package main

import (
	"strconv"
	"strings"

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

func (a *App) audit(operator uint, action, targetType, targetID, metadata string) {
	_ = a.db.Create(&AuditLog{OperatorID: operator, Action: action, TargetType: targetType, TargetID: targetID, Metadata: metadata}).Error
}

func defaultPermissions(role string) []string {
	if role == RolePrivileged {
		return []string{PermDownload, PermRedeem, PermWebDAV, PermWebDAVConfig}
	}
	if role == RoleUser {
		return []string{PermDownload, PermRedeem}
	}
	return nil
}

func (a *App) adminListUsers(c *gin.Context) {
	var users []User
	if err := a.db.Order("id asc").Find(&users).Error; err != nil {
		c.JSON(500, gin.H{"error": err.Error()})
		return
	}
	for i := range users {
		users[i].PasswordHash = ""
	}
	c.JSON(200, gin.H{"data": users})
}

func (a *App) adminCreateUser(c *gin.Context) {
	var in struct {
		Username string `json:"username"`
		Password string `json:"password"`
		Role     string `json:"role"`
		Credits  int64  `json:"credits"`
	}
	if c.BindJSON(&in) != nil || strings.TrimSpace(in.Username) == "" || len(in.Password) < 8 {
		c.JSON(400, gin.H{"error": "username and password(8+) required"})
		return
	}
	if in.Role == "" {
		in.Role = RoleUser
	}
	if in.Role != RoleUser && in.Role != RolePrivileged && in.Role != RoleAdmin {
		c.JSON(400, gin.H{"error": "invalid role"})
		return
	}
	hash, err := hashPassword(in.Password)
	if err != nil {
		c.JSON(500, gin.H{"error": err.Error()})
		return
	}
	var u User
	err = a.db.Transaction(func(tx *gorm.DB) error {
		u = User{Username: strings.TrimSpace(in.Username), PasswordHash: hash, Role: in.Role, Status: UserActive}
		if err := tx.Create(&u).Error; err != nil {
			return err
		}
		if err := tx.Create(&CreditAccount{UserID: u.ID, Balance: in.Credits}).Error; err != nil {
			return err
		}
		for _, p := range defaultPermissions(in.Role) {
			if err := tx.Create(&UserPermission{UserID: u.ID, Permission: p, Enabled: true}).Error; err != nil {
				return err
			}
		}
		if in.Credits > 0 {
			if err := tx.Create(&CreditTransaction{UserID: u.ID, Type: "grant", Amount: in.Credits, BalanceAfter: in.Credits, ReferenceType: "admin", ReferenceID: strconv.FormatUint(uint64(c.MustGet("user").(*User).ID), 10), Reason: "initial credits"}).Error; err != nil {
				return err
			}
		}
		return nil
	})
	if err != nil {
		c.JSON(400, gin.H{"error": err.Error()})
		return
	}
	u.PasswordHash = ""
	c.JSON(201, u)
}

func (a *App) adminAudit(c *gin.Context) {
	var logs []AuditLog
	q := a.db.Order("id desc").Limit(200)
	if action := c.Query("action"); action != "" {
		q = q.Where("action = ?", action)
	}
	if err := q.Find(&logs).Error; err != nil {
		c.JSON(500, gin.H{"error": err.Error()})
		return
	}
	c.JSON(200, gin.H{"data": logs})
}

func (a *App) adminUpdateUser(c *gin.Context) {
	id, err := strconv.ParseUint(c.Param("id"), 10, 64)
	if err != nil {
		c.Status(400)
		return
	}
	var in struct {
		Password *string `json:"password"`
		Role     *string `json:"role"`
		Status   *string `json:"status"`
	}
	if c.BindJSON(&in) != nil {
		c.Status(400)
		return
	}
	var u User
	if a.db.First(&u, id).Error != nil {
		c.Status(404)
		return
	}
	if in.Password != nil {
		if len(*in.Password) < 8 {
			c.JSON(400, gin.H{"error": "password must be 8+"})
			return
		}
		h, e := hashPassword(*in.Password)
		if e != nil {
			c.JSON(500, gin.H{"error": e.Error()})
			return
		}
		u.PasswordHash = h
	}
	if in.Role != nil {
		if *in.Role != RoleUser && *in.Role != RolePrivileged && *in.Role != RoleAdmin {
			c.JSON(400, gin.H{"error": "invalid role"})
			return
		}
		u.Role = *in.Role
	}
	if in.Status != nil {
		if *in.Status != UserActive && *in.Status != UserDisabled {
			c.JSON(400, gin.H{"error": "invalid status"})
			return
		}
		u.Status = *in.Status
	}
	if err := a.db.Save(&u).Error; err != nil {
		c.JSON(500, gin.H{"error": err.Error()})
		return
	}
	u.PasswordHash = ""
	c.JSON(200, u)
}