package policy_test

import (
	"context"
	"encoding/json"
	"os"
	"os/exec"
	"path/filepath"
	"strings"
	"testing"
	"time"

	"github.com/netkingdom/access-engine/internal/policy"
	"github.com/netkingdom/access-engine/pkg/api"
)

// FLEX-WP-0040-T07: compact-sitting v14 admits the present-existing requester
// service:nk-bind-executor (INFD-WP-0010, GH-DEC-2026-026 class C2). v13 stays
// in examples/informed-decision-lifecycle-review as the rollback reference.
func TestInformedDecisionPresentExistingV14(t *testing.T) {
	dir := filepath.Join(repoRoot(t), "examples", "informed-decision-present-existing-review")
	pkg, err := policy.LoadAndValidateFile(context.Background(), filepath.Join(dir, "policy.md"))
	if err != nil {
		t.Fatal(err)
	}
	if !pkg.Valid {
		t.Fatalf("invalid package: %+v", pkg.Validation)
	}
	if pkg.Metadata.ID != "informed-decision.compact-sitting" || pkg.Metadata.Version != "v14" {
		t.Fatalf("package %s %s", pkg.Metadata.ID, pkg.Metadata.Version)
	}
	raw, err := os.ReadFile(filepath.Join(dir, "pin.json"))
	if err != nil {
		t.Fatal(err)
	}
	var pin map[string]string
	if err := json.Unmarshal(raw, &pin); err != nil {
		t.Fatal(err)
	}
	if pin["package_digest"] != pkg.Digest() || pin["version"] != pkg.Metadata.Version || pin["package"] != pkg.Metadata.ID {
		t.Fatalf("stale pin %+v; digest %s", pin, pkg.Digest())
	}

	base := func() map[string]any {
		return map[string]any{
			"id": "v14", "tenant": "tenant:platform",
			"subject": map[string]any{"id": "founder-human", "type": "human", "tenant": "tenant:platform", "attributes": map[string]any{
				"principal_type_source": "authentication-derived", "tenant_source": "registration-supplied", "groups": []any{"net-kingdom-admins"},
				"assurance": map[string]any{"level": "aal2", "mfa": true, "source": "key-cape", "methods": []any{"pwd", "otp"}, "at": time.Now().Unix()},
			}},
			"resource": map[string]any{"id": "memo:bea-bind-rotation-01", "type": "decision-memo", "system": "informed-decision", "tenant": "tenant:platform"},
			"action":   "accept",
			"context": map[string]any{
				"review_group": "net-kingdom-admins", "memo_class": "bounded-execution", "intake_submitter": "nk-bind-executor",
				"approval_requester": "service:nk-bind-executor", "approval_human_control": true, "approval_action": "bounded-execution",
				"memo_version": 1, "approval_id": "706f4205-aaa7-44f6-be30-d0f57664d69c",
				"approval_binding_digest": "sha256:c8a1a9c8fb22616e3aacfb877ba7974feb5eedaed491f856a6c90719c502ebe4",
			},
		}
	}
	subject := func(d map[string]any) map[string]any { return d["subject"].(map[string]any) }
	assurance := func(d map[string]any) map[string]any {
		return subject(d)["attributes"].(map[string]any)["assurance"].(map[string]any)
	}
	ctx := func(d map[string]any) map[string]any { return d["context"].(map[string]any) }
	tests := []struct {
		name, effect, reason string
		change               func(map[string]any)
	}{
		{"executor approval accepted by founder at aal2", "allow", "present_existing_eligible", func(map[string]any) {}},
		{"read", "allow", "present_existing_eligible", func(d map[string]any) { d["action"] = "read" }},
		{"actor may not approve its own approval", "deny", "self_approval_refused", func(d map[string]any) { subject(d)["id"] = "service:nk-bind-executor" }},
		{"submitter slug may not approve", "deny", "self_approval_refused", func(d map[string]any) { subject(d)["id"] = "nk-bind-executor" }},
		{"aal1 refused", "deny", "identity_refused", func(d map[string]any) { assurance(d)["level"] = "aal1" }},
		{"stale mfa refused", "deny", "stale_mfa", func(d map[string]any) { assurance(d)["at"] = time.Now().Unix() - 901 }},
		{"other approval action refused", "deny", "approval_action_not_admitted", func(d map[string]any) { ctx(d)["approval_action"] = "rotate" }},
		{"missing approval action refused", "deny", "approval_action_not_admitted", func(d map[string]any) { delete(ctx(d), "approval_action") }},
		{"other submitter refused", "deny", "unknown_submitter", func(d map[string]any) { ctx(d)["intake_submitter"] = "state-hub" }},
		{"other class refused", "deny", "unknown_class", func(d map[string]any) { ctx(d)["memo_class"] = "decision-record" }},
		{"unregistered service requester refused", "deny", "unknown_class", func(d map[string]any) { ctx(d)["approval_requester"] = "service:other" }},
		{"v13 informed-decision requester unchanged", "allow", "attribute_eligible", func(d map[string]any) {
			ctx(d)["approval_requester"] = "informed-decision"
			ctx(d)["intake_submitter"] = "state-hub"
			ctx(d)["memo_class"] = "decision-record"
			delete(ctx(d), "approval_action")
		}},
	}
	for _, tc := range tests {
		t.Run(tc.name, func(t *testing.T) {
			d := base()
			tc.change(d)
			encoded, _ := json.Marshal(d)
			var request api.CheckRequest
			if err := json.Unmarshal(encoded, &request); err != nil {
				t.Fatal(err)
			}
			got, err := pkg.Evaluate(context.Background(), request)
			if err != nil {
				t.Fatal(err)
			}
			if string(got.Effect) != tc.effect || got.Reason != tc.reason {
				t.Fatalf("got %s %s; want %s %s", got.Effect, got.Reason, tc.effect, tc.reason)
			}
		})
	}
}

// A present-existing registry row is skipped by the generated sets: it is
// admitted only by the owner-authored present_existing_profiles.
func TestAdmissionGeneratorSkipsPresentExistingRows(t *testing.T) {
	root := repoRoot(t)
	dir := t.TempDir()
	registry := filepath.Join(dir, "submitters.json")
	body := `{
	  "system:serviceaccount:sso:nk-bind-executor": {
	    "submitter_id": "nk-bind-executor",
	    "memo_classes": ["bounded-execution"],
	    "review_groups": ["net-kingdom-admins"],
	    "daily_limit": 10,
	    "present_existing": {"approval_actor": "service:nk-bind-executor", "actions": ["bounded-execution"]}
	  }
	}`
	if err := os.WriteFile(registry, []byte(body), 0o644); err != nil {
		t.Fatal(err)
	}
	check := exec.Command("python3", filepath.Join(root, "tools/gen_informed_decision_admission.py"),
		"--source", registry, "--policy", sittingPolicyPath(t), "--check")
	if out, err := check.CombinedOutput(); err != nil || !strings.Contains(string(out), "0 submitters, 0 classes; in sync") {
		t.Fatalf("present-existing row changed the generated sets: %v\n%s", err, out)
	}
}