package handlers

import (
	"fmt"
	"net/http"
	"strconv"
	"time"

	"simple_portal/middleware"
	"simple_portal/models"
	"simple_portal/session"

	"github.com/gin-gonic/gin"
)

// HomeHandler renders the portal home page with enabled cards and search engine.
// 同时记录主页访问日志。
func HomeHandler(c *gin.Context) {
	cards, err := models.GetEnabledCards()
	if err != nil {
		c.HTML(http.StatusInternalServerError, "home.html", gin.H{"Error": "Failed to load cards"})
		return
	}

	searchEngine, err := models.GetSetting(models.SettingKeySearchEngine)
	if err != nil {
		searchEngine = models.SearchEngineGoogle
	}
	if searchEngine == "" {
		searchEngine = models.SearchEngineGoogle
	}

	// Fetch homepage configuration
	siteTitle, _ := models.GetSetting(models.SettingKeyHomepageTitle)
	if siteTitle == "" {
		siteTitle = models.DefaultHomepageTitle
	}

	siteSubtitle, _ := models.GetSetting(models.SettingKeyHomepageSubtitle)

	backgroundImage, _ := models.GetSetting(models.SettingKeyHomepageBackground)

	// 记录主页访问日志（异步，不影响页面渲染）
	ip := c.ClientIP()
	ua := c.Request.UserAgent()
	referer := c.Request.Referer()
	go func() {
		_ = models.CreateAccessLog(ip, ua, models.ActionTypeVisit, "", referer)
	}()

	c.HTML(http.StatusOK, "home.html", gin.H{
		"Title":           siteTitle,
		"Cards":           cards,
		"SearchEngine":    searchEngine,
		"SiteTitle":       siteTitle,
		"SiteSubtitle":    siteSubtitle,
		"BackgroundImage": backgroundImage,
	})
}

// CardClickHandler 处理卡片点击，记录访问日志后重定向到目标URL。
func CardClickHandler(c *gin.Context) {
	idStr := c.Param("id")
	id, err := strconv.Atoi(idStr)
	if err != nil {
		c.Redirect(http.StatusFound, "/")
		return
	}

	card, err := models.GetCardByID(id)
	if err != nil || card == nil {
		c.Redirect(http.StatusFound, "/")
		return
	}

	// 记录卡片点击日志
	ip := c.ClientIP()
	ua := c.Request.UserAgent()
	referer := c.Request.Referer()
	cardTitle := card.Title
	go func() {
		_ = models.CreateAccessLog(ip, ua, models.ActionTypeClick, cardTitle, referer)
	}()

	c.Redirect(http.StatusFound, card.URL)
}

// SearchHandler 处理搜索请求，记录搜索日志后重定向到搜索引擎。
func SearchHandler(c *gin.Context) {
	query := c.Query("q")
	if query == "" {
		c.Redirect(http.StatusFound, "/")
		return
	}

	searchEngine, err := models.GetSetting(models.SettingKeySearchEngine)
	if err != nil || searchEngine == "" {
		searchEngine = models.SearchEngineGoogle
	}

	// 记录搜索日志
	ip := c.ClientIP()
	ua := c.Request.UserAgent()
	referer := c.Request.Referer()
	go func() {
		_ = models.CreateAccessLog(ip, ua, models.ActionTypeSearch, query, referer)
	}()

	// 重定向到搜索引擎
	targetURL := fmt.Sprintf(searchEngine, query)
	c.Redirect(http.StatusFound, targetURL)
}

// LoginGet renders the admin login page.
func LoginGet(c *gin.Context) {
	// If already logged in, redirect to admin dashboard
	if sessionID, err := c.Cookie("session_id"); err == nil && sessionID != "" {
		store := c.MustGet("sessionStore").(*session.SessionStore)
		if store.Get(sessionID) != nil {
			c.Redirect(http.StatusFound, "/admin")
			return
		}
	}

	c.HTML(http.StatusOK, "admin/login.html", gin.H{
		"Title": "登录",
		"Error": "",
	})
}

