package controller

import (
	"context"
	"net/http/httptest"

	. "github.com/onsi/ginkgo/v2"
	. "github.com/onsi/gomega"
	"k8s.io/apimachinery/pkg/api/meta"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/types"
	"sigs.k8s.io/controller-runtime/pkg/reconcile"

	terdutv1alpha1 "git.ryuvia.com/niklas/terdut-operator/api/v1alpha1"
	"git.ryuvia.com/niklas/terdut-operator/internal/tdclient"
)

var _ = Describe("TerdutEscalationRule Controller", func() {
	const operatorNamespace = "default"

	var (
		reconciler *TerdutEscalationRuleReconciler
		fake       *fakeTerdutServer
		fakeSrv    *httptest.Server
		srv        *terdutv1alpha1.TerdutServer
		team       *terdutv1alpha1.TerdutTeam
		ruleName   string
		ruleKey    types.NamespacedName
	)

	BeforeEach(func(ctx SpecContext) {
		fake, fakeSrv = newFakeTerdutServer()
		DeferCleanup(fakeSrv.Close)

		srv = bootstrapReadyTerdutServer(ctx, uniqueName("erserver"), fakeSrv.URL)
		team = readyTerdutTeam(ctx, operatorNamespace, uniqueName("erteam"), srv, fakeSrv.URL)

		reconciler = &TerdutEscalationRuleReconciler{
			Client:            k8sClient,
			Scheme:            k8sClient.Scheme(),
			OperatorNamespace: operatorNamespace,
			NewClient:         func(string) *tdclient.Client { return tdclient.New(fakeSrv.URL) },
		}
		ruleName = uniqueName("escalation")
		ruleKey = types.NamespacedName{Name: ruleName, Namespace: operatorNamespace}
	})

	AfterEach(func(ctx SpecContext) {
		rule := &terdutv1alpha1.TerdutEscalationRule{}
		if err := k8sClient.Get(ctx, ruleKey, rule); err == nil {
			rule.Finalizers = nil
			_ = k8sClient.Update(ctx, rule)
			_ = k8sClient.Delete(ctx, rule)
		}

		// team/srv carry their own finalizers from readyTerdutTeam/
		// bootstrapReadyTerdutServer -- clear them directly the same way
		// terdutteam_controller_test.go's own AfterEach does, rather than
		// relying on either reconciler to ever run again here.
		teamKey := types.NamespacedName{Name: team.Name, Namespace: operatorNamespace}
		if err := k8sClient.Get(ctx, teamKey, team); err == nil {
			team.Finalizers = nil
			_ = k8sClient.Update(ctx, team)
			_ = k8sClient.Delete(ctx, team)
		}

		srvKey := types.NamespacedName{Name: srv.Name, Namespace: operatorNamespace}
		if err := k8sClient.Get(ctx, srvKey, srv); err == nil {
			srv.Finalizers = nil
			_ = k8sClient.Update(ctx, srv)
			_ = k8sClient.Delete(ctx, srv)
		}
	})

	createRule := func(ctx context.Context, teamRef terdutv1alpha1.TerdutTeamRef, levels []terdutv1alpha1.EscalationLevel) {
		rule := &terdutv1alpha1.TerdutEscalationRule{
			ObjectMeta: metav1.ObjectMeta{Name: ruleName, Namespace: operatorNamespace},
			Spec: terdutv1alpha1.TerdutEscalationRuleSpec{
				TeamRef: teamRef,
				Levels:  levels,
			},
		}
		Expect(k8sClient.Create(ctx, rule)).To(Succeed())
	}

	reconcileOnce := func(ctx context.Context) {
		_, err := reconciler.Reconcile(ctx, reconcile.Request{NamespacedName: ruleKey})
		Expect(err).NotTo(HaveOccurred())
	}

	readyCondition := func(ctx context.Context) metav1.Condition {
		rule := &terdutv1alpha1.TerdutEscalationRule{}
		Expect(k8sClient.Get(ctx, ruleKey, rule)).To(Succeed())
		c := meta.FindStatusCondition(rule.Status.Conditions, terdutv1alpha1.ConditionReady)
		Expect(c).NotTo(BeNil())
		return *c
	}

	sameTeamRef := func() terdutv1alpha1.TerdutTeamRef {
		return terdutv1alpha1.TerdutTeamRef{Name: team.Name}
	}

