import os

from django.db import models
from django.contrib.auth.models import User
from django.utils.translation import ugettext_lazy as _
from pygments import lexers, highlight, formatters, util
from mptt.models import MPTTModel, TreeForeignKey
from sizefield.models import FileSizeField

from apps.free_license.models import FreeLicense
from apps.snippet.highlight import NakedHtmlFormatter


class Bundle(models.Model):
    class Meta:
        # Every user must pick unique names for their bundles
        unique_together = ('uploader','name')
        ordering = ['-pub_date']

    name = models.SlugField(help_text=_("Your bundle will be accessible " +
        "from a URL that uses the name you enter here, so choose wisely. " +
        "Acceptable characters: alphanumeric characters, hyphens, and " +
        "underscores."))
    uploader = models.ForeignKey(User)
    description = models.TextField(blank=True, null=True, help_text=_(
        "Optional. If this field is left empty and the checkbox below "
        "is ticked, then the DESCRIPTION file (if it exists) will be "
        "used as the bundle description instead."))
    octave_format = models.BooleanField(_("Is the bundle formatted according"
        " to Octave package manager standards?"), default=False)
    # If octave_format is true and there is a DESCRIPTION file in the root
    description_file = models.ForeignKey('BundleFile', blank=True, null=True,
        related_name="described")
    free_license = models.ForeignKey(FreeLicense, default=1)
    pub_date = models.DateTimeField('date uploaded', auto_now_add=True)
    mod_date = models.DateTimeField('date last modified', auto_now=True)
    done_uploading = models.BooleanField(default=False)
    file_name = models.CharField(max_length=256) # the uploaded file
    latest_version = models.IntegerField(default=1)

    def __unicode__(self):
        return self.name

    @models.permalink
    def get_absolute_url(self):
        return ('bundle_details', [self.uploader.username, self.name])

    def get_temp_path(self):
        """
        Returns the path to where the file is initially uploaded
        """
        return os.path.join('tmp', 'bundles',
            "%d_%d" % (self.id, self.latest_version))


class BundleVersion(models.Model):
    class Meta:
        unique_together = ('bundle', 'version')
    """
    Needed to allow users to download the originally-uploaded files
    """
    bundle = models.ForeignKey(Bundle)
    version = models.IntegerField()
    file_name = models.CharField(max_length=256)

    def __unicode__(self):
        return self.file_name


class BundleFile(MPTTModel):
    bundle = models.ForeignKey(Bundle)
    version = models.IntegerField()
    parent = TreeForeignKey('self', null=True, blank=True,
        related_name='children')
    name = models.CharField(max_length=256)
    is_dir = models.BooleanField()
    code = models.TextField(null=True, blank=True)
    full_path = models.CharField(max_length=256)
    file_size = FileSizeField(default=0) # for directories

    def __unicode__(self):
        return self.name

    def get_path(self):
        if self.parent:
            return os.path.join(self.parent.get_path(), self.name)
        else:
            return self.name

    def get_lines(self):
        return self.code.splitlines()

    def save_file_contents(self, file, original_filename=None):
        code = file.read()

        if original_filename is not None:
            filename = original_filename
        else:
            filename = file.name

        try:
            lexer = lexers.get_lexer_for_filename(filename)
            print "lexer is:"
            print lexer
        except util.ClassNotFound:
            print "can't guess the lexer"
            lexer = lexers.TextLexer()

        self.code = highlight(code, lexer, NakedHtmlFormatter())
        self.save()

    @models.permalink
    def get_absolute_url(self):
        return ('bundlefile_details', [
            self.bundle.uploader.username,
            self.bundle.name,
            self.version,
            self.get_path()
        ])