GSoc-2021-proposal-draft-Project_Stuff_Only.

This is a draft for the GSoc proposal of godot Organisation working on Command palette project.

user scenarios

user can search a command from the line-edit in thee command palette.
user can execute a command that he searched.
user can view shortcut for a command if available.
user can search file or scene.
user can view all the aviable commands with a fuzzy-search result.
user can change workspace.

Presentation and integration

user uses a shortcut for command palette ctrl + shift + p or cmd + shift + p to open a Modal-Dialog, Which has a line-edit to search and list-view that contains fuzzy-search result of the above searched command or file.
Modal-Dialog mentioned doesn't have any close button and can be closed by either Esc button or changing the focus to other view.
first retrieved search result is selected by default and pressing return or enter key would execute that command or open that scence or file.

1.Some Features
- use ? to get available command filters like :
  - > for editor commands. (Editor Main Menu Settings)
  - (prefixed with nothing) search for Resources.
- Example:>op will search and retrieve all the commands with name containing op.
- Navigate Workspace (2D, 3D, Script, AssetLib).
2.Dependencies

Modal-Dialog :
```
    Should use available GUI to make something like described in Wiki.
```
List-View :
```
    May be I can use popup-menu but should think of something else.
```

Architecture

Priliminaries :

1.Commands / Actions : It is a reference of Callable(Function pointer) that calls some specific function when executed.

To Have a Functional Command Palette we need :

A Data-Structre to Store Callable and Arguments and Retreive it by some string.

A EditorActions Class is made and Store actions with a HashMap where String type as Key and Storing a Pair of Callable and Vector for arguments (HashMap<String, Pair<Callable, Vector<Variant>> callables). but EditorAction has some other big plans #70. So to make a difference between Command Palette actions and other Editor actions we have a Vector<String> palette_action which keep track of all Command palette actions. and another Hashmap for shortcuts HashMap<String, Shortcut>.
Register EditorActions.

So this can be done in EditorNode where most of the Editor code lies. where i call EditorAction::add_palette_action("action_name", callable_mp(this, func), varray(arg1,arg2..), [Shortcut]);.
We need a way to search and execute for a Command from avaiable commands.

A CommandPalette Class is made which contains all the UI like line-edit, List-view. when we start searching something if it's start with > it will start searching EditorAction commands i.e it will retreive action_names from EditorActions::palete_actions otherwise it will just Search for Resource just like Quick Open Resource. when Desired action is selected it emits execute_command signal or open_file in case of resource.
Execute the Command once the desired command is selected.

So execute_command signal is connected to EditorNode::_execute_command() which just calls EditorAction::_execute_action(selected_command) and open_file signal connects to EditorNode::_open_file() which opens file same as Quick Open Resource.