/**
 * Concatenates two arrays faster than the array spread operator.
 */
const concatArrays = (array1, array2) => {
  // Pre-allocate for better V8 optimization
  const combinedArray = new Array(array1.length + array2.length);
  for (let i = 0; i < array1.length; i++) {
    combinedArray[i] = array1[i];
  }
  for (let i = 0; i < array2.length; i++) {
    combinedArray[array1.length + i] = array2[i];
  }
  return combinedArray;
};

// Factory function ensures consistent object shapes
const createClassValidatorObject = (classGroupId, validator) => ({
  classGroupId,
  validator
});
// Factory ensures consistent ClassPartObject shape
const createClassPartObject = (nextPart = new Map(), validators = null, classGroupId) => ({
  nextPart,
  validators,
  classGroupId
});
const CLASS_PART_SEPARATOR = '-';
const EMPTY_CONFLICTS = [];
// I use two dots here because one dot is used as prefix for class groups in plugins
const ARBITRARY_PROPERTY_PREFIX = 'arbitrary..';
const createClassGroupUtils = config => {
  const classMap = createClassMap(config);
  const {
    conflictingClassGroups,
    conflictingClassGroupModifiers
  } = config;
  const getClassGroupId = className => {
    if (className.startsWith('[') && className.endsWith(']')) {
      return getGroupIdForArbitraryProperty(className);
    }
    const classParts = className.split(CLASS_PART_SEPARATOR);
    // Classes like `-inset-1` produce an empty string as first classPart. We assume that classes for negative values are used correctly and skip it.
    const startIndex = classParts[0] === '' && classParts.length > 1 ? 1 : 0;
    return getGroupRecursive(classParts, startIndex, classMap);
  };
  const getConflictingClassGroupIds = (classGroupId, hasPostfixModifier) => {
    if (hasPostfixModifier) {
      const modifierConflicts = conflictingClassGroupModifiers[classGroupId];
      const baseConflicts = conflictingClassGroups[classGroupId];
      if (modifierConflicts) {
        if (baseConflicts) {
          // Merge base conflicts with modifier conflicts
          return concatArrays(baseConflicts, modifierConflicts);
        }
        // Only modifier conflicts
        return modifierConflicts;
      }
      // Fall back to without postfix if no modifier conflicts
      return baseConflicts || EMPTY_CONFLICTS;
    }
    return conflictingClassGroups[classGroupId] || EMPTY_CONFLICTS;
  };
  return {
    getClassGroupId,
    getConflictingClassGroupIds
  };
};
const getGroupRecursive = (classParts, startIndex, classPartObject) => {
  const classPathsLength = classParts.length - startIndex;
  if (classPathsLength === 0) {
    return classPartObject.classGroupId;
  }
  const currentClassPart = classParts[startIndex];
  const nextClassPartObject = classPartObject.nextPart.get(currentClassPart);
  if (nextClassPartObject) {
    const result = getGroupRecursive(classParts, startIndex + 1, nextClassPartObject);
    if (result) return result;
  }
  const validators = classPartObject.validators;
  if (validators === null) {
    return undefined;
  }
  // Build classRest string efficiently by joining from startIndex onwards
  const classRest = startIndex === 0 ? classParts.join(CLASS_PART_SEPARATOR) : classParts.slice(startIndex).join(CLASS_PART_SEPARATOR);
  const validatorsLength = validators.length;
  for (let i = 0; i < validatorsLength; i++) {
    const validatorObj = validators[i];
    if (validatorObj.validator(classRest)) {
      return validatorObj.classGroupId;
    }
  }
  return undefined;
};
/**
 * Get the class group ID for an arbitrary property.
 *
 * @param className - The class name to get the group ID for. Is expected to be string starting with `[` and ending with `]`.
