#!/usr/bin/env python3
"""
Soleprint Build Tool

Builds the soleprint instance using modelgen for model generation.

Modes:
- dev: Uses symlinks for quick development (edit source, run from gen/)
- deploy: Copies everything for production deployment (no symlinks)

Usage:
    python build.py dev
    python build.py deploy --output /path/to/deploy/
    python build.py models

Examples:
    # Set up dev environment
    python build.py dev

    # Build for deployment
    python build.py deploy --output ../deploy/soleprint/

    # Only regenerate models
    python build.py models
"""

import argparse
import os
import shutil
import subprocess
import sys
from pathlib import Path

# SPR root is where this script lives
SPR_ROOT = Path(__file__).resolve().parent


def ensure_dir(path: Path):
    """Create directory if it doesn't exist."""
    path.mkdir(parents=True, exist_ok=True)


def create_symlink(source: Path, target: Path):
    """Create a symlink, removing existing if present."""
    if target.exists() or target.is_symlink():
        if target.is_symlink():
            target.unlink()
        elif target.is_dir():
            shutil.rmtree(target)
        else:
            target.unlink()

    # Make relative symlink
    rel_source = os.path.relpath(source, target.parent)
    target.symlink_to(rel_source)
    print(f"  Linked: {target.name} -> {rel_source}")


def copy_path(source: Path, target: Path):
    """Copy file or directory, resolving symlinks."""
    if target.exists():
        if target.is_dir():
            shutil.rmtree(target)
        else:
            target.unlink()

    if source.is_dir():
        shutil.copytree(source, target, symlinks=False)
        print(f"  Copied: {target.name}/ ({count_files(target)} files)")
    else:
        shutil.copy2(source, target)
        print(f"  Copied: {target.name}")


def count_files(path: Path) -> int:
    """Count files in directory recursively."""
    return sum(1 for _ in path.rglob("*") if _.is_file())


def generate_models(output_dir: Path):
    """Generate models using modelgen tool.

    Args:
        output_dir: Directory where models/pydantic/__init__.py will be created
    """
    config_path = SPR_ROOT / "config" / "soleprint.config.json"

    if not config_path.exists():
        print(f"Warning: Config not found at {config_path}")
        return False

    # Soleprint-specific: models go in models/pydantic/__init__.py
    models_file = output_dir / "models" / "pydantic" / "__init__.py"
    models_file.parent.mkdir(parents=True, exist_ok=True)

    # Run modelgen as subprocess
    cmd = [
        sys.executable,
        "-m",
        "station.tools.modelgen",
        "from-config",
        "--config",
        str(config_path),
        "--output",
        str(models_file),
        "--format",
        "pydantic",
    ]

    result = subprocess.run(cmd, cwd=SPR_ROOT)
    return result.returncode == 0


def build_dev(output_dir: Path):
    """
    Build for development using symlinks.

    Structure:
        gen/
        ├── main.py           -> ../hub/main.py
        ├── index.html        -> ../hub/index.html
        ├── requirements.txt  -> ../hub/requirements.txt
        ├── dataloader/       -> ../hub/dataloader/
        ├── artery/           -> ../artery/
        ├── atlas/            -> ../atlas/
        ├── station/          -> ../station/
        ├── data/             -> ../data/
        └── models/           # Generated
    """
    print(f"\n=== Building DEV environment ===")
    print(f"SPR root: {SPR_ROOT}")
    print(f"Output:   {output_dir}")

    ensure_dir(output_dir)

    # Hub files (symlinks)
    print("\nLinking hub files...")
    hub = SPR_ROOT / "hub"
    create_symlink(hub / "main.py", output_dir / "main.py")
    create_symlink(hub / "index.html", output_dir / "index.html")
    create_symlink(hub / "requirements.txt", output_dir / "requirements.txt")
    create_symlink(hub / "dataloader", output_dir / "dataloader")

    # System directories (symlinks)
    print("\nLinking systems...")
    for system in ["artery", "atlas", "station"]:
        source = SPR_ROOT / system
        if source.exists():
            create_symlink(source, output_dir / system)

