package build

import (
	"context"
	"encoding/json"
	"errors"
	"fmt"
	"git.novox.be/novox/mesh-sdk/go/delivery/buildrun"
	"strings"
	"sync"
	"testing"
	"time"

	"git.novox.be/novox/mesh-sdk/go/buildstep"
	"git.novox.be/novox/mesh-sdk/go/catalogue"
	"git.novox.be/novox/mesh-sdk/go/delivery"
)

// buildModules simulates the two build modules on the nodes: a long tool answers a step and key at once and writes the
// step's end into the steps (as mesh-build-go and mesh-build-node do), with a digest by node and artifact, or a failure.
type buildModules struct {
	mu      sync.Mutex
	n       int
	calls   []call
	steps   *fakeSteps
	digests map[string]string // `<node>/<artifact>` -> digest; the default is `digest`
	fails   map[string]string // `<node>/<tool>` -> the reason the step fails with
	// noRef names `<node>/<artifact>` whose bundle or archive build answers no reference (its push not answered).
	noRef map[string]bool
	// packages are the package artifacts by name, each with the `<name>@<version>` its trunk build publishes (ADR 0498 clause 5).
	packages map[string]string
	// hold, when set before the builds start, blocks every call until it is closed; entered is sent to as a call arrives.
	// conflicts, when set, is a file a fetch with a base reports in conflict; noMerge makes it answer neither a merge nor a conflict.
	conflicts string
	noMerge   bool
	hold      chan struct{}
	entered   chan struct{}
}

func newBuildModules() *buildModules {
	return &buildModules{steps: &fakeSteps{steps: map[string]delivery.Step{}}, digests: map[string]string{}, fails: map[string]string{}, noRef: map[string]bool{}, packages: map[string]string{}}
}

func (b *buildModules) CallOn(node, key string, body any) (json.RawMessage, error) {
	if b.hold != nil {
		select {
		case b.entered <- struct{}{}:
		default:
		}
		<-b.hold
	}
	b.mu.Lock()
	defer b.mu.Unlock()
	b.calls = append(b.calls, call{node, key, body})
	b.n++
	id := fmt.Sprintf("s%d", b.n)
	module, tool, _ := strings.Cut(key, ".")
	args, _ := body.(map[string]any)
	step := delivery.Step{ID: id, Tool: tool, Node: node, State: delivery.StepPassed}
	if reason, ok := b.fails[node+"/"+tool]; ok {
		step.State, step.Reason = delivery.StepFailed, reason
	} else if strings.HasSuffix(tool, "_fetch") {
		step.Result = json.RawMessage(`{"workspace":"w-` + node + `"}`)
		if args["base"] != nil { // a fetch with a base answers the merge, or the files in conflict (mesh-build-go FetchResult)
			if b.conflicts != "" {
				step.Result = json.RawMessage(`{"workspace":"w-` + node + `","base":"` + fmt.Sprint(args["base"]) + `","conflicts":["` + b.conflicts + `"]}`)
			} else if !b.noMerge {
				step.Result = json.RawMessage(`{"workspace":"w-` + node + `","base":"` + fmt.Sprint(args["base"]) + `","merge":"` + strings.Repeat("9", 40) + `"}`)
			}
		}
	} else {
		d := digest
		if v, ok := b.digests[node+"/"+fmt.Sprint(args["artifact"])]; ok {
			d = v
		}
		if tool == "build_image_copy" { // mesh-build-image's copy answers the digest and where it copied to (ADR 0498 clause 4)
			step.Result = json.RawMessage(`{"artifact":"` + fmt.Sprint(args["artifact"]) + `","digest":"` + d + `","reference":"registry.example/` + fmt.Sprint(args["module"]) + `/` + fmt.Sprint(args["artifact"]) + `@` + d + `","pushed":true}`)
		} else if pkg, ok := b.packages[fmt.Sprint(args["artifact"])]; ok { // a package names its version only when published
			step.Result = json.RawMessage(`{"digest":"` + d + `"}`)
			if args["publish"] == true {
				step.Result = json.RawMessage(`{"digest":"` + d + `","reference":"` + pkg + `"}`)
			}
		} else if tool == "build_image_build" && args["publish"] == true {
			step.Result = json.RawMessage(`{"digest":"` + d + `","reference":"registry.example/m/` + fmt.Sprint(args["artifact"]) + `@` + d + `"}`)
		} else if tool != "build_image_build" && !b.noRef[node+"/"+fmt.Sprint(args["artifact"])] {
			// A bundle or an archive is pushed to the artifact store and its reference answered (ADR 0498 clause 1).
			step.Result = json.RawMessage(`{"digest":"` + d + `","reference":"artifact-store://m/` + fmt.Sprint(args["artifact"]) + `/blobs/` + d + `"}`)
		} else {
			step.Result = json.RawMessage(`{"digest":"` + d + `"}`)
		}
	}
	sk, _ := delivery.StepKey(node, id)
	b.steps.mu.Lock()
	b.steps.steps[module+"/"+sk] = step
	b.steps.mu.Unlock()
	return json.RawMessage(`{"step":"` + id + `","key":"` + sk + `","state":"running"}`), nil
}

