feat: send didChange, didSave and didClose events to language server

src/Project.zig

@@ -2,6 +2,8 @@ const std = @import("std");
 const tp = @import("thespian");
 const cbor = @import("cbor");
 const root = @import("root");
+const dizzy = @import("dizzy");
+const Buffer = @import("Buffer");
 const builtin = @import("builtin");
 
 const LSP = @import("LSP.zig");
@@ -185,6 +187,129 @@ pub fn did_open(self: *Self, from: tp.pid_ref, file_path: []const u8, file_type:
     });
 }
 
+pub fn did_change(self: *Self, file_path: []const u8, version: usize, root_dst_addr: usize, root_src_addr: usize) !void {
+    const lsp = try self.get_file_lsp(file_path);
+    const uri = self.make_URI(file_path) catch |e| return tp.exit_error(e);
+    defer self.a.free(uri);
+
+    const root_dst: Buffer.Root = if (root_dst_addr == 0) return else @ptrFromInt(root_dst_addr);
+    const root_src: Buffer.Root = if (root_src_addr == 0) return else @ptrFromInt(root_src_addr);
+
+    var dizzy_edits = std.ArrayListUnmanaged(dizzy.Edit){};
+    var dst = std.ArrayList(u8).init(self.a);
+    var src = std.ArrayList(u8).init(self.a);
+    var scratch = std.ArrayListUnmanaged(u32){};
+    var edits_cb = std.ArrayList(u8).init(self.a);
+    const writer = edits_cb.writer();
+
+    defer {
+        edits_cb.deinit();
+        dst.deinit();
+        src.deinit();
+        scratch.deinit(self.a);
+        dizzy_edits.deinit(self.a);
+    }
+
+    try root_dst.store(dst.writer());
+    try root_src.store(src.writer());
+
+    const scratch_len = 4 * (dst.items.len + src.items.len) + 2;
+    try scratch.ensureTotalCapacity(self.a, scratch_len);
+    scratch.items.len = scratch_len;
+
+    try dizzy.PrimitiveSliceDiffer(u8).diff(self.a, &dizzy_edits, src.items, dst.items, scratch.items);
+
+    var lines_dst: usize = 0;
+    var pos_src: usize = 0;
+    var pos_dst: usize = 0;
+    var last_offset: usize = 0;
+    var edits_count: usize = 0;
+
+    for (dizzy_edits.items) |dizzy_edit| {
+        switch (dizzy_edit.kind) {
+            .equal => {
+                const dist = dizzy_edit.range.end - dizzy_edit.range.start;
+                pos_src += dist;
+                pos_dst += dist;
+                scan_char(src.items[dizzy_edit.range.start..dizzy_edit.range.end], &lines_dst, '\n', &last_offset);
+            },
+            .insert => {
+                const dist = dizzy_edit.range.end - dizzy_edit.range.start;
+                pos_src += 0;
+                pos_dst += dist;
+                const line_start_dst: usize = lines_dst;
+                scan_char(dst.items[dizzy_edit.range.start..dizzy_edit.range.end], &lines_dst, '\n', null);
+                try cbor.writeValue(writer, .{
+                    .range = .{
+                        .start = .{ .line = line_start_dst, .character = last_offset },
+                        .end = .{ .line = line_start_dst, .character = last_offset },
+                    },
+                    .text = dst.items[dizzy_edit.range.start..dizzy_edit.range.end],
+                });
+                edits_count += 1;
+            },
+            .delete => {
+                const dist = dizzy_edit.range.end - dizzy_edit.range.start;
+                pos_src += dist;
+                pos_dst += 0;
+                var line_end_dst: usize = lines_dst;
+                var offset_end_dst: usize = last_offset;
+                scan_char(src.items[dizzy_edit.range.start..dizzy_edit.range.end], &line_end_dst, '\n', &offset_end_dst);
+                if (lines_dst == line_end_dst) offset_end_dst = last_offset + dist;
+                try cbor.writeValue(writer, .{
+                    .range = .{
+                        .start = .{ .line = lines_dst, .character = last_offset },
+                        .end = .{ .line = line_end_dst, .character = offset_end_dst },
+                    },
+                    .text = "",
+                });
+                edits_count += 1;
+            },
+        }
+    }
+
+    var msg = std.ArrayList(u8).init(self.a);
+    defer msg.deinit();
+    const msg_writer = msg.writer();
+    try cbor.writeMapHeader(msg_writer, 2);
+    try cbor.writeValue(msg_writer, "textDocument");
+    try cbor.writeValue(msg_writer, .{ .uri = uri, .version = version });
+    try cbor.writeValue(msg_writer, "contentChanges");
+    try cbor.writeArrayHeader(msg_writer, edits_count);
+    _ = try msg_writer.write(edits_cb.items);
+
+    try lsp.send_notification_raw("textDocument/didChange", msg.items);
+}
+
+fn scan_char(chars: []const u8, lines: *usize, char: u8, last_offset: ?*usize) void {
+    var pos = chars;
+    while (pos.len > 0) {
+        if (pos[0] == char) {
+            if (last_offset) |off| off.* = pos.len - 1;
+            lines.* += 1;
+        }
+        pos = pos[1..];
+    }
+}
+
+pub fn did_save(self: *Self, file_path: []const u8) tp.result {
+    const lsp = try self.get_file_lsp(file_path);
+    const uri = self.make_URI(file_path) catch |e| return tp.exit_error(e);
+    defer self.a.free(uri);
+    try lsp.send_notification("textDocument/didSave", .{
+        .textDocument = .{ .uri = uri },
+    });
+}
+
+pub fn did_close(self: *Self, file_path: []const u8) tp.result {
+    const lsp = try self.get_file_lsp(file_path);
+    const uri = self.make_URI(file_path) catch |e| return tp.exit_error(e);
+    defer self.a.free(uri);
+    try lsp.send_notification("textDocument/didClose", .{
+        .textDocument = .{ .uri = uri },
+    });
+}
+
 pub fn goto_definition(self: *Self, from: tp.pid_ref, file_path: []const u8, row: usize, col: usize) !void {
     const lsp = try self.get_file_lsp(file_path);
     const uri = self.make_URI(file_path) catch |e| return tp.exit_error(e);