feat: show list of patches that already have been Reviewed-by

In the last commit, we updated the UI to reflect the new functionality
of replying to a subset of patches from a series w/ the "Reviewed-by"
tag.

Make the line "Reviewed-by:" in the "Details" tab, display information
not only about the staged patches, but the ones recorded as already
replied with the tag, differentiating them by the color and the
appended `*`.

Following the example of the last commit, if a patches 1, 2, and 7 are
staged, and 0, 3, and 10 have already been replied with the tag, the
line will display as

```
Reviewed-by: (0, 1*, 2*, 3, 7*, 10)
```

Closes: #78

Signed-off-by: David Tadokoro <[email protected]>

src/ui/details_actions.rs

@@ -1,38 +1,91 @@
+use std::cmp::Ordering;
+
 use ratatui::{
     layout::{Constraint, Direction, Layout, Rect},
     style::{Color, Modifier, Style},
-    text::{Line, Span},
+    text::{Line, Span, ToSpan},
     widgets::{Block, Borders, Padding, Paragraph, Wrap},
     Frame,
 };
 
 use crate::app::{screens::details_actions::PatchsetAction, App};
 
-fn render_details_and_actions(f: &mut Frame, app: &App, details_chunk: Rect, actions_chunk: Rect) {
+/// Get list of indexes representing the patches that were replied w/ the
+/// "Reviewed-by:" tag, or that are staged to.
+///
+/// # Arguments
+///
+/// * `app`: Immutable reference to `patch-hub` model
+///
+/// # Returns
+///
+/// An owned `Vec<Span>` that is an ordered comma-separated list of the indexes.
+/// Staged indexes are appended w/ `*` and colored `Color::DarkGrey`. If there
+/// are no patches that were neither replied or staged w/ the tag, the return
+/// string will be empty.  
+fn reviewed_by_list(app: &App) -> Vec<Span> {
     let patchset_details_and_actions = app.patchset_details_and_actions_state.as_ref().unwrap();
 
-    let mut patches_to_reply = String::new();
+    let number_offset = if patchset_details_and_actions.has_cover_letter {
+        0
+    } else {
+        1
+    };
+
+    let mut replied_inds: Vec<usize> = Vec::new();
+    if let Some(already_reviewed_by) = app.reviewed_patchsets.get(
+        &patchset_details_and_actions
+            .representative_patch
+            .message_id()
+            .href,
+    ) {
+        replied_inds = already_reviewed_by
+            .iter()
+            .cloned()
+            .map(|i| i + number_offset)
+            .collect();
+        replied_inds.sort_unstable();
+    }
+
+    let mut staged_inds: Vec<usize> = Vec::new();
     if let Some(true) = patchset_details_and_actions
         .patchset_actions
         .get(&PatchsetAction::ReplyWithReviewedBy)
     {
-        patches_to_reply.push('(');
-        let number_offset = if patchset_details_and_actions.has_cover_letter {
-            0
-        } else {
-            1
-        };
-        let patches_to_reply_numbers: Vec<usize> = patchset_details_and_actions
+        staged_inds = patchset_details_and_actions
             .patches_to_reply
             .iter()
             .enumerate()
             .filter_map(|(i, &val)| if val { Some(i + number_offset) } else { None })
             .collect();
-        for number in patches_to_reply_numbers {
-            patches_to_reply.push_str(&format!("{number},"));
+        staged_inds.sort_unstable();
+    }
+
+    let reviewed_by_inds = merge_reviewed_by_inds(replied_inds, staged_inds);
+
+    let mut reviewed_by_list = Vec::new();
+    // let mut reviewed_by_list = String::new();
+
+    for (index, is_replied) in reviewed_by_inds {
+        let mut entry = index.to_string();
+        let mut entry_color = Style::default().fg(Color::White);
+        if !is_replied {
+            entry.push('*');
+            entry_color = entry_color.fg(Color::DarkGray);
         }
-        patches_to_reply = format!("{})", &patches_to_reply[..patches_to_reply.len() - 1]);
+        reviewed_by_list.push(Span::styled(entry, entry_color));
+        reviewed_by_list.push(Span::styled(
+            ", ".to_string(),
+            Style::default().fg(Color::White),
+        ));
     }
+    reviewed_by_list.pop();
+
+    reviewed_by_list
+}
+
+fn render_details_and_actions(f: &mut Frame, app: &App, details_chunk: Rect, actions_chunk: Rect) {
+    let patchset_details_and_actions = app.patchset_details_and_actions_state.as_ref().unwrap();
 
     let patchset_details = &patchset_details_and_actions.representative_patch;
     let mut patchset_details = vec![
@@ -72,11 +125,15 @@ fn render_details_and_actions(f: &mut Frame, app: &App, details_chunk: Rect, act
             ),
         ]),
     ];
-    if !patches_to_reply.is_empty() {
-        patchset_details.push(Line::from(vec![
-            Span::styled("Reviewed-by*: ", Style::default().fg(Color::Cyan)),
-            Span::styled(patches_to_reply, Style::default().fg(Color::DarkGray)),
-        ]));
+    let mut reviewed_by = reviewed_by_list(app);
+    if !reviewed_by.is_empty() {
+        let mut reviewed_by_line = vec![
+            Span::styled("Reviewed-by: ", Style::default().fg(Color::Cyan)),
+            '('.to_span(),
+        ];
+        reviewed_by_line.append(&mut reviewed_by);
+        reviewed_by_line.push(')'.to_span());
+        patchset_details.push(Line::from(reviewed_by_line));
     }
 
