package com.superbiz.agent.service;

import com.superbiz.agent.dto.Frontmatter;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;

import java.util.List;

import static org.junit.jupiter.api.Assertions.*;

/**
 * FrontmatterParser 单元测试
 */
class FrontmatterParserTest {

    private FrontmatterParser parser;

    @BeforeEach
    void setUp() {
        parser = new FrontmatterParser();
    }

    @Test
    void testHasFrontmatter_withValidFrontmatter() {
        String content = "---\ntitle: Test\n---\nContent";
        assertTrue(parser.hasFrontmatter(content));
    }

    @Test
    void testHasFrontmatter_withoutFrontmatter() {
        String content = "# Just a title\nContent";
        assertFalse(parser.hasFrontmatter(content));
    }

    @Test
    void testHasFrontmatter_nullContent() {
        assertFalse(parser.hasFrontmatter(null));
    }

    @Test
    void testHasFrontmatter_emptyContent() {
        assertFalse(parser.hasFrontmatter(""));
    }

    @Test
    void testParse_validFrontmatter() {
        String content = """
            ---
            title: 支付网关错误码
            keywords: [ERR_TIMEOUT, 超时, 支付网关]
            summary: 记录了支付网关所有核心错误码
            category: api
            ---

            # 正文内容
            """;

        Frontmatter result = parser.parse(content);

        assertNotNull(result);
        assertEquals("支付网关错误码", result.getTitle());
        assertEquals(3, result.getKeywords().size());
        assertTrue(result.getKeywords().contains("ERR_TIMEOUT"));
        assertEquals("记录了支付网关所有核心错误码", result.getSummary());
        assertEquals("api", result.getCategory());
    }

    @Test
    void testParse_withoutFrontmatter() {
        String content = "# Just content\nNo frontmatter here";
        assertNull(parser.parse(content));
    }

    @Test
    void testParse_missingRequiredFields() {
        String content = """
            ---
            title: Only Title
            ---
            Content
            """;

        // 缺少 keywords 和 summary，应返回 null
        Frontmatter result = parser.parse(content);
        assertNull(result);
    }

    @Test
    void testParse_malformedYaml() {
        String content = """
            ---
            title: Test
            keywords: [unclosed array
            ---
            Content
            """;

        // YAML 格式错误，应返回 null
        Frontmatter result = parser.parse(content);
        assertNull(result);
    }

    @Test
    void testParse_noClosingDelimiter() {
        String content = """
            ---
            title: Test
            keywords: [test]
            summary: Test summary

            Content without closing ---
            """;

        // 缺少结束标记，应返回 null
        Frontmatter result = parser.parse(content);
        assertNull(result);
    }

    @Test
    void testParse_windowsLineEndings() {
        String content = "---\r\ntitle: Test\r\nkeywords: [test]\r\nsummary: Summary\r\n---\r\nContent";

        Frontmatter result = parser.parse(content);

        assertNotNull(result);
        assertEquals("Test", result.getTitle());
    }

    @Test
    void testParse_withOptionalFields() {
        String content = """
            ---
            title: Test Document
            keywords: [test, doc]
            summary: A test document
            version: 1.0.0
            author: Test Author
            ---
            Content
            """;

        Frontmatter result = parser.parse(content);

        assertNotNull(result);
        assertEquals("Test Document", result.getTitle());
        assertEquals("1.0.0", result.getVersion());
        assertEquals("Test Author", result.getAuthor());
    }

    @Test
    void testParse_withRetrievalMetadata() {
        String content = """
            ---
            title: MySQL Connection Pool
            keywords: [connection pool, HikariCP]
            summary: Diagnose exhausted MySQL connection pools
            category: database
            source: mysql-connection-pool
            breadcrumb: Database > MySQL > Connection Pool
            kb_scope: rag-eval
            ---
            Content
            """;

        Frontmatter result = parser.parse(content);

        assertNotNull(result);
        assertEquals("mysql-connection-pool", result.getSource());
        assertEquals("Database > MySQL > Connection Pool", result.getBreadcrumb());
        assertEquals("rag-eval", result.getKbScope());
    }

    @Test
    void testStripFrontmatter_returnsMarkdownBodyOnly() {
        String content = """
            ---
            title: Test
            keywords: [frontmatter-only]
            summary: Summary
            ---

            # Body

            Body content
            """;

        String body = parser.stripFrontmatter(content);

        assertFalse(body.contains("frontmatter-only"));
        assertTrue(body.startsWith("# Body"));
        assertTrue(body.contains("Body content"));
    }
}