Add primary selection support (#1729)

* Add support for primary selections

* Handle primary selection in `DocView`s

data/core/commands/doc.lua

@@ -93,6 +93,13 @@ local function cut_or_copy(delete)
   system.set_clipboard(full_text)
 end
 
+local function set_primary_selection(doc)
+  -- Doesn't work on Windows, so avoid spending time getting the text
+  if PLATFORM ~= "Windows" then
+    system.set_primary_selection(doc:get_selection_text())
+  end
+end
+
 local function split_cursor(dv, direction)
   local new_cursors = {}
   local dv_translate = direction < 0
@@ -297,6 +304,15 @@ local commands = {
     end
   end,
 
+  ["doc:paste-primary-selection"] = function(dv, x, y)
+    if type(x) == "number" and type(y) == "number" then
+      set_cursor(dv, x, y, "set")
+      -- Workaround to avoid that a middle mouse drag starts selecting
+      dv.mouse_selecting = nil
+    end
+    dv.doc:text_input(system.get_primary_selection() or "")
+  end,
+
   ["doc:newline"] = function(dv)
     for idx, line, col in dv.doc:get_selections(false, true) do
       local indent = dv.doc.lines[line]:match("^[\t ]*")
@@ -353,6 +369,7 @@ local commands = {
 
   ["doc:select-all"] = function(dv)
     dv.doc:set_selection(1, 1, math.huge, math.huge)
+    set_primary_selection(dv.doc)
     -- avoid triggering DocView:scroll_to_make_visible
     dv.last_line1 = 1
     dv.last_col1 = 1
@@ -365,6 +382,7 @@ local commands = {
       append_line_if_last_line(line2)
       dv.doc:set_selections(idx, line2 + 1, 1, line1, 1)
     end
+    set_primary_selection(dv.doc)
   end,
 
   ["doc:select-word"] = function(dv)
@@ -373,6 +391,7 @@ local commands = {
       local line2, col2 = translate.end_of_word(dv.doc, line1, col1)
       dv.doc:set_selections(idx, line2, col2, line1, col1)
     end
+    set_primary_selection(dv.doc)
   end,
 
   ["doc:join-lines"] = function(dv)
@@ -626,6 +645,7 @@ local commands = {
     local line2, col2 = dv:resolve_screen_position(x, y)
     dv.mouse_selecting = { line1, col1, nil }
     dv.doc:set_selection(line2, col2, line1, col1)
+    set_primary_selection(dv.doc)
   end,
 
   ["doc:create-cursor-previous-line"] = function(dv)
@@ -696,9 +716,16 @@ local translations = {
 }
 
 for name, obj in pairs(translations) do
-  commands["doc:move-to-" .. name] = function(dv) dv.doc:move_to(obj[name:gsub("-", "_")], dv) end
+  commands["doc:move-to-" .. name] = function(dv)
-  commands["doc:select-to-" .. name] = function(dv) dv.doc:select_to(obj[name:gsub("-", "_")], dv) end
+    dv.doc:move_to(obj[name:gsub("-", "_")], dv)
-  commands["doc:delete-to-" .. name] = function(dv) dv.doc:delete_to(obj[name:gsub("-", "_")], dv) end
+  end
+  commands["doc:select-to-" .. name] = function(dv)
+    dv.doc:select_to(obj[name:gsub("-", "_")], dv)
+    set_primary_selection(dv.doc)
+  end
+  commands["doc:delete-to-" .. name] = function(dv)
+    dv.doc:delete_to(obj[name:gsub("-", "_")], dv)
+  end
 end
 
 commands["doc:move-to-previous-char"] = function(dv)

data/core/keymap.lua

@@ -393,6 +393,7 @@ keymap.add_direct {
   ["1lclick"] = "doc:set-cursor",
   ["2lclick"] = { "doc:set-cursor-word", "emptyview:new-doc", "tabbar:new-doc" },
   ["3lclick"] = "doc:set-cursor-line",
+  ["mclick"] = "doc:paste-primary-selection",
   ["shift+left"] = "doc:select-to-previous-char",
   ["shift+right"] = "doc:select-to-next-char",
   ["shift+up"] = "doc:select-to-previous-line",

docs/api/system.lua

@@ -260,6 +260,18 @@ function system.get_clipboard() end
 ---@param text string
 function system.set_clipboard(text) end
 
