// Copyright (C) 2019 Storj Labs, Inc.
// See LICENSE for copying information.

package audit_test

import (
	"math/rand"
	"testing"
	"time"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"

	"storj.io/common/memory"
	"storj.io/common/storj"
	"storj.io/common/testcontext"
	"storj.io/common/testrand"
	"storj.io/storj/private/testplanet"
	"storj.io/storj/satellite/audit"
)

// TestAuditPathCollector does the following:
// - start testplanet with 5 nodes and a reservoir size of 3
// - upload 5 files
// - iterate over all the segments in satellite.Metainfo and store them in allPieces map
// - create a audit observer and call metaloop.Join(auditObs)
//
// Then for every node in testplanet:
//    - expect that there is a reservoir for that node on the audit observer
//    - that the reservoir size is <= 2 (the maxReservoirSize)
//    - that every item in the reservoir is unique
func TestAuditPathCollector(t *testing.T) {
	testplanet.Run(t, testplanet.Config{
		SatelliteCount: 1, StorageNodeCount: 5, UplinkCount: 1,
		Reconfigure: testplanet.Reconfigure{
			Satellite: testplanet.ReconfigureRS(3, 4, 5, 5),
		},
	}, func(t *testing.T, ctx *testcontext.Context, planet *testplanet.Planet) {
		satellite := planet.Satellites[0]
		satellite.Audit.Worker.Loop.Pause()

		ul := planet.Uplinks[0]

		// upload 5 remote files with 1 segment
		for i := 0; i < 5; i++ {
			testData := testrand.Bytes(8 * memory.KiB)
			path := "/some/remote/path/" + string(i)
			err := ul.Upload(ctx, satellite, "testbucket", path, testData)
			require.NoError(t, err)
		}

		r := rand.New(rand.NewSource(time.Now().Unix()))
		observer := audit.NewPathCollector(4, r)
		err := satellite.Metainfo.Loop.Join(ctx, observer)
		require.NoError(t, err)

		for _, node := range planet.StorageNodes {
			// expect a reservoir for every node
			require.NotNil(t, observer.Reservoirs[node.ID()])
			require.True(t, len(observer.Reservoirs[node.ID()].Paths) > 1)

			// Require that len paths are <= 3 even though the PathCollector was instantiated with 4
			// because the maxReservoirSize is currently 3.
			require.True(t, len(observer.Reservoirs[node.ID()].Paths) <= 3)

			repeats := make(map[storj.Path]bool)
			for _, path := range observer.Reservoirs[node.ID()].Paths {
				assert.False(t, repeats[path], "expected every item in reservoir to be unique")
				repeats[path] = true
			}
		}
	})
}