import PDFDocument from 'src/api/PDFDocument';

import PDFPage from 'src/api/PDFPage';

import PDFFont from 'src/api/PDFFont';

import PDFImage from 'src/api/PDFImage';

import PDFField, {

FieldAppearanceOptions,

assertFieldAppearanceOptions,

} from 'src/api/form/PDFField';

import {

AppearanceProviderFor,

normalizeAppearance,

defaultTextFieldAppearanceProvider,

} from 'src/api/form/appearances';

import { rgb } from 'src/api/colors';

import { degrees } from 'src/api/rotations';

import {

RichTextFieldReadError,

ExceededMaxLengthError,

InvalidMaxLengthError,

} from 'src/api/errors';

import { ImageAlignment } from 'src/api/image/alignment';

import { TextAlignment } from 'src/api/text/alignment';

import {

PDFHexString,

PDFRef,

PDFStream,

PDFAcroText,

AcroTextFlags,

PDFWidgetAnnotation,

} from 'src/core';

import {

assertIs,

assertIsOneOf,

assertOrUndefined,

assertPositive,

assertRangeOrUndefined,

} from 'src/utils';

/**

* Represents a text field of a [[PDFForm]].

*

* [[PDFTextField]] fields are boxes that display text entered by the user. The

* purpose of a text field is to enable users to enter text or view text values

* in the document prefilled by software. Users can click on a text field and

* input text via their keyboard. Some text fields allow multiple lines of text

* to be entered (see [[PDFTextField.isMultiline]]).

*/

export default class PDFTextField extends PDFField {

/**

* > **NOTE:** You probably don't want to call this method directly. Instead,

* > consider using the [[PDFForm.getTextField]] method, which will create an

* > instance of [[PDFTextField]] for you.

*

* Create an instance of [[PDFTextField]] from an existing acroText and ref

*

* @param acroText The underlying `PDFAcroText` for this text field.

* @param ref The unique reference for this text field.

* @param doc The document to which this text field will belong.

*/

static of = (acroText: PDFAcroText, ref: PDFRef, doc: PDFDocument) =>

new PDFTextField(acroText, ref, doc);

/** The low-level PDFAcroText wrapped by this text field. */

readonly acroField: PDFAcroText;

private constructor(acroText: PDFAcroText, ref: PDFRef, doc: PDFDocument) {

super(acroText, ref, doc);

assertIs(acroText, 'acroText', [[PDFAcroText, 'PDFAcroText']]);

this.acroField = acroText;

}

/**

* Get the text that this field contains. This text is visible to users who

* view this field in a PDF reader.

*

* For example:

* ```js

* const textField = form.getTextField('some.text.field')

* const text = textField.getText()

* console.log('Text field contents:', text)

* ```

*

* Note that if this text field contains no underlying value, `undefined`

* will be returned. Text fields may also contain an underlying value that

* is simply an empty string (`''`). This detail is largely irrelevant for

* most applications. In general, you'll want to treat both cases the same

* way and simply consider the text field to be empty. In either case, the

* text field will appear empty to users when viewed in a PDF reader.

*

* An error will be thrown if this is a rich text field. `pdf-lib` does not

* support reading rich text fields. Nor do most PDF readers and writers.

* Rich text fields are based on XFA (XML Forms Architecture). Relatively few

* PDFs use rich text fields or XFA. Unlike PDF itself, XFA is not an ISO

* standard. XFA has been deprecated in PDF 2.0:

* * https://en.wikipedia.org/wiki/XFA

* * http://blog.pdfshareforms.com/pdf-2-0-release-bid-farewell-xfa-forms/

*

* @returns The text contained in this text field.

*/

getText(): string | undefined {

const value = this.acroField.getValue();

if (!value && this.isRichFormatted()) {

throw new RichTextFieldReadError(this.getName());

}

return value?.decodeText();

}

/**

* Set the text for this field. This operation is analogous to a human user

* clicking on the text field in a PDF reader and typing in text via their

* keyboard. This method will update the underlying state of the text field

* to indicate what text has been set. PDF libraries and readers will be able

* to extract these values from the saved document and determine what text

* was set.

*

* For example:

* ```js

* const textField = form.getTextField('best.superhero.text.field')

* textField.setText('One Punch Man')

* ```

*

* This method will mark this text field as dirty, causing its appearance

* streams to be updated when either [[PDFDocument.save]] or

* [[PDFForm.updateFieldAppearances]] is called. The updated streams will

* display the text this field contains inside the widgets of this text

* field.

