLastJsonStringField

src/utils/sessionStoragePortable.ts:82–111

(
  text: string,
  key: string,
)

 * Useful for fields that are appended (customTitle, tag, etc.).
 */
export function extractLastJsonStringField(
  text: string,
  key: string,
): string | undefined {
  const patterns = [`"${key}":"`, `"${key}": "`]
  let lastValue: string | undefined
  for (const pattern of patterns) {
    let searchFrom = 0
    while (true) {
      const idx = text.indexOf(pattern, searchFrom)
      if (idx < 0) break

      const valueStart = idx + pattern.length
      let i = valueStart
      while (i < text.length) {
        if (text[i] === '\\') {
          i += 2
          continue
        }
        if (text[i] === '"') {
          lastValue = unescapeJsonString(text.slice(valueStart, i))
          break
        }
        i++
      }
      searchFrom = i + 1
    }
  }
  return lastValue
}

// ---------------------------------------------------------------------------
// First prompt extraction from head chunk