import os
import re
import sys
import subprocess
import shutil
import platform
from common import get_git_root, find_submodule_paths, get_project_root

def remove_dependency(pkg_path=None):
 """
 Remove the specified submodule (if pkg_path is provided) or all submodules
 within the current Git repository.

 Args:
 pkg_path (str, optional): Relative path of the submodule to remove. If None, all submodules will be removed.

 Raises:
 FileNotFoundError: If the .gitmodules file is not found in the repository root.
 ValueError: If the provided pkg_path is not a valid submodule or is not within the current Git repository.
 """
 try:
 repo_root = get_git_root()
 submodule_paths_rel = find_submodule_paths(repo_root)
 submodule_paths_abs = [os.path.abspath(os.path.join(repo_root, rel_path)) for rel_path in submodule_paths_rel]

 if not submodule_paths_abs:
 print("No submodules found in the current repository.")
 return

 gitmodules_path = os.path.join(repo_root, '.gitmodules')

 # Keep track of removed submodule relative paths
 removed_submodule_paths = []

 if pkg_path:
 # Make pkg_path absolute based on the current working directory
 pkg_path_abs = os.path.abspath(os.path.join(repo_root, pkg_path))

 # Check if pkg_path is within the current Git repository
 if not pkg_path_abs.startswith(repo_root):
 print(f"Error: '{pkg_path}' is not within the current Git repository.")
 sys.exit(1)

 # Remove a single submodule
 if pkg_path_abs not in submodule_paths_abs:
 print(f"Error: '{pkg_path}' is not a valid submodule in the current repository.")
 sys.exit(1)

 # Verify that the provided pkg_path is a valid Git submodule
 submodule_git_file = os.path.join(pkg_path_abs, '.git')
 if not os.path.isfile(submodule_git_file):
 print(f"Error: '{pkg_path}' is not a valid Git submodule.")
 sys.exit(1)

 print(f"Removing submodule '{pkg_path}'...")
 subprocess.run(['git', 'submodule', 'deinit', '--force', pkg_path_abs])
 subprocess.run(['git', 'rm', '--cached', '-r', pkg_path_abs])
 shutil.rmtree(pkg_path_abs)

 # Calculate the relative path of the submodule from the repository root
 pkg_path_rel = os.path.relpath(pkg_path_abs, start=repo_root)

 # Add the removed submodule's relative path to the list
 removed_submodule_paths.append(pkg_path_rel)

 else:
 # Remove all submodules
 print("Removing all submodules...")
 for submodule_path in submodule_paths_abs:
 submodule_git_file = os.path.join(submodule_path, '.git')
 if not os.path.isfile(submodule_git_file):
 print(f"Error: '{submodule_path}' is not a valid Git submodule.")
 sys.exit(1)

 subprocess.run(['git', 'submodule', 'deinit', '--force', submodule_path])
 subprocess.run(['git', 'rm', '--cached', '-r', submodule_path])
 shutil.rmtree(submodule_path)

 # Add the removed submodule's relative path to the list
 removed_submodule_paths.append(os.path.relpath(submodule_path, start=repo_root))

 # Compute the relative path of the current Git repository to the top-level Git repository
 current_repo_to_top_level_rel = os.path.relpath(repo_root, start=get_project_root())

 # Iterate over the removed submodule relative paths
 for submodule_path_rel in removed_submodule_paths:

 # Compute the relative path of the submodule to the top-level Git repository
 submodule_to_top_level_rel = os.path.join(current_repo_to_top_level_rel, submodule_path_rel)

 # Compute the absolute path of the submodule directory in the top-level Git repository's .git/modules
 top_level_submodule_dir = os.path.join(get_project_root(), '.git', 'modules', submodule_to_top_level_rel)

 # Ensure the directory exists before attempting to delete it
 if os.path.isdir(top_level_submodule_dir):
 print(f"Deleting top-level submodule directory: {top_level_submodule_dir}")
 if platform.system() == 'Windows':
 subprocess.check_output(['cmd.exe', '/c', 'rmdir', '/s', '/q', top_level_submodule_dir])
 else:
 shutil.rmtree(top_level_submodule_dir)

 # Update .gitmodules content for all removed submodules
 with open(gitmodules_path, 'r') as f:
 content = f.read()

 for submodule_path_rel in removed_submodule_paths:
 pattern = r'^\[submodule\s+"{}"\](?:(?!^\[submodule\b).)*$'.format(submodule_path_rel)
 content = re.sub(pattern, '', content, flags=re.MULTILINE | re.DOTALL)

 with open(gitmodules_path, 'w') as f:
 print("Updating .gitmodules file in current git repository...")
 f.write(content)

 subprocess.run(['git', 'add', gitmodules_path])
 print("Removed submodule(s) successfully.")
 except Exception as e:
 print(f"Error: Failed to remove submodule(s): {e}")
 sys.exit(1)