package dnd

import (
	"encoding/json"
	"strings"
	"testing"

	"gitea.maximumdirect.net/eric/notarius/internal/core/source"
)

func TestUnitRefUnmarshalAcceptsIntegerAndString(t *testing.T) {
	var integerRef UnitRef
	if err := json.Unmarshal([]byte(`12`), &integerRef); err != nil {
		t.Fatalf("Unmarshal(integer) error = %v, want nil", err)
	}
	if got := integerRef.String(); got != "12" {
		t.Fatalf("integer ref = %q, want 12", got)
	}

	var stringRef UnitRef
	if err := json.Unmarshal([]byte(`"seg-001"`), &stringRef); err != nil {
		t.Fatalf("Unmarshal(string) error = %v, want nil", err)
	}
	if got := stringRef.String(); got != "seg-001" {
		t.Fatalf("string ref = %q, want seg-001", got)
	}
}

func TestUnitRefUnmarshalRejectsNonIntegerTypes(t *testing.T) {
	for _, raw := range []string{`true`, `null`, `1.5`, `{}`} {
		t.Run(raw, func(t *testing.T) {
			var ref UnitRef
			err := json.Unmarshal([]byte(raw), &ref)
			if err == nil {
				t.Fatal("Unmarshal() error = nil, want error")
			}
			if !strings.Contains(err.Error(), "string or integer") {
				t.Fatalf("Unmarshal() error = %q, want type context", err.Error())
			}
		})
	}
}

func TestResolveUnitIDPrefersExactSourceUnitID(t *testing.T) {
	doc := unitRefSourceDocument("2", "10")

	got, err := ResolveUnitID(doc, "start_unit_id", UnitRefFromInt(2))
	if err != nil {
		t.Fatalf("ResolveUnitID() error = %v, want nil", err)
	}
	if got != "2" {
		t.Fatalf("ResolveUnitID() = %q, want exact source unit ID", got)
	}
}

func TestResolveUnitIDFallsBackToOneBasedUnitNumber(t *testing.T) {
	doc := unitRefSourceDocument("seg-001", "seg-002")

	got, err := ResolveUnitID(doc, "end_unit_id", UnitRefFromInt(2))
	if err != nil {
		t.Fatalf("ResolveUnitID() error = %v, want nil", err)
	}
	if got != "seg-002" {
		t.Fatalf("ResolveUnitID() = %q, want second source unit ID", got)
	}
}

func TestResolveUnitIDRejectsMissingUnit(t *testing.T) {
	doc := unitRefSourceDocument("seg-001")

	_, err := ResolveUnitID(doc, "start_unit_id", UnitRefFromInt(9))
	if err == nil {
		t.Fatal("ResolveUnitID() error = nil, want error")
	}
	if !strings.Contains(err.Error(), "start_unit_id 9") {
		t.Fatalf("ResolveUnitID() error = %q, want field and value context", err.Error())
	}
}

func TestSourceRefCandidateCanonicalizesValidRefsAndPreservesInvalidRefs(t *testing.T) {
	doc := unitRefSourceDocument("seg-001", "seg-002")

	valid := SourceRefCandidate(doc, SourceRefResponse{
		SourceID:    " session-alpha ",
		StartUnitID: UnitRefFromInt(1),
		EndUnitID:   UnitRefFromInt(2),
	})
	if valid != (source.SourceRef{SourceID: "session-alpha", StartUnitID: "seg-001", EndUnitID: "seg-002"}) {
		t.Fatalf("valid candidate = %#v, want canonical source ref", valid)
	}

	invalid := SourceRefCandidate(doc, SourceRefResponse{
		SourceID:    "session-alpha",
		StartUnitID: UnitRefFromInt(9),
		EndUnitID:   UnitRefFromString("missing"),
	})
	if invalid != (source.SourceRef{SourceID: "session-alpha", StartUnitID: "9", EndUnitID: "missing"}) {
		t.Fatalf("invalid candidate = %#v, want unresolved values for validator", invalid)
	}
}

func unitRefSourceDocument(ids ...string) *source.SourceDocument {
	doc := &source.SourceDocument{
		ID:     "session-alpha",
		Kind:   "transcript",
		Format: "application/json",
		Digest: "sha256:test",
	}
	for _, id := range ids {
		doc.Units = append(doc.Units, source.SourceUnit{
			ID:   id,
			Kind: "transcript_segment",
			Text: "text",
		})
	}
	return doc
}