package main

import (
	"context"
	"strings"
	"testing"
	"time"

	"github.com/novox/mesh-controller/internal/catalogue"
	"github.com/novox/mesh-controller/internal/inventory"
	"github.com/novox/mesh-controller/internal/link"
)

// TestAWalkLeavesOutAModuleWhoseProgramDidNotChange is novox/hq issue 721: mesh-controller #335 changed one sentence
// that mesh-builder never reaches; its check found build-agent the same as the build the mesh holds, so the walk moves
// mesh-controller alone and says build-agent is unchanged.
func TestAWalkLeavesOutAModuleWhoseProgramDidNotChange(t *testing.T) {
	pull := link.PullRef{Owner: "novox", Repo: "mesh-controller", Number: 335}
	head := "34050dc6aaaabbbbccccdddd"
	aPlan := func() *inventory.Plan {
		return &inventory.Plan{Tiers: [][]string{{"mesh-controller", "build-agent"}},
			Modules: map[string]*inventory.PlanModule{"mesh-controller": {}, "build-agent": {}},
			Delivery: &inventory.PlanDelivery{Merges: []inventory.PlanMerge{{Repository: "novox/mesh-controller",
				Commit: "c2ec0a60", Number: 335, Head: head}}}}
	}
	held := map[string]string{"build-agent/agent": "store/build-agent@sha256:aaaa",
		"mesh-controller/controller": "store/mesh-controller@sha256:cccc"}
	builds := []link.CheckedBuild{
		{Pull: pull, Head: head[:12], Built: link.CheckBuilt{Module: "build-agent", Key: "k1",
			Made:   []link.MadeArtifact{{Name: "agent", Kind: "image", Reference: "scratch/build-agent@sha256:bbbb"}},
			Same:   "unchanged: its program is the same as running build agent aaaa",
			SameAs: map[string]string{"agent": "10.0.0.1:5000/build-agent@sha256:aaaa"}}},
		{Pull: pull, Head: head[:12], Built: link.CheckBuilt{Module: "mesh-controller", Key: "k2",
			Made: []link.MadeArtifact{{Name: "controller", Kind: "image", Reference: "scratch/mesh-controller@sha256:dddd"}}}},
	}

	p := aPlan()
	same := sameAsRunning(p, builds, held)
	if len(same) != 1 || same["build-agent"] == "" {
		t.Fatalf("the walk leaves out %v, want build-agent alone", same)
	}
	withhold(p, []string{"build-agent"}, nil)
	if len(p.Tiers) != 1 || len(p.Tiers[0]) != 1 || p.Tiers[0][0] != "mesh-controller" {
		t.Fatalf("the walk moves %v, want mesh-controller alone", p.Tiers)
	}

	// **The held build moved since the check**: what it was compared with no longer runs.
	moved := map[string]string{"build-agent/agent": "store/build-agent@sha256:eeee"}
	if same := sameAsRunning(aPlan(), builds, moved); len(same) != 0 {
		t.Fatalf("a module compared with a build the mesh no longer holds is left out: %v", same)
	}
	// **A check of another head** says nothing of this merge.
	other := aPlan()
	other.Delivery.Merges[0].Head = "ffffffffffffffff"
	if same := sameAsRunning(other, builds, held); len(same) != 0 {
		t.Fatalf("a check of another head left out %v", same)
	}
	// **Another pull request the walk answers** that did not find it the same leaves it in.
	two := aPlan()
	two.Delivery.Merges = append(two.Delivery.Merges, inventory.PlanMerge{Repository: "novox/mesh-catalog",
		Commit: "1234", Number: 9, Head: "abcdefabcdefabcdef"})
	if same := sameAsRunning(two, builds, held); len(same) != 0 {
		t.Fatalf("a module another merge moves is left out: %v", same)
	}
	// **A merge with no pull request** leaves the walk as it is.
	direct := aPlan()
	direct.Delivery.Merges[0].Number = 0
	if same := sameAsRunning(direct, builds, held); len(same) != 0 {
		t.Fatalf("a walk answering a merge without a pull request left out %v", same)
	}
}