func (b *buildModules) callsOf(tool string) (out []call) {
	b.mu.Lock()
	defer b.mu.Unlock()
	for _, c := range b.calls {
		if strings.HasSuffix(c.key, "."+tool) {
			out = append(out, c)
		}
	}
	return out
}

type fakeManifests struct {
	byDigest map[string]catalogue.Manifest
}

func (f *fakeManifests) Manifest(_ context.Context, d string) (catalogue.Manifest, error) {
	m, ok := f.byDigest[d]
	if !ok {
		return catalogue.Manifest{}, fmt.Errorf("manifests.%s is not there", d)
	}
	return m, nil
}

func mdigest(c byte) string { return hex64(c) }

type rig struct {
	b     *Builder
	st    *memStore
	bm    *buildModules
	tools *buildrun.ToolchainSet
	mf    *fakeManifests
	key   string
	// asks are the build seats' streams; puller is the node that pulls every ask ("ace" when empty).
	asks   *buildrun.FakeAsks
	puller string
}

// toolPrefix is the start of each build module's tool names, as the fake build modules answer them.
var toolPrefix = map[string]string{buildrun.GoBuildModule: "build_go_", buildrun.NodeBuildModule: "build_node_", ImageBuildModule: "build_image_"}

// answer runs an ask as the build module that pulls it does (buildstep.RunAsk), with the fake build modules' tools on the
// rig's pulling node, and answers the step that node writes.
func (r *rig) answer(a delivery.StepAsk) delivery.Step {
	node := r.puller
	if node == "" {
		node = "ace"
	}
	module, _ := delivery.BuildModuleOf(a.Language)
	runner := buildrun.Runner{Caller: r.bm, Steps: r.bm.steps, Bound: time.Second}
	tool := func(name string) buildstep.StepFunc {
		return func(ctx context.Context, args map[string]any) (any, error) {
			raw, err := runner.Run(ctx, module, node, toolPrefix[module]+name, args)
			if err != nil {
				return nil, err
			}
			return raw, nil
		}
	}
	steps := buildstep.AskSteps{Fetch: tool("fetch"), Build: tool("build"), Copy: tool("copy")}
	out, err := buildstep.RunAsk(context.Background(), steps, a)
	step := delivery.Step{ID: a.ID, Tool: a.Kind + " ask", Node: node, State: delivery.StepPassed}
	if err != nil {
		step.State, step.Reason = delivery.StepFailed, err.Error()
		return step
	}
	step.Result, _ = json.Marshal(out)
	return step
}

func newRig(t *testing.T, artifacts ...catalogue.Artifact) *rig {
	t.Helper()
	r := &rig{st: newMem(), bm: newBuildModules(), tools: &buildrun.ToolchainSet{}, mf: &fakeManifests{byDigest: map[string]catalogue.Manifest{mdigest('a'): {Module: "m", Build: &catalogue.Build{Artifacts: artifacts}}}}}
	for _, n := range []string{"ace", "novox"} {
		r.tools.Put(buildrun.GoBuildModule, n+".go", tcValue(t, "go", "go1.27.1"), false)
		r.tools.Put(buildrun.NodeBuildModule, n+".typescript", tcValue(t, "typescript", "tsc5"), false)
	}
	r.asks = &buildrun.FakeAsks{Answer: r.answer}
	r.b = &Builder{
		Claimer: Claimer{Store: r.st, By: "novox.builder"}, Asks: buildrun.Asker{Publisher: r.asks, Waiter: r.asks, Bound: 2 * time.Second},
		Toolchains: r.tools, Manifests: r.mf, Logf: t.Logf,
	}
	var err error
	if r.key, err = delivery.BuilderBuildKey("m", fp1); err != nil {
		t.Fatal(err)
	}
	return r
}

