get viewerPreferences()

in src/core/catalog.js [888:1012]
121 lines of code
53 McCabe index (conditional complexity)

  get viewerPreferences() {
    const obj = this._catDict.get("ViewerPreferences");
    if (!(obj instanceof Dict)) {
      return shadow(this, "viewerPreferences", null);
    }
    let prefs = null;

    for (const [key, value] of obj) {
      let prefValue;

      switch (key) {
        case "HideToolbar":
        case "HideMenubar":
        case "HideWindowUI":
        case "FitWindow":
        case "CenterWindow":
        case "DisplayDocTitle":
        case "PickTrayByPDFSize":
          if (typeof value === "boolean") {
            prefValue = value;
          }
          break;
        case "NonFullScreenPageMode":
          if (value instanceof Name) {
            switch (value.name) {
              case "UseNone":
              case "UseOutlines":
              case "UseThumbs":
              case "UseOC":
                prefValue = value.name;
                break;
              default:
                prefValue = "UseNone";
            }
          }
          break;
        case "Direction":
          if (value instanceof Name) {
            switch (value.name) {
              case "L2R":
              case "R2L":
                prefValue = value.name;
                break;
              default:
                prefValue = "L2R";
            }
          }
          break;
        case "ViewArea":
        case "ViewClip":
        case "PrintArea":
        case "PrintClip":
          if (value instanceof Name) {
            switch (value.name) {
              case "MediaBox":
              case "CropBox":
              case "BleedBox":
              case "TrimBox":
              case "ArtBox":
                prefValue = value.name;
                break;
              default:
                prefValue = "CropBox";
            }
          }
          break;
        case "PrintScaling":
          if (value instanceof Name) {
            switch (value.name) {
              case "None":
              case "AppDefault":
                prefValue = value.name;
                break;
              default:
                prefValue = "AppDefault";
            }
          }
          break;
        case "Duplex":
          if (value instanceof Name) {
            switch (value.name) {
              case "Simplex":
              case "DuplexFlipShortEdge":
              case "DuplexFlipLongEdge":
                prefValue = value.name;
                break;
              default:
                prefValue = "None";
            }
          }
          break;
        case "PrintPageRange":
          // The number of elements must be even.
          if (Array.isArray(value) && value.length % 2 === 0) {
            const isValid = value.every(
              (page, i, arr) =>
                Number.isInteger(page) &&
                page > 0 &&
                (i === 0 || page >= arr[i - 1]) &&
                page <= this.numPages
            );
            if (isValid) {
              prefValue = value;
            }
          }
          break;
        case "NumCopies":
          if (Number.isInteger(value) && value > 0) {
            prefValue = value;
          }
          break;
        default:
          warn(`Ignoring non-standard key in ViewerPreferences: ${key}.`);
          continue;
      }

      if (prefValue === undefined) {
        warn(`Bad value, for key "${key}", in ViewerPreferences: ${value}.`);
        continue;
      }
      prefs ??= Object.create(null);
      prefs[key] = prefValue;
    }
    return shadow(this, "viewerPreferences", prefs);
  }