package proposals

import (
	"reflect"
	"testing"

	"gitea.maximumdirect.net/eric/audita/internal/core/schema"
)

func TestPreviewProposalForSegmentRequireUniqueSuccess(t *testing.T) {
	segment := &schema.Segment{ID: 7, Text: "The gestures are odd."}
	proposal := CorrectionProposal{
		TargetSegmentID: 7,
		OriginalText:    "gestures",
		CorrectedText:   "Jesters",
		Confidence:      0.9,
	}

	result := PreviewProposalForSegment(segment, proposal, ReplacementPolicyRequireUnique)
	if !result.Applicable {
		t.Fatalf("expected applicable preview, got skip reason %q", result.SkipReason)
	}
	if result.CorrectedSegmentText != "The Jesters are odd." {
		t.Fatalf("unexpected corrected text: %q", result.CorrectedSegmentText)
	}
	if result.ReplacementCount != 1 {
		t.Fatalf("expected 1 replacement, got %d", result.ReplacementCount)
	}
}

func TestPreviewProposalForSegmentRequireUniqueMissingOriginalText(t *testing.T) {
	segment := &schema.Segment{ID: 7, Text: "The jesters are odd."}
	proposal := CorrectionProposal{
		TargetSegmentID: 7,
		OriginalText:    "gestures",
		CorrectedText:   "Jesters",
		Confidence:      0.9,
	}

	result := PreviewProposalForSegment(segment, proposal, ReplacementPolicyRequireUnique)
	if result.Applicable {
		t.Fatal("expected non-applicable preview")
	}
	if result.SkipReason != SkipReasonMissingOriginalText {
		t.Fatalf("expected skip reason %q, got %q", SkipReasonMissingOriginalText, result.SkipReason)
	}
}

func TestPreviewProposalForSegmentRequireUniqueAmbiguousOriginalText(t *testing.T) {
	segment := &schema.Segment{ID: 7, Text: "rank and rank"}
	proposal := CorrectionProposal{
		TargetSegmentID: 7,
		OriginalText:    "rank",
		CorrectedText:   "Hrank",
		Confidence:      0.9,
	}

	result := PreviewProposalForSegment(segment, proposal, ReplacementPolicyRequireUnique)
	if result.Applicable {
		t.Fatal("expected non-applicable preview")
	}
	if result.SkipReason != SkipReasonAmbiguousOriginal {
		t.Fatalf("expected skip reason %q, got %q", SkipReasonAmbiguousOriginal, result.SkipReason)
	}
}

func TestPreviewProposalForSegmentReplaceAllSuccessMultipleOccurrences(t *testing.T) {
	segment := &schema.Segment{ID: 8, Text: "uh uh uh"}
	proposal := CorrectionProposal{
		TargetSegmentID: 8,
		OriginalText:    "uh",
		CorrectedText:   "um",
		Confidence:      0.9,
	}

	result := PreviewProposalForSegment(segment, proposal, ReplacementPolicyReplaceAll)
	if !result.Applicable {
		t.Fatalf("expected applicable preview, got skip reason %q", result.SkipReason)
	}
	if result.CorrectedSegmentText != "um um um" {
		t.Fatalf("unexpected corrected text: %q", result.CorrectedSegmentText)
	}
	if result.ReplacementCount != 3 {
		t.Fatalf("expected 3 replacements, got %d", result.ReplacementCount)
	}
}

func TestPreviewProposalForSegmentReplaceAllMissingOriginalText(t *testing.T) {
	segment := &schema.Segment{ID: 8, Text: "um um um"}
	proposal := CorrectionProposal{
		TargetSegmentID: 8,
		OriginalText:    "uh",
		CorrectedText:   "um",
		Confidence:      0.9,
	}

	result := PreviewProposalForSegment(segment, proposal, ReplacementPolicyReplaceAll)
	if result.Applicable {
		t.Fatal("expected non-applicable preview")
	}
	if result.SkipReason != SkipReasonMissingOriginalText {
		t.Fatalf("expected skip reason %q, got %q", SkipReasonMissingOriginalText, result.SkipReason)
	}
}

