import os
import re
import tempfile
import shutil
import git
from huggingface_hub import (
    create_repo,
    upload_folder,
    list_repo_files,
    # delete_file, # Not used
    Repository,
    whoami,
)
import logging
from pathlib import Path

# Configure logging
logging.basicConfig(level=logging.INFO)
logger = logging.getLogger(__name__)

# Function to parse markdown input
def parse_markdown(markdown_input):
    """Parse markdown input to extract space details and file structure."""
    space_info = {"repo_name_md": "", "owner_md": "", "files": []}
    current_file = None
    file_content = []
    in_file_content = False # Tracks if we are inside a ### File: block content
    in_code_block = False # Tracks if we are inside a ``` code block ```

    lines = markdown_input.strip().split("\n")
    for line_idx, line_content_orig in enumerate(lines):
        line_content_stripped = line_content_orig.strip()

        # Handle file content collection, especially for code blocks
        if in_file_content:
            if line_content_stripped.startswith("```"):
                if in_code_block: # Closing ```
                    file_content.append(line_content_orig) # Keep the closing backticks as part of content
                    in_code_block = False
                    # Don't immediately save here, let the next ### File or end of input handle it
                    # This allows for text after a code block but before the next file.
                else: # Opening ```
                    in_code_block = True
                    file_content.append(line_content_orig)
            elif in_code_block: # Inside a code block
                file_content.append(line_content_orig)
            elif not in_code_block: # Plain text line within ### File: block but outside ```
                # Check if this line is a new file marker, if so, current file ends.
                if line_content_stripped.startswith("### File:") or line_content_stripped.startswith("## File Structure") or line_content_stripped.startswith("# Space:"):
                    if current_file and file_content:
                        space_info["files"].append({"path": current_file, "content": "\n".join(file_content)})
                    current_file = None # Reset
                    file_content = []
                    in_file_content = False # Current file ended
                    # Reprocess this line if it's a new file marker (will be handled by outer ifs)
                else: # Regular content line
                     file_content.append(line_content_orig)


        # Detect major structural elements
        if line_content_stripped.startswith("# Space:"):
            if current_file and file_content: # Save previous file if any
                space_info["files"].append({"path": current_file, "content": "\n".join(file_content)})
            full_space_name_md = line_content_stripped.replace("# Space:", "").strip()
            if "/" in full_space_name_md:
                space_info["owner_md"], space_info["repo_name_md"] = full_space_name_md.split("/", 1)
            else:
                space_info["repo_name_md"] = full_space_name_md
            current_file = None
            file_content = []
            in_file_content = False
            in_code_block = False

        elif line_content_stripped.startswith("## File Structure"):
            if current_file and file_content: # Save previous file if any
                space_info["files"].append({"path": current_file, "content": "\n".join(file_content)})
            current_file = None
            file_content = []
            in_file_content = False
            in_code_block = False
            continue # Just a section header

        elif line_content_stripped.startswith("### File:"):
            if current_file and file_content: # Save content of the previous file
                space_info["files"].append({"path": current_file, "content": "\n".join(file_content)})
            
            current_file = line_content_stripped.replace("### File:", "").strip()
            file_content = [] # Reset for new file
            in_file_content = True # Start collecting content lines for this file
            in_code_block = False # Reset code block state for new file

        # Note: 📄 and 📁 are ignored if ### File: is the primary mechanism as implemented.
        # If they are meant to define empty files, that logic would need to be added.
        # Current parser prioritizes ### File: sections for content.

    # Append the last file's content if any
    if current_file and file_content:
        space_info["files"].append({"path": current_file, "content": "\n".join(file_content)})
    
    space_info["files"] = [f for f in space_info["files"] if f.get("path")] # Filter out empty path entries
    return space_info


def _determine_repo_id(api_token, space_name_ui, owner_ui):
    """
    Determines the final owner and constructs the repo_id.
    space_name_ui should be just the name, not 'owner/name'.
    owner_ui is the value from the UI's owner field.
    Returns (repo_id, error_message)
    """
    if not space_name_ui:
        return None, "Error: Space Name cannot be empty."
    if "/" in space_name_ui: # User should not put slash in space name field
        return None, "Error: Space Name should not contain '/'. Please use the Owner field for the namespace."

    final_owner = owner_ui
    error_message = None

    if not final_owner:
        if not api_token:
            return None, "Error: API token is required to automatically determine owner when Owner field is empty."
        try:
            user_info = whoami(token=api_token)
            if user_info and 'name' in user_info:
                final_owner = user_info['name']
                logger.info(f"Determined owner: {final_owner} from API token.")
            else:
                logger.error(f"whoami(token=...) returned: {user_info} - 'name' field missing or user_info is None.")
                error_message = "Error: Could not retrieve username from API token. Ensure token is valid and has 'Read profile' permissions. Or, specify Owner manually."
        except Exception as e:
            logger.error(f"Error calling whoami for owner: {str(e)}")
            error_message = f"Error retrieving username from API token: {str(e)}. Please specify Owner manually."
        
        if error_message:
            return None, error_message

    if not final_owner: 
        return None, "Error: Owner could not be determined. Please provide an owner or ensure your API token is valid."

    return f"{final_owner}/{space_name_ui}", None

# Function to create and populate a Space
def create_space(api_token, space_name_ui, owner_ui, sdk_ui, markdown_input):
    """Create a Hugging Face Space and populate it with files from markdown input."""
    try:
        if not api_token:
            return "Error: Please provide a valid Hugging Face API token."

        repo_id, err = _determine_repo_id(api_token, space_name_ui, owner_ui)
        if err:
            return err
        
        space_info = parse_markdown(markdown_input)
        if not space_info["files"]:
            return "Error: No files found in the markdown input. Ensure '### File: path/to/file.ext' markers are used correctly with content."

