From 797cae2ef8409200980b94a0f4e636be16e79bf2 Mon Sep 17 00:00:00 2001
From: Pierre Tachoire <pierre@lightpanda.io>
Date: Mon, 23 Mar 2026 14:26:27 +0100
Subject: [PATCH] encode captured response body during CDP call

---
 src/cdp/cdp.zig             | 23 ++++++++---------------
 src/cdp/domains/network.zig | 17 ++++++++++++++---
 2 files changed, 22 insertions(+), 18 deletions(-)

diff --git a/src/cdp/cdp.zig b/src/cdp/cdp.zig
index e003e935..b55a923d 100644
--- a/src/cdp/cdp.zig
+++ b/src/cdp/cdp.zig
@@ -326,7 +326,7 @@ pub fn BrowserContext(comptime CDP_T: type) type {
     const AXNode = @import("AXNode.zig");
 
     const CapturedResponse = struct {
-        encode: enum { none, base64 },
+        must_encode: bool,
         data: std.ArrayList(u8),
     };
 
@@ -648,22 +648,22 @@ pub fn BrowserContext(comptime CDP_T: type) type {
             if (!gop.found_existing) {
                 gop.value_ptr.* = .{
                     .data = .empty,
-                    // Encode the data in base64 by default, but use none
-                    // encoding for well known content-type.
-                    .encode = blk: {
+                    // Encode the data in base64 by default, but don't encode
+                    // for well known content-type.
+                    .must_encode = blk: {
                         const transfer = msg.transfer;
                         if (transfer.response_header.?.contentType()) |ct| {
                             const mime = try Mime.parse(ct);
 
                             if (!mime.isText()) {
-                                break :blk .base64;
+                                break :blk true;
                             }
 
                             if (std.mem.eql(u8, "UTF-8", mime.charsetString())) {
-                                break :blk .none;
+                                break :blk false;
                             }
                         }
-                        break :blk .base64;
+                        break :blk true;
                     },
                 };
             }
@@ -683,14 +683,7 @@ pub fn BrowserContext(comptime CDP_T: type) type {
             const id = msg.transfer.id;
             const resp = self.captured_responses.getPtr(id) orelse lp.assert(false, "onHttpResponseData missinf captured response", .{});
 
-            if (resp.encode == .none) {
-                return resp.data.appendSlice(arena, msg.data);
-            }
-
-            const encoded_len = std.base64.standard.Encoder.calcSize(msg.data.len);
-            const start = resp.data.items.len;
-            try resp.data.resize(arena, start + encoded_len);
-            _ = std.base64.standard.Encoder.encode(resp.data.items[start..], msg.data);
+            return resp.data.appendSlice(arena, msg.data);
         }
 
         pub fn onHttpRequestAuthRequired(ctx: *anyopaque, data: *const Notification.RequestAuthRequired) !void {
diff --git a/src/cdp/domains/network.zig b/src/cdp/domains/network.zig
index f26e2037..11e0142c 100644
--- a/src/cdp/domains/network.zig
+++ b/src/cdp/domains/network.zig
@@ -210,9 +210,20 @@ fn getResponseBody(cmd: anytype) !void {
     const bc = cmd.browser_context orelse return error.BrowserContextNotLoaded;
     const resp = bc.captured_responses.getPtr(request_id) orelse return error.RequestNotFound;
 
-    try cmd.sendResult(.{
-        .body = resp.data.items,
-        .base64Encoded = resp.encode == .base64,
+    if (!resp.must_encode) {
+        return cmd.sendResult(.{
+            .body = resp.data.items,
+            .base64Encoded = false,
+        }, .{});
+    }
+
+    const encoded_len = std.base64.standard.Encoder.calcSize(resp.data.items.len);
+    const encoded = try cmd.arena.alloc(u8, encoded_len);
+    _ = std.base64.standard.Encoder.encode(encoded, resp.data.items);
+
+    return cmd.sendResult(.{
+        .body = encoded,
+        .base64Encoded = true,
     }, .{});
 }