*

* **IMPORTANT:** The default font used to update appearance streams is

* [[StandardFonts.Helvetica]]. Note that this is a WinAnsi font. This means

* that encoding errors will be thrown if this field contains text outside

* the WinAnsi character set (the latin alphabet).

*

* Embedding a custom font and passing it to

* [[PDFForm.updateFieldAppearances]] or [[PDFTextField.updateAppearances]]

* allows you to generate appearance streams with characters outside the

* latin alphabet (assuming the custom font supports them).

*

* If this is a rich text field, it will be converted to a standard text

* field in order to set the text. `pdf-lib` does not support writing rich

* text strings. Nor do most PDF readers and writers. See

* [[PDFTextField.getText]] for more information about rich text fields and

* their deprecation in PDF 2.0.

*

* @param text The text this field should contain.

*/

setText(text: string | undefined) {

assertOrUndefined(text, 'text', ['string']);

const maxLength = this.getMaxLength();

if (maxLength !== undefined && text && text.length > maxLength) {

throw new ExceededMaxLengthError(text.length, maxLength, this.getName());

}

this.markAsDirty();

this.disableRichFormatting();

if (text) {

this.acroField.setValue(PDFHexString.fromText(text));

} else {

this.acroField.removeValue();

}

}

/**

* Get the alignment for this text field. This value represents the

* justification of the text when it is displayed to the user in PDF readers.

* There are three possible alignments: left, center, and right. For example:

* ```js

* const textField = form.getTextField('some.text.field')

* const alignment = textField.getAlignment()

* if (alignment === TextAlignment.Left) console.log('Text is left justified')

* if (alignment === TextAlignment.Center) console.log('Text is centered')

* if (alignment === TextAlignment.Right) console.log('Text is right justified')

* ```

* @returns The alignment of this text field.

*/

getAlignment(): TextAlignment {

const quadding = this.acroField.getQuadding();

// prettier-ignore

return (

quadding === 0 ? TextAlignment.Left

: quadding === 1 ? TextAlignment.Center

: quadding === 2 ? TextAlignment.Right

: TextAlignment.Left

);

}

/**

* Set the alignment for this text field. This will determine the

* justification of the text when it is displayed to the user in PDF readers.

* There are three possible alignments: left, center, and right. For example:

* ```js

* const textField = form.getTextField('some.text.field')

*

* // Text will be left justified when displayed

* textField.setAlignment(TextAlignment.Left)

*

* // Text will be centered when displayed

* textField.setAlignment(TextAlignment.Center)

*

* // Text will be right justified when displayed

* textField.setAlignment(TextAlignment.Right)

* ```

* This method will mark this text field as dirty. See

* [[PDFTextField.setText]] for more details about what this means.

* @param alignment The alignment for this text field.

*/

setAlignment(alignment: TextAlignment) {

assertIsOneOf(alignment, 'alignment', TextAlignment);

this.markAsDirty();

this.acroField.setQuadding(alignment);

}

/**

* Get the maximum length of this field. This value represents the maximum

* number of characters that can be typed into this field by the user. If

* this field does not have a maximum length, `undefined` is returned.

* For example:

* ```js

* const textField = form.getTextField('some.text.field')

* const maxLength = textField.getMaxLength()

* if (maxLength === undefined) console.log('No max length')

* else console.log(`Max length is ${maxLength}`)

* ```

* @returns The maximum number of characters allowed in this field, or

* `undefined` if no limit exists.

*/

getMaxLength(): number | undefined {

return this.acroField.getMaxLength();

}

/**

* Set the maximum length of this field. This limits the number of characters

* that can be typed into this field by the user. This also limits the length

* of the string that can be passed to [[PDFTextField.setText]]. This limit

* can be removed by passing `undefined` as `maxLength`. For example:

* ```js

* const textField = form.getTextField('some.text.field')

*

* // Allow between 0 and 5 characters to be entered

* textField.setMaxLength(5)

*

* // Allow any number of characters to be entered

* textField.setMaxLength(undefined)

* ```

* This method will mark this text field as dirty. See

* [[PDFTextField.setText]] for more details about what this means.

* @param maxLength The maximum number of characters allowed in this field, or

* `undefined` to remove the limit.

