package tests

import (
	"encoding/json"
	"fmt"
	"time"

	"github.com/prometheus/client_golang/prometheus"
	"github.com/stretchr/testify/require"
	"github.com/zrepl/zrepl/config"
	"github.com/zrepl/zrepl/daemon/filters"
	"github.com/zrepl/zrepl/daemon/pruner"
	"github.com/zrepl/zrepl/endpoint"
	"github.com/zrepl/zrepl/platformtest"
	"github.com/zrepl/zrepl/zfs"
)

func PrunerNotReplicated(ctx *platformtest.Context) {

	platformtest.Run(ctx, platformtest.PanicErr, ctx.RootDataset, `
        DESTROYROOT
        CREATEROOT
        +  "foo bar"
        +  "foo bar@1"
        +  "foo bar@2"
        +  "foo bar@3"
        +  "foo bar@4"
        +  "foo bar@5"
    `)

	c, err := config.ParseConfigBytes([]byte(fmt.Sprintf(`
jobs:
- name: prunetest
  type: push
  filesystems: {
      "%s/foo bar<": true
  }
  connect:
    type: tcp
    address: 255.255.255.255:255
  snapshotting:
    type: manual
  pruning:
    keep_sender:
    - type: not_replicated
    - type: last_n
      count: 1
    keep_receiver:
    - type: last_n
      count: 2
    `, ctx.RootDataset)))
	require.NoError(ctx, err)

	pushJob := c.Jobs[0].Ret.(*config.PushJob)

	dummyHistVec := prometheus.NewHistogramVec(prometheus.HistogramOpts{
		Namespace: "foo",
		Subsystem: "foo",
		Name:      "foo",
		Help:      "foo",
	}, []string{"foo"})

	prunerFactory, err := pruner.NewPrunerFactory(pushJob.Pruning, dummyHistVec)
	require.NoError(ctx, err)

	senderJid := endpoint.MustMakeJobID("sender-job")

	fsfilter, err := filters.DatasetMapFilterFromConfig(pushJob.Filesystems)
	require.NoError(ctx, err)

	sender := endpoint.NewSender(endpoint.SenderConfig{
		FSF: fsfilter,
		Encrypt: &zfs.NilBool{
			B: false,
		},
		JobID: senderJid,
	})

	fs := ctx.RootDataset + "/foo bar"

	// create a replication cursor to make pruning work at all
	_, err = endpoint.CreateReplicationCursor(ctx, fs, fsversion(ctx, fs, "@2"), senderJid)
	require.NoError(ctx, err)

	p := prunerFactory.BuildSenderPruner(ctx, sender, sender)

	p.Prune()

	report := p.Report()

	reportJSON, err := json.MarshalIndent(report, "", "  ")
	require.NoError(ctx, err)
	ctx.Logf("%s\n", string(reportJSON))

	require.Equal(ctx, pruner.Done.String(), report.State)
	require.Len(ctx, report.Completed, 1)
	fsReport := report.Completed[0]
	require.Equal(ctx, fs, fsReport.Filesystem)
	require.Empty(ctx, fsReport.SkipReason)
	require.Empty(ctx, fsReport.LastError)
	require.Len(ctx, fsReport.DestroyList, 1)
	require.Equal(ctx, fsReport.DestroyList[0], pruner.SnapshotReport{
		Name:       "1",
		Replicated: true,
		Date:       fsReport.DestroyList[0].Date,
	})

}

func PrunerNoKeepNotReplicatedNoKeepStepHoldConvertsAnyStepHoldToBookmark(ctx *platformtest.Context) {

	platformtest.Run(ctx, platformtest.PanicErr, ctx.RootDataset, `
        DESTROYROOT
        CREATEROOT
        +  "foo bar"
        +  "foo bar@1"
        +  "foo bar@2"
        +  "foo bar@3"
        +  "foo bar@4"
        +  "foo bar@5"
    `)

	c, err := config.ParseConfigBytes([]byte(fmt.Sprintf(`
jobs:
- name: prunetest
  type: push
  filesystems: {
      "%s/foo bar<": true
  }
  connect:
    type: tcp
    address: 255.255.255.255:255
  snapshotting:
    type: manual
  pruning:
    keep_sender:
    - type: last_n
      count: 1
    keep_receiver:
    - type: last_n
      count: 2
    `, ctx.RootDataset)))
	require.NoError(ctx, err)

	pushJob := c.Jobs[0].Ret.(*config.PushJob)

	dummyHistVec := prometheus.NewHistogramVec(prometheus.HistogramOpts{
		Namespace: "foo",
		Subsystem: "foo",
		Name:      "foo",
		Help:      "foo",
	}, []string{"foo"})

	prunerFactory, err := pruner.NewPrunerFactory(pushJob.Pruning, dummyHistVec)
	require.NoError(ctx, err)

	senderJid := endpoint.MustMakeJobID("sender-job")

	fsfilter, err := filters.DatasetMapFilterFromConfig(pushJob.Filesystems)
	require.NoError(ctx, err)

	sender := endpoint.NewSender(endpoint.SenderConfig{
		FSF: fsfilter,
		Encrypt: &zfs.NilBool{
			B: false,
		},
        JobID: senderJid,
	})

	fs := ctx.RootDataset + "/foo bar"

