#!/usr/bin/env python3
# -*- mode: python -*-

import os
import subprocess
import sys

def clean():
    import shutil

    dirs = ['./bin', './lib', './build']

    for dir in dirs:
    	if os.path.isdir(dir): shutil.rmtree(dir)

def is_exe(fpath):
    return os.path.isfile(fpath) and os.access(fpath, os.X_OK)

def which(program):
    fpath, fname = os.path.split(program)

    if fpath:
        if is_exe(program):
            return program
    else:
        for path in os.environ["PATH"].split(os.pathsep):
            path = path.strip('"')
            exe_file = os.path.join(path, program)

            if is_exe(exe_file):
                return exe_file

    return None

def default_generator(platform):
    generator = 'Unix Makefiles'

    if sys.platform == 'darwin':
        generator = 'Xcode'
    elif sys.platform == 'win32':
        generator = 'Visual Studio 14 2015 Win64'

    return generator

def find_cmake():
    cmake = None
    
    if which('cmake3'):
        cmake = 'cmake3'
    elif which('cmake'):
        cmake = 'cmake'
        
    if cmake == None:
        raise Exception("cmake not found")

    return cmake

def parse_args(args):
    options = {}
    generator = default_generator(sys.platform)

    if len(args) == 0:
        return options, generator

    while len(args) > 1:
        option = args.pop(0)

        if '=' not in option:
            raise Exception('bad option: {}'.format(option))

        options[option.split('=')[0]] = option.split('=')[1]

    generator = args[0]

    return options, generator

def main():
    os.chdir(os.path.dirname(os.path.abspath(__file__)))

    if len(sys.argv) == 2 and sys.argv[1] == 'clean':
        clean()
        return

    build_dir = './build'

    if not os.path.isdir(build_dir):
        os.mkdir(build_dir)

    cmake = find_cmake()
    options, generator = parse_args(sys.argv[1:])
    command = [cmake]

    if generator != None:
        command.extend(['-G', generator])

    if options != None:
        for option in options:
            command.extend(['-D', '{}={}'.format(option, options[option])])

    cmake_scripts_dir = '../cmake' # relative to build_dir
    command.append(cmake_scripts_dir)

    subprocess.call(command, cwd=build_dir)

if __name__ == '__main__':
   main()