// agreedToolchains are what the rig's nodes report, and so what a fingerprint computed now names.
var agreedToolchains = map[string]delivery.ToolchainUsed{"go": {Version: "go1.27.1", Recipe: "1"}, "typescript": {Version: "tsc5", Recipe: "1"}}

func moduleValue(t *testing.T, path string) []byte { return moduleValueWith(t, path, agreedToolchains) }

func moduleValueWith(t *testing.T, path string, toolchains map[string]delivery.ToolchainUsed) []byte {
	t.Helper()
	data, err := delivery.EncodeModule(delivery.Module{Repository: "novox/mesh-catalog", Commit: "7a74cee83f88e6585a5511c3cc53bdf0f5303d20", FP: "src1:" + hex64('f'), FP2: fp1, Manifest: mdigest('a'), Path: path, Toolchains: toolchains})
	if err != nil {
		t.Fatal(err)
	}
	return data
}

func (r *rig) consider(t *testing.T, path string) delivery.BuilderBuild {
	t.Helper()
	r.b.Module(context.Background(), "m", moduleValue(t, path))
	r.b.Wait()
	if _, ok := r.st.vals[r.key]; !ok {
		t.Fatal("no build key was written")
	}
	return valueOf(t, r.st, r.key)
}

var (
	goBundle  = catalogue.Artifact{Name: "tool", Kind: "bundle", Language: "go"}
	tsBundle  = catalogue.Artifact{Name: "web", Kind: "bundle", Language: "typescript"}
	archiveA  = catalogue.Artifact{Name: "files", Kind: "archive"}
	imageArt  = catalogue.Artifact{Name: "img", Kind: "image"}
	manifestD = mdigest('a')
)

func TestABundleAndAnArchiveAreBuiltOnOneNodeAndDone(t *testing.T) { // 1607/AC7, ADR 0478 clauses 1, 4
	r := newRig(t, goBundle, archiveA, tsBundle)
	v := r.consider(t, "modules/m")
	if v.State != delivery.BuildDone || v.By != "novox.builder" || v.Manifest != manifestD || len(v.Artifacts) != 3 {
		t.Fatalf("build = %+v, want done by novox.builder with three artifacts", v)
	}
	for i, want := range []string{"files", "tool", "web"} {
		if a := v.Artifacts[i]; a.Name != want || a.Digest != digest || a.Reference != "artifact-store://m/"+want+"/blobs/"+digest {
			t.Errorf("artifact %d = %+v, want %s with the digest and its artifact-store reference (ADR 0498 clause 1)", i, a, want)
		}
	}
	if v.Artifacts[0].Kind != "archive" || v.Artifacts[1].Kind != "bundle" {
		t.Errorf("kinds = %+v", v.Artifacts)
	}
	if got := v.Toolchains["go"]; got.Version != "go1.27.1" || got.Recipe != "1" {
		t.Errorf("toolchains = %+v, want go and typescript named", v.Toolchains)
	}
	if got := v.Toolchains["typescript"]; got.Version != "tsc5" {
		t.Errorf("toolchains = %+v", v.Toolchains)
	}
	// One fetch per build module, on one node (ADR 0478 clause 4); every build names the module's directory.
	if n := len(r.bm.callsOf("build_go_fetch")); n != 1 {
		t.Errorf("%d go fetches, want one", n)
	}
	if n := len(r.bm.callsOf("build_go_build")); n != 2 { // tool and files
		t.Errorf("%d go builds, want 2", n)
	}
	if n := len(r.bm.callsOf("build_node_build")); n != 1 {
		t.Errorf("%d node builds, want 1", n)
	}
	c := r.bm.callsOf("build_go_build")[0]
	if args := c.body.(map[string]any); args["module"] != "modules/m" || !strings.HasPrefix(fmt.Sprint(args["workspace"]), "w-") {
		t.Errorf("build args = %+v, want the module's path and the fetch's workspace", args)
	}
	f := r.bm.callsOf("build_go_fetch")[0].body.(map[string]any)
	if f["repository"] != "novox/mesh-catalog" || f["commit"] != "7a74cee83f88e6585a5511c3cc53bdf0f5303d20" {
		t.Errorf("fetch args = %+v", f)
	}
}

// 1887/AC1, AC2: a trunk fingerprint with no key is one ask on the Go seat's delivery stream, named in the building key
// before it is put, and the builder calls no node; the step a node wrote for it makes the key done naming its reference.
func TestATrunkFingerprintIsOneAskOnTheDeliveryStream(t *testing.T) {
	r := newRig(t, goBundle)
	r.asks.Answer = nil // no node has pulled it yet
	r.b.Module(context.Background(), "m", moduleValue(t, "modules/m"))
	var asks []delivery.StepAsk
	for deadline := time.Now().Add(2 * time.Second); len(asks) == 0; time.Sleep(time.Millisecond) {
		if time.Now().After(deadline) {
			t.Fatal("no ask was put")
		}
		asks = r.asks.Asks()
	}
	a := asks[0]
	if len(asks) != 1 || a.Kind != delivery.AskDelivery || a.Language != delivery.AskGo || a.Build == nil || a.Build.FP != fp1 {
		t.Fatalf("asks = %+v, want one Go delivery ask of the fingerprint", asks)
	}
	if v := valueOf(t, r.st, r.key); v.State != delivery.BuildBuilding || v.Asks[delivery.AskGo] != a.ID {
		t.Fatalf("the key = %+v, want building naming the ask %s", v, a.ID)
	}
	if n := len(r.bm.callsOf("build_go_build")) + len(r.bm.callsOf("build_go_fetch")); n != 0 {
		t.Fatalf("the builder called a node %d times", n)
	}
	r.asks.End(r.answer(a)) // a node pulled it and ran it
	r.b.Wait()
	if v := valueOf(t, r.st, r.key); v.State != delivery.BuildDone || !strings.Contains(v.Step, "on ace") || v.Artifacts[0].Reference == "" || len(v.Asks) != 0 {
		t.Fatalf("the key = %+v, want done on ace naming the reference", v)
	}
}

