#pragma once

/**
 * AutoForge DAG Engine
 *
 * Minimal skeleton for Phase 1.
 * Full task scheduling will be implemented in Phase 2.
 */

#include <string>
#include <vector>
#include <unordered_map>
#include <functional>
#include <mutex>

namespace autoforge {

/// Represents a single node in the execution DAG.
struct DAGNode {
    std::string id;
    std::string name;
    std::string type;               // e.g., "plan", "code", "test", "analyze"
    std::vector<std::string> deps;  // IDs of dependency nodes
};

/// DAG execution engine — schedules and runs task nodes.
class DAGEngine {
public:
    DAGEngine();
    ~DAGEngine();

    /// Get the engine version string.
    static std::string version();

    /// Add a node to the DAG.
    void add_node(const DAGNode& node);

    /// Get the number of nodes in the DAG.
    size_t node_count() const;

    /// Clear all nodes.
    void clear();

    /// Validate that the DAG has no cycles. Returns true if valid.
    bool validate() const;

    /// Execute the DAG (Phase 2 — currently a no-op).
    /// Returns true on success.
    bool execute();

private:
    std::vector<DAGNode> nodes_;
    std::unordered_map<std::string, size_t> index_;
    mutable std::mutex mutex_;
};

} // namespace autoforge