+---
+---Retrieve the text currently stored in the primary selection.
+---
+---@return string
+function system.get_primary_selection() end
+
+---
+---Set the content of the primary selection.
+---
+---@param text string
+function system.set_primary_selection(text) end
+
 ---
 ---Get the process id of lite-xl itself.
 ---

src/api/system.c

@@ -897,6 +897,28 @@ static int f_set_clipboard(lua_State *L) {
 }
 
 
+static int f_get_primary_selection(lua_State *L) {
+#if SDL_VERSION_ATLEAST(2, 26, 0)
+  char *text = SDL_GetPrimarySelectionText();
+  if (!text) { return 0; }
+  lua_pushstring(L, text);
+  SDL_free(text);
+  return 1;
+#else
+  return 0;
+#endif
+}
+
+
+static int f_set_primary_selection(lua_State *L) {
+#if SDL_VERSION_ATLEAST(2, 26, 0)
+  const char *text = luaL_checkstring(L, 1);
+  SDL_SetPrimarySelectionText(text);
+#endif
+  return 0;
+}
+
+
 static int f_get_process_id(lua_State *L) {
 #ifdef _WIN32
   lua_pushinteger(L, GetCurrentProcessId());
@@ -1227,40 +1249,42 @@ static int f_setenv(lua_State* L) {
 
 
 static const luaL_Reg lib[] = {
-  { "poll_event",          f_poll_event          },
+  { "poll_event",            f_poll_event            },
-  { "wait_event",          f_wait_event          },
+  { "wait_event",            f_wait_event            },
-  { "set_cursor",          f_set_cursor          },
+  { "set_cursor",            f_set_cursor            },
-  { "set_window_title",    f_set_window_title    },
+  { "set_window_title",      f_set_window_title      },
-  { "set_window_mode",     f_set_window_mode     },
+  { "set_window_mode",       f_set_window_mode       },
-  { "get_window_mode",     f_get_window_mode     },
+  { "get_window_mode",       f_get_window_mode       },
-  { "set_window_bordered", f_set_window_bordered },
+  { "set_window_bordered",   f_set_window_bordered   },
-  { "set_window_hit_test", f_set_window_hit_test },
+  { "set_window_hit_test",   f_set_window_hit_test   },
-  { "get_window_size",     f_get_window_size     },
+  { "get_window_size",       f_get_window_size       },
-  { "set_window_size",     f_set_window_size     },
+  { "set_window_size",       f_set_window_size       },
-  { "set_text_input_rect", f_set_text_input_rect },
+  { "set_text_input_rect",   f_set_text_input_rect   },
-  { "clear_ime",           f_clear_ime           },
+  { "clear_ime",             f_clear_ime             },
-  { "window_has_focus",    f_window_has_focus    },
+  { "window_has_focus",      f_window_has_focus      },
-  { "raise_window",        f_raise_window        },
+  { "raise_window",          f_raise_window          },
-  { "show_fatal_error",    f_show_fatal_error    },
+  { "show_fatal_error",      f_show_fatal_error      },
-  { "rmdir",               f_rmdir               },
+  { "rmdir",                 f_rmdir                 },
-  { "chdir",               f_chdir               },
+  { "chdir",                 f_chdir                 },
-  { "mkdir",               f_mkdir               },
+  { "mkdir",                 f_mkdir                 },
-  { "list_dir",            f_list_dir            },
+  { "list_dir",              f_list_dir              },
-  { "absolute_path",       f_absolute_path       },
+  { "absolute_path",         f_absolute_path         },
-  { "get_file_info",       f_get_file_info       },
+  { "get_file_info",         f_get_file_info         },
-  { "get_clipboard",       f_get_clipboard       },
+  { "get_clipboard",         f_get_clipboard         },
-  { "set_clipboard",       f_set_clipboard       },
+  { "set_clipboard",         f_set_clipboard         },
-  { "get_process_id",      f_get_process_id      },
+  { "get_primary_selection", f_get_primary_selection },
-  { "get_time",            f_get_time            },
+  { "set_primary_selection", f_set_primary_selection },
-  { "sleep",               f_sleep               },
+  { "get_process_id",        f_get_process_id        },
-  { "exec",                f_exec                },
+  { "get_time",              f_get_time              },
-  { "fuzzy_match",         f_fuzzy_match         },
+  { "sleep",                 f_sleep                 },
-  { "set_window_opacity",  f_set_window_opacity  },
+  { "exec",                  f_exec                  },
-  { "load_native_plugin",  f_load_native_plugin  },
+  { "fuzzy_match",           f_fuzzy_match           },
-  { "path_compare",        f_path_compare        },
+  { "set_window_opacity",    f_set_window_opacity    },
-  { "get_fs_type",         f_get_fs_type         },
+  { "load_native_plugin",    f_load_native_plugin    },
-  { "text_input",          f_text_input          },
+  { "path_compare",          f_path_compare          },
-  { "setenv",              f_setenv              },
+  { "get_fs_type",           f_get_fs_type           },
+  { "text_input",            f_text_input            },
+  { "setenv",                f_setenv                },
   { NULL, NULL }
 };