package model

import (
	"encoding/json"
	"path/filepath"
	"strings"
)

// Attachment represents a file attachment on a message.
// Reference: Chatwoot Attachment model + P2B M3 spec
type Attachment struct {
	Base
	MessageID   uint   `gorm:"column:message_id;not null;index" json:"message_id"`
	AccountID   uint   `gorm:"column:account_id;not null;index" json:"account_id"`
	FileType    string `gorm:"column:file_type;size:50;not null" json:"file_type"` // image/audio/video/file/location/emoji/contact
	ExternalURL string `gorm:"column:external_url;size:512" json:"external_url"`
	FileURL     string `gorm:"column:file_url;size:512" json:"file_url"`
	ThumbURL    string `gorm:"column:thumb_url;size:512" json:"thumb_url"`
	FileSize    int    `gorm:"column:file_size" json:"file_size"`
	FileName    string `gorm:"column:file_name;size:255" json:"file_name"`
	Width       int    `gorm:"column:width" json:"width"`
	Height      int    `gorm:"column:height" json:"height"`
	AltText     string `gorm:"column:alt_text;size:255" json:"alt_text"`
	Metadata    string `gorm:"column:metadata;type:jsonb" json:"metadata"`

	Message Message `gorm:"foreignKey:MessageID" json:"message,omitempty"`
	Account Account `gorm:"foreignKey:AccountID" json:"account,omitempty"`
}

func (Attachment) TableName() string { return "attachments" }

// PushEventData matches Chatwoot's attachment payload shared by HTTP and WebSocket messages.
func (a *Attachment) PushEventData() map[string]any {
	dataURL := a.FileURL
	if dataURL == "" {
		dataURL = a.ExternalURL
	}
	payload := map[string]any{
		"id":         a.ID,
		"message_id": a.MessageID,
		"file_type":  a.FileType,
		"account_id": a.AccountID,
		"data_url":   dataURL,
		"thumb_url":  a.ThumbURL,
		"file_size":  a.FileSize,
		"extension":  strings.TrimPrefix(filepath.Ext(a.FileName), "."),
		"width":      a.Width,
		"height":     a.Height,
	}
	metadata := map[string]any{}
	if json.Unmarshal([]byte(a.Metadata), &metadata) == nil && len(metadata) > 0 {
		payload["metadata"] = metadata
	}
	return payload
}