builder.c

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#include <cwist/core/html/builder.h>
#include <cwist/core/sstring/sstring.h>
#include <cwist/core/mem/alloc.h>
#include <cjson/cJSON.h>
#include <stdlib.h>
#include <string.h>
#include <stdio.h>
 
cwist_html_element_t *cwist_html_element_create(const char *tag) {
    cwist_html_element_t *el = (cwist_html_element_t *)cwist_alloc(sizeof(cwist_html_element_t));
    if (!el) return NULL;
 
    el->tag = cwist_sstring_create();
    cwist_sstring_assign(el->tag, tag ? tag : "");
    el->attributes = cJSON_CreateObject();
    el->children = NULL;
    el->child_count = 0;
    el->inner_text = NULL;
 
    return el;
}
 
void cwist_html_element_destroy(cwist_html_element_t *el) {
    if (!el) return;
 
    if (el->tag) cwist_sstring_destroy(el->tag);
    if (el->attributes) cJSON_Delete(el->attributes);
 
    if (el->children) {
        for (int i = 0; i < el->child_count; i++) {
            cwist_html_element_destroy(el->children[i]);
        }
        cwist_free(el->children);
    }
 
    if (el->inner_text) cwist_sstring_destroy(el->inner_text);
 
    cwist_free(el);
}
 
void cwist_html_element_add_attr(cwist_html_element_t *el, const char *key, const char *value) {
    if (!el || !key || !value || !el->attributes) return;
 
    if (cJSON_HasObjectItem(el->attributes, key)) {
        cJSON_ReplaceItemInObject(el->attributes, key, cJSON_CreateString(value));
    } else {
        cJSON_AddStringToObject(el->attributes, key, value);
    }
}
 
void cwist_html_element_set_id(cwist_html_element_t *el, const char *id) {
    cwist_html_element_add_attr(el, "id", id);
}
 
void cwist_html_element_add_class(cwist_html_element_t *el, const char *class_name) {
    if (!el || !class_name || !el->attributes) return;
 
    cJSON *cls = cJSON_GetObjectItem(el->attributes, "class");
    if (cls && cls->valuestring && *cls->valuestring) {
        // Append to existing class
        cwist_sstring *s = cwist_sstring_create();
        cwist_sstring_assign(s, cls->valuestring);
        cwist_sstring_append(s, " ");
        cwist_sstring_append(s, class_name);
        cJSON_ReplaceItemInObject(el->attributes, "class",
                                  cJSON_CreateString(s->data ? s->data : ""));
        cwist_sstring_destroy(s);
    } else {
        cwist_html_element_add_attr(el, "class", class_name);
    }
}
 
void cwist_html_element_set_text(cwist_html_element_t *el, const char *text) {
    if (!el) return;
    const char *actual_text = text ? text : "";
    if (el->inner_text) {
        cwist_sstring_assign(el->inner_text, actual_text);
    } else {
        el->inner_text = cwist_sstring_create();
        cwist_sstring_assign(el->inner_text, actual_text);
    }
}
 
void cwist_html_element_add_child(cwist_html_element_t *el, cwist_html_element_t *child) {
    if (!el || !child) return;
 
    el->child_count++;
    cwist_html_element_t **new_children = (cwist_html_element_t **)cwist_realloc(
        el->children, sizeof(cwist_html_element_t *) * el->child_count);
    if (!new_children) {
        el->child_count--;
        return;
    }
    el->children = new_children;
    el->children[el->child_count - 1] = child;
}
 
static bool is_void_element(const char *tag) {
    static const char *const void_tags[] = {"area",  "base", "br",   "col",    "embed", "hr", "img",
                                            "input", "link", "meta", "source", "track", "wbr"};
    for (size_t i = 0; i < sizeof(void_tags) / sizeof(void_tags[0]); i++) {
        const char *a = tag, *b = void_tags[i];
        while (*a && (*a | 0x20) == *b) {
            a++;
            b++;
        }
        if (*a == '\0' && *b == '\0') return true;
    }
    return false;
}
 
static void render_element(cwist_html_element_t *el, cwist_sstring *out) {
    if (!el || !out) return;
 
    if (el->tag && el->tag->data && *el->tag->data) {
        cwist_sstring_append(out, "<");
        cwist_sstring_append(out, el->tag->data);
        cJSON *attr = NULL;
        cJSON_ArrayForEach(attr, el->attributes) {
            if (!attr || !attr->string) continue;
            if (cJSON_IsString(attr) && attr->valuestring) {
                cwist_sstring_append(out, " ");
                cwist_sstring_append(out, attr->string);
                cwist_sstring_append(out, "=\"");
                cwist_sstring_append_escaped(out, attr->valuestring);
                cwist_sstring_append(out, "\"");
            } else if (cJSON_IsTrue(attr)) {
                cwist_sstring_append(out, " ");
                cwist_sstring_append(out, attr->string);
            } else if (cJSON_IsNumber(attr)) {
                char num_buf[64];
                snprintf(num_buf, sizeof(num_buf), "%g", attr->valuedouble);
                cwist_sstring_append(out, " ");
                cwist_sstring_append(out, attr->string);
                cwist_sstring_append(out, "=\"");
                cwist_sstring_append(out, num_buf);
                cwist_sstring_append(out, "\"");
            }
        }
        cwist_sstring_append(out, ">");
 
        /* A void element cannot have content; an end tag like </br> would be
         * parsed by browsers as a second element. */
        if (is_void_element(el->tag->data)) return;
 
        if (el->inner_text && el->inner_text->data) {
            cwist_sstring_append_escaped(out, el->inner_text->data);
        }
 
        if (el->children) {
            for (int i = 0; i < el->child_count; i++) {
                render_element(el->children[i], out);
            }
        }
 
        cwist_sstring_append(out, "</");
        cwist_sstring_append(out, el->tag->data);
        cwist_sstring_append(out, ">");
    } else if (el->inner_text && el->inner_text->data) {
        // If no tag, just render the text (escaped)
        cwist_sstring_append_escaped(out, el->inner_text->data);
    }
}
 
cwist_sstring *cwist_html_render(cwist_html_element_t *el) {
    if (!el) return NULL;
    cwist_sstring *out = cwist_sstring_create();
    cwist_sstring_assign(out, "");
    render_element(el, out);
    return out;
}