"""HuggingFace Hub push and project ZIP packaging.

Creates ZIP archives from extracted project files and pushes
projects to HuggingFace Spaces or model repos.
"""

from __future__ import annotations

import logging
import os
import re
import tempfile
import zipfile
from pathlib import Path
from typing import Any

from code.config.constants import MODEL_ID
from code.huggingface.dockerfile_gen import (
    detect_framework,
    is_js_project,
    scaffold_js_project,
)

logger = logging.getLogger(__name__)

# ─── Import-to-Package Mapping ──────────────────────────────────────────

IMPORT_TO_PACKAGE: dict[str, str] = {
    "gradio": "gradio>=4.0.0",
    "flask": "flask>=3.0.0",
    "django": "django>=4.2.0",
    "fastapi": "fastapi>=0.100.0",
    "uvicorn": "uvicorn>=0.23.0",
    "streamlit": "streamlit>=1.28.0",
    "matplotlib": "matplotlib>=3.8.0",
    "PIL": "Pillow>=10.0.0",
    "Pillow": "Pillow>=10.0.0",
    "numpy": "numpy>=1.24.0",
    "pandas": "pandas>=2.0.0",
    "scipy": "scipy>=1.11.0",
    "sklearn": "scikit-learn>=1.3.0",
    "scikit_learn": "scikit-learn>=1.3.0",
    "torch": "torch>=2.1.0",
    "tensorflow": "tensorflow>=2.14.0",
    "transformers": "transformers>=4.35.0",
    "requests": "requests>=2.31.0",
    "beautifulsoup4": "beautifulsoup4>=4.12.0",
    "bs4": "beautifulsoup4>=4.12.0",
    "selenium": "selenium>=4.15.0",
    "sqlalchemy": "sqlalchemy>=2.0.0",
    "pydantic": "pydantic>=2.0.0",
    "httpx": "httpx>=0.25.0",
    "aiohttp": "aiohttp>=3.9.0",
    "opencv": "opencv-python-headless>=4.8.0",
    "cv2": "opencv-python-headless>=4.8.0",
    "plotly": "plotly>=5.18.0",
    "seaborn": "seaborn>=0.13.0",
    "wordcloud": "wordcloud>=1.9.0",
    "networkx": "networkx>=3.2.0",
    "sympy": "sympy>=1.12",
    "Pillow": "Pillow>=10.0.0",
    "skimage": "scikit-image>=0.21.0",
    "soundfile": "soundfile>=0.12.0",
    "pydub": "pydub>=0.25.1",
    "moviepy": "moviepy>=1.0.3",
    "openpyxl": "openpyxl>=3.1.0",
    "xlsxwriter": "xlsxwriter>=3.1.0",
    "python-docx": "python-docx>=0.8.11",
    "docx": "python-docx>=0.8.11",
    "reportlab": "reportlab>=4.0.0",
    "jinja2": "jinja2>=3.1.0",
    "wtforms": "wtforms>=3.1.0",
    "flask_sqlalchemy": "flask-sqlalchemy>=3.1.0",
    "flask_login": "flask-login>=0.6.0",
    "flask_wtf": "flask-wtf>=1.2.0",
    "flask_cors": "flask-cors>=4.0.0",
}


def _scan_imports(code: str) -> list[str]:
    """Scan Python code for import statements and return package names."""
    packages = set()

    # Match: import xxx
    for m in re.finditer(r"^\s*import\s+([a-zA-Z_][\w.]*)", code, re.MULTILINE):
        top_level = m.group(1).split(".")[0]
        packages.add(top_level)

    # Match: from xxx import ...
    for m in re.finditer(r"^\s*from\s+([a-zA-Z_][\w.]*)", code, re.MULTILINE):
        top_level = m.group(1).split(".")[0]
        packages.add(top_level)

    return sorted(packages)


def generate_requirements(code: str) -> str:
    """Generate requirements.txt content from code by scanning imports.

    Returns a newline-separated string of pip package specs.
    """
    packages = _scan_imports(code)
    reqs: list[str] = []

    for pkg in packages:
        if pkg in IMPORT_TO_PACKAGE:
            req_spec = IMPORT_TO_PACKAGE[pkg]
            if req_spec not in reqs:
                reqs.append(req_spec)
        # Skip stdlib modules (os, sys, json, re, math, etc.)

