package vectorstore_test

import (
	"strings"
	"testing"

	"github.com/mathiasbq/hyperguild/ingestion/internal/vectorstore"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
)

func TestChunkMarkdown_ShortFileFitsInOne(t *testing.T) {
	out := vectorstore.ChunkMarkdown("Just a short paragraph.\n", 4000)
	require.Len(t, out, 1)
	assert.Equal(t, "Just a short paragraph.\n", out[0])
}

func TestChunkMarkdown_SplitsAtHeadings(t *testing.T) {
	src := "# Top\n\nintro\n\n## A\n\nbody a\n\n## B\n\nbody b\n"
	out := vectorstore.ChunkMarkdown(src, 50) // tiny limit forces per-section split

	assert.GreaterOrEqual(t, len(out), 2, "should split at H2 boundaries")
	// Each chunk should start with a heading (top-level intro chunk OK without one)
	for i, c := range out {
		if i == 0 {
			continue
		}
		assert.True(t, strings.HasPrefix(strings.TrimSpace(c), "#"),
			"non-first chunk %d should start with heading: %q", i, c)
	}
}

func TestChunkMarkdown_FurtherSplitsOversizedSection(t *testing.T) {
	// One H2 section with 4 paragraphs of ~80 chars each, limit 100.
	src := "## big\n\n" +
		strings.Repeat("paragraph one is moderately long.\n\n", 1) +
		strings.Repeat("paragraph two also moderately long.\n\n", 1) +
		strings.Repeat("paragraph three is moderately long.\n\n", 1) +
		strings.Repeat("paragraph four is moderately long.\n\n", 1)
	out := vectorstore.ChunkMarkdown(src, 100)

	assert.Greater(t, len(out), 1, "oversized section should sub-split at paragraph boundaries")
	for i, c := range out {
		assert.LessOrEqual(t, len(c), 200,
			"chunk %d exceeds 2x maxBytes: %d", i, len(c))
	}
}

func TestChunkMarkdown_PreservesContent(t *testing.T) {
	src := "# H1\n\nfirst section body.\n\n## H2a\n\nsecond section body.\n\n## H2b\n\nthird section body.\n"
	out := vectorstore.ChunkMarkdown(src, 50)
	joined := strings.Join(out, "")
	// All non-whitespace tokens from src must appear in the joined output
	for _, token := range []string{"H1", "first", "H2a", "second", "H2b", "third"} {
		assert.Contains(t, joined, token, "token %q missing after chunking", token)
	}
}

func TestChunkMarkdown_NumberedSuffix(t *testing.T) {
	out := vectorstore.NumberChunks("knowledge/foo.md", []string{"a", "b", "c"})
	require.Len(t, out, 3)
	assert.Equal(t, "knowledge/foo.md#0001", out[0].Path)
	assert.Equal(t, "knowledge/foo.md#0002", out[1].Path)
	assert.Equal(t, "knowledge/foo.md#0003", out[2].Path)
	assert.Equal(t, "a", out[0].Content)
}

func TestParentPath_StripsChunkSuffix(t *testing.T) {
	assert.Equal(t, "knowledge/foo.md", vectorstore.ParentPath("knowledge/foo.md#0001"))
	assert.Equal(t, "knowledge/foo.md", vectorstore.ParentPath("knowledge/foo.md"))
	assert.Equal(t, "wiki/a/b.md", vectorstore.ParentPath("wiki/a/b.md#9999"))
}