Use 8.3 file names.

1 files changed, 102 insertions, 4 deletions

diff --git a/src/eval.zig b/src/eval.zig
index 2b55c21..91c03b0 100644
--- a/src/eval.zig
+++ b/src/eval.zig
@@ -80,14 +80,35 @@ fn formatDosPath(allocator: Allocator, path: []const u8) ![]const u8 {
     defer result.deinit();
 
     // Convert path to DOS format with uppercase drive letter and backslashes
+    var converted_path = ArrayList(u8).init(allocator);
+    defer converted_path.deinit();
+
     for (path) |ch| {
         if (ch == '/') {
-            try result.append('\\');
+            try converted_path.append('\\');
         } else {
-            try result.append(std.ascii.toUpper(ch));
+            try converted_path.append(std.ascii.toUpper(ch));
         }
     }
 
+    // Split into components and convert each to 8.3 format
+    var it = std.mem.splitScalar(u8, converted_path.items, '\\');
+    var first = true;
+
+    while (it.next()) |component| {
+        if (component.len == 0) continue;
+
+        if (!first) {
+            try result.append('\\');
+        }
+        first = false;
+
+        // Convert component to 8.3 format
+        const short_name = try convertTo83(allocator, component);
+        defer allocator.free(short_name);
+        try result.appendSlice(short_name);
+    }
+
     // Ensure it starts with a drive letter if it's an absolute path
     if (result.items.len == 0 or (result.items.len >= 1 and result.items[0] == '\\')) {
         var prefixed = ArrayList(u8).init(allocator);
@@ -103,6 +124,79 @@ fn formatDosPath(allocator: Allocator, path: []const u8) ![]const u8 {
     return allocator.dupe(u8, result.items);
 }
 
+fn convertTo83(allocator: Allocator, filename: []const u8) ![]const u8 {
+    // Handle special directories
+    if (std.mem.eql(u8, filename, ".") or std.mem.eql(u8, filename, "..")) {
+        return allocator.dupe(u8, filename);
+    }
+
+    // Handle drive letters (like C:)
+    if (filename.len == 2 and filename[1] == ':') {
+        return allocator.dupe(u8, filename);
+    }
+
+    // Split filename and extension
+    var name_part: []const u8 = filename;
+    var ext_part: []const u8 = "";
+
+    if (std.mem.lastIndexOf(u8, filename, ".")) |dot_pos| {
+        if (dot_pos > 0) { // Don't treat leading dot as extension separator
+            name_part = filename[0..dot_pos];
+            ext_part = filename[dot_pos + 1 ..];
+        }
+    }
+
+    // Clean name part (remove spaces and invalid chars, convert to uppercase)
+    var clean_name = ArrayList(u8).init(allocator);
+    defer clean_name.deinit();
+
+    for (name_part) |ch| {
+        if (std.ascii.isAlphanumeric(ch)) {
+            try clean_name.append(std.ascii.toUpper(ch));
+        } else if (ch == '-' or ch == '_') {
+            try clean_name.append(ch);
+        }
+        // Skip spaces and other invalid characters
+    }
+
+    // Clean extension part (max 3 chars, uppercase)
+    var clean_ext = ArrayList(u8).init(allocator);
+    defer clean_ext.deinit();
+
+    for (ext_part) |ch| {
+        if (clean_ext.items.len >= 3) break;
+        if (std.ascii.isAlphanumeric(ch)) {
+            try clean_ext.append(std.ascii.toUpper(ch));
+        }
+    }
+
+    // Build 8.3 filename
+    var result = ArrayList(u8).init(allocator);
+    defer result.deinit();
+
+    if (clean_name.items.len <= 8 and clean_ext.items.len <= 3) {
+        // Name fits in 8.3, use as-is
+        try result.appendSlice(clean_name.items);
+        if (clean_ext.items.len > 0) {
+            try result.append('.');
+            try result.appendSlice(clean_ext.items);
+        }
+    } else {
+        // Need to abbreviate with ~1
+        const max_name_len = if (clean_name.items.len > 6) 6 else clean_name.items.len;
+        try result.appendSlice(clean_name.items[0..max_name_len]);
+        try result.appendSlice("~1");
+
+        if (clean_ext.items.len > 0) {
+            try result.append('.');
+            const max_ext_len = if (clean_ext.items.len > 3) 3 else clean_ext.items.len;
+            try result.appendSlice(clean_ext.items[0..max_ext_len]);
+        }
+    }
+
+    return allocator.dupe(u8, result.items);
+}
+
 fn formatDosDateTime(allocator: Allocator, timestamp_secs: i64) ![]const u8 {
     const epoch_seconds = @as(u64, @intCast(@max(timestamp_secs, 0)));
     const epoch_day = @divFloor(epoch_seconds, std.time.s_per_day);
@@ -303,13 +397,17 @@ fn executeCommandWithOutput(command: Command, allocator: Allocator, output_captu
                         const date_time = try formatDosDateTime(allocator, @intCast(mtime_secs));
                         defer allocator.free(date_time);
 
+                        // Convert filename to 8.3 format
+                        const short_name = try convertTo83(allocator, entry.name);
+                        defer allocator.free(short_name);
+
                         switch (entry.kind) {
                             .directory => {
-                                try output_buffer.writer().print("{s}  <DIR>          {s}\n", .{ date_time, entry.name });
+                                try output_buffer.writer().print("{s}  <DIR>          {s}\n", .{ date_time, short_name });
                                 dir_count += 1;
                             },
                             .file => {
-                                try output_buffer.writer().print("{s}  {d:>14} {s}\n", .{ date_time, stat.size, entry.name });
+                                try output_buffer.writer().print("{s}  {d:>14} {s}\n", .{ date_time, stat.size, short_name });
                                 file_count += 1;
                                 total_file_bytes += stat.size;
                             },