ime: add functions to enable/disable IME, simplify code that enables IME

We may want to be able to enable/disable IME run-time, even though we
have received an ‘enter’ IME event.

This enables us to do that.

Also add functions to enable/disable IME on a per-terminal instance
basis.

A terminal may have multiple seats focusing it, and enabling/disabling
IME in a terminal instance enables/disables IME on all those seats.

Finally, the code to enable IME is simplified; the *only* surface that
can ever receive ‘enter’ IME events is the main grid. All other
surfaces are sub-surfaces, without their own keyboard focus.

ime.c

@@ -20,43 +20,16 @@ enter(void *data, struct zwp_text_input_v3 *zwp_text_input_v3,
       struct wl_surface *surface)
 {
     struct seat *seat = data;
+
     LOG_DBG("enter: seat=%s", seat->name);
 
-    assert(seat->kbd_focus != NULL);
+    /* The main grid is the *only* input-receiving surface we have */
+    /* TODO: can we receive text_input::enter() _before_ keyboard_enter()? */
+    struct terminal UNUSED *term = seat->kbd_focus;
+    assert(term != NULL);
+    assert(term_surface_kind(term, surface) == TERM_SURF_GRID);
 
-    switch (term_surface_kind(seat->kbd_focus, surface)) {
+    ime_enable(seat);
-    case TERM_SURF_GRID:
-        zwp_text_input_v3_enable(seat->wl_text_input);
-        zwp_text_input_v3_set_content_type(
-            seat->wl_text_input,
-            ZWP_TEXT_INPUT_V3_CONTENT_HINT_NONE,
-            ZWP_TEXT_INPUT_V3_CONTENT_PURPOSE_TERMINAL);
-
-        /* TODO: set cursor rectangle */
-        zwp_text_input_v3_set_cursor_rectangle(seat->wl_text_input, 0, 0, 15, 15);
-        break;
-
-    case TERM_SURF_SEARCH:
-        /* TODO */
-        /* FALLTHROUGH */
-
-    case TERM_SURF_NONE:
-    case TERM_SURF_SCROLLBACK_INDICATOR:
-    case TERM_SURF_RENDER_TIMER:
-    case TERM_SURF_TITLE:
-    case TERM_SURF_BORDER_LEFT:
-    case TERM_SURF_BORDER_RIGHT:
-    case TERM_SURF_BORDER_TOP:
-    case TERM_SURF_BORDER_BOTTOM:
-    case TERM_SURF_BUTTON_MINIMIZE:
-    case TERM_SURF_BUTTON_MAXIMIZE:
-    case TERM_SURF_BUTTON_CLOSE:
-        zwp_text_input_v3_disable(seat->wl_text_input);
-        break;
-    }
-
-    zwp_text_input_v3_commit(seat->wl_text_input);
-    seat->ime.serial++;
 }
 
 static void
@@ -65,11 +38,7 @@ leave(void *data, struct zwp_text_input_v3 *zwp_text_input_v3,
 {
     struct seat *seat = data;
     LOG_DBG("leave: seat=%s", seat->name);
-    zwp_text_input_v3_disable(seat->wl_text_input);
+    ime_disable(seat);
-    zwp_text_input_v3_commit(seat->wl_text_input);
-    seat->ime.serial++;
-
-    ime_reset(seat);
 }
 
 static void
@@ -146,7 +115,7 @@ done(void *data, struct zwp_text_input_v3 *zwp_text_input_v3,
 
     /* 1. Delete existing pre-edit text */
     if (term->ime.preedit.cells != NULL) {
-        term_reset_ime(term);
+        term_ime_reset(term);
         render_refresh(term);
     }
 
@@ -337,6 +306,36 @@ ime_reset(struct seat *seat)
     ime_reset_commit(seat);
 }
 
+void
+ime_enable(struct seat *seat)
+{
+    struct terminal *term = seat->kbd_focus;
+    assert(term != NULL);
+
+    if (!term->ime.enabled)
+        return;
+
+    ime_reset(seat);
+
+    zwp_text_input_v3_enable(seat->wl_text_input);
+    zwp_text_input_v3_set_content_type(
+        seat->wl_text_input,
+        ZWP_TEXT_INPUT_V3_CONTENT_HINT_NONE,
+        ZWP_TEXT_INPUT_V3_CONTENT_PURPOSE_TERMINAL);
+
+    zwp_text_input_v3_commit(seat->wl_text_input);
+    seat->ime.serial++;
+}
+
+void
+ime_disable(struct seat *seat)
+{
+    ime_reset(seat);
+
+    zwp_text_input_v3_disable(seat->wl_text_input);
+    zwp_text_input_v3_commit(seat->wl_text_input);
+    seat->ime.serial++;
+}
 
 const struct zwp_text_input_v3_listener text_input_listener = {
     .enter = &enter,
@@ -349,6 +348,9 @@ const struct zwp_text_input_v3_listener text_input_listener = {
 
 #else /* !FOOT_IME_ENABLED */
 
+void ime_enable(struct seat *seat) {}
+void ime_disable(struct seat *seat) {}
+
 void ime_reset_preedit(struct seat *seat) {}
 void ime_reset_commit(struct seat *seat) {}
 void ime_reset(struct seat *seat) {}

ime.h

@@ -10,6 +10,9 @@ extern const struct zwp_text_input_v3_listener text_input_listener;
 
 struct seat;
 
