package delivery

import (
	"encoding/json"
	"errors"
	"reflect"
	"strings"
	"testing"
)

func TestSourceKeys(t *testing.T) { // 1200/AC1
	if k, err := CandidatesKey("feat/delivery-source-keys"); err != nil || k != "feat/delivery-source-keys" {
		t.Fatalf("candidates key = %q, %v", k, err)
	}
	if g, err := ParseCandidatesKey("feat/x"); err != nil || g != "feat/x" {
		t.Fatalf("parse candidates = %q, %v", g, err)
	}
	if k, err := ModulesKey("mesh-mail"); err != nil || k != "mesh-mail" {
		t.Fatalf("modules key = %q, %v", k, err)
	}
	if m, err := ParseModulesKey("mesh-mail"); err != nil || m != "mesh-mail" {
		t.Fatalf("parse modules = %q, %v", m, err)
	}
	for _, bad := range []string{"", "a.b", "a*b", "a>b", "a b", "a\tb"} {
		if _, err := ModulesKey(bad); err == nil {
			t.Errorf("modules key %q accepted", bad)
		}
		if _, err := ParseCandidatesKey(bad); err == nil {
			t.Errorf("parse candidates %q accepted", bad)
		}
		if _, err := ParseModulesKey(bad); err == nil {
			t.Errorf("parse modules %q accepted", bad)
		}
	}
	if _, err := CandidatesKey(""); err == nil {
		t.Error("an empty candidates key accepted")
	}
	ev, err := ForgeEvent("novox/mesh-sdk", ForgeMerged)
	if err != nil || ev != "forge.novox.mesh-sdk.merged" {
		t.Fatalf("forge event = %q, %v", ev, err)
	}
	repo, kind, err := ParseForgeEvent(ev)
	if err != nil || repo != "novox/mesh-sdk" || kind != ForgeMerged {
		t.Fatalf("parse forge event = %q %q %v", repo, kind, err)
	}
	for _, k := range []string{ForgePull, ForgeMerged, ForgeRefused} {
		if _, err := ForgeEvent("a/b", k); err != nil {
			t.Errorf("kind %s refused: %v", k, err)
		}
	}
	for _, bad := range []struct{ repo, kind string }{
		{"", "pull"}, {"novox", "pull"}, {"a/b/c", "pull"}, {"/b", "pull"}, {"a/", "pull"},
		{"a.b/c", "pull"}, {"a/b c", "pull"}, {"a/b", "closed"}, {"a/b", ""},
	} {
		if _, err := ForgeEvent(bad.repo, bad.kind); err == nil {
			t.Errorf("forge event %q %q accepted", bad.repo, bad.kind)
		} else if bad.kind == "closed" && !strings.Contains(err.Error(), "closed") {
			t.Errorf("error does not name the kind: %v", err)
		}
	}
	for _, bad := range []string{"", "forge.a.b", "forge.a.b.closed", "x.a.b.pull", "forge.a.b.pull.x", "forge..b.pull"} {
		if _, _, err := ParseForgeEvent(bad); err == nil {
			t.Errorf("parse forge event %q accepted", bad)
		}
	}
}

func TestForgeOpenKind(t *testing.T) { // 1279/AC5
	ev := OpenEvent()
	if ev != "forge.open" {
		t.Fatalf("open event = %q", ev)
	}
	repo, kind, err := ParseForgeEvent(ev)
	if err != nil || repo != "" || kind != ForgeOpen {
		t.Fatalf("parse open event = %q %q %v", repo, kind, err)
	}
	// An empty list is a message too: nothing is open.
	data, err := EncodeForge(Forge{Kind: ForgeOpen, Open: []OpenPull{}})
	if err != nil {
		t.Fatalf("empty open: %v", err)
	}
	if f, err := DecodeForge(data); err != nil || f.Kind != ForgeOpen || len(f.Open) != 0 {
		t.Errorf("empty open round trip: %+v %v", f, err)
	}
	for name, f := range map[string]Forge{
		"a repository":  {Kind: ForgeOpen, Repository: "a/b", Open: []OpenPull{{Repository: "a/b", Number: 1}}},
		"a bad entry":   {Kind: ForgeOpen, Open: []OpenPull{{Repository: "a", Number: 1}}},
		"a zero number": {Kind: ForgeOpen, Open: []OpenPull{{Repository: "a/b"}}},
		"a head":        {Kind: ForgeOpen, Head: "x", Open: []OpenPull{{Repository: "a/b", Number: 1}}},
	} {
		if _, err := EncodeForge(f); err == nil {
			t.Errorf("open with %s accepted", name)
		}
	}
	if _, err := EncodeForge(Forge{Kind: ForgePull, Repository: "a/b", Number: 1, Head: "h", Action: "updated", Open: []OpenPull{{Repository: "a/b", Number: 1}}}); err == nil {
		t.Error("a pull message naming open pull requests accepted")
	}
	if _, err := ForgeEvent("a/b", ForgeOpen); err == nil {
		t.Error("an open event for a repository accepted")
	}
}