 */
const getGroupIdForArbitraryProperty = className => className.slice(1, -1).indexOf(':') === -1 ? undefined : (() => {
  const content = className.slice(1, -1);
  const colonIndex = content.indexOf(':');
  const property = content.slice(0, colonIndex);
  return property ? ARBITRARY_PROPERTY_PREFIX + property : undefined;
})();
/**
 * Exported for testing only
 */
const createClassMap = config => {
  const {
    theme,
    classGroups
  } = config;
  return processClassGroups(classGroups, theme);
};
// Split into separate functions to maintain monomorphic call sites
const processClassGroups = (classGroups, theme) => {
  const classMap = createClassPartObject();
  for (const classGroupId in classGroups) {
    const group = classGroups[classGroupId];
    processClassesRecursively(group, classMap, classGroupId, theme);
  }
  return classMap;
};
const processClassesRecursively = (classGroup, classPartObject, classGroupId, theme) => {
  const len = classGroup.length;
  for (let i = 0; i < len; i++) {
    const classDefinition = classGroup[i];
    processClassDefinition(classDefinition, classPartObject, classGroupId, theme);
  }
};
// Split into separate functions for each type to maintain monomorphic call sites
const processClassDefinition = (classDefinition, classPartObject, classGroupId, theme) => {
  if (typeof classDefinition === 'string') {
    processStringDefinition(classDefinition, classPartObject, classGroupId);
    return;
  }
  if (typeof classDefinition === 'function') {
    processFunctionDefinition(classDefinition, classPartObject, classGroupId, theme);
    return;
  }
  processObjectDefinition(classDefinition, classPartObject, classGroupId, theme);
};
const processStringDefinition = (classDefinition, classPartObject, classGroupId) => {
  const classPartObjectToEdit = classDefinition === '' ? classPartObject : getPart(classPartObject, classDefinition);
  classPartObjectToEdit.classGroupId = classGroupId;
};
const processFunctionDefinition = (classDefinition, classPartObject, classGroupId, theme) => {
  if (isThemeGetter(classDefinition)) {
    processClassesRecursively(classDefinition(theme), classPartObject, classGroupId, theme);
    return;
  }
  if (classPartObject.validators === null) {
    classPartObject.validators = [];
  }
  classPartObject.validators.push(createClassValidatorObject(classGroupId, classDefinition));
};
const processObjectDefinition = (classDefinition, classPartObject, classGroupId, theme) => {
  const entries = Object.entries(classDefinition);
  const len = entries.length;
  for (let i = 0; i < len; i++) {
    const [key, value] = entries[i];
    processClassesRecursively(value, getPart(classPartObject, key), classGroupId, theme);
  }
};
const getPart = (classPartObject, path) => {
  let current = classPartObject;
  const parts = path.split(CLASS_PART_SEPARATOR);
  const len = parts.length;
  for (let i = 0; i < len; i++) {
    const part = parts[i];
    let next = current.nextPart.get(part);
    if (!next) {
      next = createClassPartObject();
      current.nextPart.set(part, next);
    }
    current = next;
  }
  return current;
};
// Type guard maintains monomorphic check
const isThemeGetter = func => 'isThemeGetter' in func && func.isThemeGetter === true;

// LRU cache implementation using plain objects for simplicity
const createLruCache = maxCacheSize => {
  if (maxCacheSize < 1) {
    return {
      get: () => undefined,
      set: () => {}
    };
  }
  let cacheSize = 0;
  let cache = Object.create(null);
  let previousCache = Object.create(null);
  const update = (key, value) => {
    cache[key] = value;
    cacheSize++;
    if (cacheSize > maxCacheSize) {
      cacheSize = 0;
      previousCache = cache;
      cache = Object.create(null);
    }
  };
  return {
    get(key) {
      let value = cache[key];
      if (value !== undefined) {
        return value;
      }
      if ((value = previousCache[key]) !== undefined) {
        update(key, value);
        return value;
      }
    },
    set(key, value) {
      if (key in cache) {
        cache[key] = value;
      } else {
        update(key, value);
      }
    }
  };
};
const IMPORTANT_MODIFIER = '!';
const MODIFIER_SEPARATOR = ':';
const EMPTY_MODIFIERS = [];
// Pre-allocated result object shape for consistency
const createResultObject = (modifiers, hasImportantModifier, baseClassName, maybePostfixModifierPosition, isExternal) => ({
  modifiers,
  hasImportantModifier,
  baseClassName,
  maybePostfixModifierPosition,
  isExternal
});
const createParseClassName = config => {
  const {
    prefix,
    experimentalParseClassName
  } = config;
  /**
   * Parse class name into parts.
