//! Wire types shared between `hive-c0re` and the in-container harness.

use serde::{Deserialize, Serialize};

// -----------------------------------------------------------------------------
// Host admin socket — /run/hyperhive/host.sock
// -----------------------------------------------------------------------------

/// Requests on the host admin socket.
///
/// Wire format: one JSON object per line.
#[derive(Debug, Clone, Serialize, Deserialize)]
#[serde(tag = "cmd", rename_all = "snake_case")]
pub enum HostRequest {
    /// Create and start a sub-agent container `hive-agent-<name>`.
    Spawn { name: String },
    /// Stop a managed container (graceful).
    Kill { name: String },
    /// Apply pending config to a managed container.
    Rebuild { name: String },
    /// List managed containers.
    List,
    /// List pending approval requests.
    Pending,
    /// Approve a pending request by id; the action runs immediately.
    Approve { id: i64 },
    /// Deny a pending request by id.
    Deny { id: i64 },
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct HostResponse {
    pub ok: bool,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub error: Option<String>,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub agents: Option<Vec<String>>,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub approvals: Option<Vec<Approval>>,
}

#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Approval {
    pub id: i64,
    pub agent: String,
    pub commit_ref: String,
    pub requested_at: i64,
    pub status: ApprovalStatus,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub resolved_at: Option<i64>,
    #[serde(default, skip_serializing_if = "Option::is_none")]
    pub note: Option<String>,
}

#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
#[serde(rename_all = "snake_case")]
pub enum ApprovalStatus {
    Pending,
    Approved,
    Denied,
    Failed,
}

impl HostResponse {
    pub fn success() -> Self {
        Self {
            ok: true,
            error: None,
            agents: None,
            approvals: None,
        }
    }

    pub fn error(message: impl Into<String>) -> Self {
        Self {
            ok: false,
            error: Some(message.into()),
            agents: None,
            approvals: None,
        }
    }

    pub fn list(agents: Vec<String>) -> Self {
        Self {
            ok: true,
            error: None,
            agents: Some(agents),
            approvals: None,
        }
    }

    pub fn pending(approvals: Vec<Approval>) -> Self {
        Self {
            ok: true,
            error: None,
            agents: None,
            approvals: Some(approvals),
        }
    }
}

// -----------------------------------------------------------------------------
// Per-agent socket — /run/hyperhive/agents/<name>/mcp.sock on the host,
// bind-mounted into the container at /run/hive/mcp.sock.
// -----------------------------------------------------------------------------

/// A logical message between agents.
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct Message {
    pub from: String,
    pub to: String,
    pub body: String,
}

/// Requests on a per-agent socket. The agent's identity is the socket
/// it came in on; `Send.from` is filled in by the server, not the client.
#[derive(Debug, Clone, Serialize, Deserialize)]
#[serde(tag = "cmd", rename_all = "snake_case")]
pub enum AgentRequest {
    /// Send a message to another agent.
    Send { to: String, body: String },
    /// Pop one pending message from this agent's inbox.
    Recv,
}

/// Responses on a per-agent socket.
#[derive(Debug, Clone, Serialize, Deserialize)]
#[serde(tag = "kind", rename_all = "snake_case")]
pub enum AgentResponse {
    /// `Send` succeeded.
    Ok,
    /// Either `Send` failed or `Recv` errored.
    Err { message: String },
    /// `Recv` produced a message.
    Message { from: String, body: String },
    /// `Recv` found nothing pending.
    Empty,
}

// -----------------------------------------------------------------------------
// Manager socket — /run/hyperhive/manager/mcp.sock on the host, bind-mounted
// into the manager container at /run/hive/mcp.sock.
// -----------------------------------------------------------------------------

/// Logical name the broker uses for the manager.
pub const MANAGER_AGENT: &str = "manager";

/// Sender hive-c0re uses for events it pushes into the manager's inbox.
/// Manager harness recognises this and parses the body as a `HelperEvent`.
pub const SYSTEM_SENDER: &str = "system";

/// Out-of-band events the host-side daemon pushes to the manager's inbox.
/// Serialised as JSON in `Message::body` (sender = `SYSTEM_SENDER`).
#[derive(Debug, Clone, Serialize, Deserialize)]
#[serde(tag = "event", rename_all = "snake_case")]
pub enum HelperEvent {
    /// An approval was approved or denied; if approved, the rebuild has
    /// already run (status = Approved on success, Failed on error).
    ApprovalResolved {
        id: i64,
        agent: String,
        commit_ref: String,
        status: ApprovalStatus,
        #[serde(default, skip_serializing_if = "Option::is_none")]
        note: Option<String>,
    },
}

/// Requests on the manager socket. Manager has the agent surface (send/recv)
/// plus privileged lifecycle verbs.
#[derive(Debug, Clone, Serialize, Deserialize)]
#[serde(tag = "cmd", rename_all = "snake_case")]
pub enum ManagerRequest {
    Send {
        to: String,
        body: String,
    },
    Recv,
    /// Spawn a sub-agent. Phase 5 will gate this on user approval.
    Spawn {
        name: String,
    },
    /// Stop a sub-agent (graceful).
    Kill {
        name: String,
    },
    /// Submit a config commit for the user to approve. `commit_ref` is opaque
    /// to the host (typically a git sha pointing into the agent's config repo).
    /// On approval the host applies the change via `nixos-container update`.
    RequestApplyCommit {
        agent: String,
        commit_ref: String,
    },
}

#[derive(Debug, Clone, Serialize, Deserialize)]
#[serde(tag = "kind", rename_all = "snake_case")]
pub enum ManagerResponse {
    Ok,
    Err { message: String },
    Message { from: String, body: String },
    Empty,
}