package sync

import (
	"testing"

	"sub-cli/internal/model"
)

func TestSyncVTTTimeline(t *testing.T) {
	testCases := []struct {
		name   string
		source model.Subtitle
		target model.Subtitle
		verify func(t *testing.T, result model.Subtitle)
	}{
		{
			name: "Equal entry counts",
			source: model.Subtitle{
				Format: "vtt",
				Title:  "Source VTT",
				Entries: []model.SubtitleEntry{
					{
						Index:     1,
						StartTime: model.Timestamp{Seconds: 1},
						EndTime:   model.Timestamp{Seconds: 4},
						Text:      "Source line one.",
					},
					{
						Index:     2,
						StartTime: model.Timestamp{Seconds: 5},
						EndTime:   model.Timestamp{Seconds: 8},
						Text:      "Source line two.",
					},
					{
						Index:     3,
						StartTime: model.Timestamp{Seconds: 9},
						EndTime:   model.Timestamp{Seconds: 12},
						Text:      "Source line three.",
					},
				},
			},
			target: model.Subtitle{
				Format: "vtt",
				Title:  "Target VTT",
				Styles: map[string]string{
					"style1": ".style1 { color: red; }",
				},
				Entries: []model.SubtitleEntry{
					{
						Index:     1,
						StartTime: model.Timestamp{Minutes: 1, Seconds: 0},
						EndTime:   model.Timestamp{Minutes: 1, Seconds: 3},
						Text:      "Target line one.",
						Styles: map[string]string{
							"align":    "start",
							"position": "10%",
						},
					},
					{
						Index:     2,
						StartTime: model.Timestamp{Minutes: 1, Seconds: 5},
						EndTime:   model.Timestamp{Minutes: 1, Seconds: 8},
						Text:      "Target line two.",
						Styles: map[string]string{
							"align": "middle",
						},
					},
					{
						Index:     3,
						StartTime: model.Timestamp{Minutes: 1, Seconds: 10},
						EndTime:   model.Timestamp{Minutes: 1, Seconds: 13},
						Text:      "Target line three.",
					},
				},
			},
			verify: func(t *testing.T, result model.Subtitle) {
				if len(result.Entries) != 3 {
					t.Errorf("Expected 3 entries, got %d", len(result.Entries))
					return
				}
				
				// Check that source timings are applied to target entries
				if result.Entries[0].StartTime.Seconds != 1 || result.Entries[0].EndTime.Seconds != 4 {
					t.Errorf("First entry timing mismatch: got %+v", result.Entries[0])
				}
				
				if result.Entries[1].StartTime.Seconds != 5 || result.Entries[1].EndTime.Seconds != 8 {
					t.Errorf("Second entry timing mismatch: got %+v", result.Entries[1])
				}
				
				if result.Entries[2].StartTime.Seconds != 9 || result.Entries[2].EndTime.Seconds != 12 {
					t.Errorf("Third entry timing mismatch: got %+v", result.Entries[2])
				}
				
				// Check that target content is preserved
				if result.Entries[0].Text != "Target line one." {
					t.Errorf("Content should be preserved, got: %s", result.Entries[0].Text)
				}
				
				// Check that styles are preserved
				if result.Entries[0].Styles["align"] != "start" || result.Entries[0].Styles["position"] != "10%" {
					t.Errorf("Styles should be preserved, got: %+v", result.Entries[0].Styles)
				}
				
				// Check that global styles are preserved
				if result.Styles["style1"] != ".style1 { color: red; }" {
					t.Errorf("Global styles should be preserved, got: %+v", result.Styles)
				}
				
				// Check that numbering is correct
				if result.Entries[0].Index != 1 || result.Entries[1].Index != 2 || result.Entries[2].Index != 3 {
					t.Errorf("Entry indices should be sequential: %+v", result.Entries)
				}
			},
		},
		{
			name: "More target entries than source",
			source: model.Subtitle{
				Format: "vtt",
				Entries: []model.SubtitleEntry{
					{
						Index:     1,
						StartTime: model.Timestamp{Seconds: 1},
						EndTime:   model.Timestamp{Seconds: 4},
						Text:      "Source line one.",
					},
					{
						Index:     2,
						StartTime: model.Timestamp{Seconds: 5},
						EndTime:   model.Timestamp{Seconds: 8},
						Text:      "Source line two.",
					},
				},
			},
			target: model.Subtitle{
				Format: "vtt",
				Title:  "Target VTT",
				Entries: []model.SubtitleEntry{
					{
						Index:     1,
						StartTime: model.Timestamp{Minutes: 1, Seconds: 0},
						EndTime:   model.Timestamp{Minutes: 1, Seconds: 3},
						Text:      "Target line one.",
					},
					{
						Index:     2,
						StartTime: model.Timestamp{Minutes: 1, Seconds: 5},
						EndTime:   model.Timestamp{Minutes: 1, Seconds: 8},
						Text:      "Target line two.",
					},
					{
						Index:     3,
						StartTime: model.Timestamp{Minutes: 1, Seconds: 10},
						EndTime:   model.Timestamp{Minutes: 1, Seconds: 13},
						Text:      "Target line three.",
					},
				},
			},
			verify: func(t *testing.T, result model.Subtitle) {
				if len(result.Entries) != 3 {
					t.Errorf("Expected 3 entries, got %d", len(result.Entries))
					return
				}
				