func TestHeadsHash(t *testing.T) { // 1200/AC2
	a := Head{Repository: "novox/mesh-sdk", Number: 36, Head: "aaaa"}
	b := Head{Repository: "novox/mesh-control", Number: 7, Head: "bbbb"}
	h1, err := HeadsHash([]Head{a, b})
	if err != nil {
		t.Fatal(err)
	}
	h2, _ := HeadsHash([]Head{b, a})
	if h1 != h2 {
		t.Errorf("order changes the hash: %s %s", h1, h2)
	}
	if len(h1) != 12 || strings.Trim(h1, "0123456789abcdef") != "" {
		t.Errorf("hash %q is not 12 hex digits", h1)
	}
	for _, changed := range []Head{
		{Repository: "novox/mesh-sdk", Number: 36, Head: "aaab"},
		{Repository: "novox/mesh-sdk", Number: 37, Head: "aaaa"},
		{Repository: "novox/other", Number: 36, Head: "aaaa"},
	} {
		h3, _ := HeadsHash([]Head{changed, b})
		if h3 == h1 {
			t.Errorf("changing %v keeps the hash", changed)
		}
	}
	if _, err := HeadsHash(nil); err == nil {
		t.Error("an empty list is accepted")
	}
}

func sampleSource() Source {
	return Source{Group: "feat/x", Heads: map[string]string{"novox/mesh-sdk": "abc123", "novox/mesh-control": "def456"}}
}

func sampleCandidate() Candidate {
	pulls := []CandidatePull{
		{Head: Head{Repository: "novox/mesh-sdk", Number: 36, Head: "aaaa"}, Modules: []string{"mesh-mail"}},
		{Head: Head{Repository: "novox/mesh-control", Number: 7, Head: "bbbb"}, Modules: []string{"mesh-controller"}},
	}
	hh, _ := HeadsHash([]Head{pulls[0].Head, pulls[1].Head})
	return Candidate{Group: "feat/x", Base: 12, HeadsHash: hh, Pulls: pulls}
}

func sampleForges() []Forge {
	return []Forge{
		{Kind: ForgePull, Repository: "novox/mesh-sdk", Branch: "feat/x", Number: 36, Head: "aaaa", Action: "opened"},
		{Kind: ForgeMerged, Repository: "novox/mesh-sdk", Number: 36, Head: "aaaa", Merge: "cccc",
			Trees: map[string]string{"modules/a": "t1"}, Root: "t0"},
		{Kind: ForgeRefused, Repository: "novox/mesh-sdk", Act: "novox/mesh-sdk.36.aaaa.view", Words: "403 forbidden"},
		{Kind: ForgeOpen, Open: []OpenPull{{Repository: "novox/mesh-sdk", Number: 36}, {Repository: "novox/mesh-control", Number: 7}}},
	}
}

