#!/bin/bash
# Create a git worktree for feature isolation
# Usage: worktree-create.sh <feature-name>

set -e

FEATURE_NAME="$1"

if [ -z "$FEATURE_NAME" ]; then
    echo "Error: Feature name required"
    echo "Usage: worktree-create.sh <feature-name>"
    exit 1
fi

# Get project root from current working directory (where Claude Code is running)
# Note: This script is called from ${CLAUDE_PLUGIN_ROOT}/scripts/ but operates on the project
PROJECT_ROOT="$(pwd)"
PROJECT_NAME=$(basename "$PROJECT_ROOT")

# Define paths
BRANCH_NAME="feature/ab-${FEATURE_NAME}"
WORKTREES_DIR="$(dirname "$PROJECT_ROOT")/ab-worktrees"
WORKTREE_PATH="${WORKTREES_DIR}/${PROJECT_NAME}-${FEATURE_NAME}"

echo "========================================"
echo "  Creating Git Worktree"
echo "========================================"
echo ""
echo "Feature: $FEATURE_NAME"
echo "Branch:  $BRANCH_NAME"
echo "Path:    $WORKTREE_PATH"
echo ""

# Check if we're in a git repository
if ! git -C "$PROJECT_ROOT" rev-parse --git-dir > /dev/null 2>&1; then
    echo "Error: Not a git repository"
    exit 1
fi

# Check for uncommitted changes
if ! git -C "$PROJECT_ROOT" diff-index --quiet HEAD -- 2>/dev/null; then
    echo "Warning: You have uncommitted changes in the main repository"
    echo ""
fi

# Create worktrees directory if needed
mkdir -p "$WORKTREES_DIR"

# Create branch if it doesn't exist
cd "$PROJECT_ROOT"
if git show-ref --verify --quiet "refs/heads/${BRANCH_NAME}"; then
    echo "Branch already exists: ${BRANCH_NAME}"
else
    echo "Creating branch: ${BRANCH_NAME}"
    git branch "${BRANCH_NAME}"
fi

# Check if worktree already exists
if [ -d "$WORKTREE_PATH" ]; then
    echo "Error: Worktree directory already exists: $WORKTREE_PATH"
    echo "Use 'git worktree remove' to clean up first, or choose a different name"
    exit 1
fi

# Create worktree
echo "Creating worktree..."
git worktree add "$WORKTREE_PATH" "$BRANCH_NAME"

# Create symlink to .auto-build-data/ from main repo
# This ensures specs, plans, and status are shared across worktrees
if [ -d "$PROJECT_ROOT/.auto-build-data" ]; then
    echo "Creating symlink to .auto-build-data/..."
    ln -s "$PROJECT_ROOT/.auto-build-data" "$WORKTREE_PATH/.auto-build-data"
fi

# Also symlink .claude/rules/ for memory access
if [ -d "$PROJECT_ROOT/.claude/rules" ]; then
    mkdir -p "$WORKTREE_PATH/.claude"
    ln -s "$PROJECT_ROOT/.claude/rules" "$WORKTREE_PATH/.claude/rules"
fi

# Update registry
REGISTRY_FILE="$PROJECT_ROOT/.auto-build-data/worktrees/worktree-registry.json"
TIMESTAMP=$(date -u +"%Y-%m-%dT%H:%M:%SZ")

if [ -f "$REGISTRY_FILE" ]; then
    # Add to existing registry using jq if available, otherwise use simple append
    if command -v jq &> /dev/null; then
        TEMP_FILE=$(mktemp)
        jq --arg name "$FEATURE_NAME" \
           --arg branch "$BRANCH_NAME" \
           --arg path "$WORKTREE_PATH" \
           --arg created "$TIMESTAMP" \
           '.worktrees += [{
             "name": $name,
             "branch": $branch,
             "path": $path,
             "created": $created,
             "status": "active"
           }]' "$REGISTRY_FILE" > "$TEMP_FILE" && mv "$TEMP_FILE" "$REGISTRY_FILE"
    else
        # Fallback: Just note the worktree was created
        echo "Note: Install jq for automatic registry updates"
    fi
fi

echo ""
echo "========================================"
echo "  Worktree Created Successfully"
echo "========================================"
echo ""
echo "To work in this worktree:"
echo "  cd $WORKTREE_PATH"
echo ""
echo "To return to main project:"
echo "  cd $PROJECT_ROOT"
echo ""
echo "When done with the feature:"
echo "  /ab:worktree cleanup $FEATURE_NAME"
echo ""

# Output for script parsing
echo "WORKTREE_CREATED=$WORKTREE_PATH"
echo "BRANCH=$BRANCH_NAME"