add(feature): toggle boolean options with cli flag (#855)

add the ability to toggle boolean options with a cli flag:

example:
    if the pane frames are turned off in the config file,
    then passing in the `--no-pane-frames` flag will toggle the
    pane frames on

6 files changed, 106 insertions, 14 deletions

diff --git a/src/commands.rs b/src/commands.rs
index da97cee87..aec3970e0 100644
--- a/src/commands.rs
+++ b/src/commands.rs
@@ -176,7 +176,7 @@ pub(crate) fn start_client(opts: CliArgs) {
     })) = opts.command.clone()
     {
         let config_options = match options {
-            Some(SessionCommand::Options(o)) => config_options.merge(o),
+            Some(SessionCommand::Options(o)) => config_options.merge_from_cli(o.into()),
             None => config_options,
         };
 
diff --git a/zellij-client/src/input_handler.rs b/zellij-client/src/input_handler.rs
index d07c2caa8..c2d93a0cf 100644
--- a/zellij-client/src/input_handler.rs
+++ b/zellij-client/src/input_handler.rs
@@ -63,7 +63,7 @@ impl InputHandler {
         let mut err_ctx = OPENCALLS.with(|ctx| *ctx.borrow());
         err_ctx.add_call(ContextType::StdinHandler);
         let alt_left_bracket = vec![27, 91];
-        if !self.options.disable_mouse_mode {
+        if !self.options.disable_mouse_mode.unwrap_or_default() {
             self.os_input.enable_mouse();
         }
         loop {
diff --git a/zellij-server/src/lib.rs b/zellij-server/src/lib.rs
index 38e469a89..036d41f0a 100644
--- a/zellij-server/src/lib.rs
+++ b/zellij-server/src/lib.rs
@@ -523,7 +523,7 @@ fn init_session(
     let data_dir = opts.data_dir.unwrap_or_else(get_default_data_dir);
 
     let capabilities = PluginCapabilities {
-        arrow_fonts: config_options.simplified_ui,
+        arrow_fonts: config_options.simplified_ui.unwrap_or_default(),
     };
 
     let default_shell = config_options.default_shell.clone().map(|command| {
diff --git a/zellij-server/src/screen.rs b/zellij-server/src/screen.rs
index fb225f78a..2fa964271 100644
--- a/zellij-server/src/screen.rs
+++ b/zellij-server/src/screen.rs
@@ -560,7 +560,7 @@ pub(crate) fn screen_thread_main(
     config_options: Box<Options>,
 ) {
     let capabilities = config_options.simplified_ui;
-    let draw_pane_frames = !config_options.no_pane_frames;
+    let draw_pane_frames = !config_options.no_pane_frames.unwrap_or_default();
 
     let mut screen = Screen::new(
         bus,
@@ -570,7 +570,7 @@ pub(crate) fn screen_thread_main(
             config_options.default_mode.unwrap_or_default(),
             client_attributes.palette,
             PluginCapabilities {
-                arrow_fonts: capabilities,
+                arrow_fonts: capabilities.unwrap_or_default(),
             },
         ),
         draw_pane_frames,
diff --git a/zellij-utils/src/cli.rs b/zellij-utils/src/cli.rs
index 78615d929..2c1aeba37 100644
--- a/zellij-utils/src/cli.rs
+++ b/zellij-utils/src/cli.rs
@@ -1,6 +1,8 @@
-use crate::consts::{ZELLIJ_CONFIG_DIR_ENV, ZELLIJ_CONFIG_FILE_ENV};
-use crate::input::options::Options;
 use crate::setup::Setup;
+use crate::{
+    consts::{ZELLIJ_CONFIG_DIR_ENV, ZELLIJ_CONFIG_FILE_ENV},
+    input::options::CliOptions,
+};
 use serde::{Deserialize, Serialize};
 use std::path::PathBuf;
 use structopt::StructOpt;
@@ -51,7 +53,7 @@ pub struct CliArgs {
 pub enum Command {
     /// Change the behaviour of zellij
     #[structopt(name = "options")]
-    Options(Options),
+    Options(CliOptions),
 
     /// Setup zellij and check its configuration
     #[structopt(name = "setup")]
@@ -66,7 +68,7 @@ pub enum Command {
 pub enum SessionCommand {
     /// Change the behaviour of zellij
     #[structopt(name = "options")]
-    Options(Options),
+    Options(CliOptions),
 }
 
 #[derive(Debug, StructOpt, Clone, Serialize, Deserialize)]
diff --git a/zellij-utils/src/input/options.rs b/zellij-utils/src/input/options.rs
index 94994e1e3..c23267fb6 100644
--- a/zellij-utils/src/input/options.rs
+++ b/zellij-utils/src/input/options.rs
@@ -35,12 +35,14 @@ impl FromStr for OnForceClose {
 #[derive(Clone, Default, Debug, PartialEq, Deserialize, Serialize, StructOpt)]
 /// Options that can be set either through the config file,
 /// or cli flags - cli flags should take precedence over the config file
+/// TODO: In order to correctly parse boolean flags, this is currently split
+/// into Options and CliOptions, this could be a good canditate for a macro
 pub struct Options {
     /// Allow plugins to use a more simplified layout
     /// that is compatible with more fonts
     #[structopt(long)]
     #[serde(default)]
-    pub simplified_ui: bool,
+    pub simplified_ui: Option<bool>,
     /// Set the default theme
     #[structopt(long)]
     pub theme: Option<String>,
@@ -57,10 +59,10 @@ pub struct Options {
     #[structopt(long)]
     #[serde(default)]
     /// Disable handling of mouse events
-    pub disable_mouse_mode: bool,
+    pub disable_mouse_mode: Option<bool>,
     #[structopt(long)]
     #[serde(default)]
-    pub no_pane_frames: bool,
+    pub no_pane_frames: Option<bool>,
     /// Set behaviour on force close (quit or detach)
     #[structopt(long)]
     pub on_force_close: Option<OnForceClose>,
@@ -79,7 +81,41 @@ impl Options {
     /// will supercede a `Some` in `self`
     // TODO: Maybe a good candidate for a macro?
     pub fn merge(&self, other: Options) -> Options {
-        let merge_bool = |opt_other, opt_self| if opt_other { true } else { opt_self };
+        let disable_mouse_mode = other.disable_mouse_mode.or(self.disable_mouse_mode);
+        let no_pane_frames = other.no_pane_frames.or(self.no_pane_frames);
+        let simplified_ui = other.simplified_ui.or(self.simplified_ui);
+        let default_mode = other.default_mode.or(self.default_mode);
+        let default_shell = other.default_shell.or_else(|| self.default_shell.clone());
+        let layout_dir = other.layout_dir.or_else(|| self.layout_dir.clone());
+        let theme = other.theme.or_else(|| self.theme.clone());
+        let on_force_close = other.on_force_close.or(self.on_force_close);
+
+        Options {
+            simplified_ui,
+            theme,
+            default_mode,
+            default_shell,
+            layout_dir,
+            disable_mouse_mode,
+            no_pane_frames,
+            on_force_close,
+        }
+    }
+
+    /// Merges two [`Options`] structs,
+    /// - `Some` in `other` will supercede a `Some` in `self`
+    /// - `Some(bool)` in `other` will toggle a `Some(bool)` in `self`
+    // TODO: Maybe a good candidate for a macro?
+    pub fn merge_from_cli(&self, other: Options) -> Options {
+        let merge_bool = |opt_other: Option<bool>, opt_self: Option<bool>| {
+            if opt_other.is_some() ^ opt_self.is_some() {
+                opt_other.or(opt_self)
+            } else if opt_other.is_some() && opt_self.is_some() {
+                Some(opt_other.unwrap() ^ opt_self.unwrap())
+            } else {
+                None
+            }
+        };
 
         let simplified_ui = merge_bool(other.simplified_ui, self.simplified_ui);
         let disable_mouse_mode = merge_bool(other.disable_mouse_mode, self.disable_mouse_mode);
@@ -105,9 +141,63 @@ impl Options {
 
     pub fn from_cli(&self, other: Option<Command>) -> Options {
         if let Some(Command::Options(options)) = other {
-            Options::merge(self, options)
+            Options::merge_from_cli(self, options.into())
         } else {
             self.to_owned()
         }
     }
 }
+
+#[derive(Clone, Default, Debug, PartialEq, StructOpt, Serialize, Deserialize)]
+/// Options that can be set through cli flags
+/// boolean flags end up toggling boolean options in `Options`
+pub struct CliOptions {
+    /// Allow plugins to use a more simplified layout
+    /// that is compatible with more fonts
+    #[structopt(long)]
+    pub simplified_ui: bool,
+    /// Set the default theme
+    #[structopt(long)]
+    pub theme: Option<String>,
+    /// Set the default mode
+    #[structopt(long)]
+    pub default_mode: Option<InputMode>,
+    /// Set the default shell
+    #[structopt(long, parse(from_os_str))]
+    pub default_shell: Option<PathBuf>,
+    /// Set the layout_dir, defaults to
+    /// subdirectory of config dir
+    #[structopt(long, parse(from_os_str))]
+    pub layout_dir: Option<PathBuf>,
+    #[structopt(long)]
+    /// Disable handling of mouse events
+    pub disable_mouse_mode: bool,
+    #[structopt(long)]
+    pub no_pane_frames: bool,
+    /// Set behaviour on force close (quit or detach)
+    #[structopt(long)]
+    pub on_force_close: Option<OnForceClose>,
+}
+
+impl From<CliOptions> for Options {
+    fn from(cli_options: CliOptions) -> Self {
+        let handle_bool = |bool| {
+            if bool {
+                Some(true)
+            } else {
+                None
+            }
+        };
+
+        Self {
+            simplified_ui: handle_bool(cli_options.simplified_ui),
+            theme: cli_options.theme,
+            default_mode: cli_options.default_mode,
+            default_shell: cli_options.default_shell,
+            layout_dir: cli_options.layout_dir,
+            disable_mouse_mode: handle_bool(cli_options.disable_mouse_mode),
+            no_pane_frames: handle_bool(cli_options.no_pane_frames),
+            on_force_close: cli_options.on_force_close,
+        }
+    }
+}