package engine

import (
	"reflect"
	"testing"

	"gitea.maximumdirect.net/eric/ConfigKit/internal/document"
)

func TestHistoryResolutionRetainsOriginalShapeAttributionBehindReplayGroup(t *testing.T) {
	before := &document.Node{Kind: document.Mapping, Mapping: []document.Entry{{
		Key: "0", Value: &document.Node{Kind: document.String, Text: "old"},
	}}}
	after := &document.Node{Kind: document.Sequence, Sequence: []*document.Node{{
		Kind: document.String, Text: "new", Sensitive: true,
	}}}
	baseline := &document.Node{Kind: document.Mapping, Mapping: []document.Entry{{
		Key: "settings", Value: before,
	}}}
	parentDependency := Keys("parent-dependency")
	childDependency := Keys("child-dependency")
	snapshots := []resolutionSnapshot{
		{
			change: Change{
				Path: Keys("settings"), Origin: Origin{Layer: LayerResolution, Operation: ChangeDerivedDefault},
				Reasons: []string{"parent normalization"}, Dependencies: []Path{parentDependency},
			},
			before: before, after: after,
		},
		{
			change: Change{
				Path: parseOverrideTestPath(t, "/settings/0"), Origin: Origin{Layer: LayerResolution, Operation: ChangeNormalization},
				Reasons: []string{"child normalization"}, Dependencies: []Path{childDependency},
			},
			before: before.Mapping[0].Value,
			after:  after.Sequence[0],
		},
	}

	builder := newHistoryBuilder()
	builder.observeBaseline(baseline)
	builder.setScratch(baseline)
	builder.observeResolutionEvidence(snapshots)
	model := builder.freeze()

	if got := model.resolutionPayload.replayGroups; len(got) != 1 ||
		got[0].coveringRecordID != 0 || !reflect.DeepEqual(got[0].originalRecordIDs, []int{0, 1}) ||
		!reflect.DeepEqual(got[0].change.Reasons, []string{"parent normalization", "child normalization"}) ||
		!reflect.DeepEqual(got[0].change.Dependencies, []Path{parentDependency, childDependency}) ||
		got[0].change.Origin.Operation != ChangeNormalization {
		t.Fatalf("replay group lost original references or merged annotations: %#v", got)
	}
	if len(model.resolutionPayload.snapshots) != 2 ||
		model.resolutionPayload.snapshots[1].change.Reasons[0] != "child normalization" ||
		model.resolutionPayload.snapshots[1].change.Dependencies[0].String() != childDependency.String() ||
		model.resolutionPayload.snapshots[0].before != before || model.resolutionPayload.snapshots[1].after != after.Sequence[0] {
		t.Fatalf("original resolution records or their roots were not retained: %#v", model.resolutionPayload.snapshots)
	}

	keyPath := Keys("settings", "0")
	keySelections := model.selectHistory(keyPath)
	if len(keySelections) != 3 || !keySelections[0].after || keySelections[1].phase != historyPhaseResolution ||
		!keySelections[1].before || keySelections[1].after || !keySelections[2].before || keySelections[2].after {
		t.Fatalf("mapping-key history did not retain its removed side: %#v", keySelections)
	}
	if got := keySelections[1].previous; len(got) != 1 || got[0].Layer != LayerDefault {
		t.Fatalf("removed key previous origin = %#v, want baseline origin", got)
	}

	indexPath := Keys("settings").Index(0)
	indexSelections := model.selectHistory(indexPath)
	if len(indexSelections) != 2 || indexSelections[0].phase != historyPhaseResolution ||
		!indexSelections[0].after || indexSelections[0].before || !indexSelections[1].after || indexSelections[1].before {
		t.Fatalf("sequence-index history did not retain introduced sides: %#v", indexSelections)
	}
	if len(indexSelections[0].previous) != 0 {
		t.Fatalf("introduced index inherited a different key's previous origin: %#v", indexSelections[0].previous)
	}
	if got := indexSelections[1].attribution; got.origin.Operation != ChangeNormalization ||
		!reflect.DeepEqual(got.reasons, []string{"child normalization"}) ||
		!reflect.DeepEqual(got.dependencies, []Path{childDependency}) {
		t.Fatalf("covered original attribution = %#v", got)
	}

