refactor: don't draw header if too short

5 files changed, 207 insertions, 188 deletions

diff --git a/src/app/states.rs b/src/app/states.rs
index 5d3ace9c..ebb28996 100644
--- a/src/app/states.rs
+++ b/src/app/states.rs
@@ -117,9 +117,7 @@ impl TableComponentState {
 
     /// Calculates widths for the columns for this table.
     ///
-    /// * `total_width` is the, well, total width available.  **NOTE:** This function automatically
-    /// takes away 2 from the width as part of the left/right
-    /// bounds.
+    /// * `total_width` is the, well, total width available.
     /// * `left_to_right` is a boolean whether to go from left to right if true, or right to left if
     ///   false.
     ///
@@ -128,71 +126,68 @@ impl TableComponentState {
         use itertools::Either;
         use std::cmp::{max, min};
 
-        if total_width > 2 {
-            let initial_width = total_width - 2;
-            let mut total_width_left = initial_width;
+        let mut total_width_left = total_width;
 
-            let column_widths = &mut self.calculated_widths;
-            *column_widths = vec![0; self.columns.len()];
+        let column_widths = &mut self.calculated_widths;
+        *column_widths = vec![0; self.columns.len()];
 
-            let columns = if left_to_right {
-                Either::Left(self.columns.iter().enumerate())
-            } else {
-                Either::Right(self.columns.iter().enumerate().rev())
-            };
-
-            for (itx, column) in columns {
-                match &column.width_bounds {
-                    WidthBounds::Soft {
-                        min_width,
-                        desired,
-                        max_percentage,
-                    } => {
-                        let soft_limit = max(
-                            if let Some(max_percentage) = max_percentage {
-                                // Rust doesn't have an `into()` or `try_into()` for floats to integers???
-                                ((*max_percentage * f32::from(initial_width)).ceil()) as u16
-                            } else {
-                                *desired
-                            },
-                            *min_width,
-                        );
-                        let space_taken = min(min(soft_limit, *desired), total_width_left);
-
-                        if *min_width > space_taken {
-                            break;
+        let columns = if left_to_right {
+            Either::Left(self.columns.iter().enumerate())
+        } else {
+            Either::Right(self.columns.iter().enumerate().rev())
+        };
+
+        for (itx, column) in columns {
+            match &column.width_bounds {
+                WidthBounds::Soft {
+                    min_width,
+                    desired,
+                    max_percentage,
+                } => {
+                    let soft_limit = max(
+                        if let Some(max_percentage) = max_percentage {
+                            // Rust doesn't have an `into()` or `try_into()` for floats to integers???
+                            ((*max_percentage * f32::from(total_width)).ceil()) as u16
                         } else {
-                            total_width_left = total_width_left.saturating_sub(space_taken + 1);
-                            column_widths[itx] = space_taken;
-                        }
+                            *desired
+                        },
+                        *min_width,
+                    );
+                    let space_taken = min(min(soft_limit, *desired), total_width_left);
+
+                    if *min_width > space_taken {
+                        break;
+                    } else {
+                        total_width_left = total_width_left.saturating_sub(space_taken + 1);
+                        column_widths[itx] = space_taken;
                     }
-                    WidthBounds::Hard(width) => {
-                        let space_taken = min(*width, total_width_left);
+                }
+                WidthBounds::Hard(width) => {
+                    let space_taken = min(*width, total_width_left);
 
-                        if *width > space_taken {
-                            break;
-                        } else {
-                            total_width_left = total_width_left.saturating_sub(space_taken + 1);
-                            column_widths[itx] = space_taken;
-                        }
+                    if *width > space_taken {
+                        break;
+                    } else {
+                        total_width_left = total_width_left.saturating_sub(space_taken + 1);
+                        column_widths[itx] = space_taken;
                     }
                 }
             }
+        }
 
-            while let Some(0) = column_widths.last() {
-                column_widths.pop();
-            }
+        while let Some(0) = column_widths.last() {
+            column_widths.pop();
+        }
 