     let patchset_details = Paragraph::new(patchset_details)
@@ -224,3 +281,143 @@ pub fn keys_hint() -> Span<'static> {
         Style::default().fg(Color::Red),
     )
 }
+
+/// Receives two `usize` slices representing the patch indexes tagged w/
+/// "Reviewed-by", preceding those that were replied over those that are only
+/// staged.
+///
+/// # Arguments
+///
+/// * `replied_inds`: Ordered slice of patch indexes that were replied
+/// * `staged_inds`: Ordered slice of patch indexes that staged to be replied
+///
+/// # Returns
+///
+/// This function always returns a `Vec<(usize, bool)>` (empty or not). The
+/// tuples `(index, is_replied)` encode the precedence, in which `is_replied ==
+/// true` means that patch of number `index` was replied w/ the tag.
+fn merge_reviewed_by_inds(
+    mut replied_inds: Vec<usize>,
+    mut staged_inds: Vec<usize>,
+) -> Vec<(usize, bool)> {
+    let mut reviewed_by_inds = Vec::new();
+    let mut i = 0;
+    let mut j = 0;
+
+    // Don't assume the caller ordered the vectors beforehand
+    replied_inds.sort();
+    staged_inds.sort();
+
+    while (i != replied_inds.len()) && (j != staged_inds.len()) {
+        match replied_inds[i].cmp(&staged_inds[j]) {
+            Ordering::Less => {
+                reviewed_by_inds.push((replied_inds[i], true));
+                i += 1;
+            }
+            Ordering::Equal => {
+                reviewed_by_inds.push((replied_inds[i], true));
+                i += 1;
+                j += 1;
+            }
+            Ordering::Greater => {
+                reviewed_by_inds.push((staged_inds[j], false));
+                j += 1;
+            }
+        }
+    }
+
+    let mut remaining_inds: Vec<(usize, bool)>;
+    if i != replied_inds.len() {
+        remaining_inds = replied_inds[i..]
+            .iter()
+            .map(|&index| (index, true))
+            .collect();
+    } else {
+        remaining_inds = staged_inds[j..]
+            .iter()
+            .map(|&index| (index, false))
+            .collect();
+    }
+    reviewed_by_inds.append(&mut remaining_inds);
+
+    reviewed_by_inds
+}
+
+#[cfg(test)]
+mod tests {
+    use super::merge_reviewed_by_inds;
+
+    #[test]
+    fn test_merge_reviewed_by_inds() {
+        let replied_inds = vec![];
+        let staged_inds = vec![];
+        let reviewed_by_inds = merge_reviewed_by_inds(replied_inds, staged_inds);
+        assert_eq!(
+            reviewed_by_inds.len(),
+            0,
+            "No replied neither staged patches should result in empty reviewed-by"
+        );
+
+        let replied_inds = vec![0, 1, 2, 3, 4];
+        let staged_inds = vec![];
+        let reviewed_by_inds = merge_reviewed_by_inds(replied_inds.clone(), staged_inds);
+        assert_eq!(
+            reviewed_by_inds.len(),
+            5,
+            "No staged patches should result in reviewed-by w/ same size as replied"
+        );
+        assert_eq!(
+            reviewed_by_inds
+                .clone()
+                .into_iter()
+                .map(|(i, _)| i)
+                .collect::<Vec<usize>>(),
+            replied_inds,
+            "No staged patches should result in reviewed-by equal to replied"
+        );
+        assert!(
+            reviewed_by_inds.iter().all(|(_, b)| *b),
+            "No staged patches should result in reviewed-by equal to replied"
+        );
+
+        let replied_inds = vec![];
+        let staged_inds = vec![1, 3, 10];
+        let reviewed_by_inds = merge_reviewed_by_inds(replied_inds, staged_inds.clone());
+        assert_eq!(
+            reviewed_by_inds.len(),
+            3,
+            "No staged patches should result in reviewed-by w/ same size as staged"
+        );
+        assert_eq!(
+            reviewed_by_inds
+                .clone()
+                .into_iter()
+                .map(|(i, _)| i)
+                .collect::<Vec<usize>>(),
+            staged_inds,
+            "No staged patches should result in reviewed-by equal to staged"
+        );
+        assert!(
+            reviewed_by_inds.iter().all(|(_, b)| !*b),
+            "No staged patches should result in reviewed-by equal to staged"
+        );
+
+        let replied_inds = vec![0, 1, 2, 3, 4];
+        let staged_inds = vec![1, 3, 10];
+        let expected_reviewed_by_inds = vec![
+            (0, true),
+            (1, true),
+            (2, true),
+            (3, true),
+            (4, true),
+            (10, false),
+        ];
+        let reviewed_by_inds = merge_reviewed_by_inds(replied_inds, staged_inds);
+        assert_eq!(
+            reviewed_by_inds.len(),
+            6,
+            "No staged patches should result in reviewed-by w/ same size as staged"
+        );
+        assert_eq!(reviewed_by_inds, expected_reviewed_by_inds,);
+    }
+}