package plane_v2

import (
	"bytes"
	"encoding/json"
	"fmt"
	"fwh-toolbox-server/config"
	"io"
	"mime/multipart"
	"net/http"
	"net/http/cookiejar"
	"net/url"
	"strings"
	"sync"
	"time"

	"go.uber.org/zap"
)

// Plane v2 Web API客户端 - 使用Session+CSRF认证（Django SessionAuthentication）

const (
	webTimeout time.Duration = 60 * time.Second // 请求超时60s
)

var (
	webBaseURL      string
	webEmail        string
	webPassword      string
	webWorkspaceSlug string
	webProjectId     string
	webLabelBugId      string
	webLabelFeatureId  string
	webLabelFeedbackId string
	webCsrfToken    string
	webClient       *http.Client
	webLoginMu      sync.Mutex
)

// planeWebResponse 封装Plane Web HTTP响应
type planeWebResponse struct {
	StatusCode int
	Status     string
	Body       []byte
}

// PlaneWebHttpInit 初始化Plane Web HTTP客户端配置
func PlaneWebHttpInit(cfg *config.PlaneWebApiConfig) {
	webBaseURL = strings.TrimRight(cfg.Host, "/")
	webEmail = cfg.Email
	webPassword = cfg.Password
	webWorkspaceSlug = cfg.WorkspaceSlug
	webProjectId = cfg.ProjectId
	webLabelBugId = cfg.LabelBugId
	webLabelFeatureId = cfg.LabelFeatureId
	webLabelFeedbackId = cfg.LabelFeedbackId

	jar, err := cookiejar.New(nil)
	if err != nil {
		zap.L().Fatal("[PlaneWeb] 创建CookieJar失败", zap.Error(err))
	}

	webClient = &http.Client{
		Timeout: webTimeout,
		Jar:     jar,
		CheckRedirect: func(req *http.Request, via []*http.Request) error {
			return http.ErrUseLastResponse
		},
	}

	// 初始化时执行登录
	if err := webLogin(); err != nil {
		zap.L().Error("[PlaneWeb] 初始化登录失败", zap.Error(err))
	}
}

// GetWorkspaceSlug 获取WorkspaceSlug
func GetWorkspaceSlug() string {
	return webWorkspaceSlug
}

// GetProjectId 获取ProjectId
func GetProjectId() string {
	return webProjectId
}

// GetLabelBugId 获取Bug标签ID
func GetWebLabelBugId() string {
	return webLabelBugId
}

// GetLabelFeatureId 获取Feature标签ID
func GetWebLabelFeatureId() string {
	return webLabelFeatureId
}

// GetLabelFeedbackId 获取Feedback标签ID
func GetWebLabelFeedbackId() string {
	return webLabelFeedbackId
}

// isWebSuccess 判断HTTP状态码是否表示成功(2xx或3xx重定向)
func isWebSuccess(statusCode int) bool {
	return statusCode >= 200 && statusCode < 300
}

// webLogin 执行登录流程：获取CSRF Token → 登录获取Session
func webLogin() error {
	webLoginMu.Lock()
	defer webLoginMu.Unlock()

	zap.L().Info("[PlaneWeb] 开始登录流程")

	// Step 1: GET /auth/get-csrf-token/ 获取CSRF Token
	csrfURL := webBaseURL + "/auth/get-csrf-token/"
	req, err := http.NewRequest(http.MethodGet, csrfURL, nil)
	if err != nil {
		return fmt.Errorf("创建CSRF请求失败: %w", err)
	}
	req.Header.Set("Referer", webBaseURL)

	resp, err := webClient.Do(req)
	if err != nil {
		return fmt.Errorf("获取CSRF Token请求失败: %w", err)
	}
	defer resp.Body.Close()

	body, err := io.ReadAll(resp.Body)
	if err != nil {
		return fmt.Errorf("读取CSRF响应失败: %w", err)
	}

	if resp.StatusCode != http.StatusOK {
		return fmt.Errorf("获取CSRF Token失败, status=%d, body=%s", resp.StatusCode, string(body))
	}

	// 解析CSRF Token
	var csrfResp struct {
		CsrfToken string `json:"csrf_token"`
	}
	if err := json.Unmarshal(body, &csrfResp); err != nil {
		return fmt.Errorf("解析CSRF Token响应失败: %w", err)
	}
	webCsrfToken = csrfResp.CsrfToken

	zap.L().Debug("[PlaneWeb] 获取CSRF Token成功", zap.String("token", webCsrfToken[:8]+"..."))

