#!/bin/bash
set -euo pipefail

# Create a git worktree for issue work or PR review
#
# Usage:
#   ./create-worktree.sh issue <issue-number>
#   ./create-worktree.sh review <pr-number> <branch-name>
#
# Returns: Absolute path to created worktree (stdout)

MODE="$1"
REPO_PATH=$(git rev-parse --show-toplevel 2>/dev/null || pwd)
REPO_NAME=$(basename "$REPO_PATH")
WORKTREES_DIR="${REPO_PATH}/../worktrees"

# Ensure worktrees directory exists
mkdir -p "$WORKTREES_DIR"

# Fetch latest from origin
cd "$REPO_PATH"
git fetch origin >/dev/null 2>&1

case "$MODE" in
  issue)
    ISSUE_NUMBER="$2"
    WORKTREE_NAME="${REPO_NAME}-issue-${ISSUE_NUMBER}"
    WORKTREE_PATH="${WORKTREES_DIR}/${WORKTREE_NAME}"

    # Get issue title for branch name (tea issues output has title on line 2: "  # #1 Title here")
    ISSUE_TITLE=$(tea issues "$ISSUE_NUMBER" 2>/dev/null | sed -n '2p' | sed 's/.*#[0-9]* //' | xargs || echo "untitled")

    # Create safe branch name
    BRANCH_NAME="issue-${ISSUE_NUMBER}-$(echo "$ISSUE_TITLE" | tr '[:upper:]' '[:lower:]' | tr ' ' '-' | tr -cd '[:alnum:]-' | cut -c1-50)"

    # Remove worktree if it already exists
    if [ -d "$WORKTREE_PATH" ]; then
      git worktree remove "$WORKTREE_PATH" --force 2>/dev/null || true
    fi

    # Delete branch if it exists
    git branch -D "$BRANCH_NAME" 2>/dev/null || true

    # Create worktree with new branch from main
    git worktree add "$WORKTREE_PATH" -b "$BRANCH_NAME" origin/main >/dev/null 2>&1

    echo "$WORKTREE_PATH"
    ;;

  review)
    PR_NUMBER="$2"
    BRANCH_NAME="$3"
    WORKTREE_NAME="${REPO_NAME}-review-${PR_NUMBER}"
    WORKTREE_PATH="${WORKTREES_DIR}/${WORKTREE_NAME}"

    # Remove worktree if it already exists
    if [ -d "$WORKTREE_PATH" ]; then
      git worktree remove "$WORKTREE_PATH" --force 2>/dev/null || true
    fi

    # Create worktree from existing branch
    git worktree add "$WORKTREE_PATH" "origin/${BRANCH_NAME}" >/dev/null 2>&1

    echo "$WORKTREE_PATH"
    ;;

  *)
    echo "Error: Invalid mode '$MODE'. Use 'issue' or 'review'" >&2
    echo "Usage:" >&2
    echo "  $0 issue <issue-number>" >&2
    echo "  $0 review <pr-number> <branch-name>" >&2
    exit 1
    ;;
esac