+void ime_enable(struct seat *seat);
+void ime_disable(struct seat *seat);
+
 void ime_reset_preedit(struct seat *seat);
 void ime_reset_commit(struct seat *seat);
 void ime_reset(struct seat *seat);

pgo/pgo.c

@@ -126,6 +126,9 @@ extract_finish(struct extraction_context *context, char **text, size_t *len)
 void cmd_scrollback_up(struct terminal *term, int rows) {}
 void cmd_scrollback_down(struct terminal *term, int rows) {}
 
+void ime_enable(struct seat *seat) {}
+void ime_disable(struct seat *seat) {}
+
 int
 main(int argc, const char *const *argv)
 {

terminal.c

@@ -24,6 +24,7 @@
 #include "config.h"
 #include "extract.h"
 #include "grid.h"
+#include "ime.h"
 #include "quirks.h"
 #include "reaper.h"
 #include "render.h"
@@ -1116,6 +1117,11 @@ term_init(const struct config *conf, struct fdm *fdm, struct reaper *reaper,
         .shutdown_data = shutdown_data,
         .foot_exe = xstrdup(foot_exe),
         .cwd = xstrdup(cwd),
+#if defined(FOOT_IME_ENABLED) && FOOT_IME_ENABLED
+        .ime = {
+            .enabled = true,
+        },
+#endif
     };
 
     for (size_t i = 0; i < 4; i++) {
@@ -1403,7 +1409,7 @@ term_destroy(struct terminal *term)
     tll_free(term->alt.sixel_images);
     sixel_fini(term);
 
-    term_reset_ime(term);
+    term_ime_reset(term);
 
     free(term->foot_exe);
     free(term->cwd);
@@ -1559,6 +1565,10 @@ term_reset(struct terminal *term, bool hard)
         sixel_destroy(&it->item);
     tll_free(term->alt.sixel_images);
 
+#if defined(FOOT_IME_ENABLED) && FOOT_IME_ENABLED
+    term_ime_enable(term);
+#endif
+
     if (!hard)
         return;
 
@@ -2220,7 +2230,7 @@ term_kbd_focus_out(struct terminal *term)
 
 #if defined(FOOT_IME_ENABLED) && FOOT_IME_ENABLED
     if (term->ime.preedit.cells != NULL) {
-        term_reset_ime(term);
+        term_ime_reset(term);
         render_refresh(term);
     }
 #endif
@@ -2754,12 +2764,64 @@ term_view_to_text(const struct terminal *term, char **text, size_t *len)
     return rows_to_text(term, start, end, text, len);
 }
 
-void
+bool
-term_reset_ime(struct terminal *term)
+term_ime_is_enabled(const struct terminal *term)
 {
 #if defined(FOOT_IME_ENABLED) && FOOT_IME_ENABLED
-    free(term->ime.preedit.cells);
+    return term->ime.enabled;
-    term->ime.preedit.cells = NULL;
+#else
-    term->ime.preedit.count = 0;
+    return false;
+#endif
+}
+
+void
+term_ime_enable(struct terminal *term)
+{
+#if defined(FOOT_IME_ENABLED) && FOOT_IME_ENABLED
+    if (term->ime.enabled)
+        return;
+
+    LOG_DBG("IME enabled");
+
+    term->ime.enabled = true;
+    term_ime_reset(term);
+
+    /* IME is per seat - enable on all seat currenly focusing us */
+    tll_foreach(term->wl->seats, it) {
+        if (it->item.kbd_focus == term)
+            ime_enable(&it->item);
+    }
+#endif
+}
+
+void
+term_ime_disable(struct terminal *term)
+{
+#if defined(FOOT_IME_ENABLED) && FOOT_IME_ENABLED
+    if (!term->ime.enabled)
+        return;
+
+    LOG_DBG("IME disabled");
+
+    term->ime.enabled = false;
+    term_ime_reset(term);
+
+    /* IME is per seat - disable on all seat currenly focusing us */
+    tll_foreach(term->wl->seats, it) {
+        if (it->item.kbd_focus == term)
+            ime_disable(&it->item);
+    }
+#endif
+}
+
+void
+term_ime_reset(struct terminal *term)
+{
+#if defined(FOOT_IME_ENABLED) && FOOT_IME_ENABLED
+    if (term->ime.preedit.cells != NULL) {
+        free(term->ime.preedit.cells);
+        term->ime.preedit.cells = NULL;
+        term->ime.preedit.count = 0;
+    }
 #endif
 }

terminal.h

@@ -472,6 +472,7 @@ struct terminal {
 
 #if defined(FOOT_IME_ENABLED) && FOOT_IME_ENABLED
     struct {
+        bool enabled;
         struct {
             struct cell *cells;
             int count;
@@ -608,4 +609,7 @@ bool term_scrollback_to_text(
 bool term_view_to_text(
     const struct terminal *term, char **text, size_t *len);
 
-void term_reset_ime(struct terminal *term);
+bool term_ime_is_enabled(const struct terminal *term);
+void term_ime_enable(struct terminal *term);
+void term_ime_disable(struct terminal *term);
+void term_ime_reset(struct terminal *term);