// 1887/AC3: a builder that starts again while its ask waits puts no second ask: it waits for the step of the ask the
// building key names.
func TestARestartedBuilderWaitsForTheAskTheKeyNames(t *testing.T) {
	r := newRig(t, goBundle)
	const id = "mvl0frv18d1957"
	data, _ := delivery.EncodeBuilderBuild(delivery.BuilderBuild{State: delivery.BuildBuilding, By: "novox.builder", Manifest: manifestD,
		Step: "asked mesh-build-go", Asks: map[string]string{delivery.AskGo: id}})
	r.st.vals[r.key] = data
	r.asks.Answer = nil
	r.asks.End(delivery.Step{ID: id, Node: "shanks", State: delivery.StepPassed,
		Result: []byte(`{"artifacts":[{"artifact":"tool","digest":"` + digest + `","reference":"artifact-store://m/tool/blobs/` + digest + `"}]}`)})
	v := r.consider(t, "modules/m")
	if n := len(r.asks.Asks()); n != 0 {
		t.Fatalf("%d asks put again", n)
	}
	if v.State != delivery.BuildDone || !strings.Contains(v.Step, "on shanks") {
		t.Fatalf("the key = %+v, want done from the ask's step on shanks", v)
	}
}

func TestAFailingStepFailsTheBuildWithItsReasonAndNodeAndIsTriedAgainAsANewRevision(t *testing.T) { // 1607/AC7, ADR 0429 clause 18
	r := newRig(t, goBundle)
	r.bm.fails["ace/build_go_build"] = "go build of tool: undefined: x"
	v := r.consider(t, "modules/m")
	if v.State != delivery.BuildFailed || !strings.Contains(v.Error, "ace") || !strings.Contains(v.Error, "undefined: x") {
		t.Fatalf("build = %+v, want failed with the node and the reason", v)
	}
	rev := r.st.revs[r.key]
	delete(r.bm.fails, "ace/build_go_build")
	v = r.consider(t, "modules/m")
	if v.State != delivery.BuildDone || r.st.revs[r.key] <= rev {
		t.Errorf("build = %+v at revision %d (was %d), want done as a new revision of the same key", v, r.st.revs[r.key], rev)
	}
}

func TestAnImageGoesToOneNodeAndGetsOneDoneKeyWithItsReference(t *testing.T) { // 1705a, ADR 0487 clause 5
	r := newRig(t, imageArt)
	r.puller = "ace" // two nodes qualify; an image still builds on one
	v := r.consider(t, "modules/m")
	if v.State != delivery.BuildDone || len(v.Artifacts) != 1 || v.Artifacts[0].Kind != "image" || v.Artifacts[0].Digest != digest {
		t.Fatalf("build = %+v, want done with one image artifact and its digest", v)
	}
	if v.Artifacts[0].Reference == "" {
		t.Errorf("a trunk image has no reference: %+v", v.Artifacts[0])
	}
	if n := len(r.bm.callsOf("build_image_fetch")); n != 1 {
		t.Errorf("%d image fetches, want one", n)
	}
	writes := r.st.writes
	r.consider(t, "modules/m")
	if r.st.writes != writes || len(r.bm.callsOf("build_image_build")) != 1 {
		t.Errorf("a done image key was built again")
	}
}

func TestABundleAndAnImageOfOneModuleBuildOnOneNodeEach(t *testing.T) { // 1705a
	r := newRig(t, goBundle, imageArt)
	r.puller = "ace"
	v := r.consider(t, "modules/m")
	if v.State != delivery.BuildDone || len(v.Artifacts) != 2 {
		t.Fatalf("build = %+v", v)
	}
	if n := len(r.bm.callsOf("build_go_build")); n != 1 {
		t.Errorf("%d go builds, want 1 (one node per fingerprint, ADR 0478 clause 4)", n)
	}
	if n := len(r.bm.callsOf("build_image_build")); n != 1 {
		t.Errorf("%d image builds, want 1", n)
	}
}

