package intent

import (
	"context"
	"testing"
)

// buildCommandSnap 组装命令测试用快照：一个带必填槽位的意图与一个无槽位意图。
func buildCommandSnap(t *testing.T) *Snapshot {
	t.Helper()
	b := NewRegistryBuilder(Options{})
	if err := b.Register(IntentSpec{
		ID: "report.generate", Domain: "report", Version: 1,
		Matcher: MatchSpec{IncludesAny: []string{"生成报告"}},
		Slots: []SlotSpec{
			{Key: "topic", Required: true, Pattern: `主题是(.+)`, Question: "要查询哪个主题？"},
		},
		Handler: "reportHandler",
	}); err != nil {
		t.Fatal(err)
	}
	if err := b.Register(IntentSpec{
		ID: "report.chat", Domain: "report", Version: 1,
		Matcher: MatchSpec{IncludesAny: []string{"闲聊一下"}},
	}); err != nil {
		t.Fatal(err)
	}
	reg, err := b.Build()
	if err != nil {
		t.Fatal(err)
	}
	return reg.Snapshot()
}

func recognize(t *testing.T, snap *Snapshot, input string) Result {
	t.Helper()
	res, err := NewRecognizer(Options{}, nil, nil).Recognize(context.Background(), input, snap)
	if err != nil {
		t.Fatal(err)
	}
	return res
}

// TestCommandsMatchedFullSlots：槽位齐全 → 单条 Start，ActionRef 取 Handler。
func TestCommandsMatchedFullSlots(t *testing.T) {
	snap := buildCommandSnap(t)
	res := recognize(t, snap, "帮我生成报告，主题是电机")
	if res.Branch != BranchMatched {
		t.Fatalf("branch = %s", res.Branch)
	}
	if len(res.Commands) != 1 {
		t.Fatalf("commands = %+v", res.Commands)
	}
	cmd := res.Commands[0]
	if cmd.Kind != CommandStart || cmd.Action.Kind != ActionHandler || cmd.Action.ID != "reportHandler" {
		t.Fatalf("start = %+v", cmd)
	}
	if cmd.Slots["topic"] != "电机" {
		t.Fatalf("slots = %v", cmd.Slots)
	}
}

// TestCommandsMatchedMissingSlot：必填缺失 → Start（带已抽槽）+ Clarify（含建议提问）。
func TestCommandsMatchedMissingSlot(t *testing.T) {
	snap := buildCommandSnap(t)
	res := recognize(t, snap, "帮我生成报告")
	if len(res.Commands) != 2 {
		t.Fatalf("commands = %+v", res.Commands)
	}
	start, clarify := res.Commands[0], res.Commands[1]
	if start.Kind != CommandStart {
		t.Fatalf("first = %+v", start)
	}
	if clarify.Kind != CommandClarify || len(clarify.Missing) != 1 || clarify.Missing[0] != "topic" {
		t.Fatalf("clarify = %+v", clarify)
	}
	if clarify.Question != "要查询哪个主题？" {
		t.Fatalf("question = %q", clarify.Question)
	}
}

// TestCommandsExpectationSetSlotPlusStart：预期命中 → SetSlot + Start（验收形态）。
func TestCommandsExpectationSetSlotPlusStart(t *testing.T) {
	snap := buildCommandSnap(t)
	exp := listExpectation{ids: []string{"report.generate"}}
	res, err := NewRecognizer(Options{}, exp, nil).Recognize(context.Background(), "生成报告，主题是电机", snap)
	if err != nil {
		t.Fatal(err)
	}
	if res.Branch != BranchExpectationHit {
		t.Fatalf("branch = %s", res.Branch)
	}
	var setSlot, start *Command
	for i := range res.Commands {
		switch res.Commands[i].Kind {
		case CommandSetSlot:
			setSlot = &res.Commands[i]
		case CommandStart:
			start = &res.Commands[i]
		}
	}
	if setSlot == nil || start == nil {
		t.Fatalf("commands = %+v", res.Commands)
	}
	if setSlot.Name != "topic" || setSlot.Value != "电机" {
		t.Fatalf("set_slot = %+v", *setSlot)
	}
	if start.Action.Kind != ActionHandler || start.Slots["topic"] != "电机" {
		t.Fatalf("start = %+v", *start)
	}
}

