rpc_methods.hpp

// Copyright (c) 2025 Elias Bachaalany
// SPDX-License-Identifier: MIT

#pragma once

/// @file rpc_methods.hpp
/// @brief Catalog of JSON-RPC method names used by the Copilot CLI SDK.
///
/// Mirrors the canonical method-name surface generated by the upstream
/// nodejs reference at `nodejs/src/generated/rpc.ts`. Each constant is the
/// exact wire string the server expects. Use these symbols in `invoke()`,
/// `set_request_handler` dispatch, and tests instead of hard-coding strings,
/// so the catalog can be diffed against upstream when bumping versions.

#include <copilot/jsonrpc.hpp>
#include <functional>
#include <mutex>
#include <string>
#include <unordered_map>

namespace copilot::rpc::methods
{

// =============================================================================
// Top-level client API (no per-session scoping)
// =============================================================================

inline constexpr const char* kPing                  = "ping";
inline constexpr const char* kConnect               = "connect";
inline constexpr const char* kModelsList            = "models.list";
inline constexpr const char* kToolsList             = "tools.list";
inline constexpr const char* kAccountGetQuota       = "account.getQuota";

// MCP global config
inline constexpr const char* kMcpConfigList         = "mcp.config.list";
inline constexpr const char* kMcpConfigAdd          = "mcp.config.add";
inline constexpr const char* kMcpConfigUpdate       = "mcp.config.update";
inline constexpr const char* kMcpConfigRemove       = "mcp.config.remove";
inline constexpr const char* kMcpConfigEnable       = "mcp.config.enable";
inline constexpr const char* kMcpConfigDisable      = "mcp.config.disable";
inline constexpr const char* kMcpDiscover           = "mcp.discover";

// Skills global config
inline constexpr const char* kSkillsConfigSetDisabledSkills = "skills.config.setDisabledSkills";
inline constexpr const char* kSkillsDiscover                = "skills.discover";

// Session filesystem provider (client-side fs registration)
inline constexpr const char* kSessionFsSetProvider  = "sessionFs.setProvider";

// Session lifecycle (top-level)
inline constexpr const char* kSessionsFork          = "sessions.fork";
inline constexpr const char* kSessionsConnect       = "sessions.connect";

// =============================================================================
// Server-to-client requests (the runtime calls these on the SDK client)
// All take a `sessionId` to route to the registered handler set.
// =============================================================================

inline constexpr const char* kSessionFsReadFile           = "sessionFs.readFile";
inline constexpr const char* kSessionFsWriteFile          = "sessionFs.writeFile";
inline constexpr const char* kSessionFsAppendFile         = "sessionFs.appendFile";
inline constexpr const char* kSessionFsExists             = "sessionFs.exists";
inline constexpr const char* kSessionFsStat               = "sessionFs.stat";
inline constexpr const char* kSessionFsMkdir              = "sessionFs.mkdir";
inline constexpr const char* kSessionFsReaddir            = "sessionFs.readdir";
inline constexpr const char* kSessionFsReaddirWithTypes   = "sessionFs.readdirWithTypes";
inline constexpr const char* kSessionFsRm                 = "sessionFs.rm";
inline constexpr const char* kSessionFsRename             = "sessionFs.rename";

// =============================================================================
// Session-scoped methods (per-session API; each carries a `sessionId`)
// =============================================================================

inline constexpr const char* kSessionSuspend                                  = "session.suspend";
inline constexpr const char* kSessionLog                                      = "session.log";

inline constexpr const char* kSessionAuthGetStatus                            = "session.auth.getStatus";

inline constexpr const char* kSessionModelGetCurrent                          = "session.model.getCurrent";
inline constexpr const char* kSessionModelSwitchTo                            = "session.model.switchTo";
inline constexpr const char* kSessionModelSwitchAutoTier                      = "session.model.switchAutoTier";
inline constexpr const char* kManagedSettingsClearCache                       = "managedSettings.clearCache";

