package engine

import (
	"bytes"
	"reflect"
	"strings"
	"testing"
)

func TestInheritanceSensitivityFollowsCopiesWithoutMaskingNeighbors(t *testing.T) {
	const canary = "INHERITED-CANARY-CREDENTIAL"
	input := parseCompositionDocument(t, "source-1", "parent: {token: "+canary+", plain: visible}\nchild: {extends: parent}\nnext: {extends: child}\nother: {extends: parent}\n")
	for _, classified := range []Path{Keys("parent", "token"), Keys("next", "token")} {
		t.Run(classified.String(), func(t *testing.T) {
			inspection, _ := inheritanceInspectionForTest(t, input)
			inspection.secrets = classifySecretPaths(nil, func(path Path) bool {
				return path.String() == classified.String()
			}, inspection.metadata, inspection.final, inspection.applications, inspection.input)
			for _, path := range []Path{Keys("parent", "token"), Keys("child", "token"), Keys("next", "token"), Keys("other", "token")} {
				explanation, found := inspection.Explain(path)
				if !found || !explanation.Effective.Redacted || strings.Contains(explanation.Effective.YAML, canary) {
					t.Fatalf("sensitive copy %s = %#v, %v", path, explanation, found)
				}
				for _, change := range explanation.History {
					if strings.Contains(change.Before.YAML, canary) || strings.Contains(change.After.YAML, canary) {
						t.Fatalf("historical canary at %s: %#v", path, change)
					}
				}
			}
			plain, found := inspection.Explain(Keys("other", "plain"))
			if !found || plain.Effective.Redacted || plain.Effective.YAML != "visible\n" {
				t.Fatalf("unrelated field = %#v, %v", plain, found)
			}
			var output bytes.Buffer
			if err := inspection.WriteEffective(&output); err != nil || strings.Contains(output.String(), canary) || !strings.Contains(output.String(), "visible") {
				t.Fatalf("effective rendering = %q, %v", output.String(), err)
			}
		})
	}
}

func TestInheritanceSensitivityPreservesDisplacedHistoryAndControl(t *testing.T) {
	const canary = "DISPLACED-CANARY-CREDENTIAL"
	inspection, _ := inheritanceInspectionForTest(t, parseCompositionDocument(t, "source-1", "parent: {branch: {token: "+canary+"}}\nchild: {extends: parent, branch: public}\n"))
	inspection.secrets = classifySecretPaths(nil, func(path Path) bool {
		return path.String() == Keys("parent", "branch", "token").String() || path.String() == Keys("child", inheritanceKey).String()
	}, inspection.metadata, inspection.final, inspection.applications, inspection.input)
	path := Keys("child", "branch", "token")
	explanation, found := inspection.Explain(path)
	if !found || explanation.Effective.Present {
		t.Fatalf("displaced sensitive path = %#v, %v", explanation, found)
	}
	for _, change := range explanation.History {
		if strings.Contains(change.Before.YAML, canary) || strings.Contains(change.After.YAML, canary) ||
			(change.After.Present && !change.After.Redacted) {
			t.Fatalf("displaced secret leaked: %#v", explanation.History)
		}
	}
	var rendered bytes.Buffer
	if err := inspection.WriteExplanation(&rendered, path); err != nil || strings.Contains(rendered.String(), canary) {
		t.Fatalf("displaced explanation rendering = %q, %v", rendered.String(), err)
	}
	control, found := inspection.Explain(Keys("child", inheritanceKey))
	if !found || control.Effective.Present || len(control.History) == 0 || !control.History[0].After.Redacted {
		t.Fatalf("sensitive control history = %#v, %v", control, found)
	}
	info, found := inspection.Metadata().Lookup(Keys("child", "branch"))
	if !found || len(info.Origin.Inheritance) != 0 {
		t.Fatalf("independent replacement provenance = %#v, %v", info, found)
	}
}

func TestInheritanceSensitivityIncludesSchemaTaggedSource(t *testing.T) {
	type entry struct {
		Token string `yaml:"token"`
	}
	type configuration struct {
		Parent struct {
			Token string `yaml:"token" configkit:"secret"`
		} `yaml:"parent"`
		Child entry `yaml:"child"`
	}
	schema, issue := buildSchema(reflect.TypeFor[configuration](), testSecretBinding())
	if issue != nil {
		t.Fatal(issue)
	}
	inspection, _ := inheritanceInspectionForTest(t, parseCompositionDocument(t, "source-1", "parent: {token: TAGGED-CANARY}\nchild: {extends: parent}\n"))
	inspection.secrets = classifySecretPaths(schema, nil, inspection.metadata, inspection.final, inspection.applications, inspection.input)
	child, found := inspection.Explain(Keys("child", "token"))
	if !found || !child.Effective.Redacted || strings.Contains(child.Effective.YAML, "TAGGED-CANARY") {
		t.Fatalf("tagged source copy = %#v, %v", child, found)
	}
}

func TestInheritedSecretReferencesResolveOnlyAfterExpansion(t *testing.T) {
	type entry struct {
		Credential Secret `yaml:"credential"`
	}
	type configuration struct {
		Entries map[string]entry `yaml:"entries"`
	}
	schema, issue := buildSchema(reflect.TypeFor[configuration](), testSecretBinding())
	if issue != nil {
		t.Fatal(issue)
	}
	composed, diagnostics := composeDocuments(parseCompositionDocument(t, "source-1", "entries:\n  parent: {credential: INHERITED_SECRET_NAME}\n  child: {extends: parent}\n"))
	if len(diagnostics) != 0 {
		t.Fatal(diagnostics)
	}
	expanded, diagnostics := expandInheritanceWithOrigins(composed.root, composed.origins, defaultProjectionLimits())
	if len(diagnostics) != 0 {
		t.Fatal(diagnostics)
	}
	lookupCount := 0
	decoded, issues := decodeConfiguration(schema, reflect.Zero(reflect.TypeFor[configuration]()), expanded.root)
	if len(issues) != 0 || lookupCount != 0 {
		t.Fatalf("decoding and lookup order = %#v, %d", issues, lookupCount)
	}
	resolved := resolveSecretReferences(decoded.value, schema, expanded.root, func(name string) (string, bool) {
		lookupCount++
		if name != "INHERITED_SECRET_NAME" {
			t.Fatalf("inherited reference name = %q", name)
		}
		return "RESOLVED-CREDENTIAL-CANARY", true
	})
	if len(resolved.diagnostics) != 0 || lookupCount != 1 ||
		decoded.value.Interface().(configuration).Entries["child"].Credential.Value() != "RESOLVED-CREDENTIAL-CANARY" {
		t.Fatalf("inherited reference resolution = %#v, %d", resolved.diagnostics, lookupCount)
	}
	inspection, _ := inheritanceInspectionFromComposition(t, composed)
	inspection.secrets = classifySecretPaths(schema, nil, inspection.metadata, inspection.final, inspection.applications, inspection.input)
	var rendered bytes.Buffer
	if err := inspection.WriteEffective(&rendered); err != nil || strings.Contains(rendered.String(), "RESOLVED-CREDENTIAL-CANARY") {
		t.Fatalf("reference rendering = %q, %v", rendered.String(), err)
	}
}