From f4676eb2c3897218e6a73778709d3d33fab946e2 Mon Sep 17 00:00:00 2001
From: quak <jonas.s97@gmx.ch>
Date: Mon, 27 Jan 2025 23:57:48 +0100
Subject: [PATCH] implemented `push` to stack entry by number

---
 src/arguments.rs |  2 +-
 src/main.rs      | 34 ++++++++++++++++++++++++----------
 src/stack.rs     | 15 +++++++--------
 todo.md          |  2 +-
 4 files changed, 33 insertions(+), 20 deletions(-)

diff --git a/src/arguments.rs b/src/arguments.rs
index bda53e6..57de548 100644
--- a/src/arguments.rs
+++ b/src/arguments.rs
@@ -39,7 +39,7 @@ pub struct PushArgs {
     pub show_stack: Option<bool>,
 
     /// change to <path>
-    pub path: Option<PathBuf>,
+    pub path: Option<String>,
 }
 
 #[derive(Debug, Clone, Args)]
diff --git a/src/main.rs b/src/main.rs
index 430632c..cf3be23 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -11,10 +11,12 @@ use clap::Parser;
 use config::*;
 use bookmarks::*;
 use config_parser::*;
+use dirs::home_dir;
 use output::Output;
 use stack::Stack;
 use util::to_rooted;
-use std::env::{current_dir, var};
+use std::char;
+use std::env::current_dir;
 use std::io::{Error, Result};
 use std::path::{Path, PathBuf};
 use std::str::FromStr;
@@ -72,17 +74,29 @@ fn main() -> Result<()> {
 }
 
 fn handle_push(args: &PushArgs, config: &Config, stack: &mut Stack, output: &mut Output) -> Result<()> {
-    let path = match args.path.clone() {
+    const PREFIX: char = '=';
+    let mut path_string = match args.path.clone() {
         Some(value) => value,
         None => {
-            let home_dir = match var("HOME") {
-                Ok(value) => value,
-                Err(error) => return Err(Error::other(error.to_string())),
-            };
-            match PathBuf::from_str(&home_dir) {
-                Ok(value) => value,
-                Err(error) => return Err(Error::other(error.to_string())),
-            }
+            String::new()
+        }
+    };
+    let path: PathBuf = if path_string.is_empty() {
+        match home_dir() {
+            Some(value) => value,
+            None => return Err(Error::other("-- failed to determine home directory")),
+        }
+    } else if path_string.starts_with(PREFIX) {
+        path_string = path_string.trim_start_matches(PREFIX).to_string();
+        let number: usize = match path_string.parse() {
+            Ok(value) => value,
+            Err(_) => return Err(Error::other("-- push : failed to convert path argument to number")),
+        };
+        stack.get_entry_by_number(number)?.to_path_buf()
+    } else {
+        match PathBuf::from_str(&path_string) {
+            Ok(value) => value,
+            Err(_) => return Err(Error::other("-- failed to create PathBuf from argument")),
         }
     };
     push_path(&path, stack, config, output)?;
diff --git a/src/stack.rs b/src/stack.rs
index ac1b8d1..4fff69a 100644
--- a/src/stack.rs
+++ b/src/stack.rs
@@ -1,6 +1,6 @@
 #![allow(dead_code)]
 
-use std::fs;
+use std::{fs, usize};
 use std::fs::File;
 use std::io::{Error, Result};
 use std::path::{Path, PathBuf};
@@ -112,13 +112,12 @@ impl Stack {
     /// return nth last entry
     pub fn get_entry_by_number(&mut self, entry_number: usize) -> Result<&PathBuf> {
         // index from the end of the vector as new entries are appended at the end of the list
-        let index = match self.stack.len().checked_sub(entry_number) {
-            Some(value) => value,
-            None => return Err(Error::other("-- no entry found at request index")),
-        };
-        match self.stack.get(index) {
-            Some(item) => Ok(item),
-            None => Err(Error::other("-- failed to retrieve stack entry by number")),
+        if entry_number >= self.stack.len() {
+            return Err(Error::other(format!("-- requested item ({entry_number}) out of bounds (stack.len() = {})", self.stack.len())));
+        }
+        match self.stack.iter().rev().nth(entry_number) {
+            Some(value) => Ok(value),
+            None => return Err(Error::other("-- failed to retrieve stack element #{entry_number}")),
         }
     }
 
diff --git a/todo.md b/todo.md
index db1c0fd..13e64f9 100644
--- a/todo.md
+++ b/todo.md
@@ -15,7 +15,7 @@
   - [x] color option for punctuation (mostly '/')
 - [x] bookmarks
   - [x] do not resolve links in bookmarks
-- [ ] push <number> to push path in stack
+- [x] push <number> to push path in stack
 - [x] write documentation
 - [x] change config file extension to `.toml`
 - [x] add bash completions