Added membership for users

models/plans.go

@@ -1,9 +1,12 @@
 package models
 
 import (
+	"crypto/rand"
+	"encoding/base64"
 	"errors"
-	"gorm.io/gorm"
 	. "planner/errors"
+
+	"gorm.io/gorm"
 )
 
 func GetPlan(orm *gorm.DB, user User, id uint) (*Plan, error) {
@@ -48,3 +51,80 @@ func (p *Plan) IsMember(orm *gorm.DB, u *User) (bool, error) {
 	}
 	return member_count == 1, nil
 }
+
+func (p *Plan) GetMember(orm *gorm.DB, u *User) (*Member, error) {
+	var m Member
+	result := orm.
+		Table("members").
+		Where("user_id=? AND plan_id=?", u.Username, p.ID).
+		Take(&m).Error
+	if result != nil {
+		return nil, ErrNotMember
+	}
+	return &m, nil
+}
+
+func (p *Plan) HasNonUser(orm *gorm.DB, name string) (bool, error) {
+	var member_count int64
+	result := orm.
+		Table("members").
+		Where("plan_id=? AND name=?", p.ID, name).
+		Count(&member_count).Error
+	if result != nil {
+		return false, result
+	}
+	return member_count == 1, nil
+}
+
+func (p *Plan) AddMember(orm *gorm.DB, new_member *Member) error {
+	if new_member == nil {
+		return errors.New("Member is nil")
+	}
+	new_member.PlanID = p.ID
+	if new_member.Type == "non-user" {
+		found, err := p.HasNonUser(orm, new_member.Name)
+		if err != nil {
+			return nil
+		}
+		if found {
+			return errors.New("Non user name taken")
+		}
+		new_member.Status = "ready"
+		return orm.Create(&new_member).Error
+
+	} else if new_member.Type == "user" {
+		user, err := GetUser(orm, new_member.UserID)
+		if err != nil {
+			return err
+		}
+
+		found, err := p.IsMember(orm, &user)
+		if err != nil {
+			return nil
+		}
+		if found {
+			return errors.New("User already is member")
+		}
+
+		new_member.Status = "pending"
+		var res error
+		for retries := 3; retries >= 0; retries -= 1 {
+			join_code := make([]byte, 32)
+			_, err = rand.Read(join_code)
+			if err != nil {
+				return err
+			}
+			new_member.JoinCode = base64.URLEncoding.EncodeToString(join_code)
+			res = orm.Create(&new_member).Error
+
+			if res == nil {
+				break
+			} else if !errors.Is(res, gorm.ErrDuplicatedKey) {
+				return res
+			}
+		}
+		return res
+	} else {
+		return errors.New("Invalid type for user")
+	}
+}