From b1eb199e7bea7742f632179d61a1132409535b7d Mon Sep 17 00:00:00 2001
From: "KOSMOS, Tzushih.K" <48860861+kisaraki@users.noreply.github.com>
Date: Mon, 24 Aug 2026 13:50:23 +0800
Subject: [PATCH] feat: show recent files in open dialog

---
 crates/edit/src/bin/edit/draw_filepicker.rs |  63 +++++++++-
 crates/edit/src/bin/edit/main.rs            |  13 +-
 crates/edit/src/bin/edit/settings.rs        | 132 +++++++++++++++++++-
 i18n/edit.toml                              |  10 ++
 4 files changed, 207 insertions(+), 11 deletions(-)

diff --git a/crates/edit/src/bin/edit/draw_filepicker.rs b/crates/edit/src/bin/edit/draw_filepicker.rs
index e71b7f81ec3..d3355528b5a 100644
--- a/crates/edit/src/bin/edit/draw_filepicker.rs
+++ b/crates/edit/src/bin/edit/draw_filepicker.rs
@@ -14,6 +14,7 @@ use stdext::arena::scratch_arena;
 use stdext::collections::BVec;
 
 use crate::localization::*;
+use crate::settings::Settings;
 use crate::state::*;
 
 pub fn draw_file_picker(ctx: &mut Context, state: &mut State) {
@@ -27,9 +28,21 @@ pub fn draw_file_picker(ctx: &mut Context, state: &mut State) {
         }
     }
 
+    // EN: Only Open receives a lower MRU pane; Save As keeps the original layout.
+    // 中文：僅「開啟舊檔」加入下方最近檔案欄；另存新檔維持原配置。
+    let opening_file = state.wants_file_picker == StateFilePicker::Open;
+    let recent_files =
+        if opening_file { Settings::borrow().recent_files.clone() } else { Vec::new() };
     let width = (ctx.size().width - 20).max(10);
-    let height = (ctx.size().height - 10).max(10);
+    let height = if opening_file {
+        (ctx.size().height - 4).max(12)
+    } else {
+        (ctx.size().height - 10).max(10)
+    };
+    let recent_pane_height = if opening_file { (height / 3).clamp(1, 5) } else { 0 };
+    let recent_reserved_rows = if opening_file { recent_pane_height + 3 } else { 0 };
     let mut doit = None;
+    let mut recent_open = None;
     let mut done = false;
 
     ctx.modal_begin(
@@ -144,7 +157,7 @@ pub fn draw_file_picker(ctx: &mut Context, state: &mut State) {
                 // -1 for the label (top)
                 // -1 for the label (bottom)
                 // -1 for the editline (bottom)
-                height: height - 3,
+                height: (height - 3 - recent_reserved_rows).max(3),
             },
         );
         ctx.attr_background_rgba(ctx.indexed_alpha(IndexedColor::Black, 1, 4));
@@ -170,6 +183,40 @@ pub fn draw_file_picker(ctx: &mut Context, state: &mut State) {
         }
         ctx.scrollarea_end();
 
+        if opening_file {
+            // EN: Every absolute path is a clickable entry in the lower pane.
+            // 中文：每一筆絕對路徑都是下方窗格中可點選開啟的項目。
+            ctx.label("recent-files-label", loc(LocId::FileOpenRecentFiles));
+            ctx.attr_padding(Rect::three(1, 1, 0));
+            ctx.scrollarea_begin(
+                "recent-files-pane",
+                Size { width: 0, height: recent_pane_height },
+            );
+            ctx.attr_border();
+            ctx.attr_focus_well();
+            ctx.attr_background_rgba(ctx.indexed_alpha(IndexedColor::Black, 1, 4));
+            {
+                if recent_files.is_empty() {
+                    ctx.label("recent-files-empty", loc(LocId::FileOpenRecentEmpty));
+                    ctx.attr_padding(Rect::two(0, 1));
+                } else {
+                    for recent in &recent_files {
+                        let display = recent.to_string_lossy();
+                        if ctx.button(
+                            "recent-file",
+                            &display,
+                            ButtonStyle::default().bracketed(false),
+                        ) {
+                            recent_open = Some(recent.clone());
+                        }
+                        ctx.attr_overflow(Overflow::TruncateMiddle);
+                        ctx.attr_padding(Rect::two(0, 1));
+                    }
+                }
+            }
+            ctx.scrollarea_end();
+        }
+
         if contains_focus
             && (ctx.consume_shortcut(vk::BACK) || ctx.consume_shortcut(kbmod::ALT | vk::UP))
         {
@@ -188,6 +235,10 @@ pub fn draw_file_picker(ctx: &mut Context, state: &mut State) {
                 state.file_picker_overwrite_warning = doit.take();
             }
         }
+
+        if let Some(path) = recent_open.take() {
+            doit = Some(path);
+        }
     }
     if ctx.modal_end() {
         done = true;
@@ -241,15 +292,19 @@ pub fn draw_file_picker(ctx: &mut Context, state: &mut State) {
     }
 
