package api

import (
	"time"

	"github.com/gin-gonic/gin"

	"eaisalestrain/backend/internal/middleware"
	"eaisalestrain/backend/internal/model"
	"eaisalestrain/backend/internal/store"
	"eaisalestrain/backend/internal/web"
)

var validItemTypes = map[string]bool{"company": true, "product": true, "course": true}

// RecordLearningProgress POST /api/learning/progress —— 员工浏览内容时上报进度
func RecordLearningProgress(c *gin.Context) {
	u := middleware.CurrentUser(c)
	if u == nil {
		web.Fail(c, web.NewAuthError("未登录"))
		return
	}
	var req struct {
		ItemType string `json:"item_type"`
		ItemID   uint   `json:"item_id"`
	}
	if err := c.ShouldBindJSON(&req); err != nil || !validItemTypes[req.ItemType] {
		web.Fail(c, web.NewBadRequest("item_type 必填且合法（company/product/course）"))
		return
	}
	if req.ItemType == "company" {
		req.ItemID = 0
	}
	lp := model.LearningProgress{UserID: u.ID, ItemType: req.ItemType, ItemID: req.ItemID}
	// 幂等：已存在则仅刷新 updated_at；首次记录才加分（避免重复刷分）
	var existing model.LearningProgress
	if err := store.DB.Where("user_id = ? AND item_type = ? AND item_id = ?", u.ID, req.ItemType, req.ItemID).
		First(&existing).Error; err != nil {
		if createErr := store.DB.Create(&lp).Error; createErr != nil {
			web.Fail(c, web.NewBadRequest("记录学习进度失败"))
			return
		}
		awardFirstView(u.ID, req.ItemType, req.ItemID)
	} else {
		store.DB.Model(&existing).Update("updated_at", time.Now())
	}
	web.OK(c, gin.H{"recorded": true, "item_type": req.ItemType, "item_id": req.ItemID})
}

// MyLearningProgress GET /api/learning/me —— 我的学习进度
func MyLearningProgress(c *gin.Context) {
	u := middleware.CurrentUser(c)
	if u == nil {
		web.Fail(c, web.NewAuthError("未登录"))
		return
	}
	var items []model.LearningProgress
	store.DB.Where("user_id = ?", u.ID).Order("updated_at DESC").Find(&items)
	web.OK(c, items)
}

// AdminLearningProgress GET /api/system/learning-progress —— 全员学习进度（管理员）
func AdminLearningProgress(c *gin.Context) {
	var employees []model.User
	store.DB.Where("role = ?", "employee").Order("id ASC").Find(&employees)

	var items []model.LearningProgress
	store.DB.Order("updated_at DESC").Find(&items)

	type agg struct {
		CompanyViewed bool       `json:"company_viewed"`
		ProductCount  int        `json:"product_count"`
		CourseCount   int        `json:"course_count"`
		TotalItems    int        `json:"total_items"`
		LastViewedAt  *time.Time `json:"last_viewed_at"`
	}
	perUser := map[uint]*agg{}
	for _, lp := range items {
		a := perUser[lp.UserID]
		if a == nil {
			a = &agg{}
			perUser[lp.UserID] = a
		}
		switch lp.ItemType {
		case "company":
			a.CompanyViewed = true
		case "product":
			a.ProductCount++
		case "course":
			a.CourseCount++
		}
		a.TotalItems++
		if a.LastViewedAt == nil || lp.UpdatedAt.After(*a.LastViewedAt) {
			t := lp.UpdatedAt
			a.LastViewedAt = &t
		}
	}

	out := make([]gin.H, 0, len(employees))
	for _, e := range employees {
		a := perUser[e.ID]
		if a == nil {
			a = &agg{}
		}
		out = append(out, gin.H{
			"user_id": e.ID, "username": e.Username, "full_name": e.FullName,
			"department": e.Department, "position": e.Position,
			"company_viewed": a.CompanyViewed, "product_count": a.ProductCount,
			"course_count": a.CourseCount, "total_items": a.TotalItems,
			"last_viewed_at": a.LastViewedAt,
		})
	}
	web.OK(c, gin.H{"users": out})
}