func TestSourceValuesRoundTrip(t *testing.T) { // 1200/AC3
	check := func(name string, data []byte, err error) {
		t.Helper()
		if err != nil {
			t.Fatalf("%s: %v", name, err)
		}
		var probe map[string]any
		if err := json.Unmarshal(data, &probe); err != nil || probe["v"] != float64(1) {
			t.Fatalf("%s: json %s does not carry v:1", name, data)
		}
	}
	s := sampleSource()
	data, err := EncodeSource(s)
	check("source", data, err)
	s.V = Version
	if got, err := DecodeSource(data); err != nil || !SameSource(got, s) {
		t.Errorf("source round trip: %+v %v", got, err)
	}
	c := sampleCandidate()
	data, err = EncodeCandidate(c)
	check("candidate", data, err)
	c.V = Version
	if got, err := DecodeCandidate(data); err != nil || !SameCandidate(got, c) {
		t.Errorf("candidate round trip: %+v %v", got, err)
	}
	for _, m := range []Module{
		{FP: "src1:abc", Src: 5, Repository: "novox/mesh-sdk", Commit: "cccc"},
		{None: "a build that resolves packages when built", Repository: "novox/mesh-sdk", Commit: "cccc"},
	} {
		data, err = EncodeModule(m)
		check("module", data, err)
		m.V = Version
		if got, err := DecodeModule(data); err != nil || !SameModule(got, m) {
			t.Errorf("module round trip: %+v %v", got, err)
		}
	}
	for _, f := range sampleForges() {
		data, err = EncodeForge(f)
		check("forge "+f.Kind, data, err)
		f.V = Version
		if got, err := DecodeForge(data); err != nil || !SameForge(got, f) {
			t.Errorf("forge %s round trip: %+v %v", f.Kind, got, err)
		}
	}
	for name, dec := range map[string]func([]byte) error{
		"source":    func(b []byte) error { _, err := DecodeSource(b); return err },
		"candidate": func(b []byte) error { _, err := DecodeCandidate(b); return err },
		"module":    func(b []byte) error { _, err := DecodeModule(b); return err },
		"forge":     func(b []byte) error { _, err := DecodeForge(b); return err },
	} {
		for _, in := range []string{`{"group":"g"}`, `{"v":2,"group":"g"}`} {
			if err := dec([]byte(in)); !errors.Is(err, ErrUnknownVersion) {
				t.Errorf("%s decode of %s = %v, want ErrUnknownVersion", name, in, err)
			}
		}
	}
}

func TestSourceValuesRefused(t *testing.T) { // 1200/AC4
	wantErr := func(name string, err error, words ...string) {
		t.Helper()
		if err == nil {
			t.Errorf("%s accepted", name)
			return
		}
		for _, w := range words {
			if !strings.Contains(err.Error(), w) {
				t.Errorf("%s: error %q does not name %q", name, err, w)
			}
		}
	}
	_, err := EncodeSource(Source{Group: "g"})
	wantErr("source without repositories", err, "repositor")
	_, err = EncodeSource(Source{Group: "g", Heads: map[string]string{"a/b": ""}})
	wantErr("source with an empty head", err, "a/b")
	_, err = EncodeSource(Source{Group: "g", Heads: map[string]string{"": "x"}})
	wantErr("source with an empty repository", err, "repositor")

	c := sampleCandidate()
	c.HeadsHash = "000000000000"
	_, err = EncodeCandidate(c)
	wantErr("candidate with a stale hash", err, "heads hash")
	c = sampleCandidate()
	c.Pulls = nil
	_, err = EncodeCandidate(c)
	wantErr("candidate without pulls", err, "pull")

	_, err = EncodeModule(Module{FP: "src1:x", None: "why", Repository: "a/b", Commit: "c"})
	wantErr("module with both", err, "both")
	_, err = EncodeModule(Module{Repository: "a/b", Commit: "c"})
	wantErr("module with neither", err, "fingerprint", "none")
	_, err = EncodeModule(Module{FP: "abc", Repository: "a/b", Commit: "c"})
	wantErr("module with a bad fingerprint", err, "src1:")

	f := sampleForges()[1]
	f.Merge = ""
	_, err = EncodeForge(f)
	wantErr("merged without merge commit", err, "merge")
	f = sampleForges()[1]
	f.Root = ""
	_, err = EncodeForge(f)
	wantErr("merged without root", err, "root")
	f = sampleForges()[1]
	f.Trees = nil
	_, err = EncodeForge(f)
	wantErr("merged without trees", err, "tree")
	f = sampleForges()[1]
	f.Trees = map[string]string{"modules/a": ""}
	_, err = EncodeForge(f)
	wantErr("merged with an empty tree", err, "modules/a")
	f = sampleForges()[0]
	f.Action = "reopened"
	_, err = EncodeForge(f)
	wantErr("pull with an unknown action", err, "reopened")
	f = sampleForges()[0]
	f.Head = ""
	_, err = EncodeForge(f)
	wantErr("pull without head", err, "head")
	f = sampleForges()[2]
	f.Words = ""
	_, err = EncodeForge(f)
	wantErr("refused without words", err, "words")
	f = sampleForges()[2]
	f.Act = ""
	_, err = EncodeForge(f)
	wantErr("refused without act", err, "act")
	_, err = EncodeForge(Forge{Kind: "closed", Repository: "a/b"})
	wantErr("unknown kind", err, "closed")
	_, err = EncodeForge(Forge{Kind: ForgePull, Repository: "nope", Number: 1, Head: "h", Action: "opened"})
	wantErr("bad repository", err, "nope")
}