	foundSensitive := false
	for _, observation := range model.observations {
		if observation.phase == historyPhaseResolution && sameConcreteHistoryPath(observation.path, indexPath) && observation.sensitive {
			foundSensitive = true
		}
	}
	if !foundSensitive {
		t.Fatal("original resolution subtree sensitivity was omitted from observations")
	}
}

func TestMetadataFinalizationRegistersResolutionInventoryAndRoots(t *testing.T) {
	t.Parallel()

	beforeShape := &document.Node{Kind: document.Mapping, Mapping: []document.Entry{{
		Key: "0", Value: &document.Node{Kind: document.String, Text: "old"},
	}}}
	afterShape := &document.Node{Kind: document.Sequence, Sequence: []*document.Node{{
		Kind: document.String, Text: "new", Sensitive: true,
	}}}
	before := &document.Node{Kind: document.Mapping, Mapping: []document.Entry{{Key: "shape", Value: beforeShape}}}
	final := &document.Node{Kind: document.Mapping, Mapping: []document.Entry{{Key: "shape", Value: afterShape}}}
	changePath := parseOverrideTestPath(t, "/shape/0")
	snapshot := resolutionSnapshot{
		change: Change{
			Path: changePath, Origin: Origin{Layer: LayerResolution, Operation: ChangeNormalization},
			Reasons: []string{"changed dynamic shape"}, Dependencies: []Path{Keys("source")},
		},
		before: beforeShape.Mapping[0].Value,
		after:  afterShape.Sequence[0],
	}
	parentSnapshot := resolutionSnapshot{
		change: Change{
			Path: Keys("shape"), Origin: Origin{Layer: LayerResolution, Operation: ChangeNormalization},
			Reasons: []string{"replaced container"},
		},
		before: beforeShape,
		after:  afterShape,
	}

	var metadata Metadata
	snapshots := []resolutionSnapshot{parentSnapshot, snapshot}
	builder := newHistoryBuilder()
	builder.setScratch(before)
	builder.observeDocument(before, historyPhaseBaseline)
	builder.observeDocument(final, historyPhasePostCLI)
	builder.prefixReady = true
	builder.observeResolutionEvidence(snapshots)
	metadata.historyBuilder = builder
	freezeMetadataHistory(&metadata, final)
	if got := metadata.HistoricalPaths(); len(got) != 3 || got[0].String() != "" || got[1].String() != "/shape" || got[2].String() != "/shape/0" {
		t.Fatalf("historical paths = %#v", got)
	}
	keyPath := Keys("shape", "0")
	indexPath := Keys("shape").Index(0)
	if !metadata.hasHistoricalPath(keyPath) || !metadata.hasHistoricalPath(indexPath) {
		t.Fatalf("resolution shape inventory omitted key or index: %#v", metadata.HistoricalPaths())
	}
	if got := metadata.historyModel.selectHistory(keyPath); len(got) != 2 || !got[0].before || got[0].after || !got[1].before || got[1].after {
		t.Fatalf("removed mapping-key resolution selection = %#v", got)
	}
	if got := metadata.historyModel.selectHistory(indexPath); len(got) != 2 || got[0].before || !got[0].after || got[1].before || !got[1].after {
		t.Fatalf("introduced sequence-index resolution selection = %#v", got)
	}
	var retainedBefore, retainedAfter bool
	for _, root := range metadata.historyModel.documentRoots() {
		retainedBefore = retainedBefore || root == snapshot.before
		retainedAfter = retainedAfter || root == snapshot.after
	}
	if !retainedBefore || !retainedAfter {
		t.Fatalf("resolution roots not enumerated: before=%v after=%v", retainedBefore, retainedAfter)
	}
}