-            if !column_widths.is_empty() {
-                // Redistribute remaining.
-                let amount_per_slot = total_width_left / column_widths.len() as u16;
-                total_width_left %= column_widths.len() as u16;
-                for (index, width) in column_widths.iter_mut().enumerate() {
-                    if index < total_width_left.into() {
-                        *width += amount_per_slot + 1;
-                    } else {
-                        *width += amount_per_slot;
-                    }
+        if !column_widths.is_empty() {
+            // Redistribute remaining.
+            let amount_per_slot = total_width_left / column_widths.len() as u16;
+            total_width_left %= column_widths.len() as u16;
+            for (index, width) in column_widths.iter_mut().enumerate() {
+                if index < total_width_left.into() {
+                    *width += amount_per_slot + 1;
+                } else {
+                    *width += amount_per_slot;
                 }
             }
         }
diff --git a/src/canvas/components/text_table.rs b/src/canvas/components/text_table.rs
index 767b8e6c..86cc5d1b 100644
--- a/src/canvas/components/text_table.rs
+++ b/src/canvas/components/text_table.rs
@@ -19,7 +19,6 @@ use crate::{
 
 pub struct TextTable<'a> {
     pub table_gap: u16,
-    pub table_height_offset: u16,
     pub is_force_redraw: bool,
     pub recalculate_column_widths: bool,
 
@@ -100,71 +99,23 @@ impl<'a> TextTable<'a> {
         &self, f: &mut Frame<'_, B>, draw_loc: Rect, state: &mut TableComponentState,
         table_data: &TableData,
     ) -> Rect {
-        let table_gap = if draw_loc.height < TABLE_GAP_HEIGHT_LIMIT {
-            0
-        } else {
-            self.table_gap
-        };
+        let margined_draw_loc = Layout::default()
+            .constraints([Constraint::Percentage(100)])
+            .horizontal_margin(if self.is_on_widget || self.draw_border {
+                0
+            } else {
+                1
+            })
+            .direction(Direction::Horizontal)
+            .split(draw_loc)[0];
 
-        let sliced_vec = {
-            let num_rows = usize::from(
-                (draw_loc.height + 1 - table_gap).saturating_sub(self.table_height_offset),
-            );
-            let start = get_start_position(
-                num_rows,
-                &state.scroll_direction,
-                &mut state.scroll_bar,
-                state.current_scroll_position,
-                self.is_force_redraw,
+        let disk_block = if self.draw_border {
+            let title = self.generate_title(
+                draw_loc,
+                state.current_scroll_position.saturating_add(1),
+                table_data.data.len(),
             );
-            let end = min(table_data.data.len(), start + num_rows + 1);
-            state
-                .table_state
-                .select(Some(state.current_scroll_position.saturating_sub(start)));
-            &table_data.data[start..end]
-        };
 
-        // Calculate widths
-        if self.recalculate_column_widths {
-            state
-                .columns
-                .iter_mut()
-                .zip(&table_data.row_widths)
-                .for_each(|(column, data_width)| match &mut column.width_bounds {
-                    app::WidthBounds::Soft {
-                        min_width: _,
-                        desired,
-                        max_percentage: _,
-                    } => {
-                        *desired = std::cmp::max(column.name.len(), *data_width) as u16;
-                    }
-                    app::WidthBounds::Hard(_width) => {}
-                });
-
-            state.calculate_column_widths(draw_loc.width, self.left_to_right);
-        }
-
-        let columns = &state.columns;
-        let widths = &state.calculated_widths;
-        // TODO: Maybe truncate this too?
-        let header = Row::new(columns.iter().map(|c| Text::raw(c.name.as_ref())))
-            .style(self.header_style)
-            .bottom_margin(table_gap);
-        let disk_rows = sliced_vec.iter().map(|row| {
-            Row::new(
-                row.iter()
-                    .zip(widths)
-                    .map(|(cell, width)| truncate_text(cell, (*width).into())),
-            )
-        });
-
-        let title = self.generate_title(
-            draw_loc,
-            state.current_scroll_position.saturating_add(1),
-            table_data.data.len(),
-        );
-
-        let disk_block = if self.draw_border {
             Block::default()
                 .title(title)
                 .borders(Borders::ALL)
@@ -177,34 +128,99 @@ impl<'a> TextTable<'a> {
             Block::default().borders(Borders::NONE)
         };
 
