X-Git-Url: http://git.indexdata.com/?p=yaz-moved-to-github.git;a=blobdiff_plain;f=src%2Fstemmer.c;h=5829d9f5dd396abee8b39ccbe47e46b8fc0f02fb;hp=b544ebc2cf023abcb3a8b0386d5c966ab493347c;hb=5a3e6fa63181ab4afa8bce5f01c6de016a333334;hpb=9e04bbdbec82ea6f5795dc2d16bd9876ecc7762f

diff --git a/src/stemmer.c b/src/stemmer.c
index b544ebc..5829d9f 100644
--- a/src/stemmer.c
+++ b/src/stemmer.c
@@ -10,32 +10,106 @@
 
 #include <yaz/stemmer.h>
 
+#include <yaz/xmalloc.h>
+
+#include <libstemmer.h>
+
 #include <unicode/ustring.h>  /* some more string fcns*/
 #include <unicode/uchar.h>    /* char names           */
 
+enum stemmer_implementation {
+    yaz_no_operation,
+    yaz_snowball
+};
 struct yaz_stemmer_t
 {
     int implementation;
+    // Required for cloning.
+    char *locale;
+    char *rule;
     union {
-        struct sb_stemmer *snowballer;
+        struct sb_stemmer *sb_stemmer;
     };
 };
 
-yaz_stemmer_p yaz_stemmer_create(const char *locale, const char *rule, UErrorCode *status) {
-    return 0;
+const char* yaz_stemmer_lookup_charenc(const char *charenc, const char *rule) {
+    return "UTF_8";
 }
 
-yaz_stemmer_p yaz_stemmer_clone(yaz_stemmer_p stemmer) {
-    return 0;
+const char* yaz_stemmer_lookup_algorithm(const char *locale, const char *rule) {
+    return locale;
 }
 
-void yaz_stemmer_stem(yaz_stemmer_p stemmer, struct icu_buf_utf16 *dst, struct icu_buf_utf16* src, UErrorCode *status) {
+yaz_stemmer_p yaz_stemmer_snowball_create(const char *locale, const char *rule, UErrorCode *status) {
+    const char *charenc = yaz_stemmer_lookup_charenc(locale, rule);
+    const char *algorithm = yaz_stemmer_lookup_algorithm(locale,rule);
+    struct sb_stemmer *stemmer = sb_stemmer_new(algorithm, charenc);
+    yaz_stemmer_p yaz_stemmer;
+    yaz_log(YLOG_DEBUG, "create snowball stemmer: algoritm %s charenc %s ", algorithm, charenc);
+    if (stemmer == 0) {
+        *status = U_ARGUMENT_TYPE_MISMATCH;
+        yaz_log(YLOG_DEBUG, "failed to create stemmer. Creating NOP stemmer");
 
+        return 0;
+    }
+    yaz_stemmer = xmalloc(sizeof(*yaz_stemmer));
+    yaz_stemmer->implementation = yaz_snowball;
+    yaz_stemmer->locale = xstrdup(locale);
+    yaz_stemmer->rule = xstrdup(rule);
+    yaz_stemmer->sb_stemmer = stemmer;
+    yaz_log(YLOG_DEBUG, "created snowball stemmer: algoritm %s charenc %s ", algorithm, charenc);
+    return yaz_stemmer;
 }
 
-void yaz_stemmer_destroy(yaz_stemmer_p stemmer) {
+yaz_stemmer_p yaz_stemmer_create(const char *locale, const char *rule, UErrorCode *status) {
+    *status = U_ZERO_ERROR;
+    // dispatch logic required if more algorithms is implemented.
+    yaz_log(YLOG_DEBUG, "create stemmer: locale %s rule %s ", locale, rule);
+    return yaz_stemmer_snowball_create(locale, rule, status);
+}
 
+yaz_stemmer_p yaz_stemmer_clone(yaz_stemmer_p stemmer) {
+    UErrorCode error = U_ZERO_ERROR;
+    return yaz_stemmer_create(stemmer->locale, stemmer->rule, &error);
+}
 
+void yaz_stemmer_stem(yaz_stemmer_p stemmer, struct icu_buf_utf16 *dst, struct icu_buf_utf16* src, UErrorCode *status)
+{
+    switch(stemmer->implementation) {
+        case yaz_snowball: {
+            struct icu_buf_utf8 *utf8_buf = icu_buf_utf8_create(0);
+            icu_utf16_to_utf8(utf8_buf, src, status);
+            if (*status == U_ZERO_ERROR) {
+                const sb_symbol *cstr = (const sb_symbol*) icu_buf_utf8_to_cstr(utf8_buf);
+                const sb_symbol *sb_symbol = sb_stemmer_stem(stemmer->sb_stemmer, cstr, utf8_buf->utf8_len);
+                if (sb_symbol == 0) {
+                    icu_buf_utf16_copy(dst, src);
+                }
+                else {
+                    const char *cstr = (const char *) sb_symbol;
+                    icu_utf16_from_utf8_cstr(dst, cstr , status);
+                }
+            }
+            icu_buf_utf16_destroy(utf8_buf);
+            return ;
+            break;
+        }
+        default: {
+            // Default return the same as given.
+            icu_buf_utf16_copy(dst, src);
+        }
+    }
+}
+
+void yaz_stemmer_destroy(yaz_stemmer_p stemmer) {
+    switch (stemmer->implementation) {
+    case yaz_snowball:
+        sb_stemmer_delete(stemmer->sb_stemmer);
+        break;
+    }
+    xfree(stemmer->locale);
+    xfree(stemmer->rule);
+    xfree(stemmer);
 }
 
 #endif /* YAZ_HAVE_ICU */