Merge the landing branch into land-r8

# Conflicts:
#	contributors/people.toml
#	crates/engine/src/cmd/file.rs
#	crates/pptx/src/opc.rs
#	crates/pptx/tests/roundtrip.rs
#	crates/ui-egui/src/backstage.rs
#	crates/ui-egui/src/lib.rs

crates/model/src/bidi.rs

@@ -0,0 +1,81 @@
+//! Bidirectional text helpers (UAX #9).
+//!
+//! Follows Unicode Bidirectional Algorithm (UAX #9 rules P2 and P3) for paragraph
+//! base direction auto-detection.
+
+/// Does the first strong directional character in `text` belong to a right-to-left script?
+///
+/// Follows UAX #9 rules P2 and P3: characters with strong bidirectional class AL or R
+/// (Arabic, Hebrew, Syriac, Thaana…) give `true`; strong L characters (Latin, Greek,
+/// Cyrillic, CJK…) give `false`. Neutral, weak, and whitespace characters are skipped.
+pub fn first_strong_is_rtl(text: &str) -> bool {
+    for c in text.chars() {
+        if c == '\u{200F}' {
+            // Right-to-Left Mark (RLM)
+            return true;
+        }
+        if c == '\u{200E}' {
+            // Left-to-Right Mark (LRM)
+            return false;
+        }
+        if c.is_alphabetic() {
+            return is_rtl_script(c);
+        }
+    }
+    false
+}
+
+/// Helper checking if a char belongs to standard RTL Unicode blocks.
+pub fn is_rtl_script(c: char) -> bool {
+    matches!(
+        c,
+        '\u{0590}'..='\u{05FF}' // Hebrew
+        | '\u{0600}'..='\u{06FF}' // Arabic
+        | '\u{0700}'..='\u{074F}' // Syriac
+        | '\u{0750}'..='\u{077F}' // Arabic Supplement
+        | '\u{0780}'..='\u{07BF}' // Thaana
+        | '\u{0870}'..='\u{089F}' // Arabic Extended-B
+        | '\u{08A0}'..='\u{08FF}' // Arabic Extended-A
+        | '\u{FB1D}'..='\u{FB4F}' // Hebrew Presentation Forms
+        | '\u{FB50}'..='\u{FDFF}' // Arabic Presentation Forms-A
+        | '\u{FE70}'..='\u{FEFE}' // Arabic Presentation Forms-B
+    )
+}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn detects_arabic_and_kurdish() {
+        assert!(first_strong_is_rtl("مرحبا"));
+        assert!(first_strong_is_rtl("من ناوم هێڤاره"));
+        assert!(first_strong_is_rtl("سلام"));
+    }
+
+    #[test]
+    fn detects_hebrew() {
+        assert!(first_strong_is_rtl("שלום"));
+    }
+
+    #[test]
+    fn detects_latin_as_not_rtl() {
+        assert!(!first_strong_is_rtl("Hello"));
+        assert!(!first_strong_is_rtl("DeckCraft"));
+    }
+
+    #[test]
+    fn skips_neutrals_numbers_and_whitespace() {
+        assert!(first_strong_is_rtl("  123 مرحبا"));
+        assert!(first_strong_is_rtl("... (2024) سنة"));
+        assert!(!first_strong_is_rtl("  123 Hello"));
+        assert!(!first_strong_is_rtl(""));
+        assert!(!first_strong_is_rtl("   12345 "));
+    }
+
+    #[test]
+    fn honours_directional_marks() {
+        assert!(first_strong_is_rtl("\u{200F}Hello"));
+        assert!(!first_strong_is_rtl("\u{200E}مرحبا"));
+    }
+}

crates/model/src/edit.rs

@@ -401,6 +401,44 @@ pub fn char_move(body: &TextBody, pos: Pos, forward: bool) -> Pos {
     }
 }
 
