/*
 * Mini Object Storage, (C) 2015 Minio, Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package storage

import (
	"bytes"
	"math/rand"
	"strconv"

	. "gopkg.in/check.v1"
)

// API test suite
func APITestSuite(c *C, create func() Storage) {
	testCreateBucket(c, create)
	testMultipleObjectCreation(c, create)
	testPaging(c, create)
	testObjectOverwriteFails(c, create)
	testNonExistantBucketOperations(c, create)
	testBucketRecreateFails(c, create)
	testPutObjectInSubdir(c, create)
	testListBuckets(c, create)
	testListBucketsOrder(c, create)
	testListObjectsTestsForNonExistantBucket(c, create)
	testNonExistantObjectInBucket(c, create)
	testGetDirectoryReturnsObjectNotFound(c, create)
	testDefaultContentType(c, create)
}

func testCreateBucket(c *C, create func() Storage) {
	// TODO
}

func testMultipleObjectCreation(c *C, create func() Storage) {
	objects := make(map[string][]byte)
	storage := create()
	err := storage.StoreBucket("bucket")
	c.Assert(err, IsNil)
	for i := 0; i < 10; i++ {
		randomPerm := rand.Perm(10)
		randomString := ""
		for _, num := range randomPerm {
			randomString = randomString + strconv.Itoa(num)
		}
		key := "obj" + strconv.Itoa(i)
		objects[key] = []byte(randomString)
		err := storage.StoreObject("bucket", key, "", bytes.NewBufferString(randomString))
		c.Assert(err, IsNil)
	}

	// ensure no duplicate etags
	etags := make(map[string]string)
	for key, value := range objects {
		var byteBuffer bytes.Buffer
		storage.CopyObjectToWriter(&byteBuffer, "bucket", key)
		c.Assert(bytes.Equal(value, byteBuffer.Bytes()), Equals, true)

		metadata, err := storage.GetObjectMetadata("bucket", key)
		c.Assert(err, IsNil)
		c.Assert(metadata.Size, Equals, int64(len(value)))

		_, ok := etags[metadata.ETag]
		c.Assert(ok, Equals, false)
		etags[metadata.ETag] = metadata.ETag
	}
}

func testPaging(c *C, create func() Storage) {
	storage := create()
	storage.StoreBucket("bucket")
	resources := BucketResourcesMetadata{}
	objects, resources, err := storage.ListObjects("bucket", resources)
	c.Assert(len(objects), Equals, 0)
	c.Assert(resources.IsTruncated, Equals, false)
	c.Assert(err, IsNil)
	// check before paging occurs
	for i := 0; i < 5; i++ {
		key := "obj" + strconv.Itoa(i)
		storage.StoreObject("bucket", key, "", bytes.NewBufferString(key))
		resources.Maxkeys = 5
		objects, resources, err = storage.ListObjects("bucket", resources)
		c.Assert(len(objects), Equals, i+1)
		c.Assert(resources.IsTruncated, Equals, false)
		c.Assert(err, IsNil)
	}
	// check after paging occurs pages work
	for i := 6; i <= 10; i++ {
		key := "obj" + strconv.Itoa(i)
		storage.StoreObject("bucket", key, "", bytes.NewBufferString(key))
		resources.Maxkeys = 5
		objects, resources, err = storage.ListObjects("bucket", resources)
		c.Assert(len(objects), Equals, 5)
		c.Assert(resources.IsTruncated, Equals, true)
		c.Assert(err, IsNil)
	}
	// check paging with prefix at end returns less objects
	{
		storage.StoreObject("bucket", "newPrefix", "", bytes.NewBufferString("prefix1"))
		storage.StoreObject("bucket", "newPrefix2", "", bytes.NewBufferString("prefix2"))
		resources.Prefix = "new"
		resources.Maxkeys = 5
		objects, resources, err = storage.ListObjects("bucket", resources)
		c.Assert(len(objects), Equals, 2)
	}

