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#include "zero-pinyin-service.h"
#include "parse-pinyin.h"
void
get_candidates_test (const char* preedit_str,
const guint fetch_size,
GVariantBuilder *candidates_builder,
GVariantBuilder *matched_lengths_builder)
{
if (g_str_equal (preedit_str, "liyifeng")) {
const gchar *matches[] = {"李易峰", "利益", "礼仪", "离异", "里", "理", "力"};
guint matched_lengths[] = {8, 4, 4, 4, 2, 2, 2};
for (guint i = 0; i < G_N_ELEMENTS (matches); ++i) {
g_variant_builder_add (candidates_builder, "s", matches[i]);
g_variant_builder_add (matched_lengths_builder, "u", matched_lengths[i]);
}
} else if (g_str_equal (preedit_str, "feng")) {
const gchar *matches[] = {"风", "封", "疯", "丰", "凤"};
guint matched_lengths[] = {4, 4, 4, 4, 4, 4};
for (guint i = 0; i < G_N_ELEMENTS (matches); ++i) {
g_variant_builder_add (candidates_builder, "s", matches[i]);
g_variant_builder_add (matched_lengths_builder, "u", matched_lengths[i]);
}
} else if (g_str_equal (preedit_str, "yifeng")) {
const gchar *matches[] = {"一封", "遗风", "艺", "依", "一", "以"};
guint matched_lengths[] = {6, 6, 2, 2, 2, 2};
for (guint i = 0; i < G_N_ELEMENTS (matches); ++i) {
g_variant_builder_add (candidates_builder, "s", matches[i]);
g_variant_builder_add (matched_lengths_builder, "u", matched_lengths[i]);
}
}
}
/**
* build where clause for build_sql_for_n_pinyin().
*
* @pylist: the pinyin list.
* @n: number of Pinyin to use in pylist.
*
* returns: where_clause, caller should g_free() result after use.
*/
static char*
build_where_clause (GList* pylist,
const guint n)
{
GString* s = NULL;
GList* iter = pylist;
gboolean first_condition_done = FALSE;
Pinyin* thispy = NULL;
s = g_string_new ("");
for (guint i = 0; i < n; ++i) {
g_assert_nonnull (iter);
thispy = (Pinyin*) iter->data;
if (thispy->shengmu_i) {
if (G_LIKELY (first_condition_done)) {
g_string_append_printf (s, "AND s%u=%d ", i, thispy->shengmu_i);
} else {
g_string_append_printf (s, "s%u=%d ", i, thispy->shengmu_i);
first_condition_done = TRUE;
}
}
if (thispy->yunmu_i) {
if (G_LIKELY (first_condition_done)) {
g_string_append_printf (s, "AND y%u=%d ", i, thispy->yunmu_i);
} else {
g_string_append_printf (s, "y%u=%d ", i, thispy->yunmu_i);
first_condition_done = TRUE;
}
}
iter = iter->next;
}
gchar* result = s->str;
g_string_free (s, FALSE);
return result;
}
/**
* build a SQL to query candidates for first n pinyin in pylist.
* n can be from 1 to len(pylist).
*
* caller should free result with g_free() after use.
*/
static char*
build_sql_for_n_pinyin (GList* pylist,
const guint n,
const guint limit)
{
/* always keep one space after current term */
GString* sql = NULL;
gchar* where_clause = NULL;
sql = g_string_new ("SELECT MAX(user_freq), phrase, MAX(freq) FROM (");
g_string_append_printf (
sql, "SELECT 0 AS user_freq, phrase, freq FROM "
"maindb.py_phrase_%u WHERE ", n - 1);
where_clause = build_where_clause (pylist, n);
g_assert_nonnull (where_clause);
g_message ("where_clause=%s", where_clause);
sql = g_string_append (sql, where_clause);
sql = g_string_append (sql, "UNION ");
g_string_append_printf (
sql, "SELECT user_freq, phrase, freq FROM "
"userdb.py_phrase_%u WHERE ", n - 1);
sql = g_string_append (sql, where_clause);
sql = g_string_append (
sql, ") "
"WHERE phrase NOT IN (SELECT phrase FROM userdb.not_phrase) "
"GROUP BY phrase ORDER BY user_freq DESC, freq DESC ");
g_string_append_printf (sql, "LIMIT %u;", limit);
char* result = sql->str;
g_free (where_clause);
g_string_free (sql, FALSE);
return result;
}
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/**
* For a candidate of length group_size, calculate the matched py length.
*
* This is part of get_candidates_for_n_pinyin().
*
* see param meaning there.