				// First entry should use first source timing
				if result.Entries[0].StartTime.Seconds != 1 {
					t.Errorf("First entry should have first source timing, got: %+v", result.Entries[0].StartTime)
				}
				
				// Last entry should use last source timing
				if result.Entries[2].StartTime.Seconds != 5 {
					t.Errorf("Last entry should have last source timing, got: %+v", result.Entries[2].StartTime)
				}
				
				// Check that target content is preserved
				if result.Entries[2].Text != "Target line three." {
					t.Errorf("Content should be preserved, got: %s", result.Entries[2].Text)
				}
				
				// Check that title is preserved
				if result.Title != "Target VTT" {
					t.Errorf("Title should be preserved, got: %s", result.Title)
				}
			},
		},
		{
			name: "More source entries than target",
			source: model.Subtitle{
				Format: "vtt",
				Entries: []model.SubtitleEntry{
					{
						Index:     1,
						StartTime: model.Timestamp{Seconds: 1},
						EndTime:   model.Timestamp{Seconds: 3},
						Text:      "Source line one.",
					},
					{
						Index:     2,
						StartTime: model.Timestamp{Seconds: 4},
						EndTime:   model.Timestamp{Seconds: 6},
						Text:      "Source line two.",
					},
					{
						Index:     3,
						StartTime: model.Timestamp{Seconds: 7},
						EndTime:   model.Timestamp{Seconds: 9},
						Text:      "Source line three.",
					},
					{
						Index:     4,
						StartTime: model.Timestamp{Seconds: 10},
						EndTime:   model.Timestamp{Seconds: 12},
						Text:      "Source line four.",
					},
				},
			},
			target: model.Subtitle{
				Format: "vtt",
				Metadata: map[string]string{
					"Region": "metadata region",
				},
				Entries: []model.SubtitleEntry{
					{
						Index:     1,
						StartTime: model.Timestamp{Minutes: 1, Seconds: 0},
						EndTime:   model.Timestamp{Minutes: 1, Seconds: 3},
						Text:      "Target line one.",
					},
					{
						Index:     2,
						StartTime: model.Timestamp{Minutes: 1, Seconds: 5},
						EndTime:   model.Timestamp{Minutes: 1, Seconds: 8},
						Text:      "Target line two.",
					},
				},
			},
			verify: func(t *testing.T, result model.Subtitle) {
				if len(result.Entries) != 2 {
					t.Errorf("Expected 2 entries, got %d", len(result.Entries))
					return
				}
				
				// First entry should have first source timing
				if result.Entries[0].StartTime.Seconds != 1 {
					t.Errorf("First entry should have first source timing, got: %+v", result.Entries[0].StartTime)
				}
				
				// Last entry should have last source timing
				if result.Entries[1].StartTime.Seconds != 10 {
					t.Errorf("Last entry should have last source timing, got: %+v", result.Entries[1].StartTime)
				}
				
				// Check that metadata is preserved
				if result.Metadata["Region"] != "metadata region" {
					t.Errorf("Metadata should be preserved, got: %+v", result.Metadata)
				}
				
				// Check that target content is preserved
				if result.Entries[0].Text != "Target line one." || result.Entries[1].Text != "Target line two." {
					t.Errorf("Content should be preserved, got: %+v", result.Entries)
				}
			},
		},
		{
			name: "Empty target entries",
			source: model.Subtitle{
				Format: "vtt",
				Entries: []model.SubtitleEntry{
					{
						Index:     1,
						StartTime: model.Timestamp{Seconds: 1},
						EndTime:   model.Timestamp{Seconds: 4},
						Text:      "Source line one.",
					},
				},
			},
			target: model.Subtitle{
				Format: "vtt",
				Title:  "Empty Target",
			},
			verify: func(t *testing.T, result model.Subtitle) {
				if len(result.Entries) != 0 {
					t.Errorf("Expected 0 entries, got %d", len(result.Entries))
				}
				
				// Title should be preserved
				if result.Title != "Empty Target" {
					t.Errorf("Title should be preserved, got: %s", result.Title)
				}
			},
		},
		{
			name: "Empty source entries",
			source: model.Subtitle{
				Format: "vtt",
			},
			target: model.Subtitle{
				Format: "vtt",
				Title:  "Target with content",
				Entries: []model.SubtitleEntry{
					{
						Index:     1,
						StartTime: model.Timestamp{Seconds: 10},
						EndTime:   model.Timestamp{Seconds: 15},
						Text:      "Target line one.",
					},
				},
			},
			verify: func(t *testing.T, result model.Subtitle) {
				if len(result.Entries) != 1 {
					t.Errorf("Expected 1 entry, got %d", len(result.Entries))
					return
				}
				
				// Timing should be preserved since source is empty
				if result.Entries[0].StartTime.Seconds != 10 || result.Entries[0].EndTime.Seconds != 15 {
					t.Errorf("Timing should match target when source is empty, got: %+v", result.Entries[0])
				}
				
				// Content should be preserved
				if result.Entries[0].Text != "Target line one." {
					t.Errorf("Content should be preserved, got: %s", result.Entries[0].Text)
				}
				
				// Title should be preserved
				if result.Title != "Target with content" {
					t.Errorf("Title should be preserved, got: %s", result.Title)
				}
			},
		},
	}
	
	for _, tc := range testCases {
		t.Run(tc.name, func(t *testing.T) {
			result := syncVTTTimeline(tc.source, tc.target)
			
			if tc.verify != nil {
				tc.verify(t, result)
			}
		})
	}
}