   *
   * Inspired by `splitAtTopLevelOnly` used in Tailwind CSS
   * @see https://github.com/tailwindlabs/tailwindcss/blob/v3.2.2/src/util/splitAtTopLevelOnly.js
   */
  let parseClassName = className => {
    // Use simple array with push for better performance
    const modifiers = [];
    let bracketDepth = 0;
    let parenDepth = 0;
    let modifierStart = 0;
    let postfixModifierPosition;
    const len = className.length;
    for (let index = 0; index < len; index++) {
      const currentCharacter = className[index];
      if (bracketDepth === 0 && parenDepth === 0) {
        if (currentCharacter === MODIFIER_SEPARATOR) {
          modifiers.push(className.slice(modifierStart, index));
          modifierStart = index + 1;
          continue;
        }
        if (currentCharacter === '/') {
          postfixModifierPosition = index;
          continue;
        }
      }
      if (currentCharacter === '[') bracketDepth++;else if (currentCharacter === ']') bracketDepth--;else if (currentCharacter === '(') parenDepth++;else if (currentCharacter === ')') parenDepth--;
    }
    const baseClassNameWithImportantModifier = modifiers.length === 0 ? className : className.slice(modifierStart);
    // Inline important modifier check
    let baseClassName = baseClassNameWithImportantModifier;
    let hasImportantModifier = false;
    if (baseClassNameWithImportantModifier.endsWith(IMPORTANT_MODIFIER)) {
      baseClassName = baseClassNameWithImportantModifier.slice(0, -1);
      hasImportantModifier = true;
    } else if (
    /**
     * In Tailwind CSS v3 the important modifier was at the start of the base class name. This is still supported for legacy reasons.
     * @see https://github.com/dcastil/tailwind-merge/issues/513#issuecomment-2614029864
     */
    baseClassNameWithImportantModifier.startsWith(IMPORTANT_MODIFIER)) {
      baseClassName = baseClassNameWithImportantModifier.slice(1);
      hasImportantModifier = true;
    }
    const maybePostfixModifierPosition = postfixModifierPosition && postfixModifierPosition > modifierStart ? postfixModifierPosition - modifierStart : undefined;
    return createResultObject(modifiers, hasImportantModifier, baseClassName, maybePostfixModifierPosition);
  };
  if (prefix) {
    const fullPrefix = prefix + MODIFIER_SEPARATOR;
    const parseClassNameOriginal = parseClassName;
    parseClassName = className => className.startsWith(fullPrefix) ? parseClassNameOriginal(className.slice(fullPrefix.length)) : createResultObject(EMPTY_MODIFIERS, false, className, undefined, true);
  }
  if (experimentalParseClassName) {
    const parseClassNameOriginal = parseClassName;
    parseClassName = className => experimentalParseClassName({
      className,
      parseClassName: parseClassNameOriginal
    });
  }
  return parseClassName;
};

/**
 * Sorts modifiers according to following schema:
 * - Predefined modifiers are sorted alphabetically
 * - When an arbitrary variant appears, it must be preserved which modifiers are before and after it
 */
const createSortModifiers = config => {
  // Pre-compute weights for all known modifiers for O(1) comparison
  const modifierWeights = new Map();
  // Assign weights to sensitive modifiers (highest priority, but preserve order)
  config.orderSensitiveModifiers.forEach((mod, index) => {
    modifierWeights.set(mod, 1000000 + index); // High weights for sensitive mods
  });
  return modifiers => {
    const result = [];
    let currentSegment = [];
    // Process modifiers in one pass
    for (let i = 0; i < modifiers.length; i++) {
      const modifier = modifiers[i];
      // Check if modifier is sensitive (starts with '[' or in orderSensitiveModifiers)
      const isArbitrary = modifier[0] === '[';
      const isOrderSensitive = modifierWeights.has(modifier);
      if (isArbitrary || isOrderSensitive) {
        // Sort and flush current segment alphabetically
        if (currentSegment.length > 0) {
          currentSegment.sort();
          result.push(...currentSegment);
          currentSegment = [];
        }
        result.push(modifier);
      } else {
        // Regular modifier - add to current segment for batch sorting
        currentSegment.push(modifier);
      }
    }
    // Sort and add any remaining segment items
    if (currentSegment.length > 0) {
      currentSegment.sort();
      result.push(...currentSegment);
    }
    return result;
  };
};
const createConfigUtils = config => ({
  cache: createLruCache(config.cacheSize),