     if let Some(path) = doit {
-        let res = if state.wants_file_picker == StateFilePicker::Open {
+        let opening_file = state.wants_file_picker == StateFilePicker::Open;
+        let res = if opening_file {
             state.documents.add_file_path(&path).map(|_| ())
         } else if let Some(doc) = state.documents.active_mut() {
-            doc.save(Some(path))
+            doc.save(Some(path.clone()))
         } else {
             Ok(())
         };
         match res {
             Ok(..) => {
+                if opening_file && let Err(err) = Settings::record_recent_file(&path) {
+                    error_log_add(ctx, state, err);
+                }
                 ctx.needs_rerender();
                 done = true;
             }
diff --git a/crates/edit/src/bin/edit/main.rs b/crates/edit/src/bin/edit/main.rs
index 27ae7fab6c0..25531a6db5f 100644
--- a/crates/edit/src/bin/edit/main.rs
+++ b/crates/edit/src/bin/edit/main.rs
@@ -289,9 +289,16 @@ fn handle_args(state: &mut State) -> apperr::Result<bool> {
     }
 
     for (p, goto) in &paths {
-        let doc = state.documents.add_file_path(p)?;
-        if let Some(goto) = goto {
-            doc.cursor_move_to_goto(*goto);
+        {
+            let doc = state.documents.add_file_path(p)?;
+            if let Some(goto) = goto {
+                doc.cursor_move_to_goto(*goto);
+            }
+        }
+        // EN: Command-line and shell opens participate in the same recent-file list.
+        // 中文：命令列與系統殼層開啟的檔案也納入同一份最近檔案清單。
+        if let Err(err) = Settings::record_recent_file(p) {
+            state.add_error(err);
         }
     }
 
diff --git a/crates/edit/src/bin/edit/settings.rs b/crates/edit/src/bin/edit/settings.rs
index e29b0970a9b..93c78be8d2b 100644
--- a/crates/edit/src/bin/edit/settings.rs
+++ b/crates/edit/src/bin/edit/settings.rs
@@ -1,9 +1,10 @@
-use std::path::PathBuf;
+use std::fmt::Write as _;
+use std::path::{Path, PathBuf};
 
 use edit::buffer::TextBuffer;
 use edit::cell::{Ref, SemiRefCell};
-use edit::json;
 use edit::lsh::{LANGUAGES, Language};
+use edit::{json, path as edit_path};
 use stdext::arena::{read_to_string, scratch_arena};
 use stdext::arena_format;
 
@@ -12,6 +13,7 @@ use crate::apperr;
 pub struct Settings {
     pub path: PathBuf,
     pub file_associations: Vec<(String, &'static Language)>,
+    pub recent_files: Vec<PathBuf>,
 }
 
 struct SettingsCell(SemiRefCell<Settings>);
@@ -22,13 +24,14 @@ impl Settings {
     /// Fills the given settings.json text buffer with some initial contents for convenience.
     pub fn bootstrap(tb: &mut TextBuffer) {
         tb.set_crlf(false);
-        tb.write_raw(b"{\n}\n");
+        let contents = Self::borrow().to_json();
+        tb.write_raw(contents.as_bytes());
         tb.cursor_move_to_logical(Default::default());
         tb.mark_as_clean();
     }
 
     const fn new() -> Self {
-        Settings { path: PathBuf::new(), file_associations: Vec::new() }
+        Settings { path: PathBuf::new(), file_associations: Vec::new(), recent_files: Vec::new() }
     }
 
     pub fn borrow() -> Ref<'static, Settings> {
@@ -82,8 +85,103 @@ impl Settings {
             }
         }
 
