#!/usr/bin/env python3
"""
Build script to compile StormLib and prepare it for packaging
"""

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


def get_platform_info():
    """Get platform-specific information"""
    system = platform.system()
    machine = platform.machine()
    
    if system == 'Linux':
        lib_name = 'libstorm.so'
        lib_pattern = '*.so*'
    elif system == 'Darwin':
        lib_name = 'libstorm.dylib'
        lib_pattern = '*.dylib'
    elif system == 'Windows':
        lib_name = 'StormLib.dll'
        lib_pattern = '*.dll'
    else:
        raise RuntimeError(f"Unsupported platform: {system}")
    
    return {
        'system': system,
        'machine': machine,
        'lib_name': lib_name,
        'lib_pattern': lib_pattern
    }


def check_command(cmd):
    """Check if a command is available"""
    try:
        subprocess.run([cmd, '--version'], 
                      stdout=subprocess.DEVNULL, 
                      stderr=subprocess.DEVNULL,
                      check=False)
        return True
    except FileNotFoundError:
        return False


def clone_stormlib(build_dir):
    """Clone StormLib repository"""
    stormlib_dir = build_dir / 'StormLib'
    
    if stormlib_dir.exists():
        print("StormLib directory already exists, using existing clone")
        return stormlib_dir
    
    print("Cloning StormLib repository...")
    result = subprocess.run(
        ['git', 'clone', 'https://github.com/ladislav-zezula/StormLib.git', str(stormlib_dir)],
        cwd=build_dir
    )
    
    if result.returncode != 0:
        raise RuntimeError("Failed to clone StormLib")
    
    return stormlib_dir


def build_stormlib(stormlib_dir, platform_info):
    """Build StormLib using CMake"""
    build_subdir = stormlib_dir / 'build'
    build_subdir.mkdir(exist_ok=True)
    
    print(f"Building StormLib for {platform_info['system']}...")
    
    # Configure with CMake
    cmake_args = [
        'cmake',
        '..',
        '-DCMAKE_BUILD_TYPE=Release',
        '-DBUILD_SHARED_LIBS=ON',
    ]
    
    # Add platform-specific flags
    if platform_info['system'] == 'Darwin':
        # macOS specific flags
        cmake_args.extend([
            '-DCMAKE_OSX_DEPLOYMENT_TARGET=10.13',
        ])
    
    print("Configuring with CMake...")
    result = subprocess.run(cmake_args, cwd=build_subdir)
    if result.returncode != 0:
        raise RuntimeError("CMake configuration failed")
    
    # Build
    print("Compiling...")
    result = subprocess.run(['cmake', '--build', '.', '--config', 'Release'], cwd=build_subdir)
    if result.returncode != 0:
        raise RuntimeError("Compilation failed")
    
    return build_subdir


def find_library(build_dir, platform_info):
    """Find the compiled library file"""
    # Search in common locations
    search_paths = [
        build_dir,
        build_dir / 'Release',
        build_dir / 'Debug',
    ]
    
    for search_path in search_paths:
        if not search_path.exists():
            continue
        
        # Look for library files
        for lib_file in search_path.glob(platform_info['lib_pattern']):
            if platform_info['lib_name'] in lib_file.name:
                return lib_file
    
    raise RuntimeError(f"Could not find compiled library: {platform_info['lib_name']}")


def copy_library_to_package(lib_file, package_dir):
    """Copy the compiled library to the package directory"""
    dest = package_dir / lib_file.name
    
    print(f"Copying {lib_file.name} to package directory...")
    shutil.copy2(lib_file, dest)
    
    # On Linux, also handle symlinks
    if platform.system() == 'Linux':
        # Create a simple versioned name link
        base_name = 'libstorm.so'
        if lib_file.name != base_name:
            symlink_dest = package_dir / base_name
            if symlink_dest.exists() or symlink_dest.is_symlink():
                symlink_dest.unlink()
            os.symlink(lib_file.name, symlink_dest)
            print(f"Created symlink: {base_name} -> {lib_file.name}")
    
    return dest


def main():
    """Main build function"""
    print("="*70)
    print("Building StormLib for PyStorm")
    print("="*70)
    print()
    
    # Get project root directory
    project_root = Path(__file__).parent.absolute()
    build_dir = project_root / 'build'
    package_dir = project_root / 'pystorm'
    
    # Check prerequisites
    print("Checking prerequisites...")
    if not check_command('git'):
        print("ERROR: git is not installed")
        return 1
    
    if not check_command('cmake'):
        print("ERROR: cmake is not installed")
        print("Please install cmake:")
        print("  - Linux: sudo apt-get install cmake")
        print("  - macOS: brew install cmake")
        print("  - Windows: Download from https://cmake.org/")
        return 1
    
    # Get platform info
    platform_info = get_platform_info()
    print(f"Platform: {platform_info['system']} ({platform_info['machine']})")
    print(f"Target library: {platform_info['lib_name']}")
    print()
    
    # Create build directory
    build_dir.mkdir(exist_ok=True)
    
    try:
        # Clone StormLib
        stormlib_dir = clone_stormlib(build_dir)
        
        # Build StormLib
        build_subdir = build_stormlib(stormlib_dir, platform_info)
        
        # Find the compiled library
        lib_file = find_library(build_subdir, platform_info)
        print(f"Found compiled library: {lib_file}")
        
        # Copy to package directory
        dest_file = copy_library_to_package(lib_file, package_dir)
        
        print()
        print("="*70)
        print("Build completed successfully!")
        print("="*70)
        print(f"Library installed to: {dest_file}")
        print()
        print("You can now install the package:")
        print("  pip install -e .")
        print()
        
        return 0
        
    except Exception as e:
        print()
        print("="*70)
        print("Build failed!")
        print("="*70)
        print(f"Error: {e}")
        print()
        return 1


if __name__ == '__main__':
    sys.exit(main())