adding important subcommands

CLAUDE.md

@@ -0,0 +1,41 @@
+# CLAUDE.md
+
+This file provides guidance to Claude Code (claude.ai/code) when working with code in this repository.
+
+## Commands
+
+```sh
+cargo build          # build the project
+cargo run -- <cmd>   # run a subcommand (e.g. cargo run -- init)
+cargo test           # run all tests
+cargo test <name>    # run a single test by name
+cargo clippy         # lint
+```
+
+## What This Project Is
+
+`tour` is a CLI tool for creating and navigating code tutorials as a series of snapshots. Authors create tours by committing file snapshots with explanations; readers step through them with `next`/`prev`.
+
+**Author workflow:** `tour init` → `tour commit <files> -m <msg>` (repeat) → `tour end -m <msg>`
+
+**Reader workflow:** `tour start` → `tour next [n]` / `tour prev [n]`
+
+## Architecture
+
+Entry point is `main.rs`, which uses clap's derive macro to parse subcommands and dispatch to per-command modules.
+
+**On-disk format** (stored in `.tour/` in the project being toured):
+- `.tour/steps/<N>/` — one numbered directory per step
+- `.tour/session` — tracks current reader position as `STEP=<n>`
+
+**Module layout:**
+- `init.rs` — creates `.tour/steps/` and `.tour/session`
+- `commit.rs` — validates files, then saves them as a new numbered step
+- `end.rs` — finalizes the tour
+- `next.rs` / `prev.rs` — advance/retreat the session step
+- `utils.rs` — shared helpers: `copy_files`, `get_session_step`, `get_tour_step`, path validation
+- `error.rs` — custom error types (currently `CommitError`)
+
+Constants `TOUR_DIR` and `SESSION_PATH` are defined in `main.rs` and imported via `crate::`.
+
+**Status:** Early development. `next`, `prev`, and `end` are stubbed. `commit` validates paths but hasn't yet written the step to disk. `utils::get_tour_step` has a dead `Ok(0)` after a `match` expression (unreachable code).

src/commit.rs

@@ -1,24 +1,37 @@
+use crate::error::CommitError;
+use crate::utils::{copy_path, is_descendant_of_current_dir, is_file_in_dir};
 use crate::TOUR_DIR;
 use std::fs;
-use std::io::Write;
-use std::path::PathBuf;
+use std::path::{Path, PathBuf};
 
-pub fn commit(files: Vec<PathBuf>, message: String) -> Result<(), std::io::Error> {
-    // let files = files.iter().map(|p| p.as_ref()).collect();
-    //
-    // let dir = std::fs::read_dir(format!("{}/steps", TOUR_DIR))?;
-    //
-    // // USE /steps to find number of next step
-    // // let step_number =
-    //
-    // fs::create_dir_all(format!("{}/{}", TOUR_DIR, "steps/0/files"))?;
-    //
-    // // Copy files listed by command to step 0
-    // let dest = format!("{}/steps/0/files/", TOUR_DIR);
-    // crate::utils::copy_files(files, dest.as_ref())?;
-    //
-    // // Copy message
-    // let mut message_file = fs::File::create(format!("{}/steps/{}/message", TOUR_DIR, step_number))?;
-    // write!(message_file, "{}", message)?;
+pub fn commit(files: Vec<PathBuf>, message: String) -> Result<(), CommitError> {
+    let tour_dir = Path::new(TOUR_DIR);
+
+    for file in &files {
+        if !is_descendant_of_current_dir(file)? {
+            return Err(CommitError::NotADescendantOfCurrentDir(file.clone()));
+        }
+        if is_file_in_dir(file, tour_dir)? {
+            return Err(CommitError::InsideTourDir(file.clone()));
+        }
+    }
+
+    let steps_dir = tour_dir.join("steps");
+    let step_num = fs::read_dir(&steps_dir)?
+        .filter_map(|e| e.ok())
+        .filter(|e| e.path().is_dir())
+        .count();
+
+    let step_dir = steps_dir.join(step_num.to_string());
+    fs::create_dir_all(&step_dir)?;
+
+    for file in &files {
+        copy_path(file, &step_dir)?;
+    }
+
+    fs::write(step_dir.join("message"), &message)?;
+    crate::info::update_last_modified()?;
+
+    println!("Step {}: {}", step_num, message);
     Ok(())
 }

