feat: add google gemini 2.5 flash preview support

- add gemini as a new ai provider option
- implement gemini api integration with proper request/response handling
- add gemini-specific error messages and rate limiting
- update setup and config commands to support gemini
- add tests for gemini integration
- bump version to 0.3.0

Author: diazgdev

CHANGELOG.md

@@ -5,6 +5,17 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [0.3.0] - 2025-01-06
+
+### Added
+- Support for Google Gemini 2.5 Flash Preview AI model
+- Gemini-specific error handling and messages
+- Integration tests for Gemini API
+
+### Changed
+- Updated provider selection in setup and config commands to be dynamic
+- Enhanced error messages to be provider-specific
+
 ## [0.2.2] - 2025-03-22
 
 ### Fixed

Gemfile.lock

@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    git_auto (0.2.1)
+    git_auto (0.2.2)
       clipboard (~> 1.3)
       colorize (~> 1.1)
       http (~> 5.1)

README.md

@@ -17,6 +17,7 @@ GitAuto is a Ruby gem that streamlines your git workflow by automatically genera
 - 🤖 **AI Providers**: Supports multiple AI providers:
   - OpenAI (GPT-4o, GPT-4o mini)
   - Anthropic (Claude 3.5 Sonnet, Claude 3.5 Haiku)
+  - Google (Gemini 2.5 Flash)
 - 🔒 **Secure Storage**: Your API keys are encrypted using AES-256-CBC and stored securely
 
 ## Requirements ⚙️
@@ -26,6 +27,7 @@ GitAuto is a Ruby gem that streamlines your git workflow by automatically genera
 - 🎟️ One magical ingredient: an API key! Choose your AI companion:
   - 🔑 OpenAI API key ([Get one here](https://platform.openai.com/api-keys))
   - 🗝️ Anthropic API key ([Get one here](https://console.anthropic.com/))
+  - 🌟 Google Gemini API key ([Get one here](https://makersuite.google.com/app/apikey))
 
 That's it! Say goodbye to "misc fixes" and hello to commits that actually tell a story. Your future self will thank you! 🎩✨
 
@@ -108,8 +110,9 @@ git-auto commit
 
 Here's what we're planning for future releases:
 
-- 🤖 Support for Google Gemini AI
 - 📝 Automatic PR description generation
+- 🎯 Custom commit message templates
+- 🔄 Integration with Git hooks
 - More exciting features coming soon!
 
 ## Contributing 🤝

lib/git_auto/commands/config_command.rb

@@ -65,6 +65,9 @@ def set_setting(key, value)
         when "claude_api_key"
           @credential_store.store_api_key(value, "claude")
           puts "✓ Claude API key updated".green
+        when "gemini_api_key"
+          @credential_store.store_api_key(value, "gemini")
+          puts "✓ Gemini API key updated".green
         else
           @settings.set(key.to_sym, value)
           puts "✓ Setting '#{key}' updated to '#{value}'".green
@@ -122,10 +125,12 @@ def display_configuration
       end
 
       def configure_ai_provider
-        provider = @prompt.select("Choose AI provider:", {
-                                    "OpenAI (GPT-4, GPT-3.5 Turbo)" => "openai",
-                                    "Anthropic (Claude 3.5 Sonnet, Claude 3.5 Haiku)" => "claude"
-                                  })
+        # Use the supported providers from settings
+        provider_choices = Config::Settings::SUPPORTED_PROVIDERS.map do |key, info|
+          { name: info[:name], value: key }
+        end
+
+        provider = @prompt.select("Choose AI provider:", provider_choices)
 
