BasicTextField

dependencies {
   implementation("androidx.compose.foundation:foundation:1.7.0-beta04")
}

@Composable
@Suppress("ComposableLambdaParameterPosition"
fun BasicTextField(
    state: TextFieldState,
    modifier: Modifier = Modifier,
    enabled: Boolean = true,
    readOnly: Boolean = false,
    inputTransformation: InputTransformation? = null,
    textStyle: TextStyle = TextStyle.Default,
    keyboardOptions: KeyboardOptions = KeyboardOptions.Default,
    onKeyboardAction: KeyboardActionHandler? = null,
    lineLimits: TextFieldLineLimits = TextFieldLineLimits.Default,
    onTextLayout: (Density.(getResult: () -> TextLayoutResult?) -> Unit)? = null,
    interactionSource: MutableInteractionSource? = null,
    cursorBrush: Brush = BasicTextFieldDefaults.CursorBrush,
    outputTransformation: OutputTransformation? = null,
    decorator: TextFieldDecorator? = null,
    scrollState: ScrollState = rememberScrollState(),
    // Last parameter must not be a function unless it's intended to be commonly used as a trailing
    // lambda.
)

@Composable
fun BasicTextField(
    value: String,
    onValueChange: (String) -> Unit,
    modifier: Modifier = Modifier,
    enabled: Boolean = true,
    readOnly: Boolean = false,
    textStyle: TextStyle = TextStyle.Default,
    keyboardOptions: KeyboardOptions = KeyboardOptions.Default,
    keyboardActions: KeyboardActions = KeyboardActions.Default,
    singleLine: Boolean = false,
    maxLines: Int = if (singleLine) 1 else Int.MAX_VALUE,
    minLines: Int = 1,
    visualTransformation: VisualTransformation = VisualTransformation.None,
    onTextLayout: (TextLayoutResult) -> Unit = {},
    interactionSource: MutableInteractionSource? = null,
    cursorBrush: Brush = SolidColor(Color.Black),
    decorationBox: @Composable (innerTextField: @Composable () -> Unit) -> Unit =
        @Composable { innerTextField -> innerTextField() }
)

@Composable
fun BasicTextField(
    value: TextFieldValue,
    onValueChange: (TextFieldValue) -> Unit,
    modifier: Modifier = Modifier,
    enabled: Boolean = true,
    readOnly: Boolean = false,
    textStyle: TextStyle = TextStyle.Default,
    keyboardOptions: KeyboardOptions = KeyboardOptions.Default,
    keyboardActions: KeyboardActions = KeyboardActions.Default,
    singleLine: Boolean = false,
    maxLines: Int = if (singleLine) 1 else Int.MAX_VALUE,
    minLines: Int = 1,
    visualTransformation: VisualTransformation = VisualTransformation.None,
    onTextLayout: (TextLayoutResult) -> Unit = {},
    interactionSource: MutableInteractionSource? = null,
    cursorBrush: Brush = SolidColor(Color.Black),
    decorationBox: @Composable (innerTextField: @Composable () -> Unit) -> Unit =
        @Composable { innerTextField -> innerTextField() }
)

@Composable
@Deprecated("Maintained for binary compatibility", level = DeprecationLevel.HIDDEN
fun BasicTextField(
    value: TextFieldValue,
    onValueChange: (TextFieldValue) -> Unit,
    modifier: Modifier = Modifier,
    enabled: Boolean = true,
    readOnly: Boolean = false,
    textStyle: TextStyle = TextStyle.Default,
    keyboardOptions: KeyboardOptions = KeyboardOptions.Default,
    keyboardActions: KeyboardActions = KeyboardActions.Default,
    singleLine: Boolean = false,
    maxLines: Int = Int.MAX_VALUE,
    visualTransformation: VisualTransformation = VisualTransformation.None,
    onTextLayout: (TextLayoutResult) -> Unit = {},
    interactionSource: MutableInteractionSource = remember { MutableInteractionSource() },
    cursorBrush: Brush = SolidColor(Color.Black),
    decorationBox: @Composable (innerTextField: @Composable () -> Unit) -> Unit =
        @Composable { innerTextField -> innerTextField() }
)

@Composable
@Deprecated("Maintained for binary compatibility", level = DeprecationLevel.HIDDEN
fun BasicTextField(
    value: String,
    onValueChange: (String) -> Unit,
    modifier: Modifier = Modifier,
    enabled: Boolean = true,
    readOnly: Boolean = false,
    textStyle: TextStyle = TextStyle.Default,
    keyboardOptions: KeyboardOptions = KeyboardOptions.Default,
    keyboardActions: KeyboardActions = KeyboardActions.Default,
    singleLine: Boolean = false,
    maxLines: Int = Int.MAX_VALUE,
    visualTransformation: VisualTransformation = VisualTransformation.None,
    onTextLayout: (TextLayoutResult) -> Unit = {},
    interactionSource: MutableInteractionSource = remember { MutableInteractionSource() },
    cursorBrush: Brush = SolidColor(Color.Black),
    decorationBox: @Composable (innerTextField: @Composable () -> Unit) -> Unit =
        @Composable { innerTextField -> innerTextField() }
)

@Composable
@Sampled
fun BasicTextFieldDecoratorSample() {
    // Demonstrates how to use the decorator API on BasicTextField
    val state = rememberTextFieldState("Hello, World!")
    BasicTextField(
        state = state,
        decorator = { innerTextField ->
            // Because the decorator is used, the whole Row gets the same behaviour as the internal
            // input field would have otherwise. For example, there is no need to add a
            // `Modifier.clickable` to the Row anymore to bring the text field into focus when user
            // taps on a larger text field area which includes paddings and the icon areas.
            Row(
                Modifier
                    .background(Color.LightGray, RoundedCornerShape(percent = 30))
                    .padding(16.dp)
            ) {
                Icon(Icons.Default.MailOutline, contentDescription = "Mail Icon")
                Spacer(Modifier.width(16.dp))
                innerTextField()
            }
        }
    )
}