-        let margined_draw_loc = Layout::default()
-            .constraints([Constraint::Percentage(100)])
-            .horizontal_margin(if self.is_on_widget || self.draw_border {
+        let (inner_width, inner_height) = {
+            let inner = disk_block.inner(margined_draw_loc);
+            (inner.width, inner.height)
+        };
+
+        if inner_width == 0 || inner_height == 0 {
+            f.render_widget(disk_block, margined_draw_loc);
+            margined_draw_loc
+        } else {
+            let show_header = inner_height > 1;
+            let header_height = if show_header { 1 } else { 0 };
+            let table_gap = if !show_header || draw_loc.height < TABLE_GAP_HEIGHT_LIMIT {
                 0
             } else {
-                1
-            })
-            .direction(Direction::Horizontal)
-            .split(draw_loc)[0];
+                self.table_gap
+            };
+
+            let sliced_vec = {
+                let num_rows = usize::from(inner_height.saturating_sub(table_gap + header_height));
+                let start = get_start_position(
+                    num_rows,
+                    &state.scroll_direction,
+                    &mut state.scroll_bar,
+                    state.current_scroll_position,
+                    self.is_force_redraw,
+                );
+                let end = min(table_data.data.len(), start + num_rows + 1);
+                state
+                    .table_state
+                    .select(Some(state.current_scroll_position.saturating_sub(start)));
+                &table_data.data[start..end]
+            };
 
-        // Draw!
-        f.render_stateful_widget(
-            Table::new(disk_rows)
-                .block(disk_block)
-                .header(header)
-                .highlight_style(self.highlighted_text_style)
-                .style(self.text_style)
-                .widths(
+            // Calculate widths
+            if self.recalculate_column_widths {
+                state
+                    .columns
+                    .iter_mut()
+                    .zip(&table_data.row_widths)
+                    .for_each(|(column, data_width)| match &mut column.width_bounds {
+                        app::WidthBounds::Soft {
+                            min_width: _,
+                            desired,
+                            max_percentage: _,
+                        } => {
+                            *desired = std::cmp::max(column.name.len(), *data_width) as u16;
+                        }
+                        app::WidthBounds::Hard(_width) => {}
+                    });
+
+                state.calculate_column_widths(inner_width, self.left_to_right);
+            }
+
+            let columns = &state.columns;
+            let widths = &state.calculated_widths;
+            // TODO: Maybe truncate this too?
+            let header = Row::new(columns.iter().map(|c| Text::raw(c.name.as_ref())))
+                .style(self.header_style)
+                .bottom_margin(table_gap);
+            let disk_rows = sliced_vec.iter().map(|row| {
+                Row::new(
+                    row.iter()
+                        .zip(widths)
+                        .map(|(cell, width)| truncate_text(cell, (*width).into())),
+                )
+            });
+
+            let widget = {
+                let mut table = Table::new(disk_rows)
+                    .block(disk_block)
+                    .highlight_style(self.highlighted_text_style)
+                    .style(self.text_style);
+
+                if show_header {
+                    table = table.header(header);
+                }
+
+                table
+            };
+
+            f.render_stateful_widget(
+                widget.widths(
                     &(widths
                         .iter()
                         .map(|w| Constraint::Length(*w))
                         .collect::<Vec<_>>()),
                 ),
-            margined_draw_loc,
-            &mut state.table_state,
-        );
+                margined_draw_loc,
+                &mut state.table_state,
+            );
 
-        margined_draw_loc
+            margined_draw_loc
+        }
     }
 }
 
diff --git a/src/canvas/widgets/cpu_graph.rs b/src/canvas/widgets/cpu_graph.rs
index fcb7daa2..36ba33e8 100644
--- a/src/canvas/widgets/cpu_graph.rs
+++ b/src/canvas/widgets/cpu_graph.rs
@@ -1,7 +1,7 @@
 use std::borrow::Cow;
 
 use crate::{
-    app::{layout_manager::WidgetDirection, App},
+    app::{layout_manager::WidgetDirection, App, CpuWidgetState},
     canvas::{
         components::{GraphData, TimeGraph},
         drawing_utils::{get_column_widths, get_start_position, should_hide_x_label},
@@ -115,6 +115,56 @@ impl Painter {
         }
     }
 
