import tempfile
import shutil
import mock
import os
import random
import string

from tests.util import random_lbry_hash
from lbrynet.core.BlobManager import DiskBlobManager
from lbrynet.core.HashAnnouncer import DummyHashAnnouncer
from lbrynet.core.Peer import Peer
from lbrynet import conf
from lbrynet.core.cryptoutils import get_lbry_hash_obj
from twisted.trial import unittest

from twisted.internet import defer

class BlobManagerTest(unittest.TestCase):
    def setUp(self):
        conf.initialize_settings()
        self.blob_dir = tempfile.mkdtemp()
        self.db_dir = tempfile.mkdtemp()
        hash_announcer  = DummyHashAnnouncer()
        self.bm = DiskBlobManager(hash_announcer, self.blob_dir, self.db_dir)
        self.peer = Peer('somehost',22)

    def tearDown(self):
        self.bm.stop()
        # BlobFile will try to delete itself  in _close_writer
        # thus when calling rmtree we may get a FileNotFoundError
        # for the blob file
        shutil.rmtree(self.blob_dir, ignore_errors=True)
        shutil.rmtree(self.db_dir)

    @defer.inlineCallbacks
    def _create_and_add_blob(self):
        # create and add blob to blob manager
        data_len = random.randint(1,1000)
        data = ''.join(random.choice(string.lowercase) for data_len in range(data_len))

        hashobj = get_lbry_hash_obj()
        hashobj.update(data)
        out=hashobj.hexdigest()
        blob_hash=out

        # create new blob
        yield self.bm.setup()
        blob = yield self.bm.get_blob(blob_hash,len(data))

        writer, finished_d = yield blob.open_for_writing(self.peer)
        yield writer.write(data)
        yield self.bm.blob_completed(blob)
        yield self.bm.add_blob_to_upload_history(blob_hash,'test',len(data))

        # check to see if blob is there
        self.assertTrue(os.path.isfile(os.path.join(self.blob_dir,blob_hash)))
        blobs = yield self.bm.get_all_verified_blobs()
        self.assertTrue(blob_hash in blobs)
        defer.returnValue(blob_hash)

    @defer.inlineCallbacks
    def test_create_blob(self):
        blob_hashes = []

        # create a bunch of blobs
        for i in range(0,10):
            blob_hash = yield self._create_and_add_blob()
            blob_hashes.append(blob_hash)
        blobs = yield self.bm.get_all_verified_blobs()
        self.assertEqual(10,len(blobs))


    @defer.inlineCallbacks
    def test_delete_blob(self):
        # create blob
        blob_hash  = yield self._create_and_add_blob()
        blobs = yield self.bm.get_all_verified_blobs()
        self.assertEqual(len(blobs),1)

        # delete blob 
        yield self.bm.delete_blobs([blob_hash])
        self.assertFalse(os.path.isfile(os.path.join(self.blob_dir,blob_hash)))
        blobs = yield self.bm.get_all_verified_blobs()
        self.assertEqual(len(blobs),0)
        blobs = yield self.bm._get_all_blob_hashes() 
        self.assertEqual(len(blobs),0)

        # delete blob that does not exist, nothing will
        # happen
        blob_hash= random_lbry_hash()
        out = yield self.bm.delete_blobs([blob_hash])


    @defer.inlineCallbacks
    def test_delete_open_blob(self):
        # Test that a blob that is opened for writing will not be deleted

        # create blobs
        blob_hashes =[]
        for i in range(0,10):
            blob_hash  = yield self._create_and_add_blob()
            blob_hashes.append(blob_hash)
        blobs = yield self.bm.get_all_verified_blobs()
        self.assertEqual(len(blobs),10)

        # open the last blob
        blob = yield self.bm.get_blob(blob_hashes[-1])
        writer, finished_d = yield blob.open_for_writing(self.peer)

        # delete the last blob and check if it still exists
        out = yield self.bm.delete_blobs([blob_hash])
        blobs = yield self.bm.get_all_verified_blobs()
        self.assertEqual(len(blobs),10)
        self.assertTrue(blob_hashes[-1] in blobs)
        self.assertTrue(os.path.isfile(os.path.join(self.blob_dir,blob_hashes[-1])))