src/error.rs

@@ -0,0 +1,31 @@
+use std::io;
+use std::path::PathBuf;
+
+#[derive(Debug)]
+pub enum CommitError {
+    NotADescendantOfCurrentDir(PathBuf),
+    InsideTourDir(PathBuf),
+    Io(io::Error),
+}
+
+impl std::fmt::Display for CommitError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            Self::NotADescendantOfCurrentDir(path) => {
+                write!(f, "File {:?} is not a descendant of the working directory.", path)
+            }
+            Self::InsideTourDir(path) => {
+                write!(f, "File {:?} is inside a .tour directory, which is not allowed.", path)
+            }
+            Self::Io(e) => write!(f, "IO error: {}", e),
+        }
+    }
+}
+
+impl std::error::Error for CommitError {}
+
+impl From<io::Error> for CommitError {
+    fn from(e: io::Error) -> Self {
+        Self::Io(e)
+    }
+}

src/info.rs

@@ -0,0 +1,138 @@
+use std::fs;
+use std::io::{self, Write};
+use std::time::{SystemTime, UNIX_EPOCH};
+
+const INFO_PATH: &str = "./.tour/info";
+
+struct TourInfo {
+    author: String,
+    description: String,
+    language: String,
+    created: String,
+    updated: String,
+}
+
+impl TourInfo {
+    fn parse(content: &str) -> Self {
+        let mut author = String::new();
+        let mut description = String::new();
+        let mut language = String::new();
+        let mut created = String::new();
+        let mut updated = String::new();
+
+        for line in content.lines() {
+            if let Some((key, value)) = line.split_once('=') {
+                match key {
+                    "author" => author = value.to_string(),
+                    "description" => description = value.to_string(),
+                    "language" => language = value.to_string(),
+                    "created" => created = value.to_string(),
+                    "updated" => updated = value.to_string(),
+                    _ => {}
+                }
+            }
+        }
+
+        TourInfo { author, description, language, created, updated }
+    }
+
+    fn serialize(&self) -> String {
+        format!(
+            "author={}\ndescription={}\nlanguage={}\ncreated={}\nupdated={}\n",
+            self.author, self.description, self.language, self.created, self.updated
+        )
+    }
+}
+
+pub fn set_info() -> Result<(), io::Error> {
+    macro_rules! prompt {
+        ($msg:expr) => {{
+            print!($msg);
+            io::stdout().flush()?;
+            let mut buf = String::new();
+            io::stdin().read_line(&mut buf)?;
+            buf.trim().to_string()
+        }};
+    }
+
+    let author = prompt!("Author: ");
+    let description = prompt!("Description: ");
+    let language = prompt!("Language: ");
+    let today = current_date();
+
+    let info = TourInfo {
+        author,
+        description,
+        language,
+        created: today.clone(),
+        updated: today,
+    };
+
+    fs::write(INFO_PATH, info.serialize())
+}
+
+pub fn get_info() -> Result<(), io::Error> {
+    let content = fs::read_to_string(INFO_PATH).map_err(|_| {
+        io::Error::new(
+            io::ErrorKind::NotFound,
+            "No tour info found. Run `tour init` to set up a tour.",
+        )
+    })?;
+    let info = TourInfo::parse(&content);
+    println!("Author:      {}", info.author);
+    println!("Description: {}", info.description);
+    println!("Language:    {}", info.language);
+    println!("Created:     {}", info.created);
+    println!("Updated:     {}", info.updated);
+    Ok(())
+}
+
+pub fn update_last_modified() -> Result<(), io::Error> {
+    let content = fs::read_to_string(INFO_PATH).unwrap_or_default();
+    let mut info = TourInfo::parse(&content);
+    info.updated = current_date();
+    fs::write(INFO_PATH, info.serialize())
+}
+
+pub fn info() -> Result<(), io::Error> {
+    get_info()
+}
+
+fn current_date() -> String {
+    let secs = SystemTime::now()
+        .duration_since(UNIX_EPOCH)
+        .unwrap_or_default()
+        .as_secs();
+    let (y, m, d) = days_to_ymd((secs / 86400) as u32);
+    format!("{:04}-{:02}-{:02}", y, m, d)
+}
+
+fn days_to_ymd(mut days: u32) -> (u32, u32, u32) {
+    let mut year = 1970u32;
+    loop {
+        let days_in_year = if is_leap(year) { 366 } else { 365 };
+        if days < days_in_year {
+            break;
+        }
+        days -= days_in_year;
+        year += 1;
+    }
+    let month_days = if is_leap(year) {
+        [31u32, 29, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]
+    } else {
+        [31u32, 28, 31, 30, 31, 30, 31, 31, 30, 31, 30, 31]
+    };
+    let mut month = 1u32;
+    for (i, &md) in month_days.iter().enumerate() {
+        if days < md {
+            month = i as u32 + 1;
+            break;
+        }
+        days -= md;
+    }
+    (year, month, days + 1)
+}
+
+fn is_leap(year: u32) -> bool {
+    (year % 4 == 0 && year % 100 != 0) || year % 400 == 0
+}