inline constexpr const char* kSessionModeGet                                  = "session.mode.get";
inline constexpr const char* kSessionModeSet                                  = "session.mode.set";

inline constexpr const char* kSessionNameGet                                  = "session.name.get";
inline constexpr const char* kSessionNameSet                                  = "session.name.set";

inline constexpr const char* kSessionPlanRead                                 = "session.plan.read";
inline constexpr const char* kSessionPlanUpdate                               = "session.plan.update";
inline constexpr const char* kSessionPlanDelete                               = "session.plan.delete";

inline constexpr const char* kSessionWorkspacesGetWorkspace                   = "session.workspaces.getWorkspace";
inline constexpr const char* kSessionWorkspacesListFiles                      = "session.workspaces.listFiles";
inline constexpr const char* kSessionWorkspacesReadFile                       = "session.workspaces.readFile";
inline constexpr const char* kSessionWorkspacesCreateFile                     = "session.workspaces.createFile";

inline constexpr const char* kSessionInstructionsGetSources                   = "session.instructions.getSources";

inline constexpr const char* kSessionFleetStart                               = "session.fleet.start";

inline constexpr const char* kSessionAgentList                                = "session.agent.list";
inline constexpr const char* kSessionAgentGetCurrent                          = "session.agent.getCurrent";
inline constexpr const char* kSessionAgentSelect                              = "session.agent.select";
inline constexpr const char* kSessionAgentDeselect                            = "session.agent.deselect";
inline constexpr const char* kSessionAgentReload                              = "session.agent.reload";

inline constexpr const char* kSessionTasksStartAgent                          = "session.tasks.startAgent";
inline constexpr const char* kSessionTasksList                                = "session.tasks.list";
inline constexpr const char* kSessionTasksPromoteToBackground                 = "session.tasks.promoteToBackground";
inline constexpr const char* kSessionTasksCancel                              = "session.tasks.cancel";
inline constexpr const char* kSessionTasksRemove                              = "session.tasks.remove";
inline constexpr const char* kSessionTasksSendMessage                         = "session.tasks.sendMessage";

inline constexpr const char* kSessionSkillsList                               = "session.skills.list";
inline constexpr const char* kSessionSkillsEnable                             = "session.skills.enable";
inline constexpr const char* kSessionSkillsDisable                            = "session.skills.disable";
inline constexpr const char* kSessionSkillsReload                             = "session.skills.reload";

inline constexpr const char* kSessionMcpList                                  = "session.mcp.list";
inline constexpr const char* kSessionMcpEnable                                = "session.mcp.enable";
inline constexpr const char* kSessionMcpDisable                               = "session.mcp.disable";
inline constexpr const char* kSessionMcpReload                                = "session.mcp.reload";
inline constexpr const char* kSessionMcpOauthLogin                            = "session.mcp.oauth.login";

inline constexpr const char* kSessionPluginsList                              = "session.plugins.list";

inline constexpr const char* kSessionExtensionsList                           = "session.extensions.list";
inline constexpr const char* kSessionExtensionsEnable                         = "session.extensions.enable";
inline constexpr const char* kSessionExtensionsDisable                        = "session.extensions.disable";
inline constexpr const char* kSessionExtensionsReload                         = "session.extensions.reload";

inline constexpr const char* kSessionToolsHandlePendingToolCall               = "session.tools.handlePendingToolCall";

inline constexpr const char* kSessionCommandsList                             = "session.commands.list";
inline constexpr const char* kSessionCommandsInvoke                           = "session.commands.invoke";
inline constexpr const char* kSessionCommandsHandlePendingCommand             = "session.commands.handlePendingCommand";
inline constexpr const char* kSessionCommandsRespondToQueuedCommand           = "session.commands.respondToQueuedCommand";

inline constexpr const char* kSessionUiElicitation                            = "session.ui.elicitation";
inline constexpr const char* kSessionUiHandlePendingElicitation               = "session.ui.handlePendingElicitation";

inline constexpr const char* kSessionPermissionsHandlePendingPermissionRequest = "