  parseClassName: createParseClassName(config),
  sortModifiers: createSortModifiers(config),
  postfixLookupClassGroupIds: createPostfixLookupClassGroupIds(config),
  ...createClassGroupUtils(config)
});
const createPostfixLookupClassGroupIds = config => {
  const lookup = Object.create(null);
  const classGroupIds = config.postfixLookupClassGroups;
  if (classGroupIds) {
    for (let i = 0; i < classGroupIds.length; i++) {
      lookup[classGroupIds[i]] = true;
    }
  }
  return lookup;
};
const SPLIT_CLASSES_REGEX = /\s+/;
const mergeClassList = (classList, configUtils) => {
  const {
    parseClassName,
    getClassGroupId,
    getConflictingClassGroupIds,
    sortModifiers,
    postfixLookupClassGroupIds
  } = configUtils;
  /**
   * Set of classGroupIds in following format:
   * `{importantModifier}{variantModifiers}{classGroupId}`
   * @example 'float'
   * @example 'hover:focus:bg-color'
   * @example 'md:!pr'
   */
  const classGroupsInConflict = [];
  const classNames = classList.trim().split(SPLIT_CLASSES_REGEX);
  let result = '';
  for (let index = classNames.length - 1; index >= 0; index -= 1) {
    const originalClassName = classNames[index];
    const {
      isExternal,
      modifiers,
      hasImportantModifier,
      baseClassName,
      maybePostfixModifierPosition
    } = parseClassName(originalClassName);
    if (isExternal) {
      result = originalClassName + (result.length > 0 ? ' ' + result : result);
      continue;
    }
    let hasPostfixModifier = !!maybePostfixModifierPosition;
    let classGroupId;
    if (hasPostfixModifier) {
      const baseClassNameWithoutPostfix = baseClassName.substring(0, maybePostfixModifierPosition);
      classGroupId = getClassGroupId(baseClassNameWithoutPostfix);
      const classGroupIdWithPostfix = classGroupId && postfixLookupClassGroupIds[classGroupId] ? getClassGroupId(baseClassName) : undefined;
      if (classGroupIdWithPostfix && classGroupIdWithPostfix !== classGroupId) {
        classGroupId = classGroupIdWithPostfix;
        hasPostfixModifier = false;
      }
    } else {
      classGroupId = getClassGroupId(baseClassName);
    }
    if (!classGroupId) {
      if (!hasPostfixModifier) {
        // Not a Tailwind class
        result = originalClassName + (result.length > 0 ? ' ' + result : result);
        continue;
      }
      classGroupId = getClassGroupId(baseClassName);
      if (!classGroupId) {
        // Not a Tailwind class
        result = originalClassName + (result.length > 0 ? ' ' + result : result);
        continue;
      }
      hasPostfixModifier = false;
    }
    // Fast path: skip sorting for empty or single modifier
    const variantModifier = modifiers.length === 0 ? '' : modifiers.length === 1 ? modifiers[0] : sortModifiers(modifiers).join(':');
    const modifierId = hasImportantModifier ? variantModifier + IMPORTANT_MODIFIER : variantModifier;
    const classId = modifierId + classGroupId;
    if (classGroupsInConflict.indexOf(classId) > -1) {
      // Tailwind class omitted due to conflict
      continue;
    }
    classGroupsInConflict.push(classId);
    const conflictGroups = getConflictingClassGroupIds(classGroupId, hasPostfixModifier);
    for (let i = 0; i < conflictGroups.length; ++i) {
      const group = conflictGroups[i];
      classGroupsInConflict.push(modifierId + group);
    }
    // Tailwind class not in conflict
    result = originalClassName + (result.length > 0 ? ' ' + result : result);
  }
  return result;
};

/**
 * Observes every successful class-map lookup needed to merge a single candidate. Build-time pruning needs intermediate base matches as well as a final slash match, or removing a base matcher can change runtime precedence.
 * Reuse the merge engine rather than reproducing its decisions. Instrumentation stays in this tooling-only entry point and adds no work to normal merging.
 */
const createClassGroupLookup = config => {
  const configUtils = createConfigUtils(config);
  return className => {
    const matches = [];
    mergeClassList(className, {
      ...configUtils,
      getClassGroupId(lookupName) {
        const classGroupId = configUtils.getClassGroupId(lookupName);
        if (classGroupId) {
          matches.push({
            className: lookupName,
            classGroupId
          });
        }
        return classGroupId;
      }
    });
    return matches;
  };
};
export { createClassGroupLookup, createClassGroupUtils, createParseClassName };
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