func TestPreviewProposalForSegmentNoEffectReplacement(t *testing.T) {
	segment := &schema.Segment{ID: 8, Text: "hello there"}
	proposal := CorrectionProposal{
		TargetSegmentID: 8,
		OriginalText:    "hello",
		CorrectedText:   "hello",
		Confidence:      0.9,
	}

	result := PreviewProposalForSegment(segment, proposal, ReplacementPolicyRequireUnique)
	if result.Applicable {
		t.Fatal("expected non-applicable preview")
	}
	if result.SkipReason != SkipReasonNoEffect {
		t.Fatalf("expected skip reason %q, got %q", SkipReasonNoEffect, result.SkipReason)
	}
}

func TestPreviewProposalForSegmentAllowsEmptyCorrectedTextWhenSegmentRemainsNonEmpty(t *testing.T) {
	segment := &schema.Segment{ID: 8, Text: "uh hello"}
	proposal := CorrectionProposal{
		TargetSegmentID: 8,
		OriginalText:    "uh ",
		CorrectedText:   "",
		Confidence:      0.9,
	}

	result := PreviewProposalForSegment(segment, proposal, ReplacementPolicyRequireUnique)
	if !result.Applicable {
		t.Fatalf("expected applicable preview, got skip reason %q", result.SkipReason)
	}
	if result.CorrectedSegmentText != "hello" {
		t.Fatalf("unexpected corrected text: %q", result.CorrectedSegmentText)
	}
}

func TestPreviewProposalForSegmentRejectsEmptyResultingSegment(t *testing.T) {
	segment := &schema.Segment{ID: 8, Text: "uh"}
	proposal := CorrectionProposal{
		TargetSegmentID: 8,
		OriginalText:    "uh",
		CorrectedText:   "",
		Confidence:      0.9,
	}

	result := PreviewProposalForSegment(segment, proposal, ReplacementPolicyRequireUnique)
	if result.Applicable {
		t.Fatal("expected non-applicable preview")
	}
	if result.SkipReason != SkipReasonEmptyResultingText {
		t.Fatalf("expected skip reason %q, got %q", SkipReasonEmptyResultingText, result.SkipReason)
	}
}

func TestPreviewProposalForSegmentPreservesInputSegment(t *testing.T) {
	segment := &schema.Segment{ID: 9, Speaker: "A", Start: 1.0, End: 2.0, Text: "rank rank"}
	original := *segment
	proposal := CorrectionProposal{
		TargetSegmentID: 9,
		OriginalText:    "rank",
		CorrectedText:   "Hrank",
		Confidence:      0.9,
	}

	_ = PreviewProposalForSegment(segment, proposal, ReplacementPolicyReplaceAll)

	if !reflect.DeepEqual(*segment, original) {
		t.Fatalf("segment mutated: before=%+v after=%+v", original, *segment)
	}
}

func TestPreviewProposalForSegmentLiteralMatchingCaseSensitiveAndPunctuation(t *testing.T) {
	segment := &schema.Segment{ID: 10, Text: "Hello, world."}

	punctuationProposal := CorrectionProposal{
		TargetSegmentID: 10,
		OriginalText:    "world.",
		CorrectedText:   "earth.",
		Confidence:      0.9,
	}
	punctuationResult := PreviewProposalForSegment(segment, punctuationProposal, ReplacementPolicyRequireUnique)
	if !punctuationResult.Applicable {
		t.Fatalf("expected punctuation proposal applicable, got skip reason %q", punctuationResult.SkipReason)
	}
	if punctuationResult.CorrectedSegmentText != "Hello, earth." {
		t.Fatalf("unexpected corrected text: %q", punctuationResult.CorrectedSegmentText)
	}

	caseMismatchProposal := CorrectionProposal{
		TargetSegmentID: 10,
		OriginalText:    "hello",
		CorrectedText:   "Hi",
		Confidence:      0.9,
	}
	caseMismatchResult := PreviewProposalForSegment(segment, caseMismatchProposal, ReplacementPolicyRequireUnique)
	if caseMismatchResult.Applicable {
		t.Fatal("expected case-mismatch proposal to be non-applicable")
	}
	if caseMismatchResult.SkipReason != SkipReasonMissingOriginalText {
		t.Fatalf("expected skip reason %q, got %q", SkipReasonMissingOriginalText, caseMismatchResult.SkipReason)
	}
}