Implement Standard Slack Emoji completion using /input command_* hooks

See commit 5217251e94 for details

README.org

@@ -35,7 +35,7 @@
 
   - libwebsockets (static, submodule)
   - json-c (static, submodule)
-  - weechat (>= v1.4)
+  - weechat (>= v1.7)
 
 * Building
 
@@ -84,6 +84,11 @@
 ** TODO [#B] Implement websocket ping and pong (milestone v0.4)
   - [ ] Add ping timer and pong handler (see [[http://github.com/bqv/weechat-slack/issues/9][#9]])
 ** TODO [#C] Implement remaining api endpoints and events (milestone v0.5)
+  - [ ] Support all channel types
+    - [X] +Channels+
+    - [ ] Groups
+    - [ ] MPIMs
+    - [ ] IMs
   - [ ] Complete api endpoint set
   - [ ] Complete api event set
 ** TODO [#C] Implement full weechat functionality (milestone v0.6)

debian/control

@@ -16,7 +16,7 @@ Vcs-Browser: https://github.com/bqv/weechat-slack
 Package: weechat-slack
 Architecture: any
 Depends:
-    weechat (>= 1.4),
+    weechat (>= 1.7),
     ${shlibs:Depends},
     ${misc:Depends}
 Description: Fast, light and extensible chat client - Slack plugin

slack-completion.c

@@ -13,6 +13,14 @@
 
 void slack_completion_init()
 {
+    weechat_hook_command_run("/input return",
+                             &slack_emoji_input_replace_cb,
+                             NULL, NULL);
+    
+    weechat_hook_command_run("/input complete*",
+                             &slack_emoji_input_complete_cb,
+                             NULL, NULL);
+    
     weechat_hook_completion("slack_emoji",
                             N_("slack emoji"),
                             &slack_emoji_complete_by_name_cb,

slack-emoji.c

@@ -4,6 +4,7 @@
 
 #include <stdlib.h>
 #include <string.h>
+#include <stdio.h>
 
 #include "weechat-plugin.h"
 #include "slack.h"
@@ -12,6 +13,7 @@
 #include "slack-emoji.inc"
 
 #define MIN(a,b) (((a)<(b))?(a):(b))
+#define MAX(a,b) (((a)>(b))?(a):(b))
 
 static int emoji_byname_cmp(const void *p1, const void *p2)
 {
@@ -25,28 +27,7 @@ static int emoji_bytext_cmp(const void *p1, const void *p2)
                       ((struct t_slack_emoji_by_text *)p2)->text);
 }
 
-static size_t levenshtein_dist(const char *s, size_t len_s, const char *t, size_t len_t)
+static size_t modified_wagner_fischer(const char *src, const char *targ)
-{ 
-    size_t cost;
-
-    /* base case: empty strings */
-    if (len_s == 0) return len_t;
-    if (len_t == 0) return len_s;
-
-    /* test if last characters of the strings match */
-    if (s[len_s-1] == t[len_t-1])
-        cost = 0;
-    else
-        cost = 1;
-
-    /* delete char from s, delete char from t, and delete char from both */
-    size_t delete  = levenshtein_dist(s, len_s - 1, t, len_t    ) + 1;
-    size_t insert  = levenshtein_dist(s, len_s    , t, len_t - 1) + 1;
-    size_t replace = levenshtein_dist(s, len_s - 1, t, len_t - 1) + cost;
-    return MIN( MIN( delete, insert ), replace );
-}
-
-static size_t wagner_fischer(const char *src, const char *targ)
 {
     size_t len = strlen(targ) + 1;
     size_t above[len], below[len];
@@ -60,7 +41,8 @@ static size_t wagner_fischer(const char *src, const char *targ)
         for (size_t *d = above, *a = above + 1, *l = below, *c = below + 1;
              c < below + len; ++d, ++a, ++l, ++c)
         {
-			*c = MIN( *src_at == *targ_at ? *d : *d + 1, MIN( *a + 1, *l + 1 ) );
+            /*        |-------------replace-----------|       |isrt|  |delt|   */
+            *c = MIN( *src_at == *targ_at ? *d : *d + 1, MIN( *a + 0, *l + 1 ) );
             ++targ_at;
         }
         for (size_t *a = above, *b = below; a < above + len; ++a, ++b) *a = *b;
@@ -70,19 +52,96 @@ static size_t wagner_fischer(const char *src, const char *targ)
     return above[len-1];
 }
 