	// check ordering of pages
	{
		resources.Prefix = ""
		resources.Maxkeys = 1000
		objects, resources, err = storage.ListObjects("bucket", resources)
		c.Assert(objects[0].Key, Equals, "newPrefix")
		c.Assert(objects[1].Key, Equals, "newPrefix2")
		c.Assert(objects[2].Key, Equals, "obj0")
		c.Assert(objects[3].Key, Equals, "obj1")
		c.Assert(objects[4].Key, Equals, "obj10")
	}
	// check ordering of results with prefix
	{
		resources.Prefix = "obj"
		resources.Maxkeys = 1000
		objects, resources, err = storage.ListObjects("bucket", resources)
		c.Assert(objects[0].Key, Equals, "obj0")
		c.Assert(objects[1].Key, Equals, "obj1")
		c.Assert(objects[2].Key, Equals, "obj10")
		c.Assert(objects[3].Key, Equals, "obj2")
		c.Assert(objects[4].Key, Equals, "obj3")
	}
	// check ordering of results with prefix and no paging
	{
		resources.Prefix = "new"
		resources.Maxkeys = 5
		objects, resources, err = storage.ListObjects("bucket", resources)
		c.Assert(objects[0].Key, Equals, "newPrefix")
		c.Assert(objects[1].Key, Equals, "newPrefix2")
	}
}

func testObjectOverwriteFails(c *C, create func() Storage) {
	storage := create()
	storage.StoreBucket("bucket")
	err := storage.StoreObject("bucket", "object", "", bytes.NewBufferString("one"))
	c.Assert(err, IsNil)
	err = storage.StoreObject("bucket", "object", "", bytes.NewBufferString("three"))
	c.Assert(err, Not(IsNil))
	var bytesBuffer bytes.Buffer
	length, err := storage.CopyObjectToWriter(&bytesBuffer, "bucket", "object")
	c.Assert(length, Equals, int64(len("one")))
	c.Assert(err, IsNil)
	c.Assert(string(bytesBuffer.Bytes()), Equals, "one")
}

func testNonExistantBucketOperations(c *C, create func() Storage) {
	storage := create()
	err := storage.StoreObject("bucket", "object", "", bytes.NewBufferString("one"))
	c.Assert(err, Not(IsNil))
}

func testBucketRecreateFails(c *C, create func() Storage) {
	storage := create()
	err := storage.StoreBucket("string")
	c.Assert(err, IsNil)
	err = storage.StoreBucket("string")
	c.Assert(err, Not(IsNil))
}

func testPutObjectInSubdir(c *C, create func() Storage) {
	storage := create()
	err := storage.StoreBucket("bucket")
	c.Assert(err, IsNil)
	err = storage.StoreObject("bucket", "dir1/dir2/object", "", bytes.NewBufferString("hello world"))
	c.Assert(err, IsNil)
	var bytesBuffer bytes.Buffer
	length, err := storage.CopyObjectToWriter(&bytesBuffer, "bucket", "dir1/dir2/object")
	c.Assert(len(bytesBuffer.Bytes()), Equals, len("hello world"))
	c.Assert(int64(len(bytesBuffer.Bytes())), Equals, length)
	c.Assert(err, IsNil)
}

func testListBuckets(c *C, create func() Storage) {
	storage := create()

	// test empty list
	buckets, err := storage.ListBuckets()
	c.Assert(len(buckets), Equals, 0)
	c.Assert(err, IsNil)

	// add one and test exists
	err = storage.StoreBucket("bucket1")
	c.Assert(err, IsNil)

	buckets, err = storage.ListBuckets()
	c.Assert(len(buckets), Equals, 1)
	c.Assert(err, IsNil)

	// add two and test exists
	err = storage.StoreBucket("bucket2")
	c.Assert(err, IsNil)

	buckets, err = storage.ListBuckets()
	c.Assert(len(buckets), Equals, 2)
	c.Assert(err, IsNil)

