SelectorSequence.c

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/*
 * ObjectivelyMVC: Object oriented MVC framework for SDL3 and C.
 * Copyright (C) 2014 Jay Dolan <jay@jaydolan.com>
 *
 * This software is provided 'as-is', without any express or implied
 * warranty. In no event will the authors be held liable for any damages
 * arising from the use of this software.
 *
 * Permission is granted to anyone to use this software for any purpose,
 * including commercial applications, and to alter it and redistribute it
 * freely, subject to the following restrictions:
 *
 * 1. The origin of this software must not be misrepresented; you must not
 * claim that you wrote the original software. If you use this software
 * in a product, an acknowledgment in the product documentation would be
 * appreciated but is not required.
 *
 * 2. Altered source versions must be plainly marked as such, and must not be
 * misrepresented as being the original software.
 *
 * 3. This notice may not be removed or altered from any source distribution.
 */
 
#include <assert.h>
#include <stdlib.h>
#include <string.h>
 
#include <Objectively/Array.h>
 
#include "SelectorSequence.h"
#include "View.h"
 
#define _Class _SelectorSequence
 
#pragma mark - Object
 
static void dealloc(Object *self) {
 
  SelectorSequence *this = (SelectorSequence *) self;
 
  free(this->sequence);
  release(this->simpleSelectors);
 
  super(Object, self, dealloc);
}
 
static String *description(const Object *self) {
 
  const SelectorSequence *this = (SelectorSequence *) self;
 
  return str(this->sequence);
}
 
#pragma mark - SelectorSequence
 
static SelectorSequence *initWithSequence(SelectorSequence *self, const char *sequence) {
 
  self = (SelectorSequence *) super(Object, self, init);
  if (self) {
 
    self->sequence = strtrim(sequence);
    assert(self->sequence);
 
    assert(strlen(self->sequence));
 
    self->simpleSelectors = $$(SimpleSelector, parse, self->sequence);
    assert(self->simpleSelectors->count);
  }
 
  return self;
}
 
static bool matchesView(const SelectorSequence *self, const View *view) {
 
  for (size_t i = 0; i < self->simpleSelectors->count; i++) {
    const SimpleSelector *simpleSelector = $(self->simpleSelectors, objectAtIndex, i);
    if ($(view, matchesSelector, simpleSelector) == false) {
      return false;
    }
  }
 
  return true;
}
 
static SequenceCombinator sequenceCombinator(const char *c) {
 
  SequenceCombinator combinator = SequenceCombinatorNone;
 
  while (isspace(*c)) {
    combinator = SequenceCombinatorDescendent;
    c++;
  }
 
  switch (*c) {
    case '>':
      return SequenceCombinatorChild;
    case '~':
      return SequenceCombinatorSibling;
    case '+':
      return SequenceCombinatorAdjacent;
    case '\0':
      return SequenceCombinatorTerminal;
    default:
      break;
  }
 
  return combinator;
}
 
static Array *parse(const char *rule) {
 
  assert(rule);
 
  Array *selectorSequences = $$(Array, arrayWithCapacity, 8);
  assert(selectorSequences);
 
  SequenceCombinator left = SequenceCombinatorNone;
 
  const char *c = rule;
  while (*c) {
    const size_t size = strcspn(c, " \n\t>+~");
    if (size) {
      char *sequence = calloc(1, size + 1);
      assert(sequence);
 
      strncpy(sequence, c, size);
 
      SelectorSequence *selectorSequence = $(alloc(SelectorSequence), initWithSequence, sequence);
      assert(selectorSequence);
 
      selectorSequence->right = sequenceCombinator(c + size);
      assert(selectorSequence->right);
 
      selectorSequence->left = left;
      left = selectorSequence->right;
 
      $(selectorSequences, addObject, selectorSequence);
 
      release(selectorSequence);
      free(sequence);
    }
 
    c += size;
    c += strspn(c, " \n\t>+~");
  }
 
  return (Array *) selectorSequences;
}
 
#pragma mark - Class lifecycle
 
static void initialize(Class *clazz) {
 
  ((ObjectInterface *) clazz->interface)->dealloc = dealloc;
  ((ObjectInterface *) clazz->interface)->description = description;
 
  ((SelectorSequenceInterface *) clazz->interface)->initWithSequence = initWithSequence;
  ((SelectorSequenceInterface *) clazz->interface)->matchesView = matchesView;
  ((SelectorSequenceInterface *) clazz->interface)->parse = parse;
}
 
Class *_SelectorSequence(void) {
  static Class *clazz;
  static Once once;
 
  do_once(&once, {
    clazz = _initialize(&(const ClassDef) {
      .name = "SelectorSequence",
      .superclass = _Object(),
      .instanceSize = sizeof(SelectorSequence),
      .interfaceOffset = offsetof(SelectorSequence, interface),
      .interfaceSize = sizeof(SelectorSequenceInterface),
      .initialize = initialize,
    });
  });
 
  return clazz;
}
 
#undef _Class