package com.yunhai.question.service;

import com.fasterxml.jackson.databind.ObjectMapper;
import com.yunhai.question.entity.PullCursor;
import com.yunhai.question.entity.Questionnaire;
import com.yunhai.question.fc.FormCenterClient;
import com.yunhai.question.repository.AnswerProjectionRepository;
import com.yunhai.question.repository.PullCursorRepository;
import com.yunhai.question.repository.QuestionnaireRepository;
import org.junit.jupiter.api.BeforeEach;
import org.junit.jupiter.api.Test;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.autoconfigure.orm.jpa.DataJpaTest;
import org.springframework.transaction.PlatformTransactionManager;
import org.springframework.transaction.support.TransactionTemplate;

import java.util.Arrays;
import java.util.HashMap;
import java.util.LinkedHashMap;
import java.util.Map;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertNull;
import static org.junit.jupiter.api.Assertions.assertTrue;
import static org.mockito.ArgumentMatchers.any;
import static org.mockito.ArgumentMatchers.anyInt;
import static org.mockito.ArgumentMatchers.anyString;
import static org.mockito.ArgumentMatchers.eq;
import static org.mockito.Mockito.mock;
import static org.mockito.Mockito.times;
import static org.mockito.Mockito.verify;
import static org.mockito.Mockito.when;

/**
 * 投影服务单测（H2 真库 + mock FormCenterClient）——任务书点名的四件之二/三：
 * 游标推进、投影幂等 upsert（重放同窗口不产生重复行、不重复累计 seen_count）、墓碑翻位。
 */
@DataJpaTest
class ProjectionServiceTest {

    private static final Long SCH_ID = 990001L;
    private static final String FORM_UUID = "f0123456789abcdef0123456789abcde";

    @Autowired
    private QuestionnaireRepository questionnaireRepository;
    @Autowired
    private PullCursorRepository pullCursorRepository;
    @Autowired
    private AnswerProjectionRepository answerProjectionRepository;
    @Autowired
    private PlatformTransactionManager txManager;

    private FormCenterClient fc;
    private ProjectionService service;

    @BeforeEach
    void setUp() {
        fc = mock(FormCenterClient.class);
        service = new ProjectionService(questionnaireRepository, pullCursorRepository,
                answerProjectionRepository, fc, new ObjectMapper(),
                new TransactionTemplate(txManager), 10, 100);
    }

    private Questionnaire questionnaire(String formUuid) {
        Questionnaire q = new Questionnaire();
        q.setSchId(SCH_ID);
        q.setFormUuid(formUuid);
        q.setFormCode("q-001");
        q.setTitleSnapshot("测试问卷");
        q.setStatus(Questionnaire.STATUS_COLLECTING);
        q.setAnonymous(false);
        return questionnaireRepository.save(q);
    }

    /** FC 行（snake_case 闭集） */
    private static Map<String, Object> fcRow(String uuid, boolean deleted, Object... valuePairs) {
        Map<String, Object> values = new LinkedHashMap<>();
        for (int i = 0; i + 1 < valuePairs.length; i += 2) {
            values.put(String.valueOf(valuePairs[i]), valuePairs[i + 1]);
        }
        Map<String, Object> row = new HashMap<>();
        row.put("answer_uuid", uuid);
        row.put("form_uuid", FORM_UUID);
        row.put("submitter_id", 101);
        row.put("subject_id", null);
        row.put("status", "待处理");
        row.put("values", values);
        row.put("create_time", "2026-10-21 10:00:00");
        row.put("update_time", "2026-10-21 10:00:00");
        row.put("is_deleted", deleted ? 1 : 0);
        return row;
    }

    /** after=afterArg 的页（rows 可空） */
    private void stubPage(String afterArg, String nextCursor, Map<String, Object>... rows) {
        when(fc.pullAnswers(any(), anyString(), eq(afterArg), anyInt()))
                .thenReturn(new FormCenterClient.AnswersPage(Arrays.asList(rows), nextCursor));
    }

    @Test
    void advancesCursorAcrossPages() {
        questionnaire(FORM_UUID);
        stubPage(null, "a1", fcRow("a1", false, "q1", "m"));
        stubPage("a1", "a2", fcRow("a2", false, "q1", "f"));
        stubPage("a2", null);

        service.pullOnce(SCH_ID, FORM_UUID);
        assertEquals("a2", pullCursorRepository.findById(FORM_UUID).get().getCursor());
        assertEquals(2, answerProjectionRepository.countByFormUuid(FORM_UUID));