         @settings.save(ai_provider: provider)
         puts "✓ AI provider updated to #{provider}".green

lib/git_auto/config/settings.rb

@@ -25,6 +25,12 @@ class Error < StandardError; end
             "GPT-4o" => "gpt-4o",
             "GPT-4o mini" => "gpt-4o-mini"
           }
+        },
+        "gemini" => {
+          name: "Google (Gemini 2.5 Flash)",
+          models: {
+            "Gemini 2.5 Flash Preview" => "gemini-2.5-flash-preview-05-20"
+          }
         }
       }.freeze
 

lib/git_auto/services/ai_service.rb

@@ -14,6 +14,7 @@ class RateLimitError < GitAuto::Errors::RateLimitError; end
 
       OPENAI_API_URL = "https://api.openai.com/v1/chat/completions"
       CLAUDE_API_URL = "https://api.anthropic.com/v1/messages"
+      GEMINI_API_URL = "https://generativelanguage.googleapis.com/v1beta/models"
       MAX_DIFF_SIZE = 10_000
       MAX_RETRIES = 3
       BACKOFF_BASE = 2
@@ -25,10 +26,10 @@ def reset_temperature
       end
 
       TEMPERATURE_VARIATIONS = [
-        { openai: 0.7, claude: 0.7 },
-        { openai: 0.8, claude: 0.8 },
-        { openai: 0.9, claude: 0.9 },
-        { openai: 1.0, claude: 1.0 }
+        { openai: 0.7, claude: 0.7, gemini: 0.7 },
+        { openai: 0.8, claude: 0.8, gemini: 0.8 },
+        { openai: 0.9, claude: 0.9, gemini: 0.9 },
+        { openai: 1.0, claude: 1.0, gemini: 1.0 }
       ].freeze
 
       def initialize(settings)
@@ -169,6 +170,8 @@ def generate_commit_message(diff, style: :conventional, scope: nil)
             generate_openai_commit_message(diff, style, scope)
           when "claude"
             generate_claude_commit_message(diff, style, scope)
+          when "gemini"
+            generate_gemini_commit_message(diff, style, scope)
           else
             raise GitAuto::Errors::InvalidProviderError, "Invalid AI provider specified"
           end
@@ -192,8 +195,7 @@ def add_suggestion(message)
       def previous_suggestions_prompt
         return "" if @previous_suggestions.empty?
 
-        "\nPrevious suggestions that you MUST NOT repeat:\n" +
-          @previous_suggestions.map { |s| "- #{s}" }.join("\n")
+        "\nPrevious suggestions that you MUST NOT repeat:\n#{@previous_suggestions.map { |s| "- #{s}" }.join("\n")}"
       end
 
       def generate_openai_commit_message(diff, style, scope = nil, retry_attempt = nil)
@@ -388,6 +390,110 @@ def generate_claude_commit_message(diff, style, scope = nil, retry_attempt = nil
         add_suggestion(message)
       end
 
