model

type Adapter interface {
	// Stream sends a request and returns a channel of Chunks.
	// The implementation MUST close the channel after the stream ends or errors.
	// The implementation MUST respect context cancellation.
	Stream(ctx context.Context, req Request) (<-chan Chunk, error)

	// Name returns a human-readable identifier for this adapter,
	// e.g. "openai", "anthropic", "gemini".
	Name() string
}

type Chunk struct {
	Type             ChunkType      `json:"type"`
	Text             string         `json:"text,omitempty"`
	ReasoningContent string         `json:"reasoning_content,omitempty"`
	ToolCall         *ToolCallDelta `json:"tool_call,omitempty"`
	Finish           *FinishReason  `json:"finish,omitempty"`
	Usage            *Usage         `json:"usage,omitempty"`
	Err              error          `json:"-"`
}

type ChunkType string

type FinishReason struct {
	Reason string `json:"reason"`
}

type Message struct {
	Role       MessageRole `json:"role"`
	Content    string      `json:"content"`
	ToolCallID string      `json:"tool_call_id,omitempty"`
	ToolCalls  []ToolCall  `json:"tool_calls,omitempty"`
}

type MessageRole string

type Request struct {
	Model     string    `json:"model"`
	Messages  []Message `json:"messages"`
	Tools     []ToolDef `json:"tools,omitempty"`
	Stream    bool      `json:"stream"`
	MaxTokens int       `json:"max_tokens,omitempty"`
}

type ToolCall struct {
	ID        string          `json:"id"`
	Name      string          `json:"name"`
	Arguments json.RawMessage `json:"arguments"`
}

type ToolCallDelta struct {
	ID        string          `json:"id,omitempty"`
	Index     int             `json:"index"`
	Name      string          `json:"name,omitempty"`
	Arguments json.RawMessage `json:"arguments,omitempty"`
}

type ToolDef struct {
	Name        string          `json:"name"`
	Description string          `json:"description"`
	InputSchema json.RawMessage `json:"input_schema"`
}

type Usage struct {
	InputTokens  int `json:"input_tokens,omitempty"`
	OutputTokens int `json:"output_tokens,omitempty"`
}