#ifndef HTML_PARSER_H
#define HTML_PARSER_H

/*
    A small html parser with no dependencies and doesn't dynamically allocate any memory
    and can parse and repair broken html (just like web browsers)
*/

#include <stddef.h>

#ifdef __cplusplus
extern "C" {
#endif

typedef struct {
    const char *data;
    size_t size;
} HtmlStringView;

typedef struct HtmlParser HtmlParser;

typedef enum{
    HTML_PARSE_TAG_START,
    HTML_PARSE_TAG_END,
    HTML_PARSE_ATTRIBUTE,
    HTML_PARSE_TEXT,
    HTML_PARSE_JAVASCRIPT_CODE
} HtmlParseType;

/* Return 0 to continue */
typedef int (*HtmlParseCallback)(HtmlParser *html_parser, HtmlParseType parse_type, void *userdata);

#define UNCLOSED_TAGS_SIZE 2048

struct HtmlParser {
    const char *source;
    size_t source_len;
    size_t offset;
    HtmlParseCallback parse_callback;
    void *callback_userdata;

    /* The name of the current enclosing tag */
    HtmlStringView tag_name;
    HtmlStringView attribute_key;
    HtmlStringView attribute_value;
    HtmlStringView text;
    HtmlStringView text_stripped;

    HtmlStringView tag_before_void_tag;
    int is_tag_void;
    int inside_script_tag;

    size_t unclosed_tags_offset;
    HtmlStringView unclosed_tags[UNCLOSED_TAGS_SIZE];
};

/*
    Returns the value returned from |parse_callback|. 0 meaning success.
    Input text is expected to be in utf8 and may or may not have UTF8-BOM.
    Note: HTML_PARSE_TAG_START is guaranteed to be called for a tag before HTML_PARSE_TAG_END.
    Note: HTML_PARSE_TEXT may be called multiple times for a tag. For example if a tag has multiple text items split between child tags
        like this: <div>hello<h1>text</h1>world</div>.
        In this case, HTML_PARSE_TEXT will be called twice for the div tag. First with "hello" and then with "world".
    This function does 0 dynamic memory allocations.
*/
int html_parser_parse(const char *html_source, size_t len, HtmlParseCallback parse_callback, void *userdata);

/* Returns 1 if equals */
int html_string_view_equals_case_insensitive(HtmlStringView *self, HtmlStringView *other);

#ifdef __cplusplus
}
#endif

#endif /* HTML_PARSER_H */