+static size_t longest_common_substring(const char *X, const char *Y)
+{
+    const size_t n = strlen(X);
+    const size_t m = strlen(Y);
+    size_t i, j, result = 0;
+    size_t **L;
+
+    L = malloc(sizeof(size_t *) * (n + 1));
+    L[0] = malloc(sizeof(size_t) * (m + 1) * (n + 1));
+    
+    for (i = 0; i <= n; i++)
+        L[i] = (*L + (m + 1) * i);
+  
+    /* Following steps build L[n+1][m+1] in bottom up fashion. Note 
+       that L[i][j] contains length of LCS of X[0..i-1] and Y[0..j-1] */
+    for (i = 0; i <= n; i++)
+    {
+        for (j = 0; j <= m; j++)
+        {
+            if (i == 0 || j == 0)
+            {
+                L[i][j] = 0;
+            }
+            else if (X[i-1] == Y[j-1])
+            {
+                L[i][j] = L[i - 1][j - 1] + 1;
+                if (result < L[i][j])
+                    result = L[i][j];
+            }
+            else
+            {
+                L[i][j] = 0;
+            }
+        }
+    }
+    
+    /* result now contains length of LCS for X[0..n-1] and Y[0..m-1] */
+    free(L[0]);
+    free(L);
+    return result;
+}
+
 int slack_emoji_complete_by_name_cb(const void *pointer, void *data,
                                     const char *completion_item,
                                     struct t_gui_buffer *buffer,
                                     struct t_gui_completion *completion)
+{
+    (void) pointer;
+    (void) data;
+    (void) completion_item;
+    (void) buffer;
+
+    size_t i, emoji_count = sizeof(slack_emoji_by_name)
+        / sizeof(struct t_slack_emoji_by_name);
+    
+    for (i = 0; i < emoji_count; i++)
+        weechat_hook_completion_list_add(completion,
+                                         slack_emoji_by_name[i].name,
+                                         0, WEECHAT_LIST_POS_END);
+
+    return WEECHAT_RC_OK;
+}
+
+int slack_emoji_input_complete_cb(const void *pointer, void *data,
+                                  struct t_gui_buffer *buffer,
+                                  const char *command)
 {
     struct t_slack_emoji_by_name *closest_emoji;
+    int input_pos, input_length, start, end;
+    char *new_string, *word, *new_pos;
+    const char *input_string;
 
     (void) pointer;
     (void) data;
+    (void) command;
 
-    weechat_printf(NULL, "Completing!");
+    input_string = weechat_buffer_get_string(buffer, "input");
+    input_length = strlen(input_string);
+    input_pos = weechat_buffer_get_integer(buffer, "input_pos");
+    for (start = input_pos; start > 0 && input_string[start] != ':'; start--)
+        if (input_string[start] == ' ') { break; }
+    for (end = input_pos; end < input_length && input_string[end] != ' '; end++)
+        if (input_string[end] == ':') { end++; break; }
 
-    size_t i, emoji_count = sizeof(slack_emoji_by_name)
+    if (input_string[start] != ':')
+        return WEECHAT_RC_OK;
+    else
+        word = strndup(&input_string[start], end - start);
+    
+    size_t emoji_count = sizeof(slack_emoji_by_name)
         / sizeof(struct t_slack_emoji_by_name);
     closest_emoji = malloc(sizeof(slack_emoji_by_name));
     memcpy(closest_emoji, slack_emoji_by_name,
@@ -90,20 +149,58 @@ int slack_emoji_complete_by_name_cb(const void *pointer, void *data,
 
     int edit_dist_cmp(const void *p1, const void *p2)
     {
-        return 0;
+        const struct t_slack_emoji_by_name *e1 = p1;
+        const struct t_slack_emoji_by_name *e2 = p2;
+        size_t d1 = modified_wagner_fischer(e1->name, word);
+        size_t d2 = modified_wagner_fischer(e2->name, word);
+        if (d1 == d2)
+        {
+            size_t l1 = longest_common_substring(e1->name, word);
+            size_t l2 = longest_common_substring(e2->name, word);
+            return (l1 < l2) - (l1 > l2);
+        }
+        return (d1 > d2) - (d1 < d2);
     };
     qsort(closest_emoji, emoji_count,
           sizeof(struct t_slack_emoji_by_name),
           edit_dist_cmp);
 
-    for (i = 0; i < emoji_count; i++)
+    size_t new_length = snprintf(NULL, 0, "%.*s%s%s",
-    {
+                                 start, input_string,
-        weechat_printf(NULL, closest_emoji[i].name);
+                                 closest_emoji[0].name,
-        weechat_hook_completion_list_add(completion, closest_emoji[i].name,
+                                 &input_string[end]) + 1;
-                                         0, WEECHAT_LIST_POS_END);
+    new_string = malloc(new_length);
+    snprintf(new_string, new_length, "%.*s%s%s",
+             start, input_string,
+             closest_emoji[0].name,
+             &input_string[end]);
+    weechat_buffer_set(buffer, "input", new_string);
+    
+    size_t new_pos_len = snprintf(NULL, 0, "%lu",
+                                  (unsigned long)(start +
+                                      strlen(closest_emoji[0].name) - 1));
+    new_pos = malloc(new_pos_len);
+    snprintf(new_pos, new_pos_len, "%lu",
+             (unsigned long)(start +
+                 strlen(closest_emoji[0].name) - 1));
+    weechat_buffer_set(buffer, "input_pos", new_pos);
+    
+    free(new_pos);
+    free(new_string);
+    free(closest_emoji);
+    free(word);
+    return WEECHAT_RC_OK_EAT;
 }
 
-    free(closest_emoji);
+int slack_emoji_input_replace_cb(const void *pointer, void *data,
+                                 struct t_gui_buffer *buffer,
+                                 const char *command)
+{
+    (void) pointer;
+    (void) data;
+    (void) buffer;
+    (void) command;
+    
     return WEECHAT_RC_OK;
 }
 

slack-emoji.h

@@ -10,6 +10,14 @@ int slack_emoji_complete_by_name_cb(const void *pointer, void *data,
                                     struct t_gui_buffer *buffer,
                                     struct t_gui_completion *completion);
 
+int slack_emoji_input_complete_cb(const void *pointer, void *data,
+                                  struct t_gui_buffer *buffer,
+                                  const char *command);
+
+int slack_emoji_input_replace_cb(const void *pointer, void *data,
+                                 struct t_gui_buffer *buffer,
+                                 const char *command);
+
 const char *slack_emoji_get_unicode_by_name(const char *name);
 
 const char *slack_emoji_get_unicode_by_text(const char *text);