	// create a replication cursor to make pruning work at all
	_, err = endpoint.CreateReplicationCursor(ctx, fs, fsversion(ctx, fs, "@2"), senderJid)
	require.NoError(ctx, err)

	// create step holds for the incremental @2->@3
	endpoint.HoldStep(ctx, fs, fsversion(ctx, fs, "@2"), senderJid)
	endpoint.HoldStep(ctx, fs, fsversion(ctx, fs, "@3"), senderJid)
	// create step holds for another job
	otherJid := endpoint.MustMakeJobID("other-job")
	endpoint.HoldStep(ctx, fs, fsversion(ctx, fs, "@2"), otherJid)
	endpoint.HoldStep(ctx, fs, fsversion(ctx, fs, "@3"), otherJid)

	p := prunerFactory.BuildSenderPruner(ctx, sender, sender)

	p.Prune()

	report := p.Report()

	reportJSON, err := json.MarshalIndent(report, "", "  ")
	require.NoError(ctx, err)
	ctx.Logf("%s\n", string(reportJSON))

	require.Equal(ctx, pruner.Done.String(), report.State)
	require.Len(ctx, report.Completed, 1)
	fsReport := report.Completed[0]
	require.Equal(ctx, fs, fsReport.Filesystem)
	require.Empty(ctx, fsReport.SkipReason)
	require.Empty(ctx, fsReport.LastError)
	expectDestroyList := []pruner.SnapshotReport{
		{
			Name:       "1",
			Replicated: true,
		},
		{
			Name:       "2",
			Replicated: true,
		},
		{
			Name:       "3",
			Replicated: true,
		},
		{
			Name:       "4",
			Replicated: true,
		},
	}
	for _, d := range fsReport.DestroyList {
		d.Date = time.Time{}
	}
	require.Subset(ctx, fsReport.DestroyList, expectDestroyList)
}



func PrunerNoKeepNotReplicatedButKeepStepHold(ctx *platformtest.Context) {

	platformtest.Run(ctx, platformtest.PanicErr, ctx.RootDataset, `
        DESTROYROOT
        CREATEROOT
        +  "foo bar"
        +  "foo bar@1"
        +  "foo bar@2"
        +  "foo bar@3"
        +  "foo bar@4"
        +  "foo bar@5"
    `)

	c, err := config.ParseConfigBytes([]byte(fmt.Sprintf(`
jobs:
- name: prunetest
  type: push
  filesystems: {
      "%s/foo bar<": true
  }
  connect:
    type: tcp
    address: 255.255.255.255:255
  snapshotting:
    type: manual
  pruning:
    keep_sender:
    - type: step_holds
    - type: last_n
      count: 1
    keep_receiver:
    - type: last_n
      count: 2
    `, ctx.RootDataset)))
	require.NoError(ctx, err)

	pushJob := c.Jobs[0].Ret.(*config.PushJob)

	dummyHistVec := prometheus.NewHistogramVec(prometheus.HistogramOpts{
		Namespace: "foo",
		Subsystem: "foo",
		Name:      "foo",
		Help:      "foo",
	}, []string{"foo"})

	prunerFactory, err := pruner.NewPrunerFactory(pushJob.Pruning, dummyHistVec)
	require.NoError(ctx, err)

	senderJid := endpoint.MustMakeJobID("sender-job")

	fsfilter, err := filters.DatasetMapFilterFromConfig(pushJob.Filesystems)
	require.NoError(ctx, err)

	sender := endpoint.NewSender(endpoint.SenderConfig{
		FSF: fsfilter,
		Encrypt: &zfs.NilBool{
			B: false,
		},
        JobID: senderJid,
	})

	fs := ctx.RootDataset + "/foo bar"

	// create a replication cursor to make pruning work at all
	_, err = endpoint.CreateReplicationCursor(ctx, fs, fsversion(ctx, fs, "@2"), senderJid)
	require.NoError(ctx, err)

	// create step holds for the incremental @2->@3
	endpoint.HoldStep(ctx, fs, fsversion(ctx, fs, "@2"), senderJid)
	endpoint.HoldStep(ctx, fs, fsversion(ctx, fs, "@3"), senderJid)
	// create step holds for another job
	otherJid := endpoint.MustMakeJobID("other-job")
	endpoint.HoldStep(ctx, fs, fsversion(ctx, fs, "@2"), otherJid)
	endpoint.HoldStep(ctx, fs, fsversion(ctx, fs, "@3"), otherJid)

	p := prunerFactory.BuildSenderPruner(ctx, sender, sender)

	p.Prune()

	report := p.Report()

	reportJSON, err := json.MarshalIndent(report, "", "  ")
	require.NoError(ctx, err)
	ctx.Logf("%s\n", string(reportJSON))

	require.Equal(ctx, pruner.Done.String(), report.State)
	require.Len(ctx, report.Completed, 1)
	fsReport := report.Completed[0]
	require.Equal(ctx, fs, fsReport.Filesystem)
	require.Empty(ctx, fsReport.SkipReason)
	require.Empty(ctx, fsReport.LastError)
	expectDestroyList := []pruner.SnapshotReport{
		{
			Name:       "1",
			Replicated: true,
		},
		{
			Name:       "4",
			Replicated: true,
		},
	}
	for _, d := range fsReport.DestroyList {
		d.Date = time.Time{}
	}
	require.Subset(ctx, fsReport.DestroyList, expectDestroyList)
}