package models

import (
	"time"

	"gorm.io/gorm"
)

// Conversation represents a chat conversation between users and/or agents
type Conversation struct {
	ID            uint           `json:"id" gorm:"primaryKey"`
	Title         string         `json:"title"`
	UserID        uint           `json:"userId"`
	AgentID       *uint          `json:"agentId,omitempty"`
	Status        string         `json:"status" gorm:"default:'active'"` // 'active', 'closed', 'escalated'
	Department    string         `json:"department"`
	Priority      string         `json:"priority" gorm:"default:'medium'"` // 'low', 'medium', 'high', 'urgent'
	Tags          string         `json:"tags"`                             // Comma-separated tags
	LastMessageAt time.Time      `json:"lastMessageAt"`
	CreatedAt     time.Time      `json:"createdAt"`
	UpdatedAt     time.Time      `json:"updatedAt"`
	DeletedAt     gorm.DeletedAt `json:"-" gorm:"index"`

	// Relationships
	User     User      `json:"user" gorm:"foreignKey:UserID"`
	Agent    *User     `json:"agent,omitempty" gorm:"foreignKey:AgentID"`
	Messages []Message `json:"messages" gorm:"foreignKey:ConversationID"`
}

// Message represents a single message in a conversation
type Message struct {
	ID             uint           `json:"id" gorm:"primaryKey"`
	ConversationID uint           `json:"conversationId"`
	UserID         uint           `json:"userId"`
	Content        string         `json:"content" gorm:"not null"`
	Type           string         `json:"type" gorm:"default:'text'"`   // 'text', 'image', 'file', 'system'
	Status         string         `json:"status" gorm:"default:'sent'"` // 'sent', 'delivered', 'read'
	Sentiment      float64        `json:"sentiment"`                    // Sentiment score from -1 (negative) to 1 (positive)
	IsAI           bool           `json:"isAI" gorm:"default:false"`
	AIModel        string         `json:"aiModel,omitempty"` // Which AI model generated this message
	ReadAt         *time.Time     `json:"readAt,omitempty"`
	CreatedAt      time.Time      `json:"createdAt"`
	UpdatedAt      time.Time      `json:"updatedAt"`
	DeletedAt      gorm.DeletedAt `json:"-" gorm:"index"`

	// Relationships
	Conversation Conversation `json:"conversation" gorm:"foreignKey:ConversationID"`
	User         User         `json:"user" gorm:"foreignKey:UserID"`
}


// BeforeCreate is a GORM hook that sets the LastMessageAt field when creating a conversation
func (c *Conversation) BeforeCreate(tx *gorm.DB) error {
	c.LastMessageAt = time.Now()
	return nil
}

// BeforeCreate is a GORM hook that updates the conversation's LastMessageAt when creating a message
func (m *Message) BeforeCreate(tx *gorm.DB) error {
	// Update the conversation's LastMessageAt
	tx.Model(&Conversation{}).Where("id = ?", m.ConversationID).Update("last_message_at", time.Now())
	return nil
}