Auto generate git commit message with ollama

git-auto-commit

#!/usr/bin/env bash
#
# git-auto-commit - Auto-generate commit messages using local LLM via Ollama
#
# Usage: git-auto-commit [options]
# Options:
#   -m, --model MODEL    Model to use (default: qwen2.5:3b)
#   --no-push            Skip auto-push after commit
#   -n, --no-author      Don't add AI co-author
#   -d, --dry-run        Show message without committing
#   -h, --help           Show this help
#
# By default, this script will:
#   - Auto-stage all changes (git add -A)
#   - Auto-push after commit
#
# Supported models (via Ollama):
#   - qwen2.5:3b (fast, recommended)
#   - qwen2.5:7b (better quality)
#   - gemma2:2b (very fast)
#   - gemma2:9b (better quality)
#   - llama3.2:3b (fast)
#   - mistral:7b (balanced)
#
# Requirements:
#   - Ollama running locally (ollama serve)
#   - curl, jq
#

set -e

# Colors
RED='\033[0;31m'
GREEN='\033[0;32m'
YELLOW='\033[1;33m'
BLUE='\033[0;34m'
NC='\033[0m'

# Default settings
MODEL="${GIT_COMMIT_MODEL:-qwen2.5:3b}"
OLLAMA_HOST="${OLLAMA_HOST:-http://localhost:11434}"
PUSH_AFTER=true
ADD_AI_AUTHOR=true
DRY_RUN=false

print_status() { echo -e "${GREEN}✓${NC} $1"; }
print_info() { echo -e "${BLUE}ℹ${NC} $1"; }
print_warning() { echo -e "${YELLOW}⚠${NC} $1"; }
print_error() { echo -e "${RED}✗${NC} $1"; }

show_help() {
    head -28 "$0" | tail -26 | sed 's/^#//' | sed 's/^ //'
    exit 0
}

# Parse arguments
while [[ $# -gt 0 ]]; do
    case $1 in
        -m|--model)
            MODEL="$2"
            shift 2
            ;;
        --no-push)
            PUSH_AFTER=false
            shift
            ;;
        -n|--no-author)
            ADD_AI_AUTHOR=false
            shift
            ;;
        -d|--dry-run)
            DRY_RUN=true
            shift
            ;;
        -h|--help)
            show_help
            ;;
        *)
            print_error "Unknown option: $1"
            show_help
            ;;
    esac
done

# Check dependencies
check_deps() {
    local missing=()
    command -v curl >/dev/null || missing+=("curl")
    command -v jq >/dev/null || missing+=("jq")
    command -v git >/dev/null || missing+=("git")

    if [[ ${#missing[@]} -gt 0 ]]; then
        print_error "Missing dependencies: ${missing[*]}"
        exit 1
    fi
}

# Check if Ollama is running
check_ollama() {
    if ! curl -s "${OLLAMA_HOST}/api/tags" >/dev/null 2>&1; then
        print_error "Ollama is not running at ${OLLAMA_HOST}"
        print_info "Start it with: ollama serve"
        exit 1
    fi
}

# Auto-stage and get diff
get_staged_diff() {
    # Auto-stage all changes
    print_info "Auto-staging changes..."
    git add -A

    local diff
    diff=$(git diff --cached --stat 2>/dev/null)

    if [[ -z "$diff" ]]; then
        print_warning "No changes to commit"
        exit 0
    fi

    # Get detailed diff (truncate if too large for speed)
    local full_diff
    full_diff=$(git diff --cached 2>/dev/null | head -500)

    echo "$full_diff"
}

# Generate commit message using Ollama
generate_commit_message() {
    local diff="$1"

    local prompt="Generate a concise git commit message for these changes.

Rules:
- Use conventional commit format: type(scope): description
- Types: feat, fix, refactor, docs, style, test, chore
- Keep the first line under 72 characters
- Be specific but brief
- No quotes around the message

Changes:
$diff

Commit message:"

    # Use Ollama's generate API (faster than chat for simple tasks)
    local response
    response=$(curl -s "${OLLAMA_HOST}/api/generate" \
        -H "Content-Type: application/json" \
        -d "$(jq -n --arg model "$MODEL" --arg prompt "$prompt" '{
            model: $model,
            prompt: $prompt,
            stream: false,
            options: {
                temperature: 0.3,
                num_predict: 100
            }
        }')" 2>/dev/null)

    if [[ -z "$response" ]]; then
        print_error "Failed to get response from Ollama"
        exit 1
    fi

    # Extract the response text
    local message
    message=$(echo "$response" | jq -r '.response // empty' | head -1 | sed 's/^[[:space:]]*//' | sed 's/[[:space:]]*$//')

    # Clean up the message (remove quotes if present)
    message=$(echo "$message" | sed 's/^["'"'"']//; s/["'"'"']$//')

    # Fallback if empty
    if [[ -z "$message" ]]; then
        message="chore: update files"
    fi

    echo "$message"
}

# Main
main() {
    check_deps
    check_ollama

    print_info "Using model: ${MODEL}"

    # Auto-stage and get changes
    local diff
    diff=$(get_staged_diff)

    # Show what's staged
    echo -e "${BLUE}Changes to commit:${NC}"
    git diff --cached --stat | head -20
    echo ""

    # Generate commit message
    print_info "Generating commit message..."
    local message
    message=$(generate_commit_message "$diff")

    echo -e "${GREEN}Generated message:${NC} $message"
    echo ""

    if $DRY_RUN; then
        print_info "Dry run - not committing"
        exit 0
    fi

    # Build commit command
    local commit_args=(-m "$message")

    # Add AI co-author
    if $ADD_AI_AUTHOR; then
        commit_args+=(-m "Co-Authored-By: Claude <claude@anthropic.com>")
    fi

    # Commit
    if git commit "${commit_args[@]}"; then
        print_status "Committed successfully!"
    else
        print_error "Commit failed"
        exit 1
    fi

    # Push if requested
    if $PUSH_AFTER; then
        print_info "Pushing to remote..."
        if git push; then
            print_status "Pushed successfully!"
        else
            print_warning "Push failed - you may need to set upstream"
        fi
    fi
}

main "$@"