#!/usr/bin/env bash
# ==============================================================================
# Diablo 2 Web - Git Worktree Helper for Multi-Session Parallel Issue Fixing
#
# Usage:
#   ./scripts/worktree.sh create <issue_id_or_name> [base_branch]
#   ./scripts/worktree.sh list
#   ./scripts/worktree.sh remove <issue_id_or_name>
#
# Examples:
#   ./scripts/worktree.sh create 42
#   ./scripts/worktree.sh create 43 main
#   ./scripts/worktree.sh list
#   ./scripts/worktree.sh remove 42
# ==============================================================================

set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
REPO_ROOT="$(git -C "$SCRIPT_DIR" rev-parse --show-toplevel)"
PARENT_DIR="$(dirname "$REPO_ROOT")"

PRIMARY_SOURCE="/usr/local/google/home/taodao/d2w-wg1-main"
if [[ ! -d "$PRIMARY_SOURCE" ]]; then
  PRIMARY_SOURCE="$REPO_ROOT"
fi

parse_target() {
  local input="$1"
  if [[ "$input" =~ ^[0-9]+$ ]]; then
    BRANCH="fix/issue-${input}"
    DIR_NAME="d2w-issue-${input}"
  elif [[ "$input" =~ ^fix/issue-([0-9]+)$ ]]; then
    BRANCH="$input"
    DIR_NAME="d2w-issue-${BASH_REMATCH[1]}"
  else
    BRANCH="$input"
    local sanitized
    sanitized="$(echo "$input" | tr '/' '-')"
    DIR_NAME="d2w-${sanitized}"
  fi
  TARGET_DIR="${PARENT_DIR}/${DIR_NAME}"
}

cmd_create() {
  local input="${1:-}"
  local base_branch="${2:-main}"

  if [[ -z "$input" ]]; then
    echo "Error: Issue ID or branch name is required."
    echo "Example: $0 create 42"
    exit 1
  fi

  parse_target "$input"

  echo "============================================================"
  echo ">>> Creating Worktree for Issue/Task: $input"
  echo "    Target Directory: $TARGET_DIR"
  echo "    Branch Name:      $BRANCH"
  echo "    Base Branch:      $base_branch"
  echo "============================================================"

  if [[ -d "$TARGET_DIR" ]]; then
    echo "Error: Directory '$TARGET_DIR' already exists!"
    exit 1
  fi

  # Check if branch exists
  if git -C "$REPO_ROOT" show-ref --verify --quiet "refs/heads/$BRANCH"; then
    echo "--> Branch '$BRANCH' already exists. Attaching to existing branch..."
    git -C "$REPO_ROOT" worktree add "$TARGET_DIR" "$BRANCH"
  else
    echo "--> Creating new branch '$BRANCH' from '$base_branch'..."
    git -C "$REPO_ROOT" worktree add "$TARGET_DIR" -b "$BRANCH" "$base_branch"
  fi

  echo "--> Symlinking node_modules from $PRIMARY_SOURCE..."
  if [[ -d "$PRIMARY_SOURCE/node_modules" ]]; then
    ln -s "$PRIMARY_SOURCE/node_modules" "$TARGET_DIR/node_modules"
  else
    echo "Warning: $PRIMARY_SOURCE/node_modules not found. You may need to run 'npm install'."
  fi

  echo "--> Symlinking samples/ assets..."
  mkdir -p "$TARGET_DIR/samples"
  if [[ -d "$PRIMARY_SOURCE/samples/d2-packs" ]]; then
    ln -s "$PRIMARY_SOURCE/samples/d2-packs" "$TARGET_DIR/samples/d2-packs"
  fi
  if [[ -L "$PRIMARY_SOURCE/samples/d2" ]]; then
    cp -P "$PRIMARY_SOURCE/samples/d2" "$TARGET_DIR/samples/d2" 2>/dev/null || true
  fi

  echo "--> Running smoke verification test in new worktree..."
  (
    cd "$TARGET_DIR"
    npx vitest run tests/save-schema.test.ts --reporter=basic
  )

  echo ""
  echo "============================================================"
  echo " Worktree created successfully!"
  echo "============================================================"
  echo "To start working in this session:"
  echo "  cd $TARGET_DIR"
  echo ""
  echo "To run tests in this worktree:"
  echo "  npm test"
  echo ""
  echo "To run Vite dev server (use a separate port):"
  echo "  npm run dev -- --port 5174"
  echo ""
  echo "When finished with this issue, you can clean it up via:"
  echo "  $0 remove $input"
  echo "============================================================"
}

cmd_list() {
  echo "Current active worktrees:"
  git -C "$REPO_ROOT" worktree list
}

cmd_remove() {
  local input="${1:-}"
  if [[ -z "$input" ]]; then
    echo "Error: Issue ID or branch name is required."
    echo "Example: $0 remove 42"
    exit 1
  fi

  parse_target "$input"

  if [[ ! -d "$TARGET_DIR" ]]; then
    echo "Warning: Directory '$TARGET_DIR' does not exist."
    git -C "$REPO_ROOT" worktree list
    return
  fi

  echo "Removing worktree at '$TARGET_DIR'..."
  # Remove symlinks first to be clean
  rm -f "$TARGET_DIR/node_modules" "$TARGET_DIR/samples/d2-packs" "$TARGET_DIR/samples/d2" 2>/dev/null || true
  git -C "$REPO_ROOT" worktree remove "$TARGET_DIR"
  echo "Worktree removed. Note: Git branch '$BRANCH' is preserved."
  echo "To delete the branch as well (if merged), run:"
  echo "  git branch -d $BRANCH"
}

case "${1:-}" in
  create)
    shift
    cmd_create "$@"
    ;;
  list)
    cmd_list
    ;;
  remove)
    shift
    cmd_remove "$@"
    ;;
  *)
    echo "Usage: $0 {create <id>|list|remove <id>}"
    exit 1
    ;;
esac