+      def generate_gemini_commit_message(diff, style, scope = nil, retry_attempt = nil)
+        api_key = @credential_store.get_api_key("gemini")
+        raise APIKeyError, "Gemini API key is not set. Please set it using `git_auto config`" unless api_key
+
+        # Only use temperature variations for retries
+        temperature = retry_attempt ? get_temperature(retry_attempt) : TEMPERATURE_VARIATIONS[0][:gemini]
+        commit_types = ["feat", "fix", "docs", "style", "refactor", "test", "chore", "perf", "ci", "build",
+                        "revert"].join("|")
+
+        system_message = case style.to_s
+                         when "minimal"
+                           "You are a commit message generator that MUST follow the minimal commit format: <type>: <description>\n" \
+                           "Valid types are: #{commit_types}\n" \
+                           "Rules:\n" \
+                           "1. ALWAYS start with a type from the list above\n" \
+                           "2. NEVER include a scope\n" \
+                           "3. Keep the message under 72 characters\n" \
+                           "4. ALWAYS use lowercase - this is mandatory\n" \
+                           "5. Use present tense\n" \
+                           "6. Be descriptive but concise\n" \
+                           "7. Do not include a period at the end"
+                         when "conventional"
+                           "You are a commit message generator that MUST follow these rules EXACTLY:\n" \
+                           "1. ONLY output a single line containing the commit message\n" \
+                           "2. Use format: <type>(<scope>): <description>\n" \
+                           "3. Valid types are: #{commit_types}\n" \
+                           "4. Keep under 72 characters\n" \
+                           "5. ALWAYS use lowercase - this is mandatory\n" \
+                           "6. Use present tense\n" \
+                           "7. Be descriptive but concise\n" \
+                           "8. No period at the end\n" \
+                           "9. NO explanations or additional text\n" \
+                           "10. NO markdown formatting"
+                         when "detailed"
+                           "You are a commit message generator that MUST follow this format EXACTLY:\n" \
+                           "<summary line>\n" \
+                           "\n" \
+                           "<detailed description>\n" \
+                           "\n" \
+                           "Rules:\n" \
+                           "1. First line is a summary under 72 characters\n" \
+                           "2. ALWAYS use lowercase - this is mandatory\n" \
+                           "3. ALWAYS include a blank line after the summary\n" \
+                           "4. ALWAYS include a detailed description explaining:\n" \
+                           "   - What changes were made\n" \
+                           "   - Why the changes were necessary\n" \
+                           "   - Any technical details worth noting\n" \
+                           "5. Use bullet points for multiple changes\n" \
+                           "6. Use present tense\n" \
+                           "7. You can use periods in the detailed description\n" \
+                           "8. NO explanations or additional text\n" \
+                           "9. NO markdown formatting"
+                         else
+                           "You are an expert in writing clear and concise git commit messages.\n" \
+                           "Rules:\n" \
+                           "1. Keep the message under 72 characters\n" \
+                           "2. ALWAYS use lowercase - this is mandatory\n" \
+                           "3. Use present tense\n" \
+                           "4. Be descriptive but concise\n" \
+                           "5. Do not include a period at the end"
+                         end
+
+        user_message = if scope
+                         "Generate a conventional commit message with scope '#{scope}' for this diff:\n\n#{diff}"
+                       else
+                         "Generate a #{style} commit message for this diff:\n\n#{diff}"
+                       end
+
+        model = @settings.get(:ai_model)
+        url = "#{GEMINI_API_URL}/#{model}:generateContent?key=#{api_key}"
+
+        payload = {
+          contents: [
+            {
+              parts: [
+                {
+                  text: "#{system_message}\n\n#{user_message}"
+                }
+              ]
+            }
+          ],
+          generationConfig: {
+            temperature: temperature,
+            topK: 40,
+            topP: 0.95,
+            candidateCount: 1,
+            maxOutputTokens: 1024
+          }
+        }
+
+        log_api_request("gemini", payload, temperature) if @debug_mode
+
+        response = HTTP.headers({
+                                  "Content-Type" => "application/json"
+                                }).post(url, json: payload)
+
+        log_api_response(response.body) if @debug_mode
+
+        message = handle_response(response)
+        message = message.downcase.strip
+        message = message.sub(/\.$/, "") # Remove trailing period if present
+        add_suggestion(message)
+      end
+
       def style_description(style, scope)
         case style
         when :conventional, "conventional"
@@ -436,6 +542,21 @@ def handle_response(response)
               raise Error, "No valid commit message found in response" if commit_message.nil?
               commit_message.strip
             end
+
+          when "gemini"
+            content = json.dig("candidates", 0, "content", "parts", 0, "text")
+            raise Error, "No message content in response" if content.nil? || content.empty?
+
+            # For detailed style, keep the full message
+            if @settings.get(:commit_style) == "detailed"
+              content.strip
+            else
+              # Clean up the response and extract just the commit message
+              lines = content.strip.split("\n")
+              # Find the first line that looks like a commit message
+              commit_line = lines.find { |line| line.match(/^(feat|fix|docs|style|refactor|test|chore|perf|ci|build|revert)/) }
+              commit_line || lines.first.strip
+            end
           end
         when 401
           raise APIKeyError, "Invalid API key" unless ENV["RACK_ENV"] == "test"
@@ -447,8 +568,27 @@ def handle_response(response)
 
           "test commit message"
 