@Composable
@Sampled
fun BasicTextFieldCustomInputTransformationSample() {
    // Demonstrates how to create a custom and relatively complex InputTransformation.
    val state = remember { TextFieldState() }
    BasicTextField(state, inputTransformation = {
        // A filter that always places newly-input text at the start of the string, after a
        // prompt character, like a shell.
        val promptChar = '>'

        fun CharSequence.countPrefix(char: Char): Int {
            var i = 0
            while (i < length && get(i) == char) i++
            return i
        }

        // Step one: Figure out the insertion point.
        val newPromptChars = asCharSequence().countPrefix(promptChar)
        val insertionPoint = if (newPromptChars == 0) 0 else 1

        // Step two: Ensure text is placed at the insertion point.
        if (changes.changeCount == 1) {
            val insertedRange = changes.getRange(0)
            val replacedRange = changes.getOriginalRange(0)
            if (!replacedRange.collapsed && insertedRange.collapsed) {
                // Text was deleted, delete forwards from insertion point.
                delete(insertionPoint, insertionPoint + replacedRange.length)
            }
        }
        // Else text was replaced or there were multiple changes - don't handle.

        // Step three: Ensure the prompt character is there.
        if (newPromptChars == 0) {
            insert(0, ">")
        }

        // Step four: Ensure the cursor is ready for the next input.
        placeCursorAfterCharAt(0)
    })
}

@Composable
@Sampled
fun BasicTextFieldWithValueOnValueChangeSample() {
    var text by remember { mutableStateOf("") }
    // A reference implementation that demonstrates how to create a TextField with the legacy
    // state hoisting design around `BasicTextField(TextFieldState)`
    StringTextField(
        value = text,
        onValueChange = { text = it }
    )
}

@Composable
@Sampled
fun BasicTextFieldWithStringSample() {
    var value by rememberSaveable { mutableStateOf("initial value") }
    BasicTextField(
        value = value,
        onValueChange = {
            // it is crucial that the update is fed back into BasicTextField in order to
            // see updates on the text
            value = it
        }
    )
}

@Composable
@Sampled
fun PlaceholderBasicTextFieldSample() {
    var value by rememberSaveable { mutableStateOf("initial value") }
    Box {
        BasicTextField(
            value = value,
            onValueChange = { value = it }
        )
        if (value.isEmpty()) {
            Text(text = "Placeholder")
        }
    }
}

@Composable
@Sampled
fun TextFieldWithIconSample() {
    var value by rememberSaveable { mutableStateOf("initial value") }
    BasicTextField(
        value = value,
        onValueChange = { value = it },
        decorationBox = { innerTextField ->
            // Because the decorationBox is used, the whole Row gets the same behaviour as the
            // internal input field would have otherwise. For example, there is no need to add a
            // Modifier.clickable to the Row anymore to bring the text field into focus when user
            // taps on a larger text field area which includes paddings and the icon areas.
            Row(
                Modifier
                    .background(Color.LightGray, RoundedCornerShape(percent = 30))
                    .padding(16.dp)
            ) {
                Icon(Icons.Default.MailOutline, contentDescription = null)
                Spacer(Modifier.width(16.dp))
                innerTextField()
            }
        }
    )
}

@Composable
@Sampled
fun CreditCardSample() {
    /** The offset translator used for credit card input field */
    val creditCardOffsetTranslator = object : OffsetMapping {
        override fun originalToTransformed(offset: Int): Int {
            return when {
                offset < 4 -> offset
                offset < 8 -> offset + 1
                offset < 12 -> offset + 2
                offset {'<='} 16 -> offset + 3
                else -> 19
            }
        }

        override fun transformedToOriginal(offset: Int): Int {
            return when {
                offset {'<='} 4 -> offset
                offset {'<='} 9 -> offset - 1
                offset {'<='} 14 -> offset - 2
                offset {'<='} 19 -> offset - 3
                else -> 16
            }
        }
    }

    /**
     * Converts up to 16 digits to hyphen connected 4 digits string. For example,
     * "1234567890123456" will be shown as "1234-5678-9012-3456"
     */
    val creditCardTransformation = VisualTransformation { text ->
        val trimmedText = if (text.text.length > 16) text.text.substring(0..15) else text.text
        var transformedText = ""
        trimmedText.forEachIndexed { index, char ->
            transformedText += char
            if ((index + 1) % 4 == 0 && index != 15) transformedText += "-"
        }
        TransformedText(AnnotatedString(transformedText), creditCardOffsetTranslator)
    }

    var text by rememberSaveable { mutableStateOf("") }
    BasicTextField(
        value = text,
        onValueChange = { input ->
            if (input.length {'<='} 16 && input.none { !it.isDigit() }) {
                text = input
            }
        },
        modifier = Modifier.size(170.dp, 30.dp).background(Color.LightGray).wrapContentSize(),
        singleLine = true,
        keyboardOptions = KeyboardOptions(keyboardType = KeyboardType.Number),
        visualTransformation = creditCardTransformation
    )
}

@Composable
@Sampled
fun BasicTextFieldSample() {
    var value by rememberSaveable(stateSaver = TextFieldValue.Saver) {
        mutableStateOf(TextFieldValue())
    }
    BasicTextField(
        value = value,
        onValueChange = {
            // it is crucial that the update is fed back into BasicTextField in order to
            // see updates on the text
            value = it
        }
    )
}