feat(ui): initial mouse support (#448)

* Initial mouse support

* enable mouse support (termion MouseTerminal)
* handle scroll up and down events

* Allow enabling/disabling of mouse reporting

Store the mouse terminal on OsInputOutput

* WIP: switch pane focus with mouse

* testing to get mouse character selection

* wip mouse selection

* wip: mouse selection

- initial handling of mouse events for
  text selection within a pane
- wide characters currently problematic
- selection is not highlighted

* highlight currently selected text

* improve get currently selected text from TerminalPane

* copy selection to clipboard (wayland only for now)

* Add missing set_should_render on selection update

* Improve text selection

- Strip whitespace from end of lines
- Insert newlines when selection spans multiple lines

* Simplify selection logic

- Remove Range struct
- Selection is not an Option anymore, it's empty when start == end

* copy selection to clipboard with OSC-52 sequence

* Improve text selection with multiple panes

- Constrain mouse hold and release events to currently active pane
- Fix calculation of columns with side by side panes

* fix for PositionAndSize changes

* Fix mouse selection with full screen pane.

- Transform mouse event positions to relative when passing to pane.

* Move selection to grid, rework highlighting.

- Mark selected lines for update in grid output buffer, for now in the
  simplest way possible, but can be made more efficient by calculating
  changed lines only.
- Clear selection on pane resize.
- Re-add logic to forward mouse hold and release events only to
  currently active pane.

* Tidy up selection

- add method to get selection line range
- add method to sort the current selection

* Grid: move current selection up/down when scrolling

- Make the selection work with lines in lines_above and lines_below
- Todo: update selection end when scrolling with mouse button being held
- Todo: figure out how to move selection when new characters are added.

* Grid: move selection when new lines are added

* Keep track of selection being active

- Handle the selection growing/shrinking when scrolling with mouse
  button held down but not yet released.

* Improve selection end with multiple panes

* Tidying up

- remove logging statements, unused code

* Add some unit tests for selection, move position to zellij-utils

* Change Position::new to take i32 for line

* Grid: add unit tests for copy from selection

* add basic integration test for mouse pane focus

* Add basic integration test for mouse scroll

* Use color from palette for selection rendering

* Improve performance of selection render

- Try to minimize lines to update on selection start/update/end

* fixes for updated start method

* fix lines not in viewport being marked for rendering

- the previous optimization to grid selection rendering was always
adding the lines at the extremes of previous selection, causing problems
when scrolling up or down
- make sure to only add lines in viewport

* Disable mouse mode on exit

* use saturating_sub for usize subtractions

* copy selection to clipboard on mouse release

* disable mouse on exit after error

* remove left-over comments

* remove copy keybinding

* add default impl for selection methods in Pane

- remove the useless methods from Impl Pane in PluginPane

* move line diff between selections to selection

* add option to disable mouse mode

* Allow scrolling with mouse while selecting.

* move action repeater to os_input_output, change timeout to 10ms

- change repeater to take an action instead of a position with hardcoded
action

* replace mouse mode integration tests with e2e tests

* cleanup

* cleanup

* check if mouse mode is disabled from merged options

* fix missing changes in tests, cleanup

1 files changed, 1 insertions, 0 deletions

diff --git a/zellij-client/Cargo.toml b/zellij-client/Cargo.toml
index 9b04104b3..4ca49bccf 100644
--- a/zellij-client/Cargo.toml
+++ b/zellij-client/Cargo.toml
@@ -9,6 +9,7 @@ license = "MIT"
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
+mio = "0.7.11"
 termbg = "0.2.3"
 zellij-utils = { path = "../zellij-utils/", version = "0.14.0" }