package api

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

	"github.com/gin-gonic/gin"
	"github.com/openteam/server/internal/pkg/resp"
	"github.com/openteam/server/internal/store"
	"gorm.io/gorm"
)

// AdminUsers GET /api/v1/admin/users — 用户列表（搜索、分页）。
func (h *Handler) AdminUsers(c *gin.Context) {
	page, _ := strconv.Atoi(c.DefaultQuery("page", "1"))
	size, _ := strconv.Atoi(c.DefaultQuery("page_size", "20"))
	if page < 1 {
		page = 1
	}
	if size < 1 || size > 100 {
		size = 20
	}
	q := h.a.DB.Model(&store.User{})
	if kw := c.Query("q"); kw != "" {
		q = q.Where("username LIKE ? OR email LIKE ?", "%"+kw+"%", "%"+kw+"%")
	}
	var total int64
	q.Count(&total)
	var users []store.User
	q.Order("id DESC").Offset((page - 1) * size).Limit(size).Find(&users)
	out := make([]gin.H, 0, len(users))
	for _, u := range users {
		out = append(out, h.publicUser(&u))
	}
	resp.OK(c, gin.H{"items": out, "total": total, "page": page, "page_size": size})
}

// AdminPatchUser PATCH /api/v1/admin/users/:id — 角色/状态/余额。
func (h *Handler) AdminPatchUser(c *gin.Context) {
	id, err := strconv.ParseUint(c.Param("id"), 10, 64)
	if err != nil {
		resp.Fail(c, http.StatusBadRequest, "invalid user id")
		return
	}
	var req struct {
		Role   *string `json:"role"`
		Status *string `json:"status"`
	}
	if err := c.ShouldBindJSON(&req); err != nil {
		resp.Fail(c, http.StatusBadRequest, "invalid input")
		return
	}
	var u store.User
	if err := h.a.DB.First(&u, id).Error; err != nil {
		resp.Fail(c, http.StatusNotFound, "user not found")
		return
	}
	updates := map[string]any{}
	if req.Role != nil {
		if *req.Role != store.RoleUser && *req.Role != store.RoleAdmin {
			resp.Fail(c, http.StatusBadRequest, "role must be user or admin")
			return
		}
		updates["role"] = *req.Role
	}
	if req.Status != nil {
		if *req.Status != store.UserStatusActive && *req.Status != store.UserStatusDisabled {
			resp.Fail(c, http.StatusBadRequest, "status must be active or disabled")
			return
		}
		updates["status"] = *req.Status
	}
	if len(updates) > 0 {
		h.a.DB.Model(&u).Updates(updates)
	}
	resp.OK(c, gin.H{"ok": true})
}

// AdminAdjustBalance POST /api/v1/admin/users/:id/balance — 调整余额并写流水。
func (h *Handler) AdminAdjustBalance(c *gin.Context) {
	admin, _ := userFromContext(c)
	id, err := strconv.ParseUint(c.Param("id"), 10, 64)
	if err != nil {
		resp.Fail(c, http.StatusBadRequest, "invalid user id")
		return
	}
	var req struct {
		Change float64 `json:"change" binding:"required"`
		Remark string  `json:"remark"`
	}
	if err := c.ShouldBindJSON(&req); err != nil {
		resp.Fail(c, http.StatusBadRequest, "invalid input: change is required")
		return
	}
	var u store.User
	if err := h.a.DB.First(&u, id).Error; err != nil {
		resp.Fail(c, http.StatusNotFound, "user not found")
		return
	}
	newBalance := u.Balance + req.Change
	ref := fmt.Sprintf("admin:%d:%d", admin.ID, time.Now().UnixNano())
	err = h.a.DB.Transaction(func(tx *gorm.DB) error {
		if err := tx.Model(&store.User{}).Where("id = ?", u.ID).Update("balance", newBalance).Error; err != nil {
			return err
		}
		return tx.Create(&store.BalanceLog{
			UserID:       u.ID,
			Change:       req.Change,
			BalanceAfter: newBalance,
			Type:         store.BalanceTypeAdminAdjust,
			RefID:        ref,
			Remark:       req.Remark,
		}).Error
	})
	if err != nil {
		resp.Fail(c, http.StatusInternalServerError, "failed to adjust balance")
		return
	}
	resp.OK(c, gin.H{"ok": true, "balance": newBalance})
}

// AdminConfig GET /api/v1/admin/config
func (h *Handler) AdminConfig(c *gin.Context) {
	var cfgs []store.SystemConfig
	h.a.DB.Find(&cfgs)
	m := map[string]any{}
	for _, cfg := range cfgs {
		var v any
		_ = json.Unmarshal([]byte(cfg.Value), &v)
		m[cfg.Key] = v
	}
	m["registration.mode"] = h.a.Cfg.Auth.RegistrationMode
	resp.OK(c, gin.H{"config": m})
}

// AdminPutConfig PUT /api/v1/admin/config
func (h *Handler) AdminPutConfig(c *gin.Context) {
	var req struct {
		Config map[string]any `json:"config"`
	}
	if err := c.ShouldBindJSON(&req); err != nil {
		resp.Fail(c, http.StatusBadRequest, "invalid input")
		return
	}
	for k, v := range req.Config {
		if k == "registration.mode" {
			if v == "open" || v == "invite" {
				h.a.Cfg.Auth.RegistrationMode = v.(string)
			}
			continue
		}
		b, _ := json.Marshal(v)
		cfg := store.SystemConfig{Key: k, Value: string(b)}
		h.a.DB.Save(&cfg)
	}
	resp.OK(c, gin.H{"ok": true})
}