	// Step 2: POST /auth/sign-in/ 登录
	signInURL := webBaseURL + "/auth/sign-in/"
	formData := url.Values{}
	formData.Set("email", webEmail)
	formData.Set("password", webPassword)

	req, err = http.NewRequest(http.MethodPost, signInURL, strings.NewReader(formData.Encode()))
	if err != nil {
		return fmt.Errorf("创建登录请求失败: %w", err)
	}

	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
	req.Header.Set("Referer", webBaseURL)
	req.Header.Set("X-CSRFToken", webCsrfToken)
	req.AddCookie(&http.Cookie{Name: "csrftoken", Value: webCsrfToken})

	resp, err = webClient.Do(req)
	if err != nil {
		return fmt.Errorf("登录请求失败: %w", err)
	}
	defer resp.Body.Close()

	// 登录成功返回302
	if resp.StatusCode != http.StatusFound {
		loginBody, _ := io.ReadAll(resp.Body)
		return fmt.Errorf("登录失败, status=%d, body=%s", resp.StatusCode, string(loginBody))
	}

	// 验证session-id cookie是否已设置
	parsedURL, _ := url.Parse(webBaseURL)
	cookies := webClient.Jar.Cookies(parsedURL)
	hasSession := false
	for _, c := range cookies {
		if c.Name == "session-id" {
			hasSession = true
			break
		}
	}

	if !hasSession {
		return fmt.Errorf("登录后未获取到session-id cookie")
	}

	zap.L().Info("[PlaneWeb] 登录成功")
	return nil
}

// webEnsureAuth 确保已认证，如果收到401/403则重新登录并重试
func webEnsureAuth(doRequest func() (*planeWebResponse, error)) (*planeWebResponse, error) {
	resp, err := doRequest()
	if err != nil {
		return nil, err
	}

	// 如果是401或403，尝试重新登录后重试
	if resp.StatusCode == http.StatusUnauthorized || resp.StatusCode == http.StatusForbidden {
		zap.L().Warn("[PlaneWeb] 收到认证错误，尝试重新登录", zap.Int("statusCode", resp.StatusCode))

		if loginErr := webLogin(); loginErr != nil {
			return nil, fmt.Errorf("重新登录失败: %w", loginErr)
		}

		// 重试请求
		return doRequest()
	}

	return resp, nil
}

// planeWebGet 发送GET请求到Plane Web API
func planeWebGet(relativeURL string) (*planeWebResponse, error) {
	return webEnsureAuth(func() (*planeWebResponse, error) {
		reqURL := webBaseURL + relativeURL

		zap.L().Debug("[PlaneWeb] HttpGet", zap.String("url", reqURL))

		req, err := http.NewRequest(http.MethodGet, reqURL, nil)
		if err != nil {
			return nil, fmt.Errorf("创建请求失败: %w", err)
		}

		req.Header.Set("Accept", "application/json")
		req.Header.Set("Referer", webBaseURL)

		resp, err := webClient.Do(req)
		if err != nil {
			return nil, fmt.Errorf("请求失败: %w", err)
		}
		defer resp.Body.Close()

		body, err := io.ReadAll(resp.Body)
		if err != nil {
			return nil, fmt.Errorf("读取响应失败: %w", err)
		}

		return &planeWebResponse{
			StatusCode: resp.StatusCode,
			Status:     resp.Status,
			Body:       body,
		}, nil
	})
}

// planeWebPost 发送POST请求到Plane Web API（JSON）
func planeWebPost(relativeURL string, reqBody any) (*planeWebResponse, error) {
	return webEnsureAuth(func() (*planeWebResponse, error) {
		reqURL := webBaseURL + relativeURL

		zap.L().Debug("[PlaneWeb] HttpPost", zap.String("url", reqURL))

		jsonData, err := json.Marshal(reqBody)
		if err != nil {
			return nil, fmt.Errorf("序列化请求体失败: %w", err)
		}

		req, err := http.NewRequest(http.MethodPost, reqURL, bytes.NewReader(jsonData))
		if err != nil {
			return nil, fmt.Errorf("创建请求失败: %w", err)
		}

		req.Header.Set("Content-Type", "application/json")
		req.Header.Set("Accept", "application/json")
		req.Header.Set("Referer", webBaseURL)
		req.Header.Set("X-CSRFToken", webCsrfToken)

		resp, err := webClient.Do(req)
		if err != nil {
			return nil, fmt.Errorf("请求失败: %w", err)
		}
		defer resp.Body.Close()

		body, err := io.ReadAll(resp.Body)
		if err != nil {
			return nil, fmt.Errorf("读取响应失败: %w", err)
		}

		return &planeWebResponse{
			StatusCode: resp.StatusCode,
			Status:     resp.Status,
			Body:       body,
		}, nil
	})
}

