Add a special notation to jump to a random page

doc/NAVIGATION.md

@@ -45,3 +45,9 @@ Page names can also be used instead of page numbers:
 ```
 
 For the page names to be resolved, you'll need to name the first page of each category.
+
+## Special Notations
+
+`-` or `+` can be prepended to a page number to jump to a relative page.
+
+You can jump to a random page by specifying `_` as the page number.

src/view/home/mod.rs

@@ -14,6 +14,7 @@ use std::path::{Path, PathBuf};
 use std::process::{Command, Child, Stdio};
 use std::collections::HashMap;
 use std::io::{BufRead, BufReader};
+use rand::Rng;
 use regex::Regex;
 use serde_json::Value as JsonValue;
 use anyhow::{Error, format_err};
@@ -1313,7 +1314,11 @@ impl View for Home {
  true
  },
  Event::Submit(ViewId::GoToPageInput, ref text) => {
- if let Ok(index) = text.parse::<usize>() {
+ if text == "_" {
+ let mut rng = rand::thread_rng();
+ let index = rng.gen::<usize>() % self.pages_count;
+ self.go_to_page(index, hub, context);
+ } else if let Ok(index) = text.parse::<usize>() {
  self.go_to_page(index.saturating_sub(1), hub, context);
  }
  true

src/view/reader/mod.rs

@@ -15,6 +15,7 @@ use chrono::Local;
 use regex::Regex;
 use septem::prelude::*;
 use septem::{Roman, Digit};
+use rand::Rng;
 use crate::input::{DeviceEvent, FingerStatus, ButtonCode, ButtonStatus};
 use crate::framebuffer::{Framebuffer, UpdateMode, Pixmap};
 use crate::view::{View, Event, AppCmd, Hub, Bus, ViewId, EntryKind, EntryId, SliderId};
@@ -2953,7 +2954,11 @@ impl View for Reader {
  self.go_to_page(location, true, hub, context);
  }
  } else {
- if let Ok(number) = caps[2].parse::<f64>() {
+ if text == "_" {
+ let mut rng = rand::thread_rng();
+ let location = rng.gen::<usize>() % self.pages_count;
+ self.go_to_page(location, true, hub, context);
+ } else if let Ok(number) = caps[2].parse::<f64>() {
  let location = if !self.synthetic {
  let mut index = number.max(0.0) as usize;
  match prefix {