src/init.rs

@@ -1,25 +1,20 @@
 // Create a .tour folder
-// Populate with tour/steps/0/message
-// Populate with tour/steps/0/files/file1
-// Populate with tour/steps/0/files/file2
+// Create directory ./.tour/steps that stores tutorial steps
+// Create file ./.tour/session that logs sessions information
 
 use crate::TOUR_DIR;
-use crate::utils::copy_files;
-
-use std::fs;
-use std::fs::File;
-use std::io::Write;
+use std::fs::DirBuilder;
 use std::path::PathBuf;
 
-pub fn init(files: Vec<PathBuf>, message: String) -> Result<(), std::io::Error> {
-    // // Convert PathBuf to &Path
-    // let files = files.iter().map(|p| p.as_path()).collect();
-    //
-    // // Check TOUR_DIR exists (it shouldn't because user calls init)
-    // if fs::exists(TOUR_DIR)? {
-    //     panic!("{} folder exists", TOUR_DIR);
-    // }
-    // // Create dir recursively
+// Creates the directory for tour
+pub fn init() -> Result<(), std::io::Error> {
+    let tour_dir = PathBuf::from(TOUR_DIR);
 
-    Ok(())
+    DirBuilder::new()
+        .recursive(true)
+        .create(tour_dir.join("steps"))?;
+
+    std::fs::File::create(tour_dir.join("session"))?;
+
+    crate::info::set_info()
 }

src/main.rs

@@ -4,13 +4,14 @@ use std::path::PathBuf;
 
 mod commit;
 mod end;
+mod error;
 mod init;
-mod next;
-mod prev;
+mod step;
 mod utils;
+mod info;
 
 const TOUR_DIR: &str = "./.tour";
-const DEFAULT_SESSION: &str = "./.tour/session";
+const SESSION_PATH: &str = "./.tour/session";
 
 #[derive(Parser)]
 #[command(author, version, about, long_about = None)]
@@ -22,12 +23,8 @@ struct Args {
 #[derive(Subcommand)]
 enum Commands {
     // Create a new tour
-    Init {
-        #[arg(value_name = "FILES")]
-        files: Vec<PathBuf>,
-        #[arg(short, value_name = "MESSAGE")]
-        message: String,
-    },
+    Init,
+
     // Add steps to the tour
     Commit {
         files: Vec<PathBuf>,
@@ -35,6 +32,7 @@ enum Commands {
         #[arg(short, long, value_name = "MESSAGE")]
         message: String,
     },
+
     // Finish the tour
     End {
         #[arg(short, long, value_name = "MESSAGE")]
@@ -46,21 +44,36 @@ enum Commands {
         #[arg(short, value_name = "NUM STEPS")]
         n: Option<i32>,
     },
+
     // Go to previous step of tour
     Prev {
         #[arg(short, value_name = "NUM STEPS")]
         n: Option<i32>,
     },
+
+    // Go to a specific step of tour
+    Step {
+        #[arg(value_name = "STEP")]
+        n: i32,
+    },
+
+    // Go to beginning of tour
+    Start,
+
+    Info,
 }
 
