package llm

// Role represents who authored a message.
type Role string

const (
	RoleSystem    Role = "system"
	RoleUser      Role = "user"
	RoleAssistant Role = "assistant"
	RoleTool      Role = "tool"
)

// Image represents an image attachment.
type Image struct {
	// Provide exactly one of URL or Base64.
	URL         string // HTTP(S) URL
	Base64      string // Raw base64-encoded data
	ContentType string // MIME type (e.g., "image/png"), required for Base64
}

// Audio represents an audio attachment.
type Audio struct {
	// Provide exactly one of URL or Base64.
	URL         string // HTTP(S) URL to audio file
	Base64      string // Raw base64-encoded audio data
	ContentType string // MIME type (e.g., "audio/wav", "audio/mp3")
}

// Content represents message content with optional text, images, and audio.
type Content struct {
	Text   string
	Images []Image
	Audio  []Audio
}

// ToolCall represents a tool invocation requested by the assistant.
type ToolCall struct {
	ID        string
	Name      string
	Arguments string // raw JSON
}

// Message represents a single message in a conversation.
type Message struct {
	Role    Role
	Content Content

	// ToolCallID is set when Role == RoleTool, identifying which tool call this responds to.
	ToolCallID string

	// ToolCalls is set when the assistant requests tool invocations.
	ToolCalls []ToolCall
}

// UserMessage creates a user message with text content.
func UserMessage(text string) Message {
	return Message{Role: RoleUser, Content: Content{Text: text}}
}

// UserMessageWithImages creates a user message with text and images.
func UserMessageWithImages(text string, images ...Image) Message {
	return Message{Role: RoleUser, Content: Content{Text: text, Images: images}}
}

// UserMessageWithAudio creates a user message with text and audio attachments.
func UserMessageWithAudio(text string, audio ...Audio) Message {
	return Message{Role: RoleUser, Content: Content{Text: text, Audio: audio}}
}

// SystemMessage creates a system prompt message.
func SystemMessage(text string) Message {
	return Message{Role: RoleSystem, Content: Content{Text: text}}
}

// AssistantMessage creates an assistant message with text content.
func AssistantMessage(text string) Message {
	return Message{Role: RoleAssistant, Content: Content{Text: text}}
}

// ToolResultMessage creates a tool result message.
func ToolResultMessage(toolCallID string, result string) Message {
	return Message{
		Role:       RoleTool,
		Content:    Content{Text: result},
		ToolCallID: toolCallID,
	}
}