compatible with maximum forward parser

1 files changed, 46 insertions, 0 deletions

diff --git a/src/storage/pinyin_parser2.cpp b/src/storage/pinyin_parser2.cpp
index 727dc28..2e2b649 100644
--- a/src/storage/pinyin_parser2.cpp
+++ b/src/storage/pinyin_parser2.cpp
@@ -283,6 +283,49 @@ int FullPinyinParser2::parse (pinyin_option_t options, ChewingKeyVector & keys,
             next_sep = k;
         }
 
+        /* Heuristic Method:
+         *   do maximum forward match first. */
+        for (size_t pos = i; pos < next_sep; ++pos) {
+            curstep = &g_array_index(m_parse_steps, parse_value_t, pos);
+            size_t try_len = std_lite::min
+                (pos + max_full_pinyin_length, next_sep);
+            for (size_t n = try_len; n > pos; --n) {
+                nextstep = &g_array_index(m_parse_steps, parse_value_t, n);
+
+                /* gen next step */
+                const char * onepinyin = input + pos;
+                gint16 onepinyinlen = n - pos;
+                value = parse_value_t();
+
+                ChewingKey key; ChewingKeyRest rest;
+                bool parsed = parse_one_key
+                    (options, key, rest, onepinyin, onepinyinlen);
+                rest.m_raw_begin = pos; rest.m_raw_end = n;
+
+                if (!parsed)
+                    continue;
+
+                //printf("onepinyin:%s len:%d\n", onepinyin, onepinyinlen);
+                value.m_key = key; value.m_key_rest = rest;
+                value.m_num_keys = curstep->m_num_keys + 1;
+                value.m_parsed_len = curstep->m_parsed_len + onepinyinlen;
+                value.m_last_step = pos;
+
+                /* save next step */
+                if (-1 == nextstep->m_last_step)
+                    *nextstep = value;
+                if (value.m_parsed_len > nextstep->m_parsed_len)
+                    *nextstep = value;
+                if (value.m_parsed_len == nextstep->m_parsed_len &&
+                    value.m_num_keys < nextstep->m_num_keys)
+                    *nextstep = value;
+
+                /* maximum forward, set pos to n in next iteration. */
+                pos = n - 1;
+                break;
+            }
+        }
+
         /* dynamic programming here. */
         for (size_t m = i; m < next_sep; ++m) {
             curstep = &g_array_index(m_parse_steps, parse_value_t, m);
@@ -302,6 +345,9 @@ int FullPinyinParser2::parse (pinyin_option_t options, ChewingKeyVector & keys,
                 rest.m_raw_begin = m; rest.m_raw_end = n;
                 if (!parsed)
                     continue;
+
+                //printf("onepinyin:%s len:%d\n", onepinyin, onepinyinlen);
+
                 value.m_key = key; value.m_key_rest = rest;
                 value.m_num_keys = curstep->m_num_keys + 1;
                 value.m_parsed_len = curstep->m_parsed_len + onepinyinlen;