 fn main() -> Result<(), Box<dyn Error>> {
     let args = Args::parse();
     match args.command {
-        Some(Commands::Init { files, message }) => crate::init::init(files, message)?,
+        Some(Commands::Init) => crate::init::init()?,
         Some(Commands::Commit { files, message }) => crate::commit::commit(files, message)?,
         Some(Commands::End { message }) => crate::end::end(message)?,
-        Some(Commands::Next { n }) => crate::next::next(n)?,
-        Some(Commands::Prev { n }) => crate::prev::prev(n)?,
+        Some(Commands::Next { n }) => crate::step::next(n)?,
+        Some(Commands::Prev { n }) => crate::step::prev(n)?,
+        Some(Commands::Step { n }) => crate::step::step_n(n)?,
+        Some(Commands::Start) => crate::step::step_n(0)?,
+        Some(Commands::Info) => crate::info::info()?,
         _ => println!("command not found"),
     }
     Ok(())

src/next.rs

@@ -1,4 +0,0 @@
-pub fn next(n: Option<i32>) -> Result<(), std::io::Error> {
-    let n = n.unwrap_or(1);
-    Ok(())
-}

src/prev.rs

@@ -1,4 +0,0 @@
-pub fn prev(n: Option<i32>) -> Result<(), std::io::Error> {
-    let n = n.unwrap_or(1);
-    Ok(())
-}

