react-native-ui-lib/src/utils/textUtils.js

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import _toLower from "lodash/toLower";
import _isEmpty from "lodash/isEmpty";
function getPartsByHighlight(targetString = '', highlightString) {
  if (!Array.isArray(highlightString)) {
    const stringValue = getHighlightStringValue(highlightString);
    if (_isEmpty(stringValue.trim())) {
      return [{
        string: targetString,
        shouldHighlight: false
      }];
    }
    return getTextPartsByHighlight(targetString, highlightString);
  } else {
    return getArrayPartsByHighlight(targetString, highlightString);
  }
}
function getHighlightStringValue(highlightString) {
  if (isHighlightStringProps(highlightString)) {
    return highlightString.string;
  } else {
    return highlightString;
  }
}
function isHighlightStringProps(highlightString) {
  return typeof highlightString !== 'string';
}
function getTextPartsByHighlight(targetString = '', highlightString = '') {
  const stringValue = getHighlightStringValue(highlightString);
  if (stringValue === '') {
    return [{
      string: targetString,
      shouldHighlight: false
    }];
  }
  const textParts = [];
  let highlightIndex;
  do {
    highlightIndex = targetString.toLowerCase().indexOf(stringValue.toLowerCase());
    if (highlightIndex !== -1) {
      if (highlightIndex > 0) {
        textParts.push({
          string: targetString.substring(0, highlightIndex),
          shouldHighlight: false
        });
      }
      const highlightStringProps = isHighlightStringProps(highlightString) ? {
        onPress: highlightString.onPress,
        style: highlightString.style,
        testID: highlightString.testID
      } : {};
      textParts.push({
        string: targetString.substr(highlightIndex, stringValue.length),
        shouldHighlight: true,
        ...highlightStringProps
      });
      targetString = targetString.substr(highlightIndex + stringValue.length);
    } else {
      textParts.push({
        string: targetString,
        shouldHighlight: false
      });
    }
  } while (highlightIndex !== -1 && targetString.length > 0);
  return textParts;
}
function getArrayPartsByHighlight(targetString = '', highlightString = ['']) {
  const target = _toLower(targetString);
  const indices = [];
  let index = 0;
  let lastWordLength = 0;
  for (let j = 0; j < highlightString.length; j++) {
    const stringValue = getHighlightStringValue(highlightString[j]);
    const word = _toLower(stringValue);
    if (word.length === 0) {
      break;
    }
    const targetSuffix = target.substring(index + lastWordLength);
    const i = targetSuffix.indexOf(word);
    if (i >= 0) {
      const newIndex = index + lastWordLength + i;
      indices.push({
        start: index + lastWordLength + i,
        end: index + lastWordLength + i + word.length,
        highlightStringIndex: j
      });
      index = newIndex;
      lastWordLength = word.length;
    } else {
      break;
    }
  }
  const textParts = [];
  for (let k = 0; k < indices.length; k++) {
    if (k === 0 && indices[k].start !== 0) {
      textParts.push({
        string: targetString.substring(0, indices[k].start),
        shouldHighlight: false
      });
    }
    const currentHighlightString = highlightString[indices[k].highlightStringIndex];
    const highlightStringProps = isHighlightStringProps(currentHighlightString) ? {
      onPress: currentHighlightString.onPress,
      style: currentHighlightString.style,
      testID: currentHighlightString.testID
    } : {};
    textParts.push({
      string: targetString.substring(indices[k].start, indices[k].end),
      shouldHighlight: true,
      ...highlightStringProps
    });
    if (indices[k].end < targetString.length) {
      if (k === indices.length - 1) {
        textParts.push({
          string: targetString.substring(indices[k].end),
          shouldHighlight: false
        });
      } else {
        textParts.push({
          string: targetString.substring(indices[k].end, indices[k + 1].start),
          shouldHighlight: false
        });
      }
    }
  }
  if (textParts.length === 0) {
    textParts.push({
      string: targetString,
      shouldHighlight: false
    });
  }
  return textParts;
}
export { getPartsByHighlight, getTextPartsByHighlight, getArrayPartsByHighlight };