package terrace

import (
	"testing"
)

func TestParseLine(t *testing.T) {
	tests := []struct {
		name          string
		line          string
		lineData      *LineData
		expected      *LineData
		expectError   bool
	}{
		{
			name:     "empty line",
			line:     "",
			lineData: NewLineData(' '),
			expected: &LineData{Indent: ' ', Level: 0, OffsetHead: 0, OffsetTail: 0},
		},
		{
			name:     "no indentation",
			line:     "hello world",
			lineData: NewLineData(' '),
			expected: &LineData{Indent: ' ', Level: 0, OffsetHead: 0, OffsetTail: 5},
		},
		{
			name:     "with indentation",
			line:     "  hello world",
			lineData: NewLineData(' '),
			expected: &LineData{Indent: ' ', Level: 2, OffsetHead: 2, OffsetTail: 7},
		},
		{
			name:     "only head",
			line:     "hello",
			lineData: NewLineData(' '),
			expected: &LineData{Indent: ' ', Level: 0, OffsetHead: 0, OffsetTail: 5},
		},
		{
			name:        "nil lineData",
			line:        "hello",
			lineData:    nil,
			expectError: true,
		},
		{
			name:        "invalid indent",
			line:        "hello",
			lineData:    &LineData{Indent: 0},
			expectError: true,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			err := ParseLine(tt.line, tt.lineData)

			if tt.expectError {
				if err == nil {
					t.Errorf("Expected an error, but got nil")
				}
				return
			}

			if err != nil {
				t.Errorf("Unexpected error: %v", err)
			}

			if *tt.lineData != *tt.expected {
				t.Errorf("Expected %v, but got %v", *tt.expected, *tt.lineData)
			}
		})
	}
}