+/// The position of the `n`th character of the body's plain text (`\n` between paragraphs).
+fn pos_of_char(body: &TextBody, mut n: usize) -> Pos {
+    for (pi, p) in body.paragraphs.iter().enumerate() {
+        let len = p.char_len();
+        if n <= len {
+            return (pi, n);
+        }
+        n -= len + 1;
+    }
+    end(body)
+}
+
+/// Make the body's plain text (paragraphs joined by `\n`) read `text`, as if it had been typed in
+/// place: only the span between the longest common prefix and suffix changes, so untouched text
+/// keeps its run and paragraph formatting and new text takes the formatting where it lands. Text
+/// that shares nothing with the old text replaces it as plain text.
+pub fn replace_text(body: &mut TextBody, text: &str) {
+    let old: Vec<char> = body.text().chars().collect();
+    let new: Vec<char> = text.chars().collect();
+    if old == new {
+        return;
+    }
+    let pre = old.iter().zip(&new).take_while(|(a, b)| a == b).count();
+    let room = old.len().min(new.len()) - pre;
+    let suf = old.iter().rev().zip(new.iter().rev()).take(room).take_while(|(a, b)| a == b).count();
+    if pre == 0 && suf == 0 {
+        *body = TextBody { body: body.body.clone(), list_style: body.list_style.clone(), ..TextBody::from_text(text) };
+        return;
+    }
+    let a = pos_of_char(body, pre);
+    let b = pos_of_char(body, old.len() - suf);
+    let at = delete(body, a, b);
+    let mid: String = new.get(pre..new.len() - suf).unwrap_or(&[]).iter().collect();
+    if !mid.is_empty() {
+        insert(body, at, &mid, None);
+    }
+}
+
 /// End of the body.
 pub fn end(body: &TextBody) -> Pos {
     let pi = body.paragraphs.len().saturating_sub(1);
@@ -676,4 +714,53 @@ mod tests {
         assert_eq!(next_case("hello. world is HERE"), "upper");
         assert_eq!(next_case("123"), "upper");
     }
+
+    /// Speaker notes: a bold heading over indented bullet points.
+    fn notes() -> TextBody {
+        use crate::text::{Bullet, ParaProps};
+        let mut b = body("Overview\nFirst point\nSecond point");
+        format(&mut b, (0, 0), (0, 8), &|p| p.bold = Some(true));
+        for p in b.paragraphs.iter_mut().skip(1) {
+            p.level = 1;
+            p.props =
+                ParaProps { margin_left: Some(36.0), indent: Some(-18.0), bullet: Some(Bullet::Char { char: "•".into() }), ..Default::default() };
+        }
+        b
+    }
+
+    #[test]
+    fn replace_text_keeps_formatting() {
+        let before = notes();
+        // Same text: nothing changes.
+        let mut b = before.clone();
+        replace_text(&mut b, "Overview\nFirst point\nSecond point");
+        assert_eq!(b, before);
+        // A word typed into a bullet: heading stays bold, bullets keep level, indent and bullet.
+        replace_text(&mut b, "Overview\nFirst main point\nSecond point");
+        assert_eq!(b.text(), "Overview\nFirst main point\nSecond point");
+        assert_eq!(b.paragraphs[0].runs[0].props.bold, Some(true));
+        assert_eq!(b.paragraphs[1].props, before.paragraphs[1].props);
+        assert_eq!((b.paragraphs[1].level, b.paragraphs[2].level), (1, 1));
+        // Typing at the end of the heading continues it in bold.
+        replace_text(&mut b, "Overview (5 min)\nFirst main point\nSecond point");
+        assert_eq!(b.paragraphs[0].runs.len(), 1);
+        assert_eq!(b.paragraphs[0].runs[0].props.bold, Some(true));
+        // Enter after a bullet starts another bullet; deleting one joins nothing else.
+        replace_text(&mut b, "Overview (5 min)\nFirst main point\nThird\nSecond point");
+        assert_eq!(b.paragraphs.len(), 4);
+        assert_eq!((b.paragraphs[2].level, &b.paragraphs[2].props), (1, &before.paragraphs[1].props));
+        replace_text(&mut b, "Overview (5 min)\nSecond point");
+        assert_eq!(b.text(), "Overview (5 min)\nSecond point");
+        assert_eq!(b.paragraphs[0].runs[0].props.bold, Some(true));
+        assert_eq!(b.paragraphs[1].level, 1);
+        // Text with nothing in common is new plain text.
+        replace_text(&mut b, "Plain");
+        assert_eq!(b, body("Plain"));
+        replace_text(&mut b, "");
+        assert!(b.is_empty());
+        // Into an empty body.
+        let mut e = TextBody::default();
+        replace_text(&mut e, "a\nb");
+        assert_eq!(e.text(), "a\nb");
+    }
 }

crates/model/src/lib.rs

@@ -8,6 +8,7 @@
 #![forbid(unsafe_code)]
 
 pub mod anim;
+pub mod bidi;
 pub mod chart;
 pub mod defaults;
 pub mod edit;
@@ -27,6 +28,7 @@ pub use deckcraft_geom::{Rect, Size, Xfrm};
 use serde::{Deserialize, Serialize};
 
 pub use anim::{AnimClass, AnimStart, Animation, Transition};
+pub use bidi::{first_strong_is_rtl, is_rtl_script};
 pub use chart::Chart;
 pub use style::{ColorBase, ColorRef, Effects, Fill, Line, ShapeStyle};
 pub use table::{Cell, Table};
@@ -315,6 +317,10 @@ pub enum ShapeKind {
         xml: String,
         preview: Option<MediaId>,
         label: String,
+        /// The parts its XML points to (SmartArt data, an OLE embedding…), so a save writes them
+        /// back: (relationship id used in `xml`, relationship type, the part as a media item).
+        #[serde(default, skip_serializing_if = "Vec::is_empty")]
+        parts: Vec<(String, String, MediaId)>,
     },
 }