core

type BaseTool struct {
	*responses.ToolUnion
	RequiresApproval bool
}

type ChatHistory interface {
	// AddMessages adds new messages into a list in-memory
	AddMessages(ctx context.Context, messages []responses.InputMessageUnion, usage *responses.Usage)

	// GetMessages returns a list of messages from in-memory. It handles summarization if enabled
	GetMessages(ctx context.Context) ([]responses.InputMessageUnion, error)

	// LoadMessages fetches all the messages of the thread from persistent storage into memory
	LoadMessages(ctx context.Context, namespace string, previousMessageID string) ([]responses.InputMessageUnion, error)

	// SaveMessages saves the messages to persistent storage
	SaveMessages(ctx context.Context, meta map[string]any) error

	// GetMeta returns the meta from the most recent message
	GetMeta() map[string]any

	// GetMessageID returns the current run id
	GetMessageID() string
}

type DurableExecutor interface {
	// Run executes a function with durability guarantees.
	// If the process crashes after fn() completes, the result is restored
	// from the checkpoint instead of re-executing fn().
	//
	// The name parameter is used to identify the checkpoint (must be unique per step).
	Run(ctx context.Context, name string, fn func(ctx context.Context) (any, error)) (any, error)

	// Set stores a value in durable state.
	// The value persists across crashes and can be retrieved with Get().
	Set(ctx context.Context, key string, value any) error

	// Get retrieves a value from durable state.
	// Returns the value and true if found, or nil and false if not found.
	Get(ctx context.Context, key string) (any, bool, error)

	// Checkpoint creates an explicit checkpoint marker.
	// Useful for marking progress without storing data.
	Checkpoint(ctx context.Context, name string) error
}

type HistorySummarizer interface {
	// Summarize takes a list of messages and returns a summary result.
	// If summarization is not needed, returns a result with KeepFromIndex = -1.
	Summarize(ctx context.Context, msgIdToRunId map[string]string, messages []responses.InputMessageUnion, usage *responses.Usage) (*SummaryResult, error)
}

type NoOpExecutor struct{}

type RunState struct {
	CurrentStep           Step                            `json:"current_step"`
	LoopIteration         int                             `json:"loop_iteration"`
	Usage                 responses.Usage                 `json:"usage"`
	PendingToolCalls      []responses.FunctionCallMessage `json:"pending_tool_calls,omitempty"`
	ToolsAwaitingApproval []responses.FunctionCallMessage `json:"tools_awaiting_approval,omitempty"`
}

type RunStatus string

type Step string

type SummaryResult struct {
	Summary                 *responses.InputMessageUnion // The summary message
	MessagesToKeep          []responses.InputMessageUnion
	LastSummarizedMessageID string // ID of the last message that was summarized
	SummaryID               string // Unique ID for the summary (generated if empty)
}

type SystemPromptProvider interface {
	GetPrompt(ctx context.Context, data map[string]any) (string, error)
}

type Tool interface {
	Execute(ctx context.Context, params *responses.FunctionCallMessage) (*responses.FunctionCallOutputMessage, error)
	Tool(ctx context.Context) *responses.ToolUnion
	NeedApproval() bool
}