from datetime import datetime
from datetime import timedelta

import utils
import recipeparse

from django.db import transaction

from layerindex.models import Recipe
from rrs.models import Maintainer, RecipeUpgrade

from recipe_upstream import vercmp_string

"""
    Discovers the upgraded packages in the last day.
"""
def update_recipe_upgrades(layerbranch, repodir, layerdir, config_data, logger):
    today = datetime.today()
    yesterday = today - timedelta(days = 7)
    todaystr = today.strftime("%Y-%m-%d")
    yesterdaystr = yesterday.strftime("%Y-%m-%d")

    temp_branch = "recipe_upgrades"

    logger.debug("Check recent upgrades")

    utils.runcmd("git checkout origin/master ", repodir)

    # try to delete temp_branch if exists
    try:
        utils.runcmd("git branch -D " + temp_branch, repodir)
    except:
        pass


    transaction.enter_transaction_management()
    transaction.managed(True)
    commits = utils.runcmd("git log --since='" + yesterdaystr + "' --until='" +
                            todaystr + "' --format='%H' --reverse", repodir)
    for commit in commits.split("\n"):
        if commit != "":
            logger.debug("Analysing commit %s" % commit)
            commit_files = get_commit_files(commit, repodir, layerdir, logger)

            utils.runcmd("git branch " + temp_branch, repodir)
            utils.runcmd("git checkout " + temp_branch, repodir)
            utils.runcmd("git reset --hard " + commit, repodir)

            for path in commit_files:
                try:
                    envdata = bb.cache.Cache.loadDataFull(str(path), [],
                                config_data)
                    pn = envdata.getVar("PN", True)
                    pv = envdata.getVar("PV", True)
                except Exception as e:
                    logger.warn("Recipe %s couldn't be parsed, %s" %
                                (path, str(e)))
                    continue

                try:
                    recipe = Recipe.objects.get(layerbranch = layerbranch,
                            pn__exact = pn)
                except Exception as e:
                    # Most probably a native found
                    logger.warn("Recipe %s not found in database, %s" %
                                (pn, str(e)))
                    continue

                try:
                    latest_upgrade = RecipeUpgrade.objects.filter(
                            recipe = recipe).order_by('-commit_date')[0]
                    prev_pv = latest_upgrade.version
                except Exception as e:
                    prev_pv = None

                # if no previous version in database consider it an upgrade
                try:
                    if not prev_pv or vercmp_string(prev_pv, pv) == -1:
                        logger.debug("Detected upgrade for %s in commit %s." % (pn, commit))
                        create_upgrade(commit, repodir, recipe, pv, logger)
                except:
                    logger.error("vercmp_string: %s, %s - %s" % (recipe.pn,
                        prev_pv, pv))

            utils.runcmd("git checkout origin/master ", repodir)
            utils.runcmd("git branch -D " + temp_branch, repodir)

    transaction.commit()
    transaction.leave_transaction_management()

"""
    Returns a list containing the fullpaths to the recipes from a commit.
"""
def get_commit_files(commit, repodir, layerdir, logger):
    commit_files = []
    layerdir_start = os.path.normpath(layerdir) + os.sep

    files = utils.runcmd("git log --name-only --format='%n' -n 1 " + commit,
                            repodir, logger=logger)

    for f in files.split("\n"):
        if f != "":
            fullpath = os.path.join(repodir, f)
            # Skip deleted files in commit
            if not os.path.exists(fullpath):
                continue
            (typename, _, filename) = recipeparse.detect_file_type(fullpath,
                                        layerdir_start)
            if typename == 'recipe':
                commit_files.append(fullpath)

    return commit_files

""" 
    Insert new entry in the RecipeUpgrade table.
"""
def create_upgrade(commit, repodir, recipe, pv, logger):
    from email.utils import parsedate_tz, mktime_tz
    info = utils.runcmd("git log  --format='%an;%ae;%ad;%cd' --date=rfc -n 1 " + commit,
                            destdir=repodir, logger=logger)

    maintainer_name = info.split(';')[0]
    maintainer_email = info.split(';')[1]
    author_date = info.split(';')[2]
    commit_date = info.split(';')[3]

    maintainer = Maintainer.create_or_update(maintainer_name, maintainer_email)
   
    title = utils.runcmd("git log --format='%s' -n 1 " + commit,
                            repodir, logger=logger)

    upgrade = RecipeUpgrade()
    upgrade.recipe = recipe
    upgrade.maintainer = maintainer
    upgrade.author_date = datetime.utcfromtimestamp(mktime_tz(
                                    parsedate_tz(author_date)))
    upgrade.commit_date = datetime.utcfromtimestamp(mktime_tz(
                                    parsedate_tz(commit_date)))
    upgrade.version = pv
    upgrade.sha1 = commit
    upgrade.title = title.strip()
    upgrade.save()