feat: delete selected candidate

src/rime/context.cc

@@ -123,19 +123,32 @@ bool Context::Select(size_t index) {
   return false;
 }
 
-bool Context::DeleteCurrentSelection() {
+bool Context::DeleteCandidate(function<an<Candidate> (Segment& seg)> get_candidate) {
   if (composition_.empty())
-    return false;
-  Segment& seg(composition_.back());
-  if (auto cand = seg.GetSelectedCandidate()) {
-    DLOG(INFO) << "Deleting: '" << cand->text()
-               << "', selected_index = " << seg.selected_index;
-    delete_notifier_(this);
-    return true;  // CAVEAT: this doesn't mean anything is deleted for sure
+      return false;
+  if (auto cand = get_candidate(seg)) {
+      DLOG(INFO) << "Deleting: '" << cand->text()
+                 << "', index = " << index;
+      delete_notifier_(this);
+      return true;  // CAVEAT: this doesn't mean anything is deleted for sure
   }
   return false;
 }
 
+bool Context::DeleteCandidate(size_t index) {
+  return DeleteCandidate(
+      [index](Segment& seg) {
+        return seg.GetCandidateAt(index);
+      });
+}
+
+bool Context::DeleteCurrentSelection() {
+  return DeleteCandidate(
+      [](Segment& seg) {
+        return seg.GetSelectedCandidate();
+      });
+}
+
 bool Context::ConfirmCurrentSelection() {
   if (composition_.empty())
     return false;

src/rime/context.h

@@ -45,6 +45,7 @@ class Context {
 
   // return false if there is no candidate at index
   bool Select(size_t index);
+  bool DeleteCandidate(size_t index);
   // return false if there's no candidate for current segment
   bool ConfirmCurrentSelection();
   bool DeleteCurrentSelection();

src/rime_api.cc

@@ -1051,17 +1051,17 @@ size_t RimeGetCaretPos(RimeSessionId session_id) {
   return ctx->caret_pos();
 }
 
-Bool RimeSelectCandidate(RimeSessionId session_id, size_t index) {
+static bool do_with_candidate(RimeSessionId session_id, size_t index, bool (Context::* verb)(size_t index)) {
   an<Session> session(Service::instance().GetSession(session_id));
   if (!session)
     return False;
   Context *ctx = session->context();
   if (!ctx)
     return False;
-  return Bool(ctx->Select(index));
+  return Bool(ctx->*verb(index));
 }
 
-Bool RimeSelectCandidateOnCurrentPage(RimeSessionId session_id, size_t index) {
+static bool do_with_candidate_on_current_page(RimeSessionId session_id, size_t index, bool (Context::* verb)(size_t index)) {
   an<Session> session(Service::instance().GetSession(session_id));
   if (!session)
     return False;
@@ -1076,13 +1076,29 @@ Bool RimeSelectCandidateOnCurrentPage(RimeSessionId session_id, size_t index) {
     return False;
   const auto& seg(ctx->composition().back());
   size_t page_start = seg.selected_index / page_size * page_size;
-  return Bool(ctx->Select(page_start + index));
+  return (ctx->*verb)(page_start + index);
+}
+
+Bool RimeSelectCandidate(RimeSessionId session_id, size_t index) {
+  return do_with_candidate(session_id, index, Select);
+}
+
+Bool RimeSelectCandidateOnCurrentPage(RimeSessionId session_id, size_t index) {
+  return do_with_candidate_on_current_page(session_id, index, Select);
 }
 
 const char* RimeGetVersion() {
   return RIME_VERSION;
 }
 
+Bool RimeDeleteCandidate(RimeSessionId session_id, size_t index) {
+  return do_with_candidate(session_id, index, DeleteCandidate);
+}
+
+Bool RimeDeleteCandidateOnCurrentPage(RimeSessionId session_id, size_t index) {
+  return do_with_candidate_on_current_page(session_id, index, DeleteCandidate);
+}
+
 void RimeSetCaretPos(RimeSessionId session_id, size_t caret_pos) {
   an<Session> session(Service::instance().GetSession(session_id));
   if (!session)
@@ -1170,9 +1186,11 @@ RIME_API RimeApi* rime_get_api() {
     s_api.get_input = &RimeGetInput;
     s_api.get_caret_pos = &RimeGetCaretPos;
     s_api.select_candidate = &RimeSelectCandidate;
+    s_api.delete_candidate = &RimeDeleteCandidate;
     s_api.get_version = &RimeGetVersion;
     s_api.set_caret_pos = &RimeSetCaretPos;
     s_api.select_candidate_on_current_page = &RimeSelectCandidateOnCurrentPage;
+    s_api.delete_candidate_on_current_page = &RimeDeleteCandidateOnCurrentPage;
     s_api.candidate_list_begin = &RimeCandidateListBegin;
     s_api.candidate_list_next = &RimeCandidateListNext;
     s_api.candidate_list_end = &RimeCandidateListEnd;

src/rime_api.h

@@ -550,6 +550,11 @@ typedef struct rime_api_t {
   void (*commit_proto)(RimeSessionId session_id, RIME_PROTO_BUILDER* commit_builder);
   void (*context_proto)(RimeSessionId session_id, RIME_PROTO_BUILDER* context_builder);
   void (*status_proto)(RimeSessionId session_id, RIME_PROTO_BUILDER* status_builder);
+
+  //! delete a candidate at the given index in candidate list.
+  Bool (*delete_candidate)(RimeSessionId session_id, size_t index);
+  //! delete a candidate from current page.
+  Bool (*delete_candidate_on_current_page)(RimeSessionId session_id, size_t index);
 } RimeApi;
 
 //! API entry