// LoginPost handles the login form submission.
// It includes login logging, IP ban checking, and automatic IP banning on repeated failures.
func LoginPost(c *gin.Context) {
	username := c.PostForm("username")
	password := c.PostForm("password")
	clientIP := c.ClientIP()
	userAgent := c.Request.UserAgent()

	if username == "" || password == "" {
		_ = models.CreateLoginLog(nil, username, clientIP, userAgent, false)
		c.HTML(http.StatusOK, "admin/login.html", gin.H{
			"Title": "登录",
			"Error": "请输入用户名和密码",
		})
		return
	}

	// Check if IP is whitelisted — whitelist IPs bypass all ban checks
	isWhitelisted, _ := models.IsIPWhitelisted(clientIP)

	// Check if IP is currently banned (skip for whitelisted IPs)
	if !isWhitelisted {
		banned, ban, _ := models.IsIPBanned(clientIP)
		if banned && ban != nil {
			_ = models.CreateLoginLog(nil, username, clientIP, userAgent, false)
			c.HTML(http.StatusOK, "admin/login.html", gin.H{
				"Title": "登录",
				"Error": fmt.Sprintf("您的IP已被封禁，解封时间：%s", ban.BannedUntil.Format("2006-01-02 15:04:05")),
			})
			return
		}
	}

	matched, admin, err := models.VerifyPassword(username, password)
	if err != nil {
		_ = models.CreateLoginLog(nil, username, clientIP, userAgent, false)
		c.HTML(http.StatusOK, "admin/login.html", gin.H{
			"Title": "登录",
			"Error": "登录失败，请重试",
		})
		return
	}

	if !matched || admin == nil {
		_ = models.CreateLoginLog(nil, username, clientIP, userAgent, false)

		// Record failure in IPBanGuard (skip for whitelisted IPs)
		if !isWhitelisted {
			guard := c.MustGet("ipBanGuard").(*middleware.IPBanGuard)
			if guard.RecordFail(clientIP) {
				// Auto-ban this IP for 30 minutes
				_ = models.CreateIPBan(clientIP, "登录失败次数过多（自动封禁）", 5, time.Now().Add(30*time.Minute))
			}
		}

		c.HTML(http.StatusOK, "admin/login.html", gin.H{
			"Title": "登录",
			"Error": "用户名或密码错误",
		})
		return
	}

	// Successful login
	adminID := admin.ID
	_ = models.CreateLoginLog(&adminID, username, clientIP, userAgent, true)

	// Reset fail counter for this IP on successful login
	if !isWhitelisted {
		guard := c.MustGet("ipBanGuard").(*middleware.IPBanGuard)
		guard.ResetFail(clientIP)
	}

	// Create session
	store := c.MustGet("sessionStore").(*session.SessionStore)
	sessionID := store.Create(admin.ID, admin.Username)

	// Set cookie
	c.SetCookie("session_id", sessionID, 86400, "/", "", false, true)
	c.Redirect(http.StatusFound, "/admin")
}

// Logout handles logging out the current admin.
func Logout(c *gin.Context) {
	sessionID, _ := c.Cookie("session_id")
	if sessionID != "" {
		store := c.MustGet("sessionStore").(*session.SessionStore)
		store.Delete(sessionID)
	}

	// Clear cookie
	c.SetCookie("session_id", "", -1, "/", "", false, true)
	c.Redirect(http.StatusFound, "/admin/login")
}

// AdminIndex renders the admin dashboard.
// 包含访问统计数据和实时流量信息。
func AdminIndex(c *gin.Context) {
	username, _ := c.Get("username")

	// 获取访问统计
	stats, err := models.GetAccessLogStats()
	if err != nil {
		stats = &models.AccessLogStats{}
	}

	// 获取最近访问记录（20条）
	recentLogs, err := models.GetRecentAccessLogs(20)
	if err != nil {
		recentLogs = []models.AccessLog{}
	}

	// 获取IP统计（Top 10）
	ipStats, err := models.GetAccessLogStatsByIP(10)
	if err != nil {
		ipStats = nil
	}

	c.HTML(http.StatusOK, "admin/index.html", gin.H{
		"Title":      "管理后台",
		"Username":   username,
		"Stats":      stats,
		"RecentLogs": recentLogs,
		"IPStats":    ipStats,
	})
}