*/

setMaxLength(maxLength?: number) {

assertRangeOrUndefined(maxLength, 'maxLength', 0, Number.MAX_SAFE_INTEGER);

this.markAsDirty();

if (maxLength === undefined) {

this.acroField.removeMaxLength();

} else {

const text = this.getText();

if (text && text.length > maxLength) {

throw new InvalidMaxLengthError(text.length, maxLength, this.getName());

}

this.acroField.setMaxLength(maxLength);

}

}

/**

* Remove the maximum length for this text field. This allows any number of

* characters to be typed into this field by the user. For example:

* ```js

* const textField = form.getTextField('some.text.field')

* textField.removeMaxLength()

* ```

* Calling this method is equivalent to passing `undefined` to

* [[PDFTextField.setMaxLength]].

*/

removeMaxLength() {

this.markAsDirty();

this.acroField.removeMaxLength();

}

/**

* Display an image inside the bounds of this text field's widgets. For example:

* ```js

* const pngImage = await pdfDoc.embedPng(...)

* const textField = form.getTextField('some.text.field')

* textField.setImage(pngImage)

* ```

* This will update the appearances streams for each of this text field's widgets.

* @param image The image that should be displayed.

*/

setImage(image: PDFImage) {

const fieldAlignment = this.getAlignment();

// prettier-ignore

const alignment =

fieldAlignment === TextAlignment.Center ? ImageAlignment.Center

: fieldAlignment === TextAlignment.Right ? ImageAlignment.Right

: ImageAlignment.Left;

const widgets = this.acroField.getWidgets();

for (let idx = 0, len = widgets.length; idx < len; idx++) {

const widget = widgets[idx];

const streamRef = this.createImageAppearanceStream(

widget,

image,

alignment,

);

this.updateWidgetAppearances(widget, { normal: streamRef });

}

this.markAsClean();

}

/**

* Set the font size for this field. Larger font sizes will result in larger

* text being displayed when PDF readers render this text field. Font sizes

* may be integer or floating point numbers. Supplying a negative font size

* will cause this method to throw an error.

*

* For example:

* ```js

* const textField = form.getTextField('some.text.field')

* textField.setFontSize(4)

* textField.setFontSize(15.7)

* ```

*

* > This method depends upon the existence of a default appearance

* > (`/DA`) string. If this field does not have a default appearance string,

* > or that string does not contain a font size (via the `Tf` operator),

* > then this method will throw an error.

*

* @param fontSize The font size to be used when rendering text in this field.

*/

setFontSize(fontSize: number) {

assertPositive(fontSize, 'fontSize');

this.acroField.setFontSize(fontSize);

this.markAsDirty();

}

/**

* Returns `true` if each line of text is shown on a new line when this

* field is displayed in a PDF reader. The alternative is that all lines of

* text are merged onto a single line when displayed. See

* [[PDFTextField.enableMultiline]] and [[PDFTextField.disableMultiline]].

* For example:

* ```js

* const textField = form.getTextField('some.text.field')

* if (textField.isMultiline()) console.log('Multiline is enabled')

* ```

* @returns Whether or not this is a multiline text field.

*/

isMultiline(): boolean {

return this.acroField.hasFlag(AcroTextFlags.Multiline);

}

/**

* Display each line of text on a new line when this field is displayed in a

* PDF reader. For example:

* ```js

* const textField = form.getTextField('some.text.field')

* textField.enableMultiline()

* ```

* This method will mark this text field as dirty. See

* [[PDFTextField.setText]] for more details about what this means.

*/

enableMultiline() {

this.markAsDirty();

this.acroField.setFlagTo(AcroTextFlags.Multiline, true);

}

/**

* Display each line of text on the same line when this field is displayed

* in a PDF reader. For example:

* ```js

* const textField = form.getTextField('some.text.field')

* textField.disableMultiline()

* ```

* This method will mark this text field as dirty. See

* [[PDFTextField.setText]] for more details about what this means.

*/

disableMultiline() {

this.markAsDirty();

this.acroField.setFlagTo(AcroTextFlags.Multiline, false);

}

/**

* Returns `true` if this is a password text field. This means that the field

* is intended for storing a secure password. See

* [[PDFTextField.enablePassword]] and [[PDFTextField.disablePassword]].

* For example:

* ```js

* const textField = form.getTextField('some.text.field')

* if (textField.isPassword()) console.log('Password is enabled')

* ```

* @returns Whether or not this is a password text field.

*/

isPassword(): boolean {

return this.acroField.hasFlag(AcroTextFlags.Password);

}

/**

* Indicate that this text field is intended for storing a secure password.

