The-Agency/lib/src/api/request_builder.dart

// Request builder to construct Anthropic Message API requests
// Ported from old_repo/services/api/claude.ts

import "dart:io";
import "api_types.dart";

// builds a message api request with all the standard options
class MessageRequestBuilder {
  final String model;
  final int maxTokens;
  final List<Map<String, dynamic>> messages;

  String? _systemPrompt;
  double? _temperature;
  List<Map<String, dynamic>>? _tools;
  String? _toolChoice;
  Map<String, dynamic>? _metadata;


  MessageRequestBuilder({
    required this.model,
    required this.maxTokens,
    required this.messages,
  });

  MessageRequestBuilder withSystem(String system) {
    _systemPrompt = system;
    return this;
  }

  MessageRequestBuilder withTemperature(double temp) {
    _temperature = temp;
    return this;
  }

  MessageRequestBuilder withTools(List<Map<String, dynamic>> tools) {
    _tools = tools;
    return this;
  }

  MessageRequestBuilder withToolChoice(String choice) {
    _toolChoice = choice;
    return this;
  }

  MessageRequestBuilder withMetadata(Map<String, dynamic> metadata) {
    _metadata = metadata;
    return this;
  }

  MessageRequest build() {
    return MessageRequest(
      model: model,
      maxTokens: maxTokens,
      messages: messages,
      systemPrompt: _systemPrompt,
      temperature: _temperature,
      tools: _tools,
      toolChoice: _toolChoice,
      metadata: _metadata,
    );
  }
}

// helpers to add headers for API requests
class HeaderBuilder {
  final Map<String, String> _headers = {};

  HeaderBuilder() {
    _initializeDefaultHeaders();
  }

  void _initializeDefaultHeaders() {
    // Add standard headers for API requests
    final env = Platform.environment;

    // Session tracking
    if (env.containsKey("CLAUDE_CODE_SESSION_ID")) {
      _headers["X-Claude-Code-Session-Id"] = env["CLAUDE_CODE_SESSION_ID"]!;
    }

    // Remote tracking (if in a container)
    if (env.containsKey("CLAUDE_CODE_CONTAINER_ID")) {
      _headers["x-claude-remote-container-id"] = env["CLAUDE_CODE_CONTAINER_ID"]!;
    }

    if (env.containsKey("CLAUDE_CODE_REMOTE_SESSION_ID")) {
      _headers["x-claude-remote-session-id"] = env["CLAUDE_CODE_REMOTE_SESSION_ID"]!;
    }

    // App identifier
    _headers["x-app"] = "cli";

    // User agent from utils would go here (TODO when http client created)
    _headers["User-Agent"] = "clawd_code/0.1.0";
  }

  void addCustomHeader(String name, String value) {
    _headers[name] = value;
  }

  void addAuthHeader(String apiKey) {
    _headers["Authorization"] = "Bearer $apiKey";
  }

  void addOpenRouterHeaders() {
    _headers["HTTP-Referer"] = "clawd_code";
    _headers["X-Title"] = "clawd_code";
  }

  // parse custom headers from env var (newline or semicolon separated)
  void addCustomHeadersFromEnv() {
    final env = Platform.environment;
    final customHeadersEnv = env["ANTHROPIC_CUSTOM_HEADERS"];

    if (customHeadersEnv == null || customHeadersEnv.isEmpty) return;

    final headerStrings = customHeadersEnv.split(RegExp(r"\n|\r\n"));

    for (final headerString in headerStrings) {
      if (headerString.trim().isEmpty) continue;

      // parse "Name: Value" format, split on first colon
      final colonIdx = headerString.indexOf(":");
      if (colonIdx == -1) continue;

      final name = headerString.substring(0, colonIdx).trim();
      final value = headerString.substring(colonIdx + 1).trim();

      if (name.isNotEmpty) {
        _headers[name] = value;
      }
    }
  }

  Map<String, String> build() {
    return Map.unmodifiable(_headers);
  }
}

// builds user and assistant message objects for the API
class MessageBuilder {
  // create a user message
  static Map<String, dynamic> createUserMessage(String content) {
    return {
      "role": "user",
      "content": content,
    };
  }

  // create a user message with mixed content (text + tool results)
  static Map<String, dynamic> createUserMessageWithContent(
    List<Map<String, dynamic>> contentBlocks,
  ) {
    return {
      "role": "user",
      "content": contentBlocks,
    };
  }

  // create assistant message with text content
  static Map<String, dynamic> createAssistantMessage(String content) {
    return {
      "role": "assistant",
      "content": [
        {
          "type": "text",
          "text": content,
        }
      ],
    };
  }

  // create assistant message with tool use
  static Map<String, dynamic> createAssistantMessageWithToolUse(
    String toolId,
    String toolName,
    Map<String, dynamic> toolInput,
  ) {
    return {
      "role": "assistant",
      "content": [
        {
          "type": "tool_use",
          "id": toolId,
          "name": toolName,
          "input": toolInput,
        }
      ],
    };
  }

  // add tool result to existing user message
  static Map<String, dynamic> createToolResultContent(
    String toolUseId,
    String content,
  ) {
    return {
      "type": "tool_result",
      "tool_use_id": toolUseId,
      "content": content,
    };
  }
}

// normalize message content for sending to API
List<Map<String, dynamic>> normalizeMessagesForApi(
  List<Map<String, dynamic>> messages,
) {
  // basic validation and normalization
  // in real implementation would handle various message formats
  return messages;
}

// normalize content from api response
dynamic normalizeContentFromApi(dynamic content) {
  if (content is! List) return content;

  // ensure all blocks have proper types
  return List.from(content);
}