Implement resetting

4 files changed, 53 insertions, 33 deletions

diff --git a/src/exercise.rs b/src/exercise.rs
index d01d427..508f477 100644
--- a/src/exercise.rs
+++ b/src/exercise.rs
@@ -10,7 +10,7 @@ use winnow::ascii::{space0, Caseless};
 use winnow::combinator::opt;
 use winnow::Parser;
 
-use crate::embedded::EMBEDDED_FILES;
+use crate::embedded::{WriteStrategy, EMBEDDED_FILES};
 
 // The number of context lines above and below a highlighted line.
 const CONTEXT: usize = 2;
@@ -220,6 +220,12 @@ impl Exercise {
     pub fn looks_done(&self) -> Result<bool> {
         self.state().map(|state| state == State::Done)
     }
+
+    pub fn reset(&self) -> Result<()> {
+        EMBEDDED_FILES
+            .write_exercise_to_disk(&self.path, WriteStrategy::Overwrite)
+            .with_context(|| format!("Failed to reset the exercise {self}"))
+    }
 }
 
 impl Display for Exercise {
diff --git a/src/list.rs b/src/list.rs
index 4d26702..e2af21d 100644
--- a/src/list.rs
+++ b/src/list.rs
@@ -48,6 +48,12 @@ pub fn list(state_file: &mut StateFile, exercises: &[Exercise]) -> Result<()> {
             KeyCode::Up | KeyCode::Char('k') => ui_state.select_previous(),
             KeyCode::Home | KeyCode::Char('g') => ui_state.select_first(),
             KeyCode::End | KeyCode::Char('G') => ui_state.select_last(),
+            KeyCode::Char('r') => {
+                let selected = ui_state.selected();
+                exercises[selected].reset()?;
+                state_file.reset(selected)?;
+                ui_state.table = ui_state.table.rows(UiState::rows(state_file, exercises));
+            }
             KeyCode::Char('c') => {
                 state_file.set_next_exercise_ind(ui_state.selected())?;
                 ui_state.table = ui_state.table.rows(UiState::rows(state_file, exercises));
diff --git a/src/main.rs b/src/main.rs
index 3d691b0..81f6617 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -16,7 +16,6 @@ mod verify;
 mod watch;
 
 use crate::consts::WELCOME;
-use crate::embedded::{WriteStrategy, EMBEDDED_FILES};
 use crate::exercise::{Exercise, ExerciseList};
 use crate::run::run;
 use crate::verify::verify;
@@ -56,6 +55,26 @@ enum Subcommands {
     List,
 }
 
+fn find_exercise<'a>(name: &str, exercises: &'a [Exercise]) -> Result<(usize, &'a Exercise)> {
+    if name == "next" {
+        for (ind, exercise) in exercises.iter().enumerate() {
+            if !exercise.looks_done()? {
+                return Ok((ind, exercise));
+            }
+        }
+
+        println!("🎉 Congratulations! You have done all the exercises!");
+        println!("🔚 There are no more exercises to do next!");
+        exit(0);
+    }
+
+    exercises
+        .iter()
+        .enumerate()
+        .find(|(_, exercise)| exercise.name == name)
+        .with_context(|| format!("No exercise found for '{name}'!"))
+}
+
 fn main() -> Result<()> {
     let args = Args::parse();
 
@@ -86,30 +105,29 @@ If you are just starting with Rustlings, run the command `rustlings init` to ini
         exit(1);
     }
 
-    let mut state = StateFile::read_or_default(&exercises);
+    let mut state_file = StateFile::read_or_default(&exercises);
 
     match args.command {
         None | Some(Subcommands::Watch) => {
-            watch::watch(&state, &exercises)?;
+            watch::watch(&state_file, &exercises)?;
         }
         // `Init` is handled above.
         Some(Subcommands::Init) => (),
         Some(Subcommands::List) => {
-            list::list(&mut state, &exercises)?;
+            list::list(&mut state_file, &exercises)?;
         }
         Some(Subcommands::Run { name }) => {
-            let exercise = find_exercise(&name, &exercises)?;
+            let (_, exercise) = find_exercise(&name, &exercises)?;
             run(exercise).unwrap_or_else(|_| exit(1));
         }
         Some(Subcommands::Reset { name }) => {
-            let exercise = find_exercise(&name, &exercises)?;
-            EMBEDDED_FILES
-                .write_exercise_to_disk(&exercise.path, WriteStrategy::Overwrite)
-                .with_context(|| format!("Failed to reset the exercise {exercise}"))?;
+            let (ind, exercise) = find_exercise(&name, &exercises)?;
+            exercise.reset()?;
+            state_file.reset(ind)?;
             println!("The file {} has been reset!", exercise.path.display());
         }
         Some(Subcommands::Hint { name }) => {
-            let exercise = find_exercise(&name, &exercises)?;
+            let (_, exercise) = find_exercise(&name, &exercises)?;
             println!("{}", exercise.hint);
         }
         Some(Subcommands::Verify) => match verify(&exercises, 0)? {
@@ -120,22 +138,3 @@ If you are just starting with Rustlings, run the command `rustlings init` to ini
 
     Ok(())
 }
-
-fn find_exercise<'a>(name: &str, exercises: &'a [Exercise]) -> Result<&'a Exercise> {
-    if name == "next" {
-        for exercise in exercises {
-            if !exercise.looks_done()? {
-                return Ok(exercise);
-            }
-        }
-
-        println!("🎉 Congratulations! You have done all the exercises!");
-        println!("🔚 There are no more exercises to do next!");
-        exit(0);
-    }
-
-    exercises
-        .iter()
-        .find(|e| e.name == name)
-        .with_context(|| format!("No exercise found for '{name}'!"))
-}
diff --git a/src/state_file.rs b/src/state_file.rs
index ca7ed34..693c78d 100644
--- a/src/state_file.rs
+++ b/src/state_file.rs
@@ -10,9 +10,11 @@ pub struct StateFile {
     progress: Vec<bool>,
 }
 
+const BAD_INDEX_ERR: &str = "The next exercise index is higher than the number of exercises";
+
 impl StateFile {
     fn read(exercises: &[Exercise]) -> Option<Self> {
-        let file_content = fs::read(".rustlings.json").ok()?;
+        let file_content = fs::read(".rustlings-state.json").ok()?;
 
         let slf: Self = serde_json::de::from_slice(&file_content).ok()?;
 
@@ -34,6 +36,8 @@ impl StateFile {
         // TODO: Capacity
         let mut buf = Vec::with_capacity(1024);
         serde_json::ser::to_writer(&mut buf, self).context("Failed to serialize the state")?;
+        fs::write(".rustlings-state.json", buf)
+            .context("Failed to write the state file `.rustlings-state.json`")?;
 
         Ok(())
     }
@@ -45,9 +49,8 @@ impl StateFile {
 
     pub fn set_next_exercise_ind(&mut self, ind: usize) -> Result<()> {
         if ind >= self.progress.len() {
-            bail!("The next exercise index is higher than the number of exercises");
+            bail!(BAD_INDEX_ERR);
         }
-
         self.next_exercise_ind = ind;
         self.write()
     }
@@ -56,4 +59,10 @@ impl StateFile {
     pub fn progress(&self) -> &[bool] {
         &self.progress
     }
+
+    pub fn reset(&mut self, ind: usize) -> Result<()> {
+        let done = self.progress.get_mut(ind).context(BAD_INDEX_ERR)?;
+        *done = false;
+        self.write()
+    }
 }