func TestACandidatesImageCallCarriesNoPublishAndItsKeyNoReference(t *testing.T) { // 1705b, lead's decision
	r := newRig(t, imageArt)
	r.puller = "ace"
	trunkModule(t, r)
	r.b.Candidate(context.Background(), "feat%2Fx", candidateValue(t, "feat/x", 7, headX))
	r.b.Wait()
	v := valueOf(t, r.st, r.key)
	if v.State != delivery.BuildDone || len(v.Artifacts) != 1 || v.Artifacts[0].Reference != "" {
		t.Fatalf("build = %+v, want done with no reference", v)
	}
	calls := r.bm.callsOf("build_image_build")
	if len(calls) != 1 {
		t.Fatalf("%d image builds, want 1", len(calls))
	}
	if _, has := calls[0].body.(map[string]any)["publish"]; has {
		t.Errorf("a candidate's image call carries publish: %+v", calls[0].body)
	}
}

func TestATrunkImageCallCarriesPublish(t *testing.T) { // 1705b
	r := newRig(t, imageArt)
	r.puller = "ace"
	r.consider(t, "modules/m")
	calls := r.bm.callsOf("build_image_build")
	if len(calls) != 1 || calls[0].body.(map[string]any)["publish"] != true {
		t.Errorf("calls = %+v, want publish true", calls)
	}
}

func TestAnUnpinnedUpstreamFailsNotPinnedAndIsNeverBuiltAgain(t *testing.T) { // B3, ADR 0498 clause 4
	r := newRig(t, archiveA, catalogue.Artifact{Name: "up", Kind: "upstream", From: "nats:2.11.17-alpine"})
	v := r.consider(t, "modules/m")
	if v.State != delivery.BuildFailed || !strings.HasPrefix(v.Error, delivery.NotPinned) || !strings.Contains(v.Error, "up") {
		t.Fatalf("build = %+v, want failed 'not pinned:' naming the artifact", v)
	}
	if len(r.bm.calls) != 0 {
		t.Errorf("%d calls, want none for an unpinned upstream", len(r.bm.calls))
	}
	writes := r.st.writes
	r.consider(t, "modules/m")
	if r.st.writes != writes {
		t.Errorf("an unpinned upstream's key was written again (%d writes, was %d)", r.st.writes, writes)
	}
}

func TestAModuleKeyWithNoPathFailsNamingThatReason(t *testing.T) { // 1607/AC8, ADR 0478 clause 8
	r := newRig(t, goBundle)
	v := r.consider(t, "")
	if v.State != delivery.BuildFailed || !strings.Contains(v.Error, "path") || len(r.bm.calls) != 0 {
		t.Errorf("build = %+v with %d calls, want failed naming the missing path and nothing called", v, len(r.bm.calls))
	}
}

func TestAnUnreadableManifestFailsTheBuild(t *testing.T) {
	r := newRig(t, goBundle)
	delete(r.mf.byDigest, mdigest('a'))
	v := r.consider(t, "modules/m")
	if v.State != delivery.BuildFailed || !strings.Contains(v.Error, "manifest") {
		t.Errorf("build = %+v, want failed naming the manifest", v)
	}
}

func TestAModuleWithNoFingerprintIsNotBuilt(t *testing.T) { // 1607/AC2
	r := newRig(t)
	data, _ := delivery.EncodeModule(delivery.Module{Repository: "novox/r", Commit: "c", FP: "src1:" + hex64('f'), None2: "toolchain not yet reported"})
	r.b.Module(context.Background(), "n", data)
	r.b.Wait()
	if len(r.st.vals) != 0 {
		t.Errorf("keys %v were written: a module with no new-form fingerprint has nothing to build", r.st.vals)
	}
}

func TestAModuleWithNoArtifactGetsADoneKeyWithNoArtifactAndNoBuildCall(t *testing.T) { // issue 1613, ADR 0478 clause 1
	for name, manifest := range map[string]catalogue.Manifest{"no build": {Module: "m"}, "no artifact": {Module: "m", Build: &catalogue.Build{}}} {
		r := newRig(t)
		r.mf.byDigest[mdigest('a')] = manifest
		v := r.consider(t, "") // a module with nothing to build needs no directory
		if v.State != delivery.BuildDone || len(v.Artifacts) != 0 || v.Manifest != manifestD || v.By != "novox.builder" {
			t.Errorf("%s: build = %+v, want done with no artifact", name, v)
		}
		if len(r.bm.calls) != 0 {
			t.Errorf("%s: %d build module calls, want none", name, len(r.bm.calls))
		}
		writes := r.st.writes
		r.b.tried = map[string]bool{}
		r.consider(t, "")
		if r.st.writes != writes {
			t.Errorf("%s: the done key was written again", name)
		}
	}
}

func TestAKeyTheBuilderLeftBuildingIsBuiltAtStartAndDoneKeysAreNotBuiltTwice(t *testing.T) { // 1607/AC3, AC7
	r := newRig(t, goBundle)
	seed(t, r.st, delivery.BuilderBuild{State: delivery.BuildBuilding, By: "novox.builder", Manifest: manifestD})
	if v := r.consider(t, "modules/m"); v.State != delivery.BuildDone {
		t.Fatalf("build = %+v, want the builder's own building key built", v)
	}
	calls := len(r.bm.calls)
	r.b.Module(context.Background(), "m", moduleValue(t, "modules/m"))
	r.b.Reconsider(context.Background())
	r.b.Wait()
	if len(r.bm.calls) != calls {
		t.Errorf("a done key was built again (%d calls, was %d)", len(r.bm.calls), calls)
	}
}

