// Copyright 2026 The Gitea Authors. All rights reserved.
// SPDX-License-Identifier: MIT

package gitdiff

import (
	"bytes"
	"strconv"
	"testing"

	"code.gitea.io/gitea/modules/translation"

	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
)

func TestBuildBlobExcerptDiffSection(t *testing.T) {
	data := &bytes.Buffer{}
	for i := range 100 {
		data.WriteString("a = " + strconv.Itoa(i+1) + "\n")
	}

	locale := translation.MockLocale{}
	lineMiddle := 50
	diffSection, err := BuildBlobExcerptDiffSection("a.py", bytes.NewReader(data.Bytes()), BlobExcerptOptions{
		LeftIndex:     lineMiddle,
		RightIndex:    lineMiddle,
		LeftHunkSize:  10,
		RightHunkSize: 10,
		Direction:     "up",
	})
	require.NoError(t, err)
	assert.Len(t, diffSection.highlightedRightLines.value, BlobExcerptChunkSize)
	assert.NotEmpty(t, diffSection.highlightedRightLines.value[lineMiddle-BlobExcerptChunkSize-1])
	assert.NotEmpty(t, diffSection.highlightedRightLines.value[lineMiddle-2]) // 0-based

	diffInline := diffSection.GetComputedInlineDiffFor(diffSection.Lines[1], locale)
	assert.Equal(t, `<span class="n">a</span> <span class="o">=</span> <span class="mi">30</span>`+"\n", string(diffInline.Content))
}