package com.svnlog.web.service;

import java.nio.file.Path;
import java.time.Instant;

import org.junit.jupiter.api.Assertions;
import org.junit.jupiter.api.Test;
import org.junit.jupiter.api.io.TempDir;

import com.svnlog.web.model.TaskInfo;
import com.svnlog.web.model.TaskStatus;

import okio.Buffer;

class AiWorkflowServiceTest {

    @TempDir
    Path tempDir;

    private AiApiService buildAiApiService(SettingsService settingsService) {
        return new AiApiService(settingsService);
    }

    private ExcelExportService buildExcelExportService() {
        return new ExcelExportService();
    }

    @Test
    void shouldResolveDeepSeekProviderByDefault() {
        final OutputFileService outputFileService = buildOutputFileService();
        final SettingsService settingsService = buildSettingsService(outputFileService);
        final AiApiService aiApiService = buildAiApiService(settingsService);
        new AiWorkflowService(
                outputFileService,
                new AiInputValidator(),
                aiApiService,
                buildExcelExportService()
        );

        // DeepSeek provider：通过请求临时传入 key 来解析 context（不依赖内置默认 key）
        final AiApiService.AiProviderContext context = aiApiService.resolveProviderContext("sk-test-key");

        Assertions.assertEquals(SettingsService.PROVIDER_DEEPSEEK, context.getProvider());
        Assertions.assertEquals("deepseek-chat", context.getStageOneModel());
        Assertions.assertEquals("deepseek-reasoner", context.getStageTwoModel());
    }

    @Test
    void shouldResolveOpenAiCompatibleModelsAndUrl() {
        final OutputFileService outputFileService = buildOutputFileService();
        final SettingsService settingsService = buildSettingsService(outputFileService);
        settingsService.updateSettings(
                null,
                SettingsService.PROVIDER_OPENAI_COMPATIBLE,
                "http://127.0.0.1:5001/v1/",
                "sk-openai-test",
                "deepseek-v4-flash",
                "deepseek-v4-pro",
                null,
                null,
                null,
                null
        );
        final AiApiService aiApiService = buildAiApiService(settingsService);
        final AiWorkflowService service = new AiWorkflowService(
                outputFileService, new AiInputValidator(), aiApiService, buildExcelExportService()
        );

        final AiApiService.AiProviderContext context = aiApiService.resolveProviderContext(null);

        Assertions.assertEquals(SettingsService.PROVIDER_OPENAI_COMPATIBLE, context.getProvider());
        Assertions.assertEquals("http://127.0.0.1:5001/v1/chat/completions", context.getApiUrl());
        Assertions.assertEquals("deepseek-v4-flash", context.getStageOneModel());
        Assertions.assertEquals("deepseek-v4-pro", context.getStageTwoModel());
    }

    @Test
    void shouldFailFastWhenOpenAiCompatibleBaseUrlMissing() {
        final OutputFileService outputFileService = buildOutputFileService();
        final AiApiService aiApiService = buildAiApiService(
                new StubSettingsService(outputFileService, "   ", "sk-openai-test")
        );

        final IllegalStateException error = Assertions.assertThrows(
                IllegalStateException.class,
                () -> aiApiService.resolveProviderContext(null)
        );

        Assertions.assertTrue(error.getMessage().contains("OpenAI兼容 Base URL"));
    }

    @Test
    void shouldParseCompatibleStreamWhenOnlyContentIsReturned() throws Exception {
        final OutputFileService outputFileService = buildOutputFileService();
        final SettingsService settingsService = buildSettingsService(outputFileService);
        settingsService.updateSettings(
                null,
                SettingsService.PROVIDER_OPENAI_COMPATIBLE,
                "http://127.0.0.1:5001/v1",
                "sk-openai-test",
                "deepseek-v4-flash",
                "deepseek-v4-pro",
                null,
                null,
                null,
                null
        );
        final AiApiService aiApiService = buildAiApiService(settingsService);
        final AiApiService.AiProviderContext providerContext = aiApiService.resolveProviderContext(null);
        final TaskContext taskContext = new TaskContext(buildTaskInfo(), null, null);
        final Buffer buffer = new Buffer()
                .writeUtf8("data: {\"choices\":[{\"delta\":{\"content\":\"{\\\"items\\\":[\"}}]}\n")
                .writeUtf8("data: {\"choices\":[{\"delta\":{\"content\":\"{\\\"summary\\\":\\\"done\\\"}\"}}]}\n")
                .writeUtf8("data: {\"choices\":[{\"delta\":{\"content\":\"]}\"},\"finish_reason\":\"stop\"}]}\n")
                .writeUtf8("data: [DONE]\n");

        final AiApiService.AiStreamResult result = aiApiService.readStreamingResponse(
                buffer,
                taskContext,
                providerContext,
                "deepseek-v4-flash",
                8000
        );

        Assertions.assertEquals("{\"items\":[{\"summary\":\"done\"}]}", result.getAnswer());
        Assertions.assertEquals("stop", result.getFinishReason());
    }

    private OutputFileService buildOutputFileService() {
        final OutputFileService outputFileService = new OutputFileService();
        outputFileService.setOutputRoot(tempDir.resolve("outputs").toString());
        return outputFileService;
    }

    private TaskInfo buildTaskInfo() {
        final TaskInfo taskInfo = new TaskInfo();
        taskInfo.setTaskId("task-1");
        taskInfo.setStatus(TaskStatus.RUNNING);
        taskInfo.setCreatedAt(Instant.now());
        taskInfo.setUpdatedAt(Instant.now());
        return taskInfo;
    }

    private SettingsService buildSettingsService(OutputFileService outputFileService) {
        final RepositoryConfigService repositoryConfigService = buildRepositoryConfigService(outputFileService);
        final SvnPresetService svnPresetService = new SvnPresetService(repositoryConfigService);
        return new SettingsService(outputFileService, new SettingsPersistenceService(), svnPresetService, repositoryConfigService);
    }

    private RepositoryConfigService buildRepositoryConfigService(OutputFileService outputFileService) {
        final RepositoryConfigService repositoryConfigService = new RepositoryConfigService(outputFileService);
        repositoryConfigService.init();
        return repositoryConfigService;
    }

    private static final class StubSettingsService extends SettingsService {
        private final String openaiBaseUrl;
        private final String openaiApiKey;

        private StubSettingsService(OutputFileService outputFileService, String openaiBaseUrl, String openaiApiKey) {
            super(
                    outputFileService,
                    new SettingsPersistenceService(),
                    new SvnPresetService(new RepositoryConfigService(outputFileService)),
                    new RepositoryConfigService(outputFileService)
            );
            this.openaiBaseUrl = openaiBaseUrl;
            this.openaiApiKey = openaiApiKey;
        }

        @Override
        public String getProvider() {
            return SettingsService.PROVIDER_OPENAI_COMPATIBLE;
        }

        @Override
        public String getOpenaiBaseUrl() {
            return openaiBaseUrl;
        }

        @Override
        public String getOpenaiApiKey() {
            return openaiApiKey;
        }
    }
}