// Two instances that start together on one key: the second finds the key building and takes it over (ADR 0478 clause 6:
// a key found building at start is taken over, whoever holds it), so both may build; the key is written once, by the one
// whose compare-and-set comes first, and the other's write is refused, never overwriting it.
func TestTwoInstancesStartingTogetherEndWithOneDoneKey(t *testing.T) { // 1607/AC7, review round 4
	r := newRig(t, goBundle)
	other := &Builder{Claimer: Claimer{Store: r.st, By: "ace.builder"}, Asks: r.b.Asks, Toolchains: r.tools, Manifests: r.mf, Logf: t.Logf}
	value := moduleValue(t, "modules/m")
	var wg sync.WaitGroup
	for _, b := range []*Builder{r.b, other} {
		wg.Add(1)
		go func() { defer wg.Done(); b.Module(context.Background(), "m", value); b.Wait() }()
	}
	wg.Wait()
	if v := valueOf(t, r.st, r.key); v.State != delivery.BuildDone || len(v.Artifacts) != 1 {
		t.Errorf("build = %+v, want one done key", v)
	}
	if n := len(r.bm.callsOf("build_go_build")); n < 1 {
		t.Errorf("%d builds, want one for each instance that built", n)
	}
}

func TestAModulesValueThatArrivesWhileItsKeyIsBeingBuiltIsLookedAtAgainWhenItEnds(t *testing.T) { // 1607/AC6 (no event is dropped, no timer)
	r := newRig(t, goBundle)
	r.bm.fails["ace/build_go_build"] = "go build of tool: boom"
	r.bm.hold, r.bm.entered = make(chan struct{}), make(chan struct{}, 8)
	value := moduleValue(t, "modules/m")
	r.b.Module(context.Background(), "m", value)
	<-r.bm.entered // the first build is under way
	r.b.Module(context.Background(), "m", value)
	r.b.Reconsider(context.Background())
	delete(r.bm.fails, "ace/build_go_build") // what the event is about: the build can succeed now
	close(r.bm.hold)
	r.b.Wait()
	if v := valueOf(t, r.st, r.key); v.State != delivery.BuildDone {
		t.Errorf("build = %+v, want the failed key built again as a new revision after the first build ended", v)
	}
}

func TestAKeyIsBuiltOnlyWithTheToolchainItsFingerprintNamesAndNothingIsWrittenOtherwise(t *testing.T) { // 1615/AC4
	r := newRig(t, goBundle)
	old := map[string]delivery.ToolchainUsed{"go": {Version: "go1.26.0", Recipe: "1"}}
	r.b.Module(context.Background(), "m", moduleValueWith(t, "modules/m", old))
	r.b.Wait()
	if len(r.st.vals) != 0 || len(r.bm.calls) != 0 {
		t.Errorf("keys %v and %d calls for a fingerprint of go1.26.0 while the nodes agree on go1.27.1, want neither", r.st.vals, len(r.bm.calls))
	}
	// A recipe that differs is a different toolchain too, and a value that names none (written before) is not built.
	r.b.Module(context.Background(), "m", moduleValueWith(t, "modules/m", map[string]delivery.ToolchainUsed{"go": {Version: "go1.27.1", Recipe: "0"}}))
	r.b.Module(context.Background(), "m", moduleValueWith(t, "modules/m", nil))
	r.b.Wait()
	if len(r.st.vals) != 0 || len(r.bm.calls) != 0 {
		t.Errorf("keys %v and %d calls for a recipe that differs or a value that names no toolchain", r.st.vals, len(r.bm.calls))
	}
	// The toolchain moves under a key that is not built yet: the old fingerprint stays unbuilt, the new one builds.
	r.tools.Put(buildrun.GoBuildModule, "ace.go", tcValue(t, "go", "go1.27.2"), false)
	r.tools.Put(buildrun.GoBuildModule, "novox.go", tcValue(t, "go", "go1.27.2"), false)
	r.b.Reconsider(context.Background())
	r.b.Wait()
	if len(r.st.vals) != 0 {
		t.Errorf("keys %v: the old fingerprint was built with the new toolchain", r.st.vals)
	}
	r.b.Module(context.Background(), "m", moduleValueWith(t, "modules/m", map[string]delivery.ToolchainUsed{"go": {Version: "go1.27.2", Recipe: "1"}}))
	r.b.Wait()
	if v := valueOf(t, r.st, r.key); v.State != delivery.BuildDone || v.Toolchains["go"].Version != "go1.27.2" {
		t.Errorf("build = %+v, want done with go1.27.2", v)
	}
}