        // 第二轮：游标从 a2 起，只拉增量
        stubPage("a2", "a3", fcRow("a3", false, "q1", "m"));
        stubPage("a3", null);
        int fresh = service.pullOnce(SCH_ID, FORM_UUID);
        assertEquals(1, fresh);
        assertEquals("a3", pullCursorRepository.findById(FORM_UUID).get().getCursor());
        assertEquals(3, answerProjectionRepository.countByFormUuid(FORM_UUID));
        // 增量轮从 a2 起——验证游标确已推进（a2 之前的窗口未再请求）
        verify(fc, times(1)).pullAnswers(any(), anyString(), eq((String) null), anyInt());
        verify(fc, times(1)).pullAnswers(any(), anyString(), eq("a1"), anyInt());
        verify(fc, times(2)).pullAnswers(any(), anyString(), eq("a2"), anyInt());
    }

    @Test
    void replaySameWindowIsIdempotent() {
        questionnaire(FORM_UUID);
        stubPage(null, "a1", fcRow("a1", false, "q1", "m"));
        stubPage("a1", null);
        service.pullOnce(SCH_ID, FORM_UUID);

        // 模拟游标回拨（运维/异常后重放）：从头再拉同窗口 + 新行 a2——a1 重放不算新行
        PullCursor rollback = pullCursorRepository.findById(FORM_UUID).orElseThrow(AssertionError::new);
        rollback.setCursor(null);
        pullCursorRepository.saveAndFlush(rollback);
        stubPage(null, "a2", fcRow("a1", false, "q1", "m"), fcRow("a2", false, "q1", "f"));
        stubPage("a2", null);
        int fresh = service.pullOnce(SCH_ID, FORM_UUID);

        assertEquals(1, fresh);
        assertEquals(2, answerProjectionRepository.countByFormUuid(FORM_UUID));
        PullCursor cursor = pullCursorRepository.findById(FORM_UUID).get();
        assertEquals(2L, cursor.getSeenCount(), "重放行不重复累计 seen_count");
        assertEquals("a2", cursor.getCursor());
    }

    @Test
    void tombstoneFlipsIsDeletedWithoutDroppingRow() {
        questionnaire(FORM_UUID);
        stubPage(null, "a1", fcRow("a1", false, "q1", "m"));
        stubPage("a1", null);
        service.pullOnce(SCH_ID, FORM_UUID);
        assertEquals(1, answerProjectionRepository.countByFormUuidAndIsDeletedFalse(FORM_UUID));

        // FC 侧软删 → 墓碑行：同一 answer_uuid，is_deleted=1
        stubPage("a1", null, fcRow("a1", true, "q1", "m"));
        service.pullOnce(SCH_ID, FORM_UUID);

        assertEquals(0, answerProjectionRepository.countByFormUuidAndIsDeletedFalse(FORM_UUID));
        assertEquals(1, answerProjectionRepository.countByFormUuid(FORM_UUID), "墓碑不删行");
        assertTrue(answerProjectionRepository.findByAnswerUuid("a1").getIsDeleted());
        assertEquals(1L, pullCursorRepository.findById(FORM_UUID).get().getSeenCount(),
                "墓碑是已见行的翻位，不计新行");
    }

    @Test
    void updatedRowKeepsSingleRow() {
        questionnaire(FORM_UUID);
        stubPage(null, "a1", fcRow("a1", false, "q1", "m"));
        stubPage("a1", null);
        service.pullOnce(SCH_ID, FORM_UUID);

        // 状态被 FC 侧更新后重放：同 uuid 更新而非插入
        Map<String, Object> updated = fcRow("a1", false, "q1", "f");
        updated.put("status", "已处理");
        stubPage("a1", null, updated);
        service.pullOnce(SCH_ID, FORM_UUID);

        assertEquals(1, answerProjectionRepository.countByFormUuid(FORM_UUID));
        assertEquals("已处理", answerProjectionRepository.findByAnswerUuid("a1").getStatus());
        assertEquals(1L, pullCursorRepository.findById(FORM_UUID).get().getSeenCount());
    }

    @Test
    void firstPullWithEmptyWindowInitializesCursor() {
        questionnaire(FORM_UUID);
        stubPage(null, null);

        int fresh = service.pullOnce(SCH_ID, FORM_UUID);

        assertEquals(0, fresh);
        PullCursor cursor = pullCursorRepository.findById(FORM_UUID).get();
        assertNull(cursor.getCursor(), "空窗口不推进游标（null=从未有行）");
        assertEquals("OK", cursor.getLastStatus());
    }

    @Test
    void reconciliationWarnsOnSeenCountDrift() {
        questionnaire(FORM_UUID);
        stubPage(null, "a1", fcRow("a1", false, "q1", "m"));
        stubPage("a1", null);
        service.pullOnce(SCH_ID, FORM_UUID);

        // 模拟投影表被外部删行：seen_count=1 但投影总量=0 → 漂移告警路径（不抛错）
        answerProjectionRepository.deleteAll();
        service.checkReconciliation(FORM_UUID, pullCursorRepository.findById(FORM_UUID).get());
        assertEquals(0, answerProjectionRepository.countByFormUuid(FORM_UUID));
    }
}