// planeWebPatch 发送PATCH请求到Plane Web API（JSON）
func planeWebPatch(relativeURL string, reqBody any) (*planeWebResponse, error) {
	return webEnsureAuth(func() (*planeWebResponse, error) {
		reqURL := webBaseURL + relativeURL

		zap.L().Debug("[PlaneWeb] HttpPatch", zap.String("url", reqURL))

		jsonData, err := json.Marshal(reqBody)
		if err != nil {
			return nil, fmt.Errorf("序列化请求体失败: %w", err)
		}

		req, err := http.NewRequest(http.MethodPatch, reqURL, bytes.NewReader(jsonData))
		if err != nil {
			return nil, fmt.Errorf("创建请求失败: %w", err)
		}

		req.Header.Set("Content-Type", "application/json")
		req.Header.Set("Accept", "application/json")
		req.Header.Set("Referer", webBaseURL)
		req.Header.Set("X-CSRFToken", webCsrfToken)

		resp, err := webClient.Do(req)
		if err != nil {
			return nil, fmt.Errorf("请求失败: %w", err)
		}
		defer resp.Body.Close()

		body, err := io.ReadAll(resp.Body)
		if err != nil {
			return nil, fmt.Errorf("读取响应失败: %w", err)
		}

		return &planeWebResponse{
			StatusCode: resp.StatusCode,
			Status:     resp.Status,
			Body:       body,
		}, nil
	})
}

// planeWebDelete 发送DELETE请求到Plane Web API
func planeWebDelete(relativeURL string) (*planeWebResponse, error) {
	return webEnsureAuth(func() (*planeWebResponse, error) {
		reqURL := webBaseURL + relativeURL

		zap.L().Debug("[PlaneWeb] HttpDelete", zap.String("url", reqURL))

		req, err := http.NewRequest(http.MethodDelete, reqURL, nil)
		if err != nil {
			return nil, fmt.Errorf("创建请求失败: %w", err)
		}

		req.Header.Set("Accept", "application/json")
		req.Header.Set("Referer", webBaseURL)
		req.Header.Set("X-CSRFToken", webCsrfToken)

		resp, err := webClient.Do(req)
		if err != nil {
			return nil, fmt.Errorf("请求失败: %w", err)
		}
		defer resp.Body.Close()

		body, err := io.ReadAll(resp.Body)
		if err != nil {
			return nil, fmt.Errorf("读取响应失败: %w", err)
		}

		return &planeWebResponse{
			StatusCode: resp.StatusCode,
			Status:     resp.Status,
			Body:       body,
		}, nil
	})
}

// planeWebPostForm 发送multipart/form-data POST请求到Plane Web API
func planeWebPostForm(relativeURL string, writeForm func(w *multipart.Writer) error) (*planeWebResponse, error) {
	return webEnsureAuth(func() (*planeWebResponse, error) {
		reqURL := webBaseURL + relativeURL

		zap.L().Debug("[PlaneWeb] HttpPostForm", zap.String("url", reqURL))

		var buf bytes.Buffer
		writer := multipart.NewWriter(&buf)

		if err := writeForm(writer); err != nil {
			return nil, fmt.Errorf("写入表单数据失败: %w", err)
		}
		writer.Close()

		req, err := http.NewRequest(http.MethodPost, reqURL, &buf)
		if err != nil {
			return nil, fmt.Errorf("创建请求失败: %w", err)
		}

		req.Header.Set("Content-Type", writer.FormDataContentType())
		req.Header.Set("Accept", "application/json")
		req.Header.Set("Referer", webBaseURL)
		req.Header.Set("X-CSRFToken", webCsrfToken)

		resp, err := webClient.Do(req)
		if err != nil {
			return nil, fmt.Errorf("请求失败: %w", err)
		}
		defer resp.Body.Close()

		body, err := io.ReadAll(resp.Body)
		if err != nil {
			return nil, fmt.Errorf("读取响应失败: %w", err)
		}

		return &planeWebResponse{
			StatusCode: resp.StatusCode,
			Status:     resp.Status,
			Body:       body,
		}, nil
	})
}