    # Always include gradio for Gradio apps if not already
    if "import gradio" in code or "from gradio" in code:
        if "gradio" not in [r.split(">=")[0].split("[")[0] for r in reqs]:
            reqs.insert(0, "gradio>=4.0.0")

    return "\n".join(reqs) + "\n" if reqs else ""


def _find_entry_point(files: dict[str, str]) -> str:
    """Find the main entry point file for a project.

    Looks for app.py, main.py, or any Python file with a launcher pattern.
    """
    # Priority order for Python entry points
    candidates = ["app.py", "main.py", "index.py", "server.py", "run.py"]
    for c in candidates:
        if c in files:
            return c

    # Priority order for JS entry points
    js_candidates = ["index.js", "server.js", "src/index.js", "src/main.jsx", "src/main.tsx"]
    for c in js_candidates:
        if c in files:
            return c

    # Look for any .py file with if __name__ == "__main__" or .launch()
    for fname, content in files.items():
        if fname.endswith(".py"):
            if "__main__" in content or ".launch(" in content or "app.run(" in content:
                return fname

    # Fall back to first .py file
    for fname in files:
        if fname.endswith(".py"):
            return fname

    # Fall back to first file
    return next(iter(files), "app.py")


def _detect_sdk(files: dict[str, str], entry: str) -> str:
    """Auto-detect the best Space SDK from the project files."""
    all_code = "\n".join(files.values())

    if "import streamlit" in all_code or "from streamlit" in all_code:
        return "streamlit"
    if "import gradio" in all_code or "from gradio" in all_code:
        return "gradio"

    # JS/TS projects → Docker
    if is_js_project(files):
        return "docker"

    if any(f.endswith(".html") for f in files):
        return "static"
    if entry.endswith(".py"):
        return "gradio"  # Default Python to Gradio SDK

    return "static"


def create_project_zip(files: dict[str, str], project_name: str) -> str:
    """Create a ZIP file from extracted project files.

    Returns the path to the created ZIP file.
    """
    zip_dir = tempfile.mkdtemp(prefix="fullstack_project_")
    zip_path = os.path.join(zip_dir, f"{project_name}.zip")

    with zipfile.ZipFile(zip_path, "w", zipfile.ZIP_DEFLATED) as zf:
        for filepath, content in files.items():
            zf.writestr(f"{project_name}/{filepath}", content)

    return zip_path


def push_to_huggingface(
    files: dict[str, str],
    project_name: str,
    repo_name: str,
    hf_token: str,
    space_sdk: str = "static",
    is_space: bool = True,
) -> dict[str, Any]:
    """Push generated project to HuggingFace Hub.

    Creates the repo if it doesn't exist, writes all files,
    and adds README.md, Dockerfile, package.json, and requirements.txt as needed.
    """
    try:
        from huggingface_hub import HfApi, create_repo

        api = HfApi(token=hf_token)

        if "/" in repo_name:
            namespace, name = repo_name.split("/", 1)
        else:
            user_info = api.whoami()
            namespace = user_info["name"]
            name = repo_name
            repo_name = f"{namespace}/{name}"

        # Find entry point and auto-detect SDK
        entry_point = _find_entry_point(files)
        detected_sdk = _detect_sdk(files, entry_point)

        # Use detected SDK if user left it as "static" but project needs something else
        if space_sdk == "static" and detected_sdk != "static":
            space_sdk = detected_sdk

        # For JS projects, scaffold Docker support files
        if is_js_project(files) or space_sdk == "docker":
            framework = detect_framework(files)
            if framework == "static":
                # Single HTML file or simple JS — keep as static
                if any(f.endswith(".html") for f in files) and not is_js_project(files):
                    space_sdk = "static"
                else:
                    framework = "nodejs"
                    space_sdk = "docker"

            if space_sdk == "docker":
                files = scaffold_js_project(files, framework, project_name)

        try:
            if is_space:
                create_repo(
                    repo_id=repo_name,
                    repo_type="space",
                    space_sdk=space_sdk,
                    token=hf_token,
                    exist_ok=True,
                )
            else:
                create_repo(
                    repo_id=repo_name,
                    repo_type="model",
                    token=hf_token,
                    exist_ok=True,
                )
        except Exception as e:
            logger.warning("Repo creation warning: %s", e)

        with tempfile.TemporaryDirectory(prefix="hf_push_") as tmp_dir:
            # Write all project files
            for filepath, content in files.items():
                full_path = os.path.join(tmp_dir, filepath)
                os.makedirs(os.path.dirname(full_path), exist_ok=True)
                Path(full_path).write_text(content, encoding="utf-8")

