#include "term.h"

#define CHR         sizeof(char)
#define NLEN(str)   (str) == NULL ? 0 : strlen((str))

static regex_t ptn;
static bool ptn_init = false;


/**
 * Free global regex struct. Register with atexit().
 */
void term_cleanup() { if (ptn_init) regfree(&ptn); }


int
LSUP_term_init(
        LSUP_Term *term, LSUP_term_type type,
        const char *data, char *datatype, char *lang)
{
    term->type = type;
    if (data == NULL) return -1;

    if (term->type == LSUP_TERM_URI) {
        if (UNLIKELY(!ptn_init)) {
            assert (regcomp(&ptn, URI_REGEX_STR, REG_EXTENDED) == 0);
            ptn_init = true;
            atexit(term_cleanup);
        }

        if (regexec(&ptn, data, 0, NULL, 0) != 0) {
            printf("Error matching URI pattern.\n");

            return -1;
        }
    }

    term->data = malloc(strlen(data) + 1);
    strcpy(term->data, data);

    if (datatype != NULL) {
        term->datatype = malloc(strlen(datatype) + 1);
        strcpy(term->datatype, datatype);
    } else {
        term->datatype = NULL;
    }
    if (lang != NULL) {
        // TODO validate language and country code
        //char lsize = 5 ? lang[2] == "-" : 2;
        memcpy(term->lang, lang, LANG_SIZE);
    } else {
        memset(term->lang, 0, LANG_SIZE);
    }

    return 0;
}


LSUP_Term
*LSUP_term_new(
        LSUP_term_type type, const char *data, char *datatype, char *lang) {

    LSUP_Term *term;

    CRITICAL(term = malloc(sizeof(LSUP_Term)));
    LSUP_term_init(term, type, data, datatype, lang);

    return term;
}


char *
LSUP_term_gen_random_str()
{
    uuid_t uuid;
    uuid_generate_random(uuid);

    uuid_str_t uuid_str;
    uuid_unparse_lower(uuid, uuid_str);

    static char uri[UUIDSTR_SIZE + 10];
    sprintf(uri, "urn:uuid4:%s", uuid_str);

    return uri;
}


LSUP_rc
LSUP_term_serialize(const LSUP_Term *term, LSUP_Buffer *sterm)
{
    size_t size, data_len, datatype_len,
           data_idx, datatype_idx, lang_idx;

    if (UNLIKELY(term == NULL)) return LSUP_NOACTION;

    data_idx = CHR;
    data_len = strlen(term->data) + CHR;

    size = data_idx + data_len;

    if (term->datatype != NULL) {
        datatype_idx = size;
        datatype_len = strlen(term->datatype) + CHR;
        size += datatype_len;

        if (strlen(term->lang) > 0) {
            lang_idx = size;
            size += LANG_SIZE;
        }
    }

    //TRACE("Serialized term size: %lu", size);
    LSUP_buffer_init(sterm, size);

    // Copy type.
    memset(sterm->addr, (unsigned char)term->type, CHR);
    // Copy data.
    memcpy(sterm->addr + data_idx, term->data, data_len);

    if (term->datatype != NULL) {
        // Copy data type.
        memcpy(sterm->addr + datatype_idx, term->datatype, datatype_len);

        if (strlen(term->lang) > 0) {
            // Copy lang tag.
            memcpy(sterm->addr + lang_idx, term->lang, LANG_SIZE);
        }
    }

    return 0;
}


int
LSUP_term_deserialize(const LSUP_Buffer *sterm, LSUP_Term *term)
{
    size_t cur;
    char *data, *datatype = NULL;
    langtag lang = "\00";

    char type = ((char*)(sterm->addr))[0];

    cur = CHR;
    data = (char*)sterm->addr + cur;
    cur += strlen(data) + CHR;

    if (type == LSUP_TERM_LITERAL) {
        datatype = (char*)sterm->addr + cur;
        cur += strlen(datatype) + CHR;
        if (strlen(datatype) == 0)
            datatype = NULL;

        if (cur < sterm->size)
            strcpy(lang, sterm->addr + cur);
    }

    LSUP_term_init(term, type, data, datatype, lang);

    return 0;
}


bool LSUP_term_equals(const LSUP_Term *term1, const LSUP_Term *term2)
{
    if (term1->type != term2->type)
        return false;

    if (strcmp(term1->data, term2->data) != 0)
        return false;

    if (term1->type == LSUP_TERM_LITERAL) {
        if ((term1->datatype == NULL) != (term2->datatype == NULL)) // XOR
            return false;

        if (
                term1->datatype != NULL &&
                strcmp(term1->datatype, term2->datatype) != 0)
            return false;

        if ((term1->lang == NULL) != (term2->lang == NULL)) // XOR
            return false;

        if (
                term1->lang != NULL &&
                strcmp(term1->lang, term2->lang) != 0)
            return false;
    }

    return true;
}


void LSUP_term_done(LSUP_Term *term)
{
    if (LIKELY(term->data != NULL)) {
        free(term->data);
        term->data = NULL;
    }

    if (term->datatype != NULL) {
        free(term->datatype);
        term->datatype = NULL;
    }
}


void LSUP_term_free(LSUP_Term *term)
{
    if (LIKELY(term != NULL)) {
        LSUP_term_done(term);
        free(term);
        term = NULL;
    }
}


// Extern inline functions.

LSUP_Key LSUP_sterm_to_key(const LSUP_SerTerm *sterm);

LSUP_Key LSUP_term_to_key(const LSUP_Term *term);