package shape

import (
	"context"
	"reflect"
	"strings"
	"testing"
	"unicode/utf8"

	"gitea.maximumdirect.net/eric/notarius/internal/core/source"
	"gitea.maximumdirect.net/eric/notarius/internal/framework/contracts"
	"gitea.maximumdirect.net/eric/notarius/internal/framework/pipeline"
	"gitea.maximumdirect.net/eric/notarius/internal/modules/dnd"
)

func TestValidatorAcceptsEveryEventRuleAndNormalizableWhitespace(t *testing.T) {
	quantity := 1
	value := dnd.ItemEventList{Events: []dnd.ItemEvent{
		{Name: "  Hidden Cache  ", Kind: dnd.ItemEventKindDiscovered, From: " ", To: " ", SourceRefs: refs(1, 1)},
		{Name: "Gold Pieces", Kind: dnd.ItemEventKindAcquired, Quantity: &quantity, To: " party ", SourceRefs: refs(2, 2)},
		{Name: "Torch", Kind: dnd.ItemEventKindLost, From: " party ", SourceRefs: refs(3, 3)},
		{Name: "Potion", Kind: dnd.ItemEventKindConsumed, From: " Aria ", SourceRefs: refs(4, 4)},
		{Name: "Moonblade", Kind: dnd.ItemEventKindTransferred, From: "Aria", To: "Borin", SourceRefs: refs(5, 5)},
	}}
	result, err := New(Options{}).Validate(context.Background(), contracts.TypedValidationRequest[dnd.ItemEventList]{Value: value})
	if err != nil || !result.Approved {
		t.Fatalf("Validate() = %#v, %v", result, err)
	}
	empty, err := New(Options{}).Validate(context.Background(), contracts.TypedValidationRequest[dnd.ItemEventList]{Value: dnd.ItemEventList{Events: []dnd.ItemEvent{}}})
	if err != nil || !empty.Approved {
		t.Fatalf("empty list result = %#v, %v", empty, err)
	}
}

func TestValidatorRejectsOwnedSemanticBoundaries(t *testing.T) {
	valid := validList()
	zero := 0
	negative := -1
	tests := []struct {
		name  string
		value dnd.ItemEventList
		want  string
	}{
		{"missing events", dnd.ItemEventList{}, "events must be present"},
		{"blank name", listWith(dnd.ItemEvent{Name: " \t", Kind: dnd.ItemEventKindDiscovered, SourceRefs: refs(1, 1)}), "name must not be empty"},
		{"unsupported kind", listWith(dnd.ItemEvent{Name: "Ring", Kind: "unknown", SourceRefs: refs(1, 1)}), "kind is unsupported"},
		{"discovered holder", listWith(dnd.ItemEvent{Name: "Ring", Kind: dnd.ItemEventKindDiscovered, From: "Aria", SourceRefs: refs(1, 1)}), "incompatible"},
		{"acquired without holder", listWith(dnd.ItemEvent{Name: "Ring", Kind: dnd.ItemEventKindAcquired, SourceRefs: refs(1, 1)}), "incompatible"},
		{"lost destination", listWith(dnd.ItemEvent{Name: "Ring", Kind: dnd.ItemEventKindLost, From: "Aria", To: "Borin", SourceRefs: refs(1, 1)}), "incompatible"},
		{"consumed without holder", listWith(dnd.ItemEvent{Name: "Ring", Kind: dnd.ItemEventKindConsumed, SourceRefs: refs(1, 1)}), "incompatible"},
		{"party transfer from", listWith(dnd.ItemEvent{Name: "Ring", Kind: dnd.ItemEventKindTransferred, From: "party", To: "Borin", SourceRefs: refs(1, 1)}), "incompatible"},
		{"party transfer to", listWith(dnd.ItemEvent{Name: "Ring", Kind: dnd.ItemEventKindTransferred, From: "Aria", To: " PARTY ", SourceRefs: refs(1, 1)}), "incompatible"},
		{"case equivalent transfer", listWith(dnd.ItemEvent{Name: "Ring", Kind: dnd.ItemEventKindTransferred, From: "Aria", To: "aria", SourceRefs: refs(1, 1)}), "incompatible"},
		{"unicode equivalent transfer", listWith(dnd.ItemEvent{Name: "Ring", Kind: dnd.ItemEventKindTransferred, From: "Åria", To: "Åria", SourceRefs: refs(1, 1)}), "incompatible"},
		{"zero quantity", listWith(dnd.ItemEvent{Name: "Ring", Kind: dnd.ItemEventKindAcquired, Quantity: &zero, To: "party", SourceRefs: refs(1, 1)}), "quantity must be positive"},
		{"negative quantity", listWith(dnd.ItemEvent{Name: "Ring", Kind: dnd.ItemEventKindAcquired, Quantity: &negative, To: "party", SourceRefs: refs(1, 1)}), "quantity must be positive"},
		{"missing source refs", listWith(dnd.ItemEvent{Name: "Ring", Kind: dnd.ItemEventKindDiscovered}), "source_refs must contain"},
	}
	for _, test := range tests {
		t.Run(test.name, func(t *testing.T) {
			result, err := New(Options{}).Validate(context.Background(), contracts.TypedValidationRequest[dnd.ItemEventList]{Value: test.value})
			if err != nil || result.Approved || result.ReasonCode != ReasonCode || !strings.Contains(result.Message, test.want) {
				t.Fatalf("Validate() = %#v, %v; want %q", result, err, test.want)
			}
		})
	}
	if result, err := New(Options{}).Validate(context.Background(), contracts.TypedValidationRequest[dnd.ItemEventList]{Value: valid}); err != nil || !result.Approved {
		t.Fatalf("valid result = %#v, %v", result, err)
	}
}