func TestSourceSame(t *testing.T) { // 1200/AC5
	if !SameSource(sampleSource(), sampleSource()) {
		t.Error("equal sources differ")
	}
	s := sampleSource()
	s.Heads["novox/mesh-sdk"] = "zzz"
	if SameSource(s, sampleSource()) {
		t.Error("different sources are the same")
	}
	if !SameCandidate(sampleCandidate(), sampleCandidate()) {
		t.Error("equal candidates differ")
	}
	c := sampleCandidate()
	c.Pulls[0].Modules = []string{"other"}
	if SameCandidate(c, sampleCandidate()) {
		t.Error("different candidates are the same")
	}
	m := Module{FP: "src1:a", Repository: "a/b", Commit: "c"}
	if !SameModule(m, m) || SameModule(m, Module{FP: "src1:b", Repository: "a/b", Commit: "c"}) {
		t.Error("SameModule wrong")
	}
	f := sampleForges()[1]
	g := sampleForges()[1]
	if !SameForge(f, g) {
		t.Error("equal forge messages differ")
	}
	g.Trees["modules/a"] = "other"
	if SameForge(f, g) {
		t.Error("different forge messages are the same")
	}
}

func TestSourceBuckets(t *testing.T) {
	if SourceBucket != "mesh-delivery-gate_source" || CandidatesBucket != "mesh-delivery-indexer_candidates" ||
		ModulesBucket != "mesh-delivery-indexer_modules" || SourceMainKey != "main" ||
		SourceHistory != 64 || CandidatesHistory != 10 || ModulesHistory != 20 {
		t.Error("a bucket or history differs from the decided layout")
	}
}

func TestForgeDirs(t *testing.T) {
	pull := func(dirs []string, known bool) Forge {
		return Forge{Kind: ForgePull, Repository: "novox/mesh-sdk", Number: 36, Head: "aaaa", Action: "updated", Dirs: dirs, DirsKnown: known}
	}
	round := func(f Forge) Forge {
		t.Helper()
		data, err := EncodeForge(f)
		if err != nil {
			t.Fatal(err)
		}
		got, err := DecodeForge(data)
		if err != nil {
			t.Fatal(err)
		}
		return got
	}
	// 1233/AC2: the directories come back equal and in order.
	got := round(pull([]string{"modules/a", "modules/b"}, true))
	if !reflect.DeepEqual(got.Dirs, []string{"modules/a", "modules/b"}) || !got.DirsKnown {
		t.Errorf("dirs = %v known %v", got.Dirs, got.DirsKnown)
	}
	// 1233/AC3: a head changing no module directory is told apart from one whose directories could not be said.
	none, unknown := round(pull(nil, true)), round(pull(nil, false))
	if !none.DirsKnown || len(none.Dirs) != 0 {
		t.Errorf("known and empty: dirs %v known %v", none.Dirs, none.DirsKnown)
	}
	if unknown.DirsKnown || len(unknown.Dirs) != 0 {
		t.Errorf("not known: dirs %v known %v", unknown.Dirs, unknown.DirsKnown)
	}
	// 1233/AC4: a merged or a refused message carrying directories is refused.
	m := sampleForges()[1]
	m.Dirs, m.DirsKnown = []string{"modules/a"}, true
	if _, err := EncodeForge(m); err == nil {
		t.Error("merged message with dirs accepted")
	}
	r := sampleForges()[2]
	r.Dirs, r.DirsKnown = []string{"modules/a"}, true
	if _, err := EncodeForge(r); err == nil {
		t.Error("refused message with dirs accepted")
	}
	r = sampleForges()[2]
	r.DirsKnown = true
	if _, err := EncodeForge(r); err == nil {
		t.Error("refused message with dirs-known accepted")
	}
	// directories on a pull message that does not say it knows them are refused too.
	if _, err := EncodeForge(pull([]string{"modules/a"}, false)); err == nil {
		t.Error("dirs without dirs-known accepted")
	}
}