            # Ensure the entry point is named app.py for HF Spaces (Python)
            if entry_point != "app.py" and entry_point.endswith(".py") and is_space and space_sdk in ("gradio", "streamlit"):
                src = os.path.join(tmp_dir, entry_point)
                dst = os.path.join(tmp_dir, "app.py")
                if os.path.exists(src) and not os.path.exists(dst):
                    import shutil
                    shutil.copy2(src, dst)

            # Determine app_file for README
            if space_sdk == "docker":
                app_file = "Dockerfile"
            elif space_sdk in ("gradio", "streamlit"):
                app_file = "app.py"
            elif space_sdk == "static":
                if "index.html" in files:
                    app_file = "index.html"
                elif any(f.endswith(".html") for f in files):
                    app_file = next(f for f in files if f.endswith(".html"))
                else:
                    app_file = entry_point
            else:
                app_file = entry_point

            # Add README.md if not present
            readme_path = os.path.join(tmp_dir, "README.md")
            if not os.path.exists(readme_path):
                readme_content = f"""---
title: {name}
emoji: 🚀
colorFrom: blue
colorTo: purple
sdk: {space_sdk}
app_file: {app_file}
pinned: false
---

# {name}

Generated by Fullstack Code Builder using {MODEL_ID}.
"""
                Path(readme_path).write_text(readme_content, encoding="utf-8")
            else:
                # Update app_file in existing README to match entry point
                existing = Path(readme_path).read_text(encoding="utf-8")
                if "app_file:" in existing:
                    existing = re.sub(
                        r"app_file:\s*\S+", f"app_file: {app_file}", existing
                    )
                if "sdk:" in existing:
                    existing = re.sub(
                        r"sdk:\s*\S+", f"sdk: {space_sdk}", existing
                    )
                Path(readme_path).write_text(existing, encoding="utf-8")

            # Add/merge requirements.txt for Python projects
            req_path = os.path.join(tmp_dir, "requirements.txt")
            has_python = any(f.endswith(".py") for f in files.keys())

            if has_python and space_sdk != "docker":
                # Scan all Python code for imports
                all_py_code = "\n".join(
                    content for fname, content in files.items()
                    if fname.endswith(".py")
                )
                auto_reqs = generate_requirements(all_py_code)

                if os.path.exists(req_path):
                    # Merge with existing requirements.txt
                    existing_reqs = Path(req_path).read_text(encoding="utf-8").strip()
                    merged = set()
                    for line in (existing_reqs + "\n" + auto_reqs).splitlines():
                        line = line.strip()
                        if line and not line.startswith("#"):
                            merged.add(line)

                    Path(req_path).write_text("\n".join(sorted(merged)) + "\n", encoding="utf-8")
                elif auto_reqs:
                    Path(req_path).write_text(auto_reqs, encoding="utf-8")
                else:
                    # Minimal requirements for Python Spaces
                    Path(req_path).write_text("gradio>=4.0.0\n", encoding="utf-8")

            api.upload_folder(
                folder_path=tmp_dir,
                repo_id=repo_name,
                repo_type="space" if is_space else "model",
                token=hf_token,
            )

        repo_url = f"https://huggingface.co/{repo_name}"
        if is_space:
            repo_url = f"https://huggingface.co/spaces/{repo_name}"

        return {
            "success": True,
            "url": repo_url,
            "repo_name": repo_name,
            "message": f"Successfully pushed to {repo_url}",
        }

    except Exception as exc:
        logger.exception("Failed to push to HuggingFace")
        return {
            "success": False,
            "url": "",
            "repo_name": repo_name,
            "message": f"Failed to push: {str(exc)}",
        }