	// add three and test exists + prefix
	err = storage.StoreBucket("bucket22")

	buckets, err = storage.ListBuckets()
	c.Assert(len(buckets), Equals, 3)
	c.Assert(err, IsNil)
}

func testListBucketsOrder(c *C, create func() Storage) {
	// if implementation contains a map, order of map keys will vary.
	// this ensures they return in the same order each time
	for i := 0; i < 10; i++ {
		storage := create()
		// add one and test exists
		storage.StoreBucket("bucket1")
		storage.StoreBucket("bucket2")

		buckets, err := storage.ListBuckets()
		c.Assert(len(buckets), Equals, 2)
		c.Assert(err, IsNil)
		c.Assert(buckets[0].Name, Equals, "bucket1")
		c.Assert(buckets[1].Name, Equals, "bucket2")
	}
}

func testListObjectsTestsForNonExistantBucket(c *C, create func() Storage) {
	storage := create()
	resources := BucketResourcesMetadata{Prefix: "", Maxkeys: 1000}
	objects, resources, err := storage.ListObjects("bucket", resources)
	c.Assert(err, Not(IsNil))
	c.Assert(resources.IsTruncated, Equals, false)
	c.Assert(len(objects), Equals, 0)
}

func testNonExistantObjectInBucket(c *C, create func() Storage) {
	storage := create()
	err := storage.StoreBucket("bucket")
	c.Assert(err, IsNil)

	var byteBuffer bytes.Buffer
	length, err := storage.CopyObjectToWriter(&byteBuffer, "bucket", "dir1")
	c.Assert(length, Equals, int64(0))
	c.Assert(err, Not(IsNil))
	c.Assert(len(byteBuffer.Bytes()), Equals, 0)
	switch err := err.(type) {
	case ObjectNotFound:
		{
			c.Assert(err, ErrorMatches, "Object not Found: bucket#dir1")
		}
	default:
		{
			c.Assert(err, Equals, "fails")
		}
	}
}

func testGetDirectoryReturnsObjectNotFound(c *C, create func() Storage) {
	storage := create()
	err := storage.StoreBucket("bucket")
	c.Assert(err, IsNil)

	err = storage.StoreObject("bucket", "dir1/dir2/object", "", bytes.NewBufferString("hello world"))
	c.Assert(err, IsNil)

	var byteBuffer bytes.Buffer
	length, err := storage.CopyObjectToWriter(&byteBuffer, "bucket", "dir1")
	c.Assert(length, Equals, int64(0))
	switch err := err.(type) {
	case ObjectNotFound:
		{
			c.Assert(err.Bucket, Equals, "bucket")
			c.Assert(err.Object, Equals, "dir1")
		}
	default:
		{
			// force a failure with a line number
			c.Assert(err, Equals, "ObjectNotFound")
		}
	}
	c.Assert(len(byteBuffer.Bytes()), Equals, 0)

	var byteBuffer2 bytes.Buffer
	length, err = storage.CopyObjectToWriter(&byteBuffer, "bucket", "dir1/")
	c.Assert(length, Equals, int64(0))
	switch err := err.(type) {
	case ObjectNotFound:
		{
			c.Assert(err.Bucket, Equals, "bucket")
			c.Assert(err.Object, Equals, "dir1/")
		}
	default:
		{
			// force a failure with a line number
			c.Assert(err, Equals, "ObjectNotFound")
		}
	}
	c.Assert(len(byteBuffer2.Bytes()), Equals, 0)
}

func testDefaultContentType(c *C, create func() Storage) {
	storage := create()
	err := storage.StoreBucket("bucket")
	c.Assert(err, IsNil)

	// test empty
	err = storage.StoreObject("bucket", "one", "", bytes.NewBufferString("one"))
	metadata, err := storage.GetObjectMetadata("bucket", "one")
	c.Assert(err, IsNil)
	c.Assert(metadata.ContentType, Equals, "application/octet-stream")

	// test custom
	storage.StoreObject("bucket", "two", "application/text", bytes.NewBufferString("two"))
	metadata, err = storage.GetObjectMetadata("bucket", "two")
	c.Assert(err, IsNil)
	c.Assert(metadata.ContentType, Equals, "application/text")

	// test trim space
	storage.StoreObject("bucket", "three", "\tapplication/json    ", bytes.NewBufferString("three"))
	metadata, err = storage.GetObjectMetadata("bucket", "three")
	c.Assert(err, IsNil)
	c.Assert(metadata.ContentType, Equals, "application/json")
}