import errno
import os
import paramiko


class Uploader(object):
    def __init__(self, host, basepath='', username=None, password=None, keyfile=None, *args, **kwargs):
        self.host = host
        self.basepath = basepath
        self.username = username
        self.password = password
        self.keyfile = keyfile
        self.currentpath = self.basepath
        super(Uploader, self).__init__(*args, **kwargs)
        self.setup()

    def cwd(self):
        return self.currentpath

    def cd(self, path=''):
        if path and path[0] == '/':
            newpath = os.path.abspath(os.path.join(self.basepath, path))
        else:
            newpath = os.path.abspath(os.path.join(self.currentpath, path))
        self.sftp.lstat(newpath)
        self.currentpath = os.path.join(newpath)
        return newpath

    def setup(self):
        self.ssh = paramiko.SSHClient()
        self.ssh.set_missing_host_key_policy(paramiko.AutoAddPolicy())
        ssh_kwargs = {}
        if self.username:
            ssh_kwargs['username'] = self.username
        if self.password:
            ssh_kwargs['password'] = self.password
        if self.keyfile:
            ssh_kwargs['key_filename'] = self.keyfile
        self.ssh.connect(self.host, **ssh_kwargs)
        self.sftp = self.ssh.open_sftp()

    def mkdir(self, path, recursive=True):
        try:
            self.sftp.mkdir(os.path.join(self.basepath, path))
        except IOError, inst:
            if getattr(inst,'errno') == errno.ENOENT and recursive:
                pathdirs = path.split(os.path.sep)
                for pp in range(1,len(pathdirs)):
                    currentpath = os.path.join(self.basepath, *pathdirs[:pp+1])
                    try:
                        self.ftp.lstat(currentpath)
                    except IOError, inst:
                        if getattr(inst,'errno') == errno.ENOENT:
                            self.sftp.mkdir(currentpath)
                        else:
                            raise
            else:
                raise
        return path

    def upload(self, sourcefile, path=None, destname=None, overwrite=False):
        """
        sourcefile can be a filepath or a file object
        so long as the file object has a value for name
        """
        try:
            filename = sourcefile.name
        except AttributeError:
            filename = sourcefile
        if not destname:
            _, destname = os.path.split(filename)
        if path == None:
            path = self.currentpath
        else:
            path = os.path.join(self.basepath, path)
        destpath = os.path.join(path, destname)
        filename_prefix, filename_ext = os.path.splitext(destpath)
        counter = 0
        while True:
            try:
                exists = self.sftp.lstat(destpath)
                if overwrite:
                    print "Filename found, but because overwrite is true I will overwrite it."
                    break
                counter += 1
                destpath = "%s_%d%s" % (filename_prefix, counter, filename_ext)
                print "Filename found, will try %s" % destpath
            except:
                break
        print "Uploading %s to %s" % (filename, destpath)
        self.sftp.put(filename, destpath)
        return destpath

    def finish(self):
        self.sftp.close()
        self.ssh.close()