// TestCommandsAmbiguousClarify：标歧 → 单条 Clarify 携带候选 ID。
func TestCommandsAmbiguousClarify(t *testing.T) {
	b := NewRegistryBuilder(Options{})
	if err := b.Register(IntentSpec{ID: "demo.alpha", Domain: "demo", Version: 1, Matcher: MatchSpec{IncludesAny: []string{"模糊词"}}}); err != nil {
		t.Fatal(err)
	}
	if err := b.Register(IntentSpec{ID: "demo.beta", Domain: "demo", Version: 1, Matcher: MatchSpec{IncludesAny: []string{"模糊词"}}}); err != nil {
		t.Fatal(err)
	}
	reg, err := b.Build()
	if err != nil {
		t.Fatal(err)
	}
	res := recognize(t, reg.Snapshot(), "模糊词")
	if res.Branch != BranchAmbiguous {
		t.Fatalf("branch = %s", res.Branch)
	}
	if len(res.Commands) != 1 || res.Commands[0].Kind != CommandClarify {
		t.Fatalf("commands = %+v", res.Commands)
	}
	if len(res.Commands[0].Candidates) != 2 {
		t.Fatalf("candidates = %v", res.Commands[0].Candidates)
	}
}

// TestCommandsFallbackEmpty：fallback 不产出命令。
func TestCommandsFallbackEmpty(t *testing.T) {
	snap := buildCommandSnap(t)
	res := recognize(t, snap, "完全不相关的一句话")
	if res.Branch != BranchFallback || len(res.Commands) != 0 {
		t.Fatalf("fallback commands = %+v", res.Commands)
	}
}

// TestActionRefDerivation：blueprint 键优先于 Handler；都没有回落 auto。
func TestActionRefDerivation(t *testing.T) {
	if got := actionOf(Candidate{ID: "x", Metadata: map[string]string{"blueprint": "bp-1"}, Handler: "h"}); got.Kind != ActionBlueprint || got.ID != "bp-1" {
		t.Fatalf("blueprint = %+v", got)
	}
	if got := actionOf(Candidate{ID: "x", Handler: "h"}); got.Kind != ActionHandler || got.ID != "h" {
		t.Fatalf("handler = %+v", got)
	}
	if got := actionOf(Candidate{ID: "x"}); got.Kind != ActionAuto || got.ID != "x" {
		t.Fatalf("auto = %+v", got)
	}
}

type listExpectation struct{ ids []string }

func (s listExpectation) Pending(ctx context.Context) *PendingExpectation {
	return &PendingExpectation{IntentIDs: s.ids}
}

// TestSpecActionDeclaredWins：spec.action 显式声明在 ActionRef 推导中胜出（WP2）。
func TestSpecActionDeclaredWins(t *testing.T) {
	b := NewRegistryBuilder(Options{})
	if err := b.Register(IntentSpec{
		ID: "report.explicit", Domain: "report", Version: 1,
		Matcher: MatchSpec{IncludesAny: []string{"显式动作"}},
		Action:  &ActionRef{Kind: ActionWorkflow, ID: "wf-report"},
	}); err != nil {
		t.Fatal(err)
	}
	reg, err := b.Build()
	if err != nil {
		t.Fatal(err)
	}
	res := recognize(t, reg.Snapshot(), "显式动作")
	if len(res.Commands) != 1 || res.Commands[0].Kind != CommandStart {
		t.Fatalf("commands = %+v", res.Commands)
	}
	if got := res.Commands[0].Action; got.Kind != ActionWorkflow || got.ID != "wf-report" {
		t.Fatalf("action = %+v", got)
	}
}

// TestSpecActionValidation：action.kind 非法与 id 为空都被拒绝。
func TestSpecActionValidation(t *testing.T) {
	bad := IntentSpec{
		ID: "report.bad", Domain: "report", Version: 1,
		Matcher: MatchSpec{IncludesAny: []string{"x"}},
		Action:  &ActionRef{Kind: "bogus", ID: "y"},
	}
	b := NewRegistryBuilder(Options{})
	if err := b.Register(bad); err == nil {
		t.Fatal("bogus action kind accepted")
	}
	bad.Action = &ActionRef{Kind: ActionCommand, ID: ""}
	b2 := NewRegistryBuilder(Options{})
	if err := b2.Register(bad); err == nil {
		t.Fatal("empty action id accepted")
	}
}