+    fn generate_points<'a>(
+        &self, cpu_widget_state: &CpuWidgetState, cpu_data: &'a [ConvertedCpuData],
+        show_avg_cpu: bool,
+    ) -> Vec<GraphData<'a>> {
+        let show_avg_offset = if show_avg_cpu { AVG_POSITION } else { 0 };
+
+        let current_scroll_position = cpu_widget_state.scroll_state.current_scroll_position;
+        if current_scroll_position == ALL_POSITION {
+            // This case ensures the other cases cannot have the position be equal to 0.
+            cpu_data
+                .iter()
+                .enumerate()
+                .rev()
+                .map(|(itx, cpu)| {
+                    let style = if show_avg_cpu && itx == AVG_POSITION {
+                        self.colours.avg_colour_style
+                    } else if itx == ALL_POSITION {
+                        self.colours.all_colour_style
+                    } else {
+                        let offset_position = itx - 1; // Because of the all position
+                        self.colours.cpu_colour_styles[(offset_position - show_avg_offset)
+                            % self.colours.cpu_colour_styles.len()]
+                    };
+
+                    GraphData {
+                        points: &cpu.cpu_data[..],
+                        style,
+                        name: None,
+                    }
+                })
+                .collect::<Vec<_>>()
+        } else if let Some(cpu) = cpu_data.get(current_scroll_position) {
+            let style = if show_avg_cpu && current_scroll_position == AVG_POSITION {
+                self.colours.avg_colour_style
+            } else {
+                let offset_position = current_scroll_position - 1; // Because of the all position
+                self.colours.cpu_colour_styles
+                    [(offset_position - show_avg_offset) % self.colours.cpu_colour_styles.len()]
+            };
+
+            vec![GraphData {
+                points: &cpu.cpu_data[..],
+                style,
+                name: None,
+            }]
+        } else {
+            vec![]
+        }
+    }
+
     fn draw_cpu_graph<B: Backend>(
         &self, f: &mut Frame<'_, B>, app_state: &mut App, draw_loc: Rect, widget_id: u64,
     ) {
@@ -131,52 +181,12 @@ impl Painter {
                 &mut cpu_widget_state.autohide_timer,
                 draw_loc,
             );
-            let show_avg_cpu = app_state.app_config_fields.show_average_cpu;
-            let show_avg_offset = if show_avg_cpu { AVG_POSITION } else { 0 };
-            let points = {
-                let current_scroll_position = cpu_widget_state.scroll_state.current_scroll_position;
-                if current_scroll_position == ALL_POSITION {
-                    // This case ensures the other cases cannot have the position be equal to 0.
-                    cpu_data
-                        .iter()
-                        .enumerate()
-                        .rev()
-                        .map(|(itx, cpu)| {
-                            let style = if show_avg_cpu && itx == AVG_POSITION {
-                                self.colours.avg_colour_style
-                            } else if itx == ALL_POSITION {
-                                self.colours.all_colour_style
-                            } else {
-                                let offset_position = itx - 1; // Because of the all position
-                                self.colours.cpu_colour_styles[(offset_position - show_avg_offset)
-                                    % self.colours.cpu_colour_styles.len()]
-                            };
-
-                            GraphData {
-                                points: &cpu.cpu_data[..],
-                                style,
-                                name: None,
-                            }
-                        })
-                        .collect::<Vec<_>>()
-                } else if let Some(cpu) = cpu_data.get(current_scroll_position) {
-                    let style = if show_avg_cpu && current_scroll_position == AVG_POSITION {
-                        self.colours.avg_colour_style
-                    } else {
-                        let offset_position = current_scroll_position - 1; // Because of the all position
-                        self.colours.cpu_colour_styles[(offset_position - show_avg_offset)
-                            % self.colours.cpu_colour_styles.len()]
-                    };
 
-                    vec![GraphData {
-                        points: &cpu.cpu_data[..],
-                        style,
-                        name: None,
-                    }]
-                } else {
-                    vec![]
-                }
-            };
+            let points = self.generate_points(
+                &cpu_widget_state,
+                cpu_data,
+                app_state.app_config_fields.show_average_cpu,
+            );
 
             // TODO: Maybe hide load avg if too long? Or maybe the CPU part.
             let title = if cfg!(target_family = "unix") {
diff --git a/src/canvas/widgets/disk_table.rs b/src/canvas/widgets/disk_table.rs
index e897a770..fd667290 100644
--- a/src/canvas/widgets/disk_table.rs
+++ b/src/canvas/widgets/disk_table.rs
@@ -24,7 +24,6 @@ impl Painter {
             };
             let margined_draw_loc = TextTable {
                 table_gap: app_state.app_config_fields.table_gap,
-                table_height_offset: self.table_height_offset,
                 is_force_redraw: app_state.is_force_redraw,
                 recalculate_column_widths,
                 header_style: self.colours.table_header_style,
diff --git a/src/canvas/widgets/temp_table.rs b/src/canvas/widgets/temp_table.rs
index 890411e2..bdd30134 100644
--- a/src/canvas/widgets/temp_table.rs
+++ b/src/canvas/widgets/temp_table.rs
@@ -24,7 +24,6 @@ impl Painter {
             };
             let margined_draw_loc = TextTable {
                 table_gap: app_state.app_config_fields.table_gap,
-                table_height_offset: self.table_height_offset,
                 is_force_redraw: app_state.is_force_redraw,
                 recalculate_column_widths,
                 header_style: self.colours.table_header_style,