package parse_test

import (
	"strings"
	"testing"

	"qbank/internal/parse"
)

func TestChunk(t *testing.T) {
	t.Run("small text stays in one chunk", func(t *testing.T) {
		text := "Para one.\n\nPara two.\n\nPara three."
		chunks := parse.Chunk(text, 1000)
		if len(chunks) != 1 {
			t.Errorf("want 1 chunk, got %d: %v", len(chunks), chunks)
		}
		if !strings.Contains(chunks[0], "Para one") || !strings.Contains(chunks[0], "Para three") {
			t.Errorf("content lost: %q", chunks[0])
		}
	})

	t.Run("paragraphs split when over limit", func(t *testing.T) {
		para := strings.Repeat("x", 600)
		text := para + "\n\n" + para + "\n\n" + para
		chunks := parse.Chunk(text, 1000)
		if len(chunks) < 2 {
			t.Errorf("want ≥2 chunks for 1800-rune input with 1000 limit, got %d", len(chunks))
		}
		// No chunk should combine paragraphs past the limit
		for i, c := range chunks {
			if len([]rune(c)) > 1200 {
				t.Errorf("chunk %d is %d runes, too large", i, len([]rune(c)))
			}
		}
	})

	t.Run("single oversized paragraph kept as own chunk", func(t *testing.T) {
		bigPara := strings.Repeat("x", 2000)
		chunks := parse.Chunk(bigPara, 1000)
		if len(chunks) != 1 {
			t.Errorf("want 1 chunk for single oversized para, got %d", len(chunks))
		}
	})

	t.Run("empty paragraphs ignored", func(t *testing.T) {
		text := "\n\nPara one.\n\n\n\nPara two.\n\n"
		chunks := parse.Chunk(text, 1000)
		if len(chunks) != 1 {
			t.Errorf("want 1 chunk after ignoring blanks, got %d", len(chunks))
		}
	})
}