* For example:

* ```js

* const textField = form.getTextField('some.text.field')

* textField.enablePassword()

* ```

* Values entered into password text fields should not be displayed on the

* screen by PDF readers. Most PDF readers will display the value as

* asterisks or bullets. PDF readers should never store values entered by the

* user into password text fields. Similarly, applications should not

* write data to a password text field.

*

* **Please note that this method does not cause entered values to be

* encrypted or secured in any way! It simply sets a flag that PDF software

* and readers can access to determine the _purpose_ of this field.**

*/

enablePassword() {

this.acroField.setFlagTo(AcroTextFlags.Password, true);

}

/**

* Indicate that this text field is **not** intended for storing a secure

* password. For example:

* ```js

* const textField = form.getTextField('some.text.field')

* textField.disablePassword()

* ```

*/

disablePassword() {

this.acroField.setFlagTo(AcroTextFlags.Password, false);

}

/**

* Returns `true` if the contents of this text field represent a file path.

* See [[PDFTextField.enableFileSelection]] and

* [[PDFTextField.disableFileSelection]]. For example:

* ```js

* const textField = form.getTextField('some.text.field')

* if (textField.isFileSelector()) console.log('Is a file selector')

* ```

* @returns Whether or not this field should contain file paths.

*/

isFileSelector(): boolean {

return this.acroField.hasFlag(AcroTextFlags.FileSelect);

}

/**

* Indicate that this text field is intended to store a file path. The

* contents of the file stored at that path should be submitted as the value

* of the field. For example:

* ```js

* const textField = form.getTextField('some.text.field')

* textField.enableFileSelection()

* ```

*/

enableFileSelection() {

this.acroField.setFlagTo(AcroTextFlags.FileSelect, true);

}

/**

* Indicate that this text field is **not** intended to store a file path.

* For example:

* ```js

* const textField = form.getTextField('some.text.field')

* textField.disableFileSelection()

* ```

*/

disableFileSelection() {

this.acroField.setFlagTo(AcroTextFlags.FileSelect, false);

}

/**

* Returns `true` if the text entered in this field should be spell checked

* by PDF readers. See [[PDFTextField.enableSpellChecking]] and

* [[PDFTextField.disableSpellChecking]]. For example:

* ```js

* const textField = form.getTextField('some.text.field')

* if (textField.isSpellChecked()) console.log('Spell checking is enabled')

* ```

* @returns Whether or not this field should be spell checked.

*/

isSpellChecked(): boolean {

return !this.acroField.hasFlag(AcroTextFlags.DoNotSpellCheck);

}

/**

* Allow PDF readers to spell check the text entered in this field.

* For example:

* ```js

* const textField = form.getTextField('some.text.field')

* textField.enableSpellChecking()

* ```

*/

enableSpellChecking() {

this.acroField.setFlagTo(AcroTextFlags.DoNotSpellCheck, false);

}

/**

* Do not allow PDF readers to spell check the text entered in this field.

* For example:

* ```js

* const textField = form.getTextField('some.text.field')

* textField.disableSpellChecking()

* ```

*/

disableSpellChecking() {

this.acroField.setFlagTo(AcroTextFlags.DoNotSpellCheck, true);

}

/**

* Returns `true` if PDF readers should allow the user to scroll the text

* field when its contents do not fit within the field's view bounds. See

* [[PDFTextField.enableScrolling]] and [[PDFTextField.disableScrolling]].

* For example:

* ```js

* const textField = form.getTextField('some.text.field')

* if (textField.isScrollable()) console.log('Scrolling is enabled')

* ```

* @returns Whether or not the field is scrollable in PDF readers.

*/

isScrollable(): boolean {

return !this.acroField.hasFlag(AcroTextFlags.DoNotScroll);

}

/**

* Allow PDF readers to present a scroll bar to the user when the contents

* of this text field do not fit within its view bounds. For example:

* ```js

* const textField = form.getTextField('some.text.field')

* textField.enableScrolling()

* ```

* A horizontal scroll bar should be shown for singleline fields. A vertical

* scroll bar should be shown for multiline fields.