    # Data directory (symlink)
    print("\nLinking data...")
    create_symlink(SPR_ROOT / "data", output_dir / "data")

    # Models (generated) - pass output_dir, modelgen adds models/pydantic
    print("\nGenerating models...")
    if not generate_models(output_dir):
        print("  Warning: Model generation failed, you may need to run it manually")

    print("\n✓ Dev build complete!")
    print(f"\nTo run:")
    print(f"  cd {output_dir}")
    print(f"  python3 -m venv .venv")
    print(f"  .venv/bin/pip install -r requirements.txt")
    print(f"  .venv/bin/python main.py")


def build_deploy(output_dir: Path):
    """
    Build for deployment by copying all files (no symlinks).
    """
    print(f"\n=== Building DEPLOY package ===")
    print(f"SPR root: {SPR_ROOT}")
    print(f"Output:   {output_dir}")

    if output_dir.exists():
        response = input(f"\nOutput directory exists. Overwrite? [y/N] ")
        if response.lower() != "y":
            print("Aborted.")
            return
        shutil.rmtree(output_dir)

    ensure_dir(output_dir)

    # Hub files (copy)
    print("\nCopying hub files...")
    hub = SPR_ROOT / "hub"
    copy_path(hub / "main.py", output_dir / "main.py")
    copy_path(hub / "index.html", output_dir / "index.html")
    copy_path(hub / "requirements.txt", output_dir / "requirements.txt")
    copy_path(hub / "dataloader", output_dir / "dataloader")

    # System directories (copy)
    print("\nCopying systems...")
    for system in ["artery", "atlas", "station"]:
        source = SPR_ROOT / system
        if source.exists():
            copy_path(source, output_dir / system)

    # Data directory (copy)
    print("\nCopying data...")
    copy_path(SPR_ROOT / "data", output_dir / "data")

    # Models (generate fresh) - pass output_dir, modelgen adds models/pydantic
    print("\nGenerating models...")
    if not generate_models(output_dir):
        # Fallback: copy from gen if exists
        existing = SPR_ROOT / "gen" / "models"
        if existing.exists():
            print("  Using existing models from gen/")
            copy_path(existing, output_dir / "models")

    # Copy schema.json for reference
    print("\nCopying schema...")
    copy_path(SPR_ROOT / "schema.json", output_dir / "schema.json")

    # Create run script
    run_script = output_dir / "run.sh"
    run_script.write_text("""#!/bin/bash
# Soleprint runner
cd "$(dirname "$0")"

if [ ! -d ".venv" ]; then
    echo "Creating virtual environment..."
    python3 -m venv .venv
    .venv/bin/pip install -r requirements.txt
fi

echo "Starting soleprint on http://localhost:12000"
.venv/bin/python main.py
""")
    run_script.chmod(0o755)
    print("  Created: run.sh")

    total_files = count_files(output_dir)
    print(f"\n✓ Deploy build complete! ({total_files} files)")
    print(f"\nTo run:")
    print(f"  cd {output_dir}")
    print(f"  ./run.sh")
    print(f"\nOr deploy to server:")
    print(f"  rsync -av {output_dir}/ server:/app/soleprint/")
    print(f"  ssh server 'cd /app/soleprint && ./run.sh'")


def build_models():
    """Only regenerate models."""
    print(f"\n=== Generating models only ===")

    output_dir = SPR_ROOT / "gen"
    ensure_dir(output_dir)

    if generate_models(output_dir):
        print("\n✓ Models generated!")
    else:
        print("\nError: Model generation failed", file=sys.stderr)
        sys.exit(1)


def main():
    parser = argparse.ArgumentParser(
        description="Soleprint Build Tool",
        formatter_class=argparse.RawDescriptionHelpFormatter,
        epilog=__doc__,
    )

    subparsers = parser.add_subparsers(dest="command", required=True)

    # dev command
    dev_parser = subparsers.add_parser("dev", help="Build for development (symlinks)")
    dev_parser.add_argument(
        "--output",
        "-o",
        type=Path,
        default=SPR_ROOT / "gen",
        help="Output directory (default: gen/)",
    )

    # deploy command
    deploy_parser = subparsers.add_parser(
        "deploy", help="Build for deployment (copies)"
    )
    deploy_parser.add_argument(
        "--output",
        "-o",
        type=Path,
        required=True,
        help="Output directory for deployment package",
    )

    # models command
    subparsers.add_parser("models", help="Only regenerate models")

    args = parser.parse_args()

    if args.command == "dev":
        build_dev(args.output.resolve())
    elif args.command == "deploy":
        build_deploy(args.output.resolve())
    elif args.command == "models":
        build_models()


if __name__ == "__main__":
    main()