func TestNodesTheyDisagreeOnLeaveTheKeyUnwritten(t *testing.T) { // 1615/AC4
	r := newRig(t, goBundle)
	r.tools.Put(buildrun.GoBuildModule, "ace.go", tcValue(t, "go", "go1.26.0"), false)
	r.b.Module(context.Background(), "m", moduleValue(t, "modules/m"))
	r.b.Wait()
	if len(r.st.vals) != 0 || len(r.bm.calls) != 0 {
		t.Errorf("keys %v and %d calls while the nodes disagree", r.st.vals, len(r.bm.calls))
	}
}

func TestARootModulesPathIsDotAndIsGivenToTheBuildTools(t *testing.T) { // 1615/AC4
	r := newRig(t, goBundle)
	if v := r.consider(t, delivery.RootPath); v.State != delivery.BuildDone {
		t.Fatalf("build = %+v, want done for a root module", v)
	}
	if args := r.bm.callsOf("build_go_build")[0].body.(map[string]any); args["module"] != "." {
		t.Errorf("build args = %+v, want module \".\"", args)
	}
}

func TestACandidatesImageIsPublishedOnceWhenTheTrunkNamesItsFingerprint(t *testing.T) { // review r1, mesh-delivery 1; ADR 0487 clause 5
	r := newRig(t, imageArt)
	r.puller = "ace"
	trunkModule(t, r) // the trunk carries another fingerprint; fp1 is the candidate's
	r.b.Candidate(context.Background(), "feat%2Fx", candidateValue(t, "feat/x", 7, headX))
	r.b.Wait()
	v := valueOf(t, r.st, r.key)
	if v.State != delivery.BuildDone || v.Artifacts[0].Reference != "" {
		t.Fatalf("candidate build = %+v, want done with no reference", v)
	}
	if n := len(r.bm.callsOf("build_image_build")); n != 1 {
		t.Fatalf("%d image builds after the candidate, want 1", n)
	}
	// The pull request is merged: the trunk's record names the candidate's fingerprint.
	r.b.Module(context.Background(), "m", moduleValue(t, "modules/m"))
	r.b.Wait()
	v = valueOf(t, r.st, r.key)
	if v.State != delivery.BuildDone || len(v.Artifacts) != 1 || v.Artifacts[0].Reference == "" {
		t.Fatalf("trunk build = %+v, want done with a reference", v)
	}
	calls := r.bm.callsOf("build_image_build")
	published := 0
	for _, c := range calls {
		if c.body.(map[string]any)["publish"] == true {
			published++
		}
	}
	if len(calls) != 2 || published != 1 {
		t.Errorf("%d image builds, %d with publish, want 2 and exactly 1", len(calls), published)
	}
	// Written once more only: looking again builds nothing.
	rev := r.st.revs[r.key]
	r.b.Module(context.Background(), "m", moduleValue(t, "modules/m"))
	r.b.Wait()
	if r.st.revs[r.key] != rev || len(r.bm.callsOf("build_image_build")) != 2 {
		t.Error("a published key was built again")
	}
}

func TestAFailedPublishOfACandidatesImageIsWrittenToTheKey(t *testing.T) { // review r2, mesh-delivery 1; ADR 0487 clause 5
	r := newRig(t, imageArt)
	r.puller = "ace"
	trunkModule(t, r)
	r.b.Candidate(context.Background(), "feat%2Fx", candidateValue(t, "feat/x", 7, headX))
	r.b.Wait()
	if v := valueOf(t, r.st, r.key); v.State != delivery.BuildDone {
		t.Fatalf("candidate build = %+v", v)
	}
	r.bm.fails["ace/build_image_build"] = "push to the registry: connection refused"
	r.b.Module(context.Background(), "m", moduleValue(t, "modules/m")) // the merge: the trunk names the fingerprint
	r.b.Wait()
	v := valueOf(t, r.st, r.key)
	if v.State != delivery.BuildFailed || !strings.Contains(v.Error, "connection refused") || !strings.Contains(v.Error, "publish") {
		t.Fatalf("build = %+v, want failed naming the publish and its reason", v)
	}
	// The failed key is retaken as any failed key is, and ends published once the registry answers.
	delete(r.bm.fails, "ace/build_image_build")
	r.b.Module(context.Background(), "m", moduleValue(t, "modules/m"))
	r.b.Wait()
	if v := valueOf(t, r.st, r.key); v.State != delivery.BuildDone || v.Artifacts[0].Reference == "" {
		t.Errorf("build = %+v, want done with a reference", v)
	}
}