        # Create temporary directory
        with tempfile.TemporaryDirectory() as temp_dir:
            repo_local_path = Path(temp_dir) / "repo_content_for_upload"
            repo_local_path.mkdir(exist_ok=True)

            # Write files to temporary directory
            for file_info in space_info["files"]:
                if not file_info.get("path"):
                    logger.warning(f"Skipping file with no path: {file_info}")
                    continue
                file_path_abs = repo_local_path / file_info["path"]
                file_path_abs.parent.mkdir(parents=True, exist_ok=True)
                with open(file_path_abs, "w", encoding="utf-8") as f:
                    f.write(file_info["content"])
                logger.info(f"Wrote file: {file_path_abs}")

            # Create repository on Hugging Face
            try:
                create_repo(
                    repo_id=repo_id,
                    token=api_token,
                    repo_type="space", # Correctly set
                    space_sdk=sdk_ui,
                    private=False,
                )
                logger.info(f"Created Space repo: {repo_id}")
            except Exception as e:
                err_str = str(e).lower()
                if "already exists" in err_str or "you already created this repo" in err_str or "exists" in err_str: # More robust check
                    logger.info(f"Space {repo_id} already exists, proceeding to upload/update files.")
                else:
                    return f"Error creating Space '{repo_id}': {str(e)}"
            
            # Push to Hugging Face Space
            upload_folder(
                repo_id=repo_id,
                folder_path=str(repo_local_path), # upload_folder expects string path
                path_in_repo=".",
                token=api_token,
                repo_type="space",  # ***** ADD THIS LINE *****
                commit_message=f"Initial Space setup of {repo_id} via Builder",
                # allow_patterns=["*.py", "*.md", "*.txt", "Dockerfile", ".gitattributes", "*.json", "*.yaml", "*.yml"], # Example: be more specific if needed
                # ignore_patterns=["*.git/*", ".*", "__pycache__/*"], # Example
            )
            logger.info(f"Uploaded files to Space: {repo_id}")
            return f"Successfully created/updated Space: [{repo_id}](https://huggingface.co/spaces/{repo_id})"

    except Exception as e:
        logger.exception(f"Error in create_space for {repo_id if 'repo_id' in locals() else 'unknown repo'}:") # Log full traceback
        return f"Error during Space creation/update: {str(e)}"

# Function to view Space files
def view_space_files(api_token, space_name_ui, owner_ui):
    """List files in a Hugging Face Space."""
    repo_id_for_error = f"{owner_ui}/{space_name_ui}" if owner_ui else space_name_ui
    try:
        if not api_token:
            return "Error: Please provide a valid Hugging Face API token."
        
        repo_id, err = _determine_repo_id(api_token, space_name_ui, owner_ui)
        if err:
            return err
        
        files = list_repo_files(repo_id=repo_id, token=api_token, repo_type="space") # Correctly set
        if files:
            return f"Files in `{repo_id}`:\n\n" + "\n".join([f"- `{f}`" for f in files])
        else:
            return f"No files found in the Space `{repo_id}`."
    except Exception as e:
        logger.exception(f"Error in view_space_files for {repo_id_for_error}:")
        return f"Error listing files for `{repo_id_for_error}`: {str(e)}"

# Function to update a Space file
def update_space_file(api_token, space_name_ui, owner_ui, file_path_in_repo, file_content, commit_message_ui):
    """Update a file in a Hugging Face Space with a commit."""
    repo_id_for_error = f"{owner_ui}/{space_name_ui}" if owner_ui else space_name_ui
    try:
        if not api_token:
            return "Error: Please provide a valid Hugging Face API token."

        repo_id, err = _determine_repo_id(api_token, space_name_ui, owner_ui)
        if err:
            return err
        
        if not file_path_in_repo:
            return "Error: File Path cannot be empty."
        if not commit_message_ui:
            commit_message_ui = f"Update {file_path_in_repo} via Space Builder"

        with tempfile.TemporaryDirectory() as temp_dir:
            repo_local_clone_path = Path(temp_dir) / "cloned_space_repo"
            
            cloned_repo = Repository(
                local_dir=str(repo_local_clone_path), # Repository expects string path
                clone_from=f"https://huggingface.co/spaces/{repo_id}", # Ensure this URL is correct
                repo_type="space", # Correctly set
                use_auth_token=api_token,
                git_user="Space Builder Bot", 
                git_email="space-builder@huggingface.co"
            )
            logger.info(f"Cloned Space {repo_id} to {repo_local_clone_path}")

            full_local_file_path = cloned_repo.local_dir / file_path_in_repo # Path object arithmetic
            full_local_file_path.parent.mkdir(parents=True, exist_ok=True)
            with open(full_local_file_path, "w", encoding="utf-8") as f:
                f.write(file_content)
            logger.info(f"Wrote updated file {file_path_in_repo} locally.")

            cloned_repo.push_to_hub(commit_message=commit_message_ui)
            logger.info(f"Pushed changes for {file_path_in_repo} to {repo_id}")
            
            return f"Successfully updated `{file_path_in_repo}` in Space [{repo_id}](https://huggingface.co/spaces/{repo_id})"

    except Exception as e:
        logger.exception(f"Error in update_space_file for {repo_id_for_error}:")
        return f"Error updating file for `{repo_id_for_error}`: {str(e)}"