merkle

type Bucket struct {
	// Type identifies the kind of content (e.g., "message")
	Type string `json:"type"`

	// Role indicates who produced this message ("system", "user", "assistant", "tool")
	Role string `json:"role"`

	// Content holds the message content blocks
	Content []llm.ContentBlock `json:"content"`

	// Model identifies the LLM model (e.g., "gpt-4", "claude-3-sonnet")
	Model string `json:"model"`

	// Provider identifies the API provider (e.g., "openai", "anthropic", "ollama")
	Provider string `json:"provider"`

	// AgentName identifies the agent harness (e.g., "claude", "opencode", "codex")
	AgentName string `json:"agent_name,omitempty"`
}

type Dag struct {
	// Root is the single root node of this directed graph
	Root *DagNode
	// contains filtered or unexported fields
}

type DagLoader interface {
	// Get retrieves a node by its hash.
	Get(ctx context.Context, hash string) (*Node, error)

	// GetByParent retrieves all nodes that have the given parent hash.
	// Pass nil to get root nodes.
	GetByParent(ctx context.Context, parentHash *string) ([]*Node, error)

	// Ancestry returns the path from a node back to its root (node first, root last).
	Ancestry(ctx context.Context, hash string) ([]*Node, error)
}

type DagNode struct {
	*Node

	// Parent is the parent node in the DAG (nil for root)
	Parent *DagNode

	// Children are the child nodes (empty for leaves)
	Children []*DagNode
}

type Node struct {
	// Hash is the content-addressed identifier (SHA-256, hex-encoded)
	Hash string `json:"hash"`

	// ParentHash links to the previous node hash.
	// This will be nil for root nodes.
	ParentHash *string `json:"parent_hash"`

	// Bucket is the hashable content for the node.
	Bucket Bucket `json:"bucket"`

	// StopReason indicates why generation stopped (only for responses)
	// Values: "stop", "length", "tool_use", "end_turn", etc.
	StopReason string `json:"stop_reason,omitempty"`

	// Usage contains token counts and timing (only for responses)
	Usage *llm.Usage `json:"usage,omitempty"`

	// Project is the git repository or project name that produced this node
	Project string `json:"project,omitempty"`
}

type NodeMeta struct {
	StopReason string
	Usage      *llm.Usage
	Project    string
}