// Review round 2 item 1: a build ask that waits in its stream longer than the step bound is not failed and not asked
// again; the key is done when a node takes it.
func TestABuildAskWaitingInItsStreamIsNotBounded(t *testing.T) {
	r := newRig(t, goBundle)
	r.asks.Answer = nil
	r.b.Asks = buildrun.Asker{Publisher: r.asks, Waiter: r.asks, Bound: 20 * time.Millisecond}
	r.b.Module(context.Background(), "m", moduleValue(t, "modules/m"))
	for deadline := time.Now().Add(2 * time.Second); len(r.asks.Asks()) == 0; time.Sleep(time.Millisecond) {
		if time.Now().After(deadline) {
			t.Fatal("no ask was put")
		}
	}
	time.Sleep(100 * time.Millisecond)
	if v := valueOf(t, r.st, r.key); v.State != delivery.BuildBuilding {
		t.Fatalf("the key = %+v while its ask waits, want building", v)
	}
	r.asks.End(r.answer(r.asks.Asks()[0]))
	r.b.Wait()
	if v := valueOf(t, r.st, r.key); v.State != delivery.BuildDone || len(r.asks.Asks()) != 1 {
		t.Fatalf("the key = %+v after %d asks, want done from the one ask", v, len(r.asks.Asks()))
	}
}

// heldAsks says an ask is held when its id is among held.
type heldAsks map[string]bool

func (h heldAsks) Held(_ context.Context, a delivery.StepAsk) (bool, error) { return h[a.ID], nil }

// 1910: a builder that stopped between naming the ask in its key and putting it left a key naming an ask neither the
// stream holds nor any node ran: started again, the builder puts that ask, under the same id, once, and the key is
// built from its step; an ask the stream holds is not put again.
func TestAnAskTheKeyNamesAndNobodyPutIsPutAtStart(t *testing.T) {
	for _, held := range []bool{false, true} {
		r := newRig(t, goBundle)
		const id = "mvl0frv18d1958"
		data, _ := delivery.EncodeBuilderBuild(delivery.BuilderBuild{State: delivery.BuildBuilding, By: "novox.builder", Manifest: manifestD,
			Step: "asked mesh-build-go", Asks: map[string]string{delivery.AskGo: id}})
		r.st.vals[r.key] = data
		r.b.Held = heldAsks{id: held}
		if held {
			r.asks.Answer = nil
			r.asks.End(delivery.Step{ID: id, Node: "shanks", State: delivery.StepPassed,
				Result: []byte(`{"artifacts":[{"artifact":"tool","digest":"` + digest + `","reference":"artifact-store://m/tool/blobs/` + digest + `"}]}`)})
		}
		v := r.consider(t, "modules/m")
		asks := r.asks.Asks()
		switch {
		case held && len(asks) != 0:
			t.Errorf("an ask the stream holds was put again: %+v", asks)
		case !held && (len(asks) != 1 || asks[0].ID != id):
			t.Errorf("the ask nobody put: asks %+v, want one under %s", asks, id)
		}
		if v.State != delivery.BuildDone {
			t.Errorf("held %v: the key = %+v, want done", held, v)
		}
	}
}

// unreadableHeld cannot tell whether an ask is held.
type unreadableHeld struct{}

func (unreadableHeld) Held(context.Context, delivery.StepAsk) (bool, error) {
	return false, errors.New("permissions violation for publish to $JS.API.STREAM.INFO.SEAT_NODE_BUILD_GO")
}

// 1910: a take-over that cannot read whether the ask its key names is on its stream says so and waits for the ask's step:
// the key is not failed, and the build finishes when a node ran the ask.
func TestATakeOverThatCannotReadTheStreamWaitsForTheAsk(t *testing.T) {
	r := newRig(t, goBundle)
	const id = "mvl0frv18d1959"
	data, _ := delivery.EncodeBuilderBuild(delivery.BuilderBuild{State: delivery.BuildBuilding, By: "novox.builder", Manifest: manifestD,
		Step: "asked mesh-build-go", Asks: map[string]string{delivery.AskGo: id}})
	r.st.vals[r.key] = data
	r.b.Held = unreadableHeld{}
	r.asks.Answer = nil
	r.asks.End(delivery.Step{ID: id, Node: "shanks", State: delivery.StepPassed,
		Result: []byte(`{"artifacts":[{"artifact":"tool","digest":"` + digest + `","reference":"artifact-store://m/tool/blobs/` + digest + `"}]}`)})
	v := r.consider(t, "modules/m")
	if v.State != delivery.BuildDone || len(r.asks.Asks()) != 0 {
		t.Fatalf("the key = %+v after %d asks, want done from the ask's step, none put", v, len(r.asks.Asks()))
	}
}