*/

enableScrolling() {

this.acroField.setFlagTo(AcroTextFlags.DoNotScroll, false);

}

/**

* Do not allow PDF readers to present a scroll bar to the user when the

* contents of this text field do not fit within its view bounds. For example:

* ```js

* const textField = form.getTextField('some.text.field')

* textField.disableScrolling()

* ```

*/

disableScrolling() {

this.acroField.setFlagTo(AcroTextFlags.DoNotScroll, true);

}

/**

* Returns `true` if this is a combed text field. This means that the field

* is split into `n` equal size cells with one character in each (where `n`

* is equal to the max length of the text field). The result is that all

* characters in this field are displayed an equal distance apart from one

* another. See [[PDFTextField.enableCombing]] and

* [[PDFTextField.disableCombing]]. For example:

* ```js

* const textField = form.getTextField('some.text.field')

* if (textField.isCombed()) console.log('Combing is enabled')

* ```

* Note that in order for a text field to be combed, the following must be

* true (in addition to enabling combing):

* * It must not be a multiline field (see [[PDFTextField.isMultiline]])

* * It must not be a password field (see [[PDFTextField.isPassword]])

* * It must not be a file selector field (see [[PDFTextField.isFileSelector]])

* * It must have a max length defined (see [[PDFTextField.setMaxLength]])

* @returns Whether or not this field is combed.

*/

isCombed(): boolean {

return (

this.acroField.hasFlag(AcroTextFlags.Comb) &&

!this.isMultiline() &&

!this.isPassword() &&

!this.isFileSelector() &&

this.getMaxLength() !== undefined

);

}

/**

* Split this field into `n` equal size cells with one character in each

* (where `n` is equal to the max length of the text field). This will cause

* all characters in the field to be displayed an equal distance apart from

* one another. For example:

* ```js

* const textField = form.getTextField('some.text.field')

* textField.enableCombing()

* ```

*

* In addition to calling this method, text fields must have a max length

* defined in order to be combed (see [[PDFTextField.setMaxLength]]).

*

* This method will also call the following three methods internally:

* * [[PDFTextField.disableMultiline]]

* * [[PDFTextField.disablePassword]]

* * [[PDFTextField.disableFileSelection]]

*

* This method will mark this text field as dirty. See

* [[PDFTextField.setText]] for more details about what this means.

*/

enableCombing() {

if (this.getMaxLength() === undefined) {

const msg = `PDFTextFields must have a max length in order to be combed`;

console.warn(msg);

}

this.markAsDirty();

this.disableMultiline();

this.disablePassword();

this.disableFileSelection();

this.acroField.setFlagTo(AcroTextFlags.Comb, true);

}

/**

* Turn off combing for this text field. For example:

* ```js

* const textField = form.getTextField('some.text.field')

* textField.disableCombing()

* ```

* See [[PDFTextField.isCombed]] and [[PDFTextField.enableCombing]] for more

* information about what combing is.

*

* This method will mark this text field as dirty. See

* [[PDFTextField.setText]] for more details about what this means.

*/

disableCombing() {

this.markAsDirty();

this.acroField.setFlagTo(AcroTextFlags.Comb, false);

}

/**

* Returns `true` if this text field contains rich text. See

* [[PDFTextField.enableRichFormatting]] and

* [[PDFTextField.disableRichFormatting]]. For example:

* ```js

* const textField = form.getTextField('some.text.field')

* if (textField.isRichFormatted()) console.log('Rich formatting enabled')

* ```

* @returns Whether or not this field contains rich text.

*/

isRichFormatted(): boolean {

return this.acroField.hasFlag(AcroTextFlags.RichText);

}

/**

* Indicate that this field contains XFA data - or rich text. For example:

* ```js

* const textField = form.getTextField('some.text.field')

* textField.enableRichFormatting()

* ```

* Note that `pdf-lib` does not support reading or writing rich text fields.

* Nor do most PDF readers and writers. Rich text fields are based on XFA

* (XML Forms Architecture). Relatively few PDFs use rich text fields or XFA.

* Unlike PDF itself, XFA is not an ISO standard. XFA has been deprecated in

* PDF 2.0:

* * https://en.wikipedia.org/wiki/XFA

* * http://blog.pdfshareforms.com/pdf-2-0-release-bid-farewell-xfa-forms/

*/

enableRichFormatting() {

this.acroField.setFlagTo(AcroTextFlags.RichText, true);

}

/**

* Indicate that this is a standard text field that does not XFA data (rich

* text). For example:

* ```js

* const textField = form.getTextField('some.text.field')

* textField.disableRichFormatting()

* ```

*/

disableRichFormatting() {

this.acroField.setFlagTo(AcroTextFlags.RichText, false);

}

/**

* Show this text field on the specified page. For example:

* ```js

* const ubuntuFont = await pdfDoc.embedFont(ubuntuFontBytes)

* const page = pdfDoc.addPage()

*

* const form = pdfDoc.getForm()

* const textField = form.createTextField('best.gundam')

* textField.setText('Exia')

*

* textField.addToPage(page, {

* x: 50,

* y: 75,

* width: 200,

* height: 100,

* textColor: rgb(1, 0, 0),

* backgroundColor: rgb(0, 1, 0),

* borderColor: rgb(0, 0, 1),

* borderWidth: 2,

* rotate: degrees(90),

* font: ubuntuFont,

* })

* ```

* This will create a new widget for this text field.

