Replace scrolling methods with enum

The different scrolling methods added a bunch of boilerplate where the
call was just forwarded to the next struct, this has been removed by
making the scroll amount into a struct.

Now everything is called through one method and the parameter decides
how far the viewport should be scrolled.

4 files changed, 44 insertions, 80 deletions

diff --git a/src/event.rs b/src/event.rs
index 322f0278..4d50efda 100644
--- a/src/event.rs
+++ b/src/event.rs
@@ -10,6 +10,7 @@ use parking_lot::MutexGuard;
 use glutin::{self, ModifiersState, Event, ElementState};
 use copypasta::{Clipboard, Load, Store};
 
+use grid::Scroll;
 use config::{self, Config};
 use cli::Options;
 use display::OnResize;
@@ -53,24 +54,8 @@ impl<'a, N: Notify + 'a> input::ActionContext for ActionContext<'a, N> {
         *self.size_info
     }
 
-    fn scroll(&mut self, count: isize) {
-        self.terminal.scroll_display(count);
-    }
-
-    fn reset_scroll(&mut self) {
-        self.terminal.reset_scroll();
-    }
-
-    fn scroll_to_top(&mut self) {
-        self.terminal.scroll_to_top();
-    }
-
-    fn scroll_page_up(&mut self) {
-        self.terminal.scroll_page_up();
-    }
-
-    fn scroll_page_down(&mut self) {
-        self.terminal.scroll_page_down();
+    fn scroll(&mut self, scroll: Scroll) {
+        self.terminal.scroll_display(scroll);
     }
 
     fn copy_selection(&self, buffer: ::copypasta::Buffer) {
diff --git a/src/grid/mod.rs b/src/grid/mod.rs
index ac761adc..65bc8382 100644
--- a/src/grid/mod.rs
+++ b/src/grid/mod.rs
@@ -113,6 +113,14 @@ pub struct GridIterator<'a, T: 'a> {
     top: usize,
 }
 
+pub enum Scroll {
+    Lines(isize),
+    PageUp,
+    PageDown,
+    Top,
+    Bottom,
+}
+
 impl<T: Copy + Clone> Grid<T> {
     pub fn new(lines: index::Line, cols: index::Column, scrollback: usize, template: T) -> Grid<T> {
         let mut raw = Storage::with_capacity(*lines + scrollback, lines);
@@ -165,34 +173,28 @@ impl<T: Copy + Clone> Grid<T> {
         self.line_to_offset(line) + self.display_offset
     }
 
-    pub fn scroll_display(&mut self, count: isize) {
-        self.display_offset = min(
-                max((self.display_offset as isize) + count, 0isize) as usize,
-                self.scroll_limit
-            );
-    }
-
-    pub fn reset_scroll_display(&mut self) {
-        self.display_offset = 0;
-    }
-
-    pub fn scroll_to_top(&mut self) {
-        self.display_offset = self.scroll_limit;
-    }
-
-    pub fn scroll_page_up(&mut self) {
-        if self.display_offset + self.lines.0 >= self.scroll_limit {
-            self.display_offset = self.scroll_limit;
-        } else {
-            self.display_offset += self.lines.0;
-        }
-    }
-
-    pub fn scroll_page_down(&mut self) {
-        if self.display_offset <= self.lines.0 {
-            self.display_offset = 0;
-        } else {
-            self.display_offset -= self.lines.0;
+    pub fn scroll_display(&mut self, scroll: Scroll) {
+        match scroll {
+            Scroll::Lines(count) => {
+                self.display_offset = min(
+                    max((self.display_offset as isize) + count, 0isize) as usize,
+                    self.scroll_limit
+                );
+            },
+            Scroll::PageUp => {
+                self.display_offset = min(
+                    self.display_offset + self.lines.0,
+                    self.scroll_limit
+                );
+            },
+            Scroll::PageDown => {
+                self.display_offset -= min(
+                    self.display_offset,
+                    self.lines.0
+                );
+            },
+            Scroll::Top => self.display_offset = self.scroll_limit,
+            Scroll::Bottom => self.display_offset = 0,
         }
     }
 