// TestADependentOfABaseThatCameOutTheSameIsLeftOut is ADR 0267 rule 3 (novox/hq issue 607): a dependent is in a walk
// for its base; when the base comes out the same as the build the mesh holds, the dependent stands on that build
// still, and leaves the walk with it — and so does a dependent of that dependent. One a merge moves itself stays.
func TestADependentOfABaseThatCameOutTheSameIsLeftOut(t *testing.T) {
	edges := []inventory.Edge{{From: "app", To: "base", Kind: inventory.EdgeDeclared},
		{From: "app2", To: "app", Kind: inventory.EdgeDeclared}, {From: "own", To: "base", Kind: inventory.EdgeDeclared}}
	plan := &inventory.Plan{Modules: map[string]*inventory.PlanModule{"base": {}, "app": {}, "app2": {}, "own": {}}}
	same := withDependentsOf(map[string]string{"base": "unchanged: its program is the same"}, plan,
		[]string{"base", "own"}, edges)
	if !strings.Contains(same["app"], "only for base") || !strings.Contains(same["app2"], "only for app") {
		t.Fatalf("the dependents of a base that came out the same are not left out: %v", same)
	}
	if _, left := same["own"]; left {
		t.Fatalf("a module its merge moves itself is left out for its base: %v", same)
	}
	// A dependent of a base that still moves stays.
	edges = append(edges, inventory.Edge{From: "app", To: "own", Kind: inventory.EdgeDeclared})
	same = withDependentsOf(map[string]string{"base": "unchanged"}, plan, []string{"base", "own"}, edges)
	if _, left := same["app"]; left {
		t.Fatalf("a dependent of a base that still moves is left out: %v", same)
	}
}

// Against the store, the path a real merge takes (novox/hq issues 721 and 611): a merge whose check built its one
// module the same as the build the mesh holds is cut into a walk done with nothing to walk, whose record names the
// module unchanged and why — the walk mesh-delivery reads as delivered, never stranded.
func TestAWalkWhoseEveryBuildCameOutTheSameIsDone(t *testing.T) {
	open := windowed(t)
	endsItsLine(t)
	asksRecorded(t)
	ctx := t.Context()
	inv := open.inventory
	if err := inv.RecordBuild(ctx, inventory.Build{ID: "build-one", Repository: "novox/one", Ref: "main",
		Module: "one", Commit: "c0", On: "builder", Asked: t0.Add(-time.Hour),
		Made:    []inventory.Artifact{{Name: "one", Kind: "image", Reference: "store/one@sha256:aaaa"}},
		Sources: []inventory.BuildSource{{Paths: []string{"main.go", "go.mod"}}}}); err != nil {
		t.Fatal(err)
	}
	// What runs: the module registered with that build's image (RegisteredHeld reads the module table).
	if err := inv.RegisterModule(ctx, catalogue.Manifest{Module: "one", Version: "1", Resources: []map[string]any{
		{"id": "app", "type": "container", "name": "one", "image": "store/one@sha256:aaaa"}}},
		inventory.Source{Repository: "novox/one", Ref: "main", BuiltFrom: "c0", Asked: time.Now()}); err != nil {
		t.Fatal(err)
	}
	pull := link.PullRef{Owner: "novox", Repo: "one", Number: 7}
	was := checkedBuildsOf
	checkedBuildsOf = func(context.Context, []link.PullRef) ([]link.CheckedBuild, error) {
		return []link.CheckedBuild{{Pull: pull, Head: "headaaaaaaaa", Built: link.CheckBuilt{Module: "one", Key: "k",
			Made:   []link.MadeArtifact{{Name: "one", Kind: "image", Reference: "scratch/one@sha256:bbbb"}},
			Same:   "unchanged: its program is the same as running build one aaaa",
			SameAs: map[string]string{"one": "10.0.0.1:5000/one@sha256:aaaa"}}}}, nil
	}
	t.Cleanup(func() { checkedBuildsOf = was })
	code := repoMerge("one", "one1aaaaaaaa", t0)
	code.Number, code.HeadSHA = 7, "headaaaaaaaa1111"
	hear(t, open, code, t0.Add(time.Second))
	cutAt(t, open, t0.Add(2*time.Minute))
	ws, _ := walks(t, open)
	if len(ws) != 1 {
		t.Fatalf("walks: %+v", ws)
	}
	w := ws[0]
	if w.State != inventory.PlanDone || len(w.Tiers) != 0 || len(w.Modules) != 0 {
		t.Fatalf("the walk reads %s, tiers %v, modules %v; want done with nothing to walk", w.State, w.Tiers, w.Modules)
	}
	if w.Delivery == nil || !strings.Contains(w.Delivery.Unchanged["one"], "its program is the same as running build") {
		t.Fatalf("the walk does not say one matched what runs: %+v", w.Delivery)
	}
}