* @param page The page to which this text field widget should be added.

* @param options The options to be used when adding this text field widget.

*/

addToPage(page: PDFPage, options?: FieldAppearanceOptions) {

assertIs(page, 'page', [[PDFPage, 'PDFPage']]);

assertFieldAppearanceOptions(options);

if (!options) options = {};

if (!('textColor' in options)) options.textColor = rgb(0, 0, 0);

if (!('backgroundColor' in options)) options.backgroundColor = rgb(1, 1, 1);

if (!('borderColor' in options)) options.borderColor = rgb(0, 0, 0);

if (!('borderWidth' in options)) options.borderWidth = 1;

// Create a widget for this text field

const widget = this.createWidget({

x: options.x ?? 0,

y: options.y ?? 0,

width: options.width ?? 200,

height: options.height ?? 50,

textColor: options.textColor,

backgroundColor: options.backgroundColor,

borderColor: options.borderColor,

borderWidth: options.borderWidth ?? 0,

rotate: options.rotate ?? degrees(0),

hidden: options.hidden,

page: page.ref,

});

const widgetRef = this.doc.context.register(widget.dict);

// Add widget to this field

this.acroField.addWidget(widgetRef);

// Set appearance streams for widget

const font = options.font ?? this.doc.getForm().getDefaultFont();

this.updateWidgetAppearance(widget, font);

// Add widget to the given page

page.node.addAnnot(widgetRef);

}

/**

* Returns `true` if this text field has been marked as dirty, or if any of

* this text field's widgets do not have an appearance stream. For example:

* ```js

* const textField = form.getTextField('some.text.field')

* if (textField.needsAppearancesUpdate()) console.log('Needs update')

* ```

* @returns Whether or not this text field needs an appearance update.

*/

needsAppearancesUpdate(): boolean {

if (this.isDirty()) return true;

const widgets = this.acroField.getWidgets();

for (let idx = 0, len = widgets.length; idx < len; idx++) {

const widget = widgets[idx];

const hasAppearances =

widget.getAppearances()?.normal instanceof PDFStream;

if (!hasAppearances) return true;

}

return false;

}

/**

* Update the appearance streams for each of this text field's widgets using

* the default appearance provider for text fields. For example:

* ```js

* const helvetica = await pdfDoc.embedFont(StandardFonts.Helvetica)

* const textField = form.getTextField('some.text.field')

* textField.defaultUpdateAppearances(helvetica)

* ```

* @param font The font to be used for creating the appearance streams.

*/

defaultUpdateAppearances(font: PDFFont) {

assertIs(font, 'font', [[PDFFont, 'PDFFont']]);

this.updateAppearances(font);

}

/**

* Update the appearance streams for each of this text field's widgets using

* the given appearance provider. If no `provider` is passed, the default

* appearance provider for text fields will be used. For example:

* ```js

* const helvetica = await pdfDoc.embedFont(StandardFonts.Helvetica)

* const textField = form.getTextField('some.text.field')

* textField.updateAppearances(helvetica, (field, widget, font) => {

* ...

* return drawTextField(...)

* })

* ```

* @param font The font to be used for creating the appearance streams.

* @param provider Optionally, the appearance provider to be used for

* generating the contents of the appearance streams.

*/

updateAppearances(

font: PDFFont,

provider?: AppearanceProviderFor<PDFTextField>,

) {

assertIs(font, 'font', [[PDFFont, 'PDFFont']]);

assertOrUndefined(provider, 'provider', [Function]);

const widgets = this.acroField.getWidgets();

for (let idx = 0, len = widgets.length; idx < len; idx++) {

const widget = widgets[idx];

this.updateWidgetAppearance(widget, font, provider);

}

this.markAsClean();

}

private updateWidgetAppearance(

widget: PDFWidgetAnnotation,

font: PDFFont,

provider?: AppearanceProviderFor<PDFTextField>,

) {

const apProvider = provider ?? defaultTextFieldAppearanceProvider;

const appearances = normalizeAppearance(apProvider(this, widget, font));

this.updateWidgetAppearanceWithFont(widget, font, appearances);

}

}