#!/usr/bin/env python

import os
import sys
import yaml

from lib import Formula
from lib import FormulaRepo

# constants
CONFIG_FILE = 'sfm.yaml'
REPO_STATE = 'latest'

# reads configuration and returns the dictionary
def read_config():
    f = open(CONFIG_FILE, 'r')
    conf = yaml.load(f)
    f.close()

    return conf

# creates the formulas directory if it doesn't exist
def check_formula_dir(formulas_dir):
    # check if the formulas directory is actually a directory
    if not os.path.isdir(formulas_dir):
        # check if it's a file
        if os.path.exists(formulas_dir):
            print(str(formulas_dir) + ' exists but is not a directory. Please fix this.')
            sys.exit(1)
        # create it if not
        else:
            os.makedirs(formulas_dir)

# loops through the array of repos and downloads them
def get_formulas(formulas, formulas_dir, formulas_url):
    # loop through the defined formulas
    for formula_def in formulas:
        # create a formula object
        formula = Formula.Formula(formula_def, formulas_dir, formulas_url)
        # create a repo object for the formula
        formula_repo = FormulaRepo.FormulaRepo(formula)

        # retrieve our formula
        formula_repo.retrieve()

        # get the repo tracking information from the formula definition
        tracking_branch = formula.get_tracking_state()
        # make sure our formula's repo is up-to-date with the latest tracked version
        formula_repo.check_tracking_info(tracking_branch)

        # pull any new commits for the repo
        formula_repo.pull_updates()

# purge un-managed formulas
def clean_formulas(conf):
    if conf['purge_formulas']:
        print('Cleaning out unmanaged formulas')
        
    else:
        print('Not cleaning out unmanaged formulas')

# main program
def main():
    # read configuration settings
    conf = read_config()

    # make sure the formulas directory exists
    check_formula_dir(conf['formulas_dir'])

    # do the formula stuff
    get_formulas(conf['formulas'], conf['formulas_dir'], conf['formulas_url'])

    # clean unmanaged formulas
    #clean_formulas(conf)

# run main
main()