+        // EN: Persist at most five unique absolute paths, newest first.
+        // 中文：最近開啟檔案最多保存五筆不重複的絕對路徑，最新項目在前。
+        if let Some(value) = root.get("files.recent") {
+            let Some(values) = value.as_array() else {
+                return Err(apperr::Error::SettingsInvalid("files.recent"));
+            };
+            for value in values.iter().take(5) {
+                let Some(value) = value.as_str() else {
+                    return Err(apperr::Error::SettingsInvalid("files.recent"));
+                };
+                let path = PathBuf::from(value);
+                if !path.is_absolute() {
+                    return Err(apperr::Error::SettingsInvalid("files.recent"));
+                }
+                let path = edit_path::normalize(&path);
+                if !self.recent_files.contains(&path) {
+                    self.recent_files.push(path);
+                }
+            }
+        }
+
         Ok(())
     }
+
+    /// EN: Moves a successfully opened file to the front of the recent-file list.
+    /// 中文：將成功開啟的檔案移至最近檔案清單最前方。
+    pub fn record_recent_file(path: &Path) -> apperr::Result<()> {
+        let absolute = if path.is_absolute() {
+            path.to_path_buf()
+        } else {
+            std::env::current_dir()?.join(path)
+        };
+        let absolute = edit_path::normalize(&absolute);
+        let settings = &mut *SETTINGS.0.borrow_mut();
+        settings.remember_recent_file(absolute);
+        settings.save()
+    }
+
+    fn remember_recent_file(&mut self, path: PathBuf) {
+        self.recent_files.retain(|recent| recent != &path);
+        self.recent_files.insert(0, path);
+        self.recent_files.truncate(5);
+    }
+
+    fn save(&self) -> apperr::Result<()> {
+        if self.path.as_os_str().is_empty() {
+            return Ok(());
+        }
+        if let Some(parent) = self.path.parent() {
+            std::fs::create_dir_all(parent)?;
+        }
+        std::fs::write(&self.path, self.to_json())?;
+        Ok(())
+    }
+
+    fn to_json(&self) -> String {
+        // EN: Serialize generated settings with LF on every supported platform.
+        // 中文：自行序列化設定，確保所有支援平台皆固定使用 LF。
+        let mut contents = String::from("{\n  \"files.associations\": {");
+        for (index, (pattern, language)) in self.file_associations.iter().enumerate() {
+            contents.push_str(if index == 0 { "\n    " } else { ",\n    " });
+            write_json_string(&mut contents, pattern);
+            contents.push_str(": ");
+            write_json_string(&mut contents, language.id);
+        }
+        if !self.file_associations.is_empty() {
+            contents.push_str("\n  ");
+        }
+        contents.push_str("},\n  \"files.recent\": [");
+        for (index, path) in self.recent_files.iter().enumerate() {
+            contents.push_str(if index == 0 { "\n    " } else { ",\n    " });
+            write_json_string(&mut contents, &path.to_string_lossy());
+        }
+        if !self.recent_files.is_empty() {
+            contents.push_str("\n  ");
+        }
+        contents.push_str("]\n}\n");
+        contents
+    }
+}
+
+fn write_json_string(output: &mut String, value: &str) {
+    output.push('"');
+    for ch in value.chars() {
+        match ch {
+            '"' => output.push_str("\\\""),
+            '\\' => output.push_str("\\\\"),
+            '\u{08}' => output.push_str("\\b"),
+            '\u{0c}' => output.push_str("\\f"),
+            '\n' => output.push_str("\\n"),
+            '\r' => output.push_str("\\r"),
+            '\t' => output.push_str("\\t"),
+            '\0'..='\u{1f}' => _ = write!(output, "\\u{:04x}", ch as u32),
+            _ => output.push(ch),
+        }
+    }
+    output.push('"');
 }
 
 fn settings_json_path() -> Option<PathBuf> {
@@ -117,3 +215,29 @@ fn config_dir() -> Option<PathBuf> {
             .map(|p| push(p, "msedit"))
     }
 }
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn recent_files_keep_the_newest_unique_five_paths() {
+        let mut settings = Settings::new();
+        for name in ["one", "two", "three", "four", "five", "six", "four"] {
+            settings.remember_recent_file(PathBuf::from(name));
+        }
+        assert_eq!(
+            settings.recent_files,
+            ["four", "six", "five", "three", "two"].map(PathBuf::from)
+        );
+    }
+
+    #[test]
+    fn recent_file_json_uses_lf() {
+        let mut settings = Settings::new();
+        settings.recent_files.push(PathBuf::from("C:/notes/readme.md"));
+        let json = settings.to_json();
+        assert!(json.contains("\"files.recent\""));
+        assert!(!json.contains("\r\n"));
+    }
+}
diff --git a/i18n/edit.toml b/i18n/edit.toml
index 11039636308..23f68968b2d 100644
--- a/i18n/edit.toml
+++ b/i18n/edit.toml
@@ -359,6 +359,16 @@ vi = "Mở tệp…"
 zh-hans = "打开文件…"
 zh-hant = "開啟舊檔…"
 
+[FileOpenRecentFiles]
+en = "Recent files (last 5; click to open)"
+zh-hans = "最近打开的文件（最多5笔，单击打开）"
+zh-hant = "最近開啟的檔案（最多5筆，單擊開啟）"
+
+[FileOpenRecentEmpty]
+en = "No recently opened files"
+zh-hans = "没有最近打开的文件"
+zh-hant = "沒有最近開啟的檔案"
+
 [FileSave]
 en = "Save"
 ar = "حفظ"