diff --git a/src/input.rs b/src/input.rs
index 96c67db6..904f252a 100644
--- a/src/input.rs
+++ b/src/input.rs
@@ -28,6 +28,7 @@ use copypasta::{Clipboard, Load, Buffer};
 use glutin::{ElementState, VirtualKeyCode, MouseButton, TouchPhase, MouseScrollDelta, ModifiersState};
 
 use config;
+use grid::Scroll;
 use event::{ClickState, Mouse};
 use index::{Line, Column, Side, Point};
 use term::SizeInfo;
@@ -65,11 +66,7 @@ pub trait ActionContext {
     fn last_modifiers(&mut self) -> &mut ModifiersState;
     fn change_font_size(&mut self, delta: i8);
     fn reset_font_size(&mut self);
-    fn scroll(&mut self, count: isize);
-    fn reset_scroll(&mut self);
-    fn scroll_to_top(&mut self);
-    fn scroll_page_up(&mut self);
-    fn scroll_page_down(&mut self);
+    fn scroll(&mut self, scroll: Scroll);
 }
 
 /// Describes a state and action to take in that state
@@ -250,16 +247,16 @@ impl Action {
                ctx.reset_font_size();
             },
             Action::ScrollPageUp => {
-                ctx.scroll_page_up();
+                ctx.scroll(Scroll::PageUp);
             },
             Action::ScrollPageDown => {
-                ctx.scroll_page_down();
+                ctx.scroll(Scroll::PageDown);
             },
             Action::ScrollToTop => {
-                ctx.scroll_to_top();
+                ctx.scroll(Scroll::Top);
             },
             Action::ScrollToBottom => {
-                ctx.reset_scroll();
+                ctx.scroll(Scroll::Bottom);
             },
         }
     }
@@ -486,7 +483,7 @@ impl<'a, A: ActionContext + 'a> Processor<'a, A> {
             self.ctx.write_to_pty(content);
         } else {
             for _ in 0..scroll_multiplier {
-                self.ctx.scroll(-((code as isize) * 2 - 129));
+                self.ctx.scroll(Scroll::Lines(-((code as isize) * 2 - 129)));
             }
         }
     }
@@ -553,7 +550,7 @@ impl<'a, A: ActionContext + 'a> Processor<'a, A> {
     /// Process a received character
     pub fn received_char(&mut self, c: char) {
         if !*self.ctx.suppress_chars() {
-            self.ctx.reset_scroll();
+            self.ctx.scroll(Scroll::Bottom);
             self.ctx.clear_selection();
 
             let utf8_len = c.len_utf8();
diff --git a/src/term/mod.rs b/src/term/mod.rs
index 8f9fee1b..c97cd84d 100644
--- a/src/term/mod.rs
+++ b/src/term/mod.rs
@@ -24,7 +24,7 @@ use unicode_width::UnicodeWidthChar;
 
 use font::{self, Size};
 use ansi::{self, Color, NamedColor, Attr, Handler, CharsetIndex, StandardCharset, CursorStyle};
-use grid::{BidirectionalIterator, Grid, Indexed, IndexRegion, DisplayIter};
+use grid::{BidirectionalIterator, Grid, Indexed, IndexRegion, DisplayIter, Scroll};
 use index::{self, Point, Column, Line, IndexRange, Contains, RangeInclusive, Linear};
 use selection::{self, Selection, Locations};
 use config::{Config, VisualBellAnimation};
@@ -823,28 +823,8 @@ impl Term {
         self.next_title.take()
     }
 
-    pub fn scroll_display(&mut self, count: isize) {
-        self.grid.scroll_display(count);
-        self.dirty = true;
-    }
-
-    pub fn reset_scroll(&mut self) {
-        self.grid.reset_scroll_display();
-        self.dirty = true;
-    }
-
-    pub fn scroll_to_top(&mut self) {
-        self.grid.scroll_to_top();
-        self.dirty = true;
-    }
-
-    pub fn scroll_page_up(&mut self) {
-        self.grid.scroll_page_up();
-        self.dirty = true;
-    }
-
-    pub fn scroll_page_down(&mut self) {
-        self.grid.scroll_page_down();
+    pub fn scroll_display(&mut self, scroll: Scroll) {
+        self.grid.scroll_display(scroll);
         self.dirty = true;
     }