package model

import (
	"errors"
	"strings"

	"gorm.io/gorm"
)

// Project represents a project in the system
type Project struct {
	BaseModel
	Name        string `json:"name" gorm:"not null;type:varchar(255)"`
	Description string `json:"description" gorm:"type:text"`
	OwnerID     string `json:"owner_id" gorm:"not null;type:uuid;index;references:users(id)"`
	TypeID      string `json:"type_id" gorm:"not null;type:uuid;index;references:types(id)"`
	Owner       User   `json:"owner,omitempty" gorm:"foreignKey:OwnerID"`
	Type        Type   `json:"type,omitempty" gorm:"foreignKey:TypeID"`
	Tasks       []Task `json:"tasks,omitempty" gorm:"foreignKey:ProjectID"`
	Members     []User `json:"members,omitempty" gorm:"many2many:project_members;"`
}

// ProjectCreateRequest represents the request to create a new project
type ProjectCreateRequest struct {
	Name        string `json:"name" validate:"required,min=1,max=255"`
	Description string `json:"description" validate:"max=1000"`
	OwnerID     string `json:"owner_id" validate:"required,uuid"`
	TypeID      string `json:"type_id" validate:"required,uuid"`
}

// ProjectUpdateRequest represents the request to update a project
type ProjectUpdateRequest struct {
	Name        *string `json:"name,omitempty" validate:"omitempty,min=1,max=255"`
	Description *string `json:"description,omitempty" validate:"omitempty,max=1000"`
	TypeID      *string `json:"type_id,omitempty" validate:"omitempty,uuid"`
}

// ProjectInfo represents public project information
type ProjectInfo struct {
	ID          string   `json:"id"`
	Name        string   `json:"name"`
	Description string   `json:"description"`
	OwnerID     string   `json:"owner_id"`
	TypeID      string   `json:"type_id"`
	Owner       UserInfo `json:"owner,omitempty"`
	Type        TypeInfo `json:"type,omitempty"`
	TaskCount   int64    `json:"task_count"`
	MemberCount int64    `json:"member_count"`
	CreatedAt   string   `json:"created_at"`
	UpdatedAt   string   `json:"updated_at"`
}

// ProjectMember represents the many-to-many relationship between projects and users
type ProjectMember struct {
	ProjectID string  `json:"project_id" gorm:"type:uuid;primaryKey"`
	UserID    string  `json:"user_id" gorm:"type:uuid;primaryKey"`
	RoleID    string  `json:"role_id" gorm:"type:uuid;not null;references:roles(id)"`
	Project   Project `json:"project,omitempty" gorm:"foreignKey:ProjectID"`
	User      User    `json:"user,omitempty" gorm:"foreignKey:UserID"`
	Role      Role    `json:"role,omitempty" gorm:"foreignKey:RoleID"`
}

// BeforeCreate is called before creating a project
func (p *Project) BeforeCreate(tx *gorm.DB) error {
	p.BaseModel.BeforeCreate()

	// Normalize name and description
	p.Name = strings.TrimSpace(p.Name)
	p.Description = strings.TrimSpace(p.Description)

	return p.Validate()
}

// BeforeUpdate is called before updating a project
func (p *Project) BeforeUpdate(tx *gorm.DB) error {
	p.BaseModel.BeforeUpdate()

	// Normalize fields if they're being updated
	if p.Name != "" {
		p.Name = strings.TrimSpace(p.Name)
	}
	if p.Description != "" {
		p.Description = strings.TrimSpace(p.Description)
	}

	return p.Validate()
}

// Validate validates project data
func (p *Project) Validate() error {
	if p.Name == "" {
		return errors.New("name is required")
	}

	if len(p.Name) > 255 {
		return errors.New("name must not exceed 255 characters")
	}

	if p.OwnerID == "" {
		return errors.New("owner_id is required")
	}

	if p.TypeID == "" {
		return errors.New("type_id is required")
	}

	return nil
}

// ToProjectInfo converts Project to ProjectInfo (public information)
func (p *Project) ToProjectInfo() ProjectInfo {
	projectInfo := ProjectInfo{
		ID:          p.ID,
		Name:        p.Name,
		Description: p.Description,
		OwnerID:     p.OwnerID,
		TypeID:      p.TypeID,
		CreatedAt:   p.CreatedAt.Format("2006-01-02T15:04:05Z07:00"),
		UpdatedAt:   p.UpdatedAt.Format("2006-01-02T15:04:05Z07:00"),
	}

	// Add owner info if loaded
	if p.Owner.ID != "" {
		projectInfo.Owner = p.Owner.ToUserInfo()
	}

	// Add type info if loaded
	if p.Type.ID != "" {
		projectInfo.Type = p.Type.ToTypeInfo()
	}

	return projectInfo
}

// HasMember checks if a user is a member of the project
func (p *Project) HasMember(userID string) bool {
	for _, member := range p.Members {
		if member.ID == userID {
			return true
		}
	}
	return false
}

// IsOwner checks if a user is the owner of the project
func (p *Project) IsOwner(userID string) bool {
	return p.OwnerID == userID
}