Method resolveLength

src/parser/indirect-object-parser.ts:355–389

* Resolve the /Length value from the stream dict. * Handles both direct values and indirect references.

(dict: PdfDict)

   * Handles both direct values and indirect references.
   */
  private resolveLength(dict: PdfDict): number {
    const lengthObj = dict.get("Length");

    if (lengthObj === undefined) {
      throw new ObjectParseError("Stream missing required /Length entry");
    }

    // Direct number
    if (lengthObj.type === "number") {
      return lengthObj.value;
    }

    // Indirect reference
    if (lengthObj.type === "ref") {
      const ref = lengthObj;

      if (!this.lengthResolver) {
        throw new ObjectParseError(
          `Cannot resolve indirect /Length reference ${ref.objectNumber} ${ref.generation} R: no resolver provided`,
        );
      }

      const length = this.lengthResolver(ref);

      if (length === null) {
        throw new ObjectParseError(
          `Could not resolve /Length reference ${ref.objectNumber} ${ref.generation} R`,
        );
      }

      return length;
    }

    throw new ObjectParseError(`Invalid /Length type: ${lengthObj.type}`);
  }
}