	Describe("the happy path", func() {
		It("resolves usernames and applies the escalation policy", func(ctx SpecContext) {
			fake.seedUser("alice")
			createRule(ctx, sameTeamRef(), []terdutv1alpha1.EscalationLevel{
				{Timeout: "5m", Targets: []terdutv1alpha1.EscalationTarget{
					{Kind: terdutv1alpha1.EscalationTargetUser, Username: "alice"},
				}},
				{Timeout: "10m", Targets: []terdutv1alpha1.EscalationTarget{
					{Kind: terdutv1alpha1.EscalationTargetOncall},
				}},
			})
			reconcileOnce(ctx) // finalizer
			reconcileOnce(ctx) // resolve + apply

			cond := readyCondition(ctx)
			Expect(cond.Status).To(Equal(metav1.ConditionTrue))
			Expect(cond.Reason).To(Equal(terdutv1alpha1.ReasonChildAdopted))

			applied, ok := fake.escalation[team.Status.TeamID]
			Expect(ok).To(BeTrue())
			Expect(applied.Levels).To(HaveLen(2))
			Expect(applied.Levels[0].Targets[0].Kind).To(Equal("user"))
			Expect(applied.Levels[0].Targets[0].UserID).NotTo(BeNil())
			Expect(*applied.Levels[0].Targets[0].UserID).To(Equal(fake.users["alice"]))
			Expect(applied.Levels[1].Targets[0].Kind).To(Equal("oncall"))
			Expect(applied.Levels[1].Targets[0].UserID).To(BeNil())
		})
	})

	Describe("an unresolvable username", func() {
		It("reports UnknownUser and never calls PUT /api/teams/{id}/escalation", func(ctx SpecContext) {
			createRule(ctx, sameTeamRef(), []terdutv1alpha1.EscalationLevel{
				{Timeout: "5m", Targets: []terdutv1alpha1.EscalationTarget{
					{Kind: terdutv1alpha1.EscalationTargetUser, Username: "ghost"},
				}},
			})
			reconcileOnce(ctx) // finalizer
			reconcileOnce(ctx)

			cond := readyCondition(ctx)
			Expect(cond.Status).To(Equal(metav1.ConditionFalse))
			Expect(cond.Reason).To(Equal(terdutv1alpha1.ReasonUnknownUser))
			_, applied := fake.escalation[team.Status.TeamID]
			Expect(applied).To(BeFalse())
		})
	})

	Describe("waiting on the referenced TerdutTeam", func() {
		It("reports TeamRefNotFound when the TerdutTeam doesn't exist", func(ctx SpecContext) {
			createRule(ctx, terdutv1alpha1.TerdutTeamRef{Name: testRefNotFoundName}, []terdutv1alpha1.EscalationLevel{
				{Timeout: "5m", Targets: []terdutv1alpha1.EscalationTarget{{Kind: terdutv1alpha1.EscalationTargetOncall}}},
			})
			reconcileOnce(ctx) // finalizer
			reconcileOnce(ctx)

			Expect(readyCondition(ctx).Reason).To(Equal(terdutv1alpha1.ReasonTeamRefNotFound))
		})

		It("reports WaitingForTeam when the TerdutTeam exists but isn't Ready yet", func(ctx SpecContext) {
			unreadyName := uniqueName("erteam-unready")
			unready := &terdutv1alpha1.TerdutTeam{
				ObjectMeta: metav1.ObjectMeta{Name: unreadyName, Namespace: operatorNamespace},
				Spec: terdutv1alpha1.TerdutTeamSpec{
					ServerRef:   terdutv1alpha1.TerdutServerRef{Name: srv.Name},
					DisplayName: testUnreadyDisplayName,
				},
			}
			Expect(k8sClient.Create(ctx, unready)).To(Succeed())
			DeferCleanup(func() { _ = k8sClient.Delete(ctx, unready) })

			createRule(ctx, terdutv1alpha1.TerdutTeamRef{Name: unreadyName}, []terdutv1alpha1.EscalationLevel{
				{Timeout: "5m", Targets: []terdutv1alpha1.EscalationTarget{{Kind: terdutv1alpha1.EscalationTargetOncall}}},
			})
			reconcileOnce(ctx) // finalizer
			reconcileOnce(ctx)

			Expect(readyCondition(ctx).Reason).To(Equal(terdutv1alpha1.ReasonWaitingForTeam))
		})
	})

	Describe("deletion", func() {
		It("PUTs an empty policy (this resource's only available undo) and removes the finalizer", func(ctx SpecContext) {
			fake.seedUser("alice")
			createRule(ctx, sameTeamRef(), []terdutv1alpha1.EscalationLevel{
				{Timeout: "5m", Targets: []terdutv1alpha1.EscalationTarget{
					{Kind: terdutv1alpha1.EscalationTargetUser, Username: "alice"},
				}},
			})
			reconcileOnce(ctx)
			reconcileOnce(ctx)
			Expect(readyCondition(ctx).Status).To(Equal(metav1.ConditionTrue))
			Expect(fake.escalation[team.Status.TeamID].Levels).To(HaveLen(1))

			rule := &terdutv1alpha1.TerdutEscalationRule{}
			Expect(k8sClient.Get(ctx, ruleKey, rule)).To(Succeed())
			Expect(k8sClient.Delete(ctx, rule)).To(Succeed())
			reconcileOnce(ctx) // runs the finalizer

			Expect(fake.escalation[team.Status.TeamID].Levels).To(BeEmpty())
			err := k8sClient.Get(ctx, ruleKey, rule)
			Expect(err).To(HaveOccurred(), "the TerdutEscalationRule itself should be gone once the finalizer clears")
		})
	})
})