feat: add image url base64 mode support

lib/src/chat/completion.dart

@@ -364,15 +364,45 @@ class ImageContent with _$ImageContent {
       _$ImageContentFromJson(json);
 }
 
+///By controlling the detail parameter, which has three options, low, high, or
+///auto, you have control over how the model processes the image and generates
+///its textual understanding. By default, the model will use the auto setting
+/// which will look at the image input size and decide if it should use the
+/// low or high setting.
+@JsonEnum(fieldRename: FieldRename.snake)
+enum ImageDetail {
+  auto,
+
+  /// low will disable the “high res” model. The model will receive a low-res
+  /// 512px x 512px version of the image, and represent the image with a budget
+  /// of 65 tokens. This allows the API to return faster responses and consume
+  /// fewer input tokens for use cases that do not require high detail.
+  low,
+
+  /// high will enable “high res” mode, which first allows the model to see the
+  /// low res image and then creates detailed crops of input images as 512px
+  /// squares based on the input image size. Each of the detailed crops uses
+  /// twice the token budget (65 tokens) for a total of 129 tokens.
+  high,
+}
+
 @freezed
 class ImageUrl with _$ImageUrl {
   const factory ImageUrl({
     /// Either a URL of the image or the base64 encoded image data.
     required String url,
 
     /// Specifies the detail level of the image.
-    @Default("auto") String detail,
+    @Default(ImageDetail.auto) ImageDetail detail,
   }) = _ImageUrl;
+  factory ImageUrl.base64({
+    required List<int> image,
+    String mimeType = "image/jpeg",
+    ImageDetail detail = ImageDetail.auto,
+  }) {
+    final url = "data:$mimeType;base64,${base64Encode(image)}";
+    return ImageUrl(url: url, detail: detail);
+  }
 
   factory ImageUrl.fromJson(Map<String, dynamic> json) =>
       _$ImageUrlFromJson(json);

lib/src/chat/completion.freezed.dart

@@ -3096,7 +3096,7 @@ mixin _$ImageUrl {
   String get url => throw _privateConstructorUsedError;
 
   /// Specifies the detail level of the image.
-  String get detail => throw _privateConstructorUsedError;
+  ImageDetail get detail => throw _privateConstructorUsedError;
 
   Map<String, dynamic> toJson() => throw _privateConstructorUsedError;
   @JsonKey(ignore: true)
@@ -3109,7 +3109,7 @@ abstract class $ImageUrlCopyWith<$Res> {
   factory $ImageUrlCopyWith(ImageUrl value, $Res Function(ImageUrl) then) =
       _$ImageUrlCopyWithImpl<$Res, ImageUrl>;
   @useResult
-  $Res call({String url, String detail});
+  $Res call({String url, ImageDetail detail});
 }
 
 /// @nodoc
@@ -3136,7 +3136,7 @@ class _$ImageUrlCopyWithImpl<$Res, $Val extends ImageUrl>
       detail: null == detail
           ? _value.detail
           : detail // ignore: cast_nullable_to_non_nullable
-              as String,
+              as ImageDetail,
     ) as $Val);
   }
 }
@@ -3149,7 +3149,7 @@ abstract class _$$ImageUrlImplCopyWith<$Res>
       __$$ImageUrlImplCopyWithImpl<$Res>;
   @override
   @useResult
-  $Res call({String url, String detail});
+  $Res call({String url, ImageDetail detail});
 }
 
 /// @nodoc
@@ -3174,15 +3174,15 @@ class __$$ImageUrlImplCopyWithImpl<$Res>
       detail: null == detail
           ? _value.detail
           : detail // ignore: cast_nullable_to_non_nullable
-              as String,
+              as ImageDetail,
     ));
   }
 }
 
 /// @nodoc
 @JsonSerializable()
 class _$ImageUrlImpl implements _ImageUrl {
-  const _$ImageUrlImpl({required this.url, this.detail = "auto"});
+  const _$ImageUrlImpl({required this.url, this.detail = ImageDetail.auto});
 
   factory _$ImageUrlImpl.fromJson(Map<String, dynamic> json) =>
       _$$ImageUrlImplFromJson(json);
@@ -3194,7 +3194,7 @@ class _$ImageUrlImpl implements _ImageUrl {
   /// Specifies the detail level of the image.
   @override
   @JsonKey()
-  final String detail;
+  final ImageDetail detail;
 
   @override
   String toString() {
@@ -3229,8 +3229,8 @@ class _$ImageUrlImpl implements _ImageUrl {
 }
 
 abstract class _ImageUrl implements ImageUrl {
-  const factory _ImageUrl({required final String url, final String detail}) =
-      _$ImageUrlImpl;
+  const factory _ImageUrl(
+      {required final String url, final ImageDetail detail}) = _$ImageUrlImpl;
 
   factory _ImageUrl.fromJson(Map<String, dynamic> json) =
       _$ImageUrlImpl.fromJson;
@@ -3242,7 +3242,7 @@ abstract class _ImageUrl implements ImageUrl {
   @override
 
   /// Specifies the detail level of the image.
-  String get detail;
+  ImageDetail get detail;
   @override
   @JsonKey(ignore: true)
   _$$ImageUrlImplCopyWith<_$ImageUrlImpl> get copyWith =>

test/chat_completion_test.dart

@@ -1,4 +1,5 @@
 import 'dart:convert';
+import 'dart:io';
 
 import 'package:cancellation_token_http/http.dart';
 import 'package:cancellation_token_http/testing.dart';
@@ -151,14 +152,26 @@ void main() {
                 "https://pics0.baidu.com/feed/314e251f95cad1c84595a5ad29667204c83d51f7.jpeg@f_auto?token=8ad7fa4a5a222a9039b02f92114bfc07"),
       );
 
-      final request =
-          ChatCompletionRequest(model: Models.gpt4_1106VisonPreview, messages: [
-        ChatMessage.system(content: "Hello, how are you?"),
-        ChatMessage.user(content: [
-          TextContent(text: "show me what you see in the following image"),
-          ic,
-        ]),
-      ]);
+      final f = File("test/gpt4v-demo.webp");
+      final ic2 = ImageContent(
+          imageUrl: ImageUrl.base64(
+        image: f.readAsBytesSync(),
+      ));
+
+      final request = ChatCompletionRequest(
+          model: Models.gpt4_1106VisonPreview,
+          maxTokens: 500,
+          messages: [
+            ChatMessage.system(content: "Hello, how are you?"),
+            ChatMessage.user(content: [
+              TextContent(
+                text:
+                    "show me what you see in the following image? Are the two images the same?",
+              ),
+              ic,
+              ic2,
+            ]),
+          ]);
       final result = await proxyedClient.sendChatCompletion(request);
       print(result);
     });