func TestValidatorAggregatesBoundedIndexedDiagnosticsAndRegistration(t *testing.T) {
	value := dnd.ItemEventList{Events: make([]dnd.ItemEvent, 24)}
	for index := range value.Events {
		value.Events[index] = dnd.ItemEvent{Name: " \n", Kind: "unsupported"}
	}
	result, err := New(Options{}).Validate(context.Background(), contracts.TypedValidationRequest[dnd.ItemEventList]{Value: value})
	if err != nil || result.Approved || result.ReasonCode != ReasonCode || len([]byte(result.Message)) > 4096 || !utf8.ValidString(result.Message) || !strings.Contains(result.Message, "events[0]") || !strings.Contains(result.Message, "additional issue(s) omitted") {
		t.Fatalf("Validate() = %#v, %v", result, err)
	}
	if value.Events[0].Name != " \n" {
		t.Fatal("Validate() mutated input")
	}
	if got := New(Options{}).CheckpointFingerprints(); !reflect.DeepEqual(got, []pipeline.CheckpointFingerprint{{Name: "policy", Value: policy}}) {
		t.Fatalf("CheckpointFingerprints() = %#v", got)
	}
	registry := pipeline.NewValidatorRegistry()
	if err := Register(registry); err != nil {
		t.Fatal(err)
	}
	if got, ok := registry.Spec(Key); !ok || !reflect.DeepEqual(got, Spec()) {
		t.Fatalf("registry spec = %#v, %t", got, ok)
	}
	if _, err := DecodeOptions(map[string]any{"unexpected": true}); err == nil {
		t.Fatal("DecodeOptions() accepted unknown option")
	}
}

func validList() dnd.ItemEventList {
	return dnd.ItemEventList{Events: []dnd.ItemEvent{{Name: "Ring", Kind: dnd.ItemEventKindAcquired, To: "party", SourceRefs: refs(1, 1)}}}
}

func listWith(event dnd.ItemEvent) dnd.ItemEventList {
	return dnd.ItemEventList{Events: []dnd.ItemEvent{event}}
}

func refs(start, end int) []source.SourceRef {
	return []source.SourceRef{{SourceID: "session", StartUnitID: start, EndUnitID: end}}
}