+        when 403
+          # Gemini-specific error for invalid API key
+          provider = @settings.get(:ai_provider)
+          if provider == "gemini"
+            raise APIKeyError, "Invalid Gemini API key. Please check your API key at https://makersuite.google.com/app/apikey"
+          else
+            raise APIKeyError, "Access forbidden. Please check your API key."
+          end
+
         when 429
-          raise RateLimitError, "Rate limit exceeded"
+          provider = @settings.get(:ai_provider)
+          case provider
+          when "gemini"
+            raise RateLimitError, "Gemini API rate limit exceeded. Please wait a moment and try again."
+          when "openai"
+            raise RateLimitError, "OpenAI API rate limit exceeded. Please try again later."
+          when "claude"
+            raise RateLimitError, "Claude API rate limit exceeded. Please try again later."
+          else
+            raise RateLimitError, "Rate limit exceeded"
+          end
         else
           raise Error, "API request failed with status #{response.code}: #{response.body}"
         end

lib/git_auto/version.rb

@@ -1,5 +1,5 @@
 # frozen_string_literal: true
 
 module GitAuto
-  VERSION = "0.2.2"
+  VERSION = "0.3.0"
 end

spec/git_auto/services/ai_service_gemini_spec.rb

@@ -0,0 +1,78 @@
+# frozen_string_literal: true
+
+require "spec_helper"
+
+RSpec.describe GitAuto::Services::AIService do
+  let(:settings) { instance_double(GitAuto::Config::Settings) }
+  let(:credential_store) { instance_double(GitAuto::Config::CredentialStore) }
+  let(:service) { described_class.new(settings) }
+  let(:diff) { "diff --git a/file.rb b/file.rb\n+puts 'Hello World'" }
+
+  before do
+    allow(GitAuto::Config::CredentialStore).to receive(:new).and_return(credential_store)
+    allow(GitAuto::Services::HistoryService).to receive(:new).and_return(
+      instance_double(GitAuto::Services::HistoryService)
+    )
+    allow(settings).to receive(:get).with(:ai_provider).and_return("gemini")
+    allow(settings).to receive(:get).with(:ai_model).and_return("gemini-2.5-flash")
+    allow(settings).to receive(:get).with(:commit_style).and_return("conventional")
+    allow(settings).to receive(:set)
+  end
+
+  describe "Gemini integration" do
+    context "with valid API key" do
+      before do
+        allow(credential_store).to receive(:get_api_key).with("gemini").and_return("test-api-key")
+      end
+
+      it "generates commit message using Gemini API" do
+        stub_request(:post, %r{https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash:generateContent})
+          .to_return(
+            status: 200,
+            body: {
+              candidates: [
+                {
+                  content: {
+                    parts: [
+                      { text: "feat: add hello world output" }
+                    ]
+                  }
+                }
+              ]
+            }.to_json,
+            headers: { "Content-Type" => "application/json" }
+          )
+
+        message = service.generate_commit_message(diff, style: :conventional)
+        expect(message).to eq("feat: add hello world output")
+      end
+
+      it "handles Gemini API errors gracefully" do
+        stub_request(:post, %r{https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash:generateContent})
+          .to_return(status: 403, body: { error: { message: "Invalid API key" } }.to_json)
+
+        expect { service.generate_commit_message(diff) }
+          .to raise_error(GitAuto::Services::AIService::APIKeyError, /Invalid Gemini API key/)
+      end
+
+      it "handles rate limiting" do
+        stub_request(:post, %r{https://generativelanguage.googleapis.com/v1beta/models/gemini-2.5-flash:generateContent})
+          .to_return(status: 429, body: { error: { message: "Rate limit exceeded" } }.to_json)
+
+        expect { service.generate_commit_message(diff) }
+          .to raise_error(GitAuto::Services::AIService::RateLimitError, /Gemini API rate limit exceeded/)
+      end
+    end
+
+    context "with missing API key" do
+      before do
+        allow(credential_store).to receive(:get_api_key).with("gemini").and_return(nil)
+      end
+
+      it "raises API key error" do
+        expect { service.generate_commit_message(diff) }
+          .to raise_error(GitAuto::Services::AIService::APIKeyError, /Gemini API key is not set/)
+      end
+    end
+  end
+end