*/
static guint
get_matched_py_length (const char* preedit_str,
GList* pylist,
const guint group_size)
{
guint matched_py_length = 0;
GList* iter = pylist;
g_assert_cmpint (group_size, >=, 1);
/* For usual pinyin string, just add up the Pinyin length. But for
* pinyin that contains ', when a Pinyin in pylist is used, also take
* the ' before and after it. */
for (guint i = 0; i < group_size; ++i) {
while (preedit_str[matched_py_length] == '\'') {
matched_py_length++;
}
matched_py_length += ((Pinyin*) iter->data)->length;
while (preedit_str[matched_py_length] == '\'') {
matched_py_length++;
}
iter = iter->next;
}
return matched_py_length;
}
/**
* fetch candidates for a fixed word length.
*
* @db: sqlite3 db handler.
* @preedit_str: the pinyin preedit str. can contain '. This is needed to
* calculate matched_py_length.
* @pylist: the pinyin list.
* @group_size: the fixed word length. use this many pinyin from pinyin list.
* @limit: fetch this many result is enough for user. more is not a problem though.
* @candidates: the result candidate list. caller should free this after use.
*
* returns: how many candidates fetched.
*/
static guint
get_candidates_for_n_pinyin (sqlite3* db,
GList* pylist,
const guint group_size,
const guint limit,
GList** candidates)
{
const guint DEFAULT_LIMIT = 50;
GList* result = NULL; /* GList of Candidate */
g_assert_nonnull (db);
g_assert_cmpint (group_size, >=, 1);
g_assert_cmpint (group_size, <=, g_list_length (pylist));
gint candidates_count = 0;
gint r = 0;
/* build SQL and run SQL query */
char* sql = NULL;
sql = build_sql_for_n_pinyin (pylist, group_size, MAX (limit, DEFAULT_LIMIT));
g_message ("build_sql_for_n_pinyin result SQL:\n\n%s\n", sql);
guint matched_py_length = get_matched_py_length (preedit_str, pylist, group_size);
sqlite3_stmt* stmt = NULL;
const char* unused;
Candidate* c = NULL;
r = sqlite3_prepare_v2 (db, sql, -1, &stmt, &unused);
g_assert_nonnull (unused);
g_assert_cmpstr (unused, ==, "");
if (strlen (unused)) {
g_warning ("part of sql is unused \"%s\" length=%zu",
unused, strlen (unused));
}
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while (TRUE) {
r = sqlite3_step (stmt);
if (r == SQLITE_DONE) {
break;
} else if (r == SQLITE_ROW) {
c = g_new (Candidate, 1);
/* sql SELECT should select these 3 columns in order */
c->user_freq = sqlite3_column_int (stmt, 0);
c->str = g_strdup ((const char*) sqlite3_column_text (stmt, 1));
c->freq = sqlite3_column_int (stmt, 2);
c->matched_py_length = matched_py_length;
if (g_utf8_validate (c->str, -1, NULL)) {
result = g_list_prepend (result, c);
candidates_count++;
} else {
g_warning ("ignore non utf8 phrase: %s", c->str);
}
} else if (r == SQLITE_BUSY) {
g_warning ("sqlite3_step got SQLITE_BUSY");
break;
} else {
g_warning ("sqlite3_step error: %d (%s)",
r, sqlite3_errmsg (db));
break;
}
}
r = sqlite3_finalize (stmt);
if (r != SQLITE_OK) {
g_debug ("sqlite3_finalize error: %d (%s)", r, sqlite3_errmsg (db));
}
/* store query result in a new GList */
*candidates = g_list_reverse (result);
return candidates_count;
}
void
get_candidates (sqlite3* db,
const char* preedit_str,
const guint fetch_size,
GVariantBuilder *candidates_builder,
GVariantBuilder *matched_lengths_builder)
{
if (! db) {
g_warning ("No db connection, can't get candidates.");
return;
}
GList* pylist = NULL;
guint pylist_len = 0;
pylist = parse_pinyin (preedit_str, 15);
pylist_len = g_list_length (pylist);
guint group_size = pylist_len;
guint fetched_size = 0;
guint r = 0;
GList* candidates = NULL;
while (fetched_size < fetch_size && group_size > 0) {
g_message ("phrase length=%u", group_size);
r = get_candidates_for_n_pinyin (db, preedit_str, pylist, group_size, fetch_size - fetched_size, &candidates);
if (candidates) {
GList* iter = g_list_first (candidates);
Candidate* c = NULL;
while (iter != NULL) {
c = (Candidate*) iter->data;
g_variant_builder_add (candidates_builder, "s",
c->str);
g_free (c->str);
g_variant_builder_add (matched_lengths_builder, "u",
c->matched_py_length);
iter = iter->next;
}
g_list_free_full (candidates, g_free);
}
g_message ("%u candidates found", r);
fetched_size += r;
group_size--;
}
g_message ("returning %u candidates", fetched_size);
g_list_free_full (pylist, g_free);
}