SelectorSequence.c

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/*
 * ObjectivelyMVC: Object oriented MVC framework for OpenGL, SDL2 and GNU 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 <string.h>
 
#include <Objectively/MutableArray.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);
 
    MutableArray *selectorSequences = $$(MutableArray, 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