src/step.rs

@@ -0,0 +1,237 @@
+use crate::utils::get_tour_step;
+use crate::SESSION_PATH;
+use crate::TOUR_DIR;
+use std::collections::BTreeMap;
+use std::fs;
+use std::io;
+use std::path::{Path, PathBuf};
+
+const RED: &str = "\x1b[31m";
+const GREEN: &str = "\x1b[32m";
+const CYAN: &str = "\x1b[36m";
+const BOLD: &str = "\x1b[1m";
+const RESET: &str = "\x1b[0m";
+
+pub fn step_n(n: i32) -> Result<(), io::Error> {
+    let total = get_tour_step()
+        .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e.to_string()))?;
+
+    if n < 0 || n >= total as i32 {
+        return Err(io::Error::new(
+            io::ErrorKind::InvalidInput,
+            format!("Step {} is out of range (0-{})", n, total - 1),
+        ));
+    }
+
+    step(n - current_step())
+}
+
+pub fn next(n: Option<i32>) -> Result<(), io::Error> {
+    step(n.unwrap_or(1))
+}
+
+pub fn prev(n: Option<i32>) -> Result<(), io::Error> {
+    step(-n.unwrap_or(1))
+}
+
+/// Returns the current step as a signed integer.
+/// Returns -1 when the session has no step yet (reader hasn't started).
+fn current_step() -> i32 {
+    fs::read_to_string(SESSION_PATH)
+        .ok()
+        .and_then(|s| {
+            s.split("STEP=")
+                .nth(1)
+                .and_then(|v| v.trim().parse::<i32>().ok())
+        })
+        .unwrap_or(-1)
+}
+
+fn step(delta: i32) -> Result<(), io::Error> {
+    let current = current_step();
+    let total = get_tour_step()
+        .map_err(|e| io::Error::new(io::ErrorKind::InvalidData, e.to_string()))?;
+
+    let new_step = current + delta;
+    if new_step < 0 || new_step >= total as i32 {
+        return Err(io::Error::new(
+            io::ErrorKind::InvalidInput,
+            format!("Step {} is out of range (0-{})", new_step, total - 1),
+        ));
+    }
+    let new_step = new_step as u32;
+
+    let cwd = std::env::current_dir()?;
+    let old_files = snapshot_files(&cwd)?;
+
+    // Clear CWD except .tour/
+    for entry in fs::read_dir(&cwd)? {
+        let entry = entry?;
+        if entry.file_name() == ".tour" {
+            continue;
+        }
+        let path = entry.path();
+        if path.is_dir() {
+            fs::remove_dir_all(&path)?;
+        } else {
+            fs::remove_file(&path)?;
+        }
+    }
+
+    // Copy step contents into CWD (skipping the message file)
+    let step_dir = Path::new(TOUR_DIR).join("steps").join(new_step.to_string());
+    for entry in fs::read_dir(&step_dir)? {
+        let entry = entry?;
+        if entry.file_name() == "message" {
+            continue;
+        }
+        copy_into(&entry.path(), &cwd.join(entry.file_name()))?;
+    }
+
+    // Persist the new step
+    fs::write(SESSION_PATH, format!("STEP={}", new_step))?;
+
+    let new_files = snapshot_files(&cwd)?;
+    print_changes(&old_files, &new_files);
+
+    let message = fs::read_to_string(step_dir.join("message")).unwrap_or_default();
+    println!("\n{BOLD}Step {new_step}/{total}:{RESET} {}", message.trim());
+
+    Ok(())
+}
+
+fn snapshot_files(root: &Path) -> Result<BTreeMap<PathBuf, String>, io::Error> {
+    let mut files = BTreeMap::new();
+    collect_files(root, root, &mut files)?;
+    Ok(files)
+}
+
+fn collect_files(
+    root: &Path,
+    dir: &Path,
+    files: &mut BTreeMap<PathBuf, String>,
+) -> Result<(), io::Error> {
+    for entry in fs::read_dir(dir)? {
+        let entry = entry?;
+        if entry.file_name() == ".tour" {
+            continue;
+        }
+        let path = entry.path();
+        if path.is_dir() {
+            collect_files(root, &path, files)?;
+        } else {
+            let relative = path.strip_prefix(root).unwrap_or(&path).to_path_buf();
+            let content = fs::read_to_string(&path).unwrap_or_default();
+            files.insert(relative, content);
+        }
+    }
+    Ok(())
+}
+
+fn print_changes(old: &BTreeMap<PathBuf, String>, new: &BTreeMap<PathBuf, String>) {
+    for (path, new_content) in new {
+        match old.get(path) {
+            None => println!("{GREEN}  new:      {}{RESET}", path.display()),
+            Some(old_content) if old_content != new_content => {
+                println!("{CYAN}  modified: {}{RESET}", path.display());
+                print_diff(old_content, new_content);
+            }
+            _ => {}
+        }
+    }
+    for path in old.keys() {
+        if !new.contains_key(path) {
+            println!("{RED}  deleted:  {}{RESET}", path.display());
+        }
+    }
+}
+
+fn print_diff(old: &str, new: &str) {
+    let old_lines: Vec<&str> = old.lines().collect();
+    let new_lines: Vec<&str> = new.lines().collect();
+
+    let m = old_lines.len();
+    let n = new_lines.len();
+
+    // LCS table
+    let mut dp = vec![vec![0usize; n + 1]; m + 1];
+    for i in 1..=m {
+        for j in 1..=n {
+            if old_lines[i - 1] == new_lines[j - 1] {
+                dp[i][j] = dp[i - 1][j - 1] + 1;
+            } else {
+                dp[i][j] = dp[i - 1][j].max(dp[i][j - 1]);
+            }
+        }
+    }
+
+    // Backtrack
+    let mut ops: Vec<(char, &str)> = Vec::new();
+    let (mut i, mut j) = (m, n);
+    while i > 0 || j > 0 {
+        if i > 0 && j > 0 && old_lines[i - 1] == new_lines[j - 1] {
+            ops.push((' ', old_lines[i - 1]));
+            i -= 1;
+            j -= 1;
+        } else if j > 0 && (i == 0 || dp[i][j - 1] >= dp[i - 1][j]) {
+            ops.push(('+', new_lines[j - 1]));
+            j -= 1;
+        } else {
+            ops.push(('-', old_lines[i - 1]));
+            i -= 1;
+        }
+    }
+    ops.reverse();
+
+    // Print with context: only show changed lines and up to 2 surrounding context lines
+    const CTX: usize = 2;
+    let changed: Vec<usize> = ops
+        .iter()
+        .enumerate()
+        .filter(|(_, (op, _))| *op != ' ')
+        .map(|(i, _)| i)
+        .collect();
+
+    if changed.is_empty() {
+        return;
+    }
+
+    let mut visible = vec![false; ops.len()];
+    for &ci in &changed {
+        let lo = ci.saturating_sub(CTX);
+        let hi = (ci + CTX + 1).min(ops.len());
+        for v in lo..hi {
+            visible[v] = true;
+        }
+    }
+
+    let mut prev_visible = false;
+    for (idx, (op, line)) in ops.iter().enumerate() {
+        if !visible[idx] {
+            if prev_visible {
+                println!("    ...");
+            }
+            prev_visible = false;
+            continue;
+        }
+        prev_visible = true;
+        match op {
+            '+' => println!("{GREEN}  + {line}{RESET}"),
+            '-' => println!("{RED}  - {line}{RESET}"),
+            _ => println!("    {line}"),
+        }
+    }
+}
+
+fn copy_into(src: &Path, dest: &Path) -> Result<(), io::Error> {
+    if src.is_dir() {
+        fs::create_dir_all(dest)?;
+        for entry in fs::read_dir(src)? {
+            let entry = entry?;
+            copy_into(&entry.path(), &dest.join(entry.file_name()))?;
+        }
+    } else {
+        fs::copy(src, dest)?;
+    }
+    Ok(())
+}

src/utils.rs

@@ -2,23 +2,62 @@ use std::fs;
 use std::io;
 use std::path::Path;
 
-pub fn copy_files(files: Vec<&Path>, dest_dir: &Path) -> Result<(), io::Error> {
-    for file in files {
-        // Get the relative path components
-        let dest_path = dest_dir.join(file);
+use crate::SESSION_PATH;
+use crate::TOUR_DIR;
 
-        // Create parent directories if they don't exist
-        if let Some(parent) = dest_path.parent() {
+/// Copies a file or directory into dest_dir, preserving relative path structure.
+/// e.g. `src/main.rs` → `dest_dir/src/main.rs`
+pub fn copy_path(src: &Path, dest_dir: &Path) -> Result<(), io::Error> {
+    let relative_src = if src.is_absolute() {
+        let cwd = std::env::current_dir()?;
+        src.strip_prefix(&cwd).unwrap_or(src).to_path_buf()
+    } else {
+        src.to_path_buf()
+    };
+
+    if src.is_dir() {
+        let dest = dest_dir.join(&relative_src);
+        fs::create_dir_all(&dest)?;
+        for entry in fs::read_dir(src)? {
+            let entry = entry?;
+            copy_path(&entry.path(), dest_dir)?;
+        }
+    } else {
+        let dest = dest_dir.join(&relative_src);
+        if let Some(parent) = dest.parent() {
             fs::create_dir_all(parent)?;
         }
-
-        // Copy the file
-        fs::copy(file, dest_path)?;
+        fs::copy(src, &dest)?;
     }
     Ok(())
 }
 
-pub fn session_step(session_file: &Path) -> Result<u32, Box<dyn std::error::Error>> {
-    // Read ./.tour/session to find what step user is currently looking at
-    Ok((0))
+pub fn is_descendant_of_current_dir(file: &Path) -> Result<bool, io::Error> {
+    is_file_in_dir(file, &std::env::current_dir()?)
+}
+
+pub fn is_file_in_dir(file: &Path, dir: &Path) -> Result<bool, io::Error> {
+    let file_canon = file.canonicalize()?;
+    let dir_canon = dir.canonicalize()?;
+    Ok(file_canon.starts_with(&dir_canon))
+}
+
+pub fn get_session_step() -> Result<u32, Box<dyn std::error::Error>> {
+    let session = fs::read_to_string(SESSION_PATH)?;
+    let step = session
+        .split("STEP=")
+        .nth(1)
+        .ok_or("no STEP in session")?
+        .trim()
+        .parse::<u32>()?;
+    Ok(step)
+}
+
+pub fn get_tour_step() -> Result<u32, Box<dyn std::error::Error>> {
+    let steps_dir = Path::new(TOUR_DIR).join("steps");
+    let count = fs::read_dir(&steps_dir)?
+        .filter_map(|e| e.ok())
+        .filter(|e| e.path().is_dir())
+        .count() as u32;
+    Ok(count)
 }