feat(layout): 'Window' ordering ability (#118)

* Window ordering ability

Added ability to change display order of the windows using tab. Added a help tooltip.

* fix redundant clone

* fix fmt check

* cargo fmt fix 2

* Fixed help layout and added tests

* Fix fmt check

3 files changed, 26 insertions, 9 deletions

diff --git a/src/display/components/help_text.rs b/src/display/components/help_text.rs
index 2b49551..7d66ad8 100644
--- a/src/display/components/help_text.rs
+++ b/src/display/components/help_text.rs
@@ -9,10 +9,14 @@ pub struct HelpText {
     pub show_dns: bool,
 }
 
-const TEXT_WHEN_PAUSED: &str = " Press <SPACE> to resume";
-const TEXT_WHEN_NOT_PAUSED: &str = " Press <SPACE> to pause";
+const FIRST_WIDTH_BREAKPOINT: u16 = 76;
+const SECOND_WIDTH_BREAKPOINT: u16 = 54;
+
+const TEXT_WHEN_PAUSED: &str = " Press <SPACE> to resume.";
+const TEXT_WHEN_NOT_PAUSED: &str = " Press <SPACE> to pause.";
 const TEXT_WHEN_DNS_NOT_SHOWN: &str = " (DNS queries hidden).";
 const TEXT_WHEN_DNS_SHOWN: &str = " (DNS queries shown).";
+const TEXT_TAB_TIP: &str = " Use <TAB> to rearrange tables.";
 
 impl HelpText {
     pub fn render(&self, frame: &mut Frame<impl Backend>, rect: Rect) {
@@ -23,14 +27,22 @@ impl HelpText {
                 TEXT_WHEN_NOT_PAUSED
             };
 
-            let dns_content = if self.show_dns {
+            let dns_content = if rect.width <= FIRST_WIDTH_BREAKPOINT {
+                ""
+            } else if self.show_dns {
                 TEXT_WHEN_DNS_SHOWN
             } else {
                 TEXT_WHEN_DNS_NOT_SHOWN
             };
 
+            let tab_text = if rect.width <= SECOND_WIDTH_BREAKPOINT {
+                ""
+            } else {
+                TEXT_TAB_TIP
+            };
+
             [Text::styled(
-                format!("{}{}", pause_content, dns_content),
+                format!("{}{}{}", pause_content, tab_text, dns_content),
                 Style::default().modifier(Modifier::BOLD),
             )]
         };
diff --git a/src/display/components/layout.rs b/src/display/components/layout.rs
index c047774..79186cd 100644
--- a/src/display/components/layout.rs
+++ b/src/display/components/layout.rs
@@ -99,12 +99,12 @@ impl<'a> Layout<'a> {
             self.build_three_children_layout(rect)
         }
     }
-    pub fn render(&self, frame: &mut Frame<impl Backend>, rect: Rect) {
+    pub fn render(&self, frame: &mut Frame<impl Backend>, rect: Rect, ui_offset: usize) {
         let (top, app, bottom) = top_app_and_bottom_split(rect);
         let layout_slots = self.build_layout(app);
         for i in 0..layout_slots.len() {
             if let Some(rect) = layout_slots.get(i) {
-                if let Some(child) = self.children.get(i) {
+                if let Some(child) = self.children.get((i + ui_offset) % self.children.len()) {
                     child.render(frame, *rect);
                 }
             }
diff --git a/src/display/ui.rs b/src/display/ui.rs
index 68f133a..600a6db 100644
--- a/src/display/ui.rs
+++ b/src/display/ui.rs
@@ -61,7 +61,7 @@ where
                 display_connection_string(
                     connection,
                     ip_to_host,
-                    &connection_network_data.interface_name
+                    &connection_network_data.interface_name,
                 ),
                 connection_network_data.total_bytes_uploaded,
                 connection_network_data.total_bytes_downloaded,
@@ -79,7 +79,7 @@ where
             ));
         }
     }
-    pub fn draw(&mut self, paused: bool, show_dns: bool) {
+    pub fn draw(&mut self, paused: bool, show_dns: bool, ui_offset: usize) {
         let state = &self.state;
         let children = self.get_tables_to_display();
         self.terminal
@@ -95,7 +95,7 @@ where
                     children,
                     footer: help_text,
                 };
-                layout.render(&mut frame, size);
+                layout.render(&mut frame, size, ui_offset);
             })
             .unwrap();
     }
@@ -127,6 +127,11 @@ where
         }
         children
     }
+
+    pub fn get_table_count(&self) -> usize {
+        self.get_tables_to_display().len()
+    }
+
     pub fn update_state(
         &mut self,
         connections_to_procs: HashMap<LocalSocket, String>,