from lib.Utils import Utils
import os
import sh
import sys

class FormulaRepo():

    # class variables
    repo_url = ''
    repo_path = ''
    repo = None

    # class constructor
    def __init__(self, formula):
        self.repo_url = formula.git_url
        self.repo_path = formula.local_path

    # sets up our class' repo instance
    def bake(self):
        self.repo = sh.git.bake(_cwd=self.repo_path)

    # list of git branches
    def get_branches(self):
        # define our branch array
        branches = []
        # fetch output of git branches
        branch_lines = self.repo.branch()
        # loop through the branches
        for line in branch_lines:
            bits = Utils.remove_ansi_from_list(line.split())
            # check if the branch was marked as current
            if bits[0] == '*':
                branches.append(bits[1])
            else:
                branches.append(bits[0])

        # return our list of branch names
        return branches

    # get current branch
    def get_current_branch(self):
        branches = self.repo.branch()
        # loop through the branches
        for line in branches:
            bits = Utils.remove_ansi_from_list(line.split())
            # check for if a branch is listed as current
            if bits[0] == '*':
                # return the branch name
                return bits[1]

        # return false if no branch is selected
        return False

    # switch to branch
    def switch_branch(self, branch):
        print('Switching %s to the \'%s\' branch' % (self.repo_path, branch))
        self.repo.checkout(branch)

    # retrieves repo from remote location
    def retrieve(self):
        # check if the destination directory exists
        if not os.path.exists(self.repo_path):
            # clone git repo
            print('Downloading ' + self.repo_url + ' into ' + self.repo_path)
            sh.git.clone(self.repo_url, self.repo_path)
        else:
            # let the user know it's already downloaded so we'll update it later
            print(self.repo_path + ' already exists, so we\'re not downloading it again.')

        # set up our class repo instance
        self.bake()

    # check if the repo is up to date
    def check_tracking_info(self, branch):
        if branch != False:
            # tracking a specific branch on the repo
            # check to make sure that the given branch name actually exists first
            if not branch in self.get_branches():
                print('%s is not an existing branch name for %s - please fix this.' % (branch, self.repo_path))
                sys.exit(1)

            repo_branch = self.get_current_branch()
            # check to make sure that the current tracked branch is, in fact, what we want
            if branch != repo_branch:
                self.switch_branch(branch)

            # let the user know which branch we're using
            print('For %s, we\'re using the \'%s\' branch.' % (self.repo_path, branch))
        else:
            # no branch was specified, so we're going with what's there
            print('Using the default/current branch for %s' % (self.repo_path))


    # pull any new updates for the repo
    def pull_updates(self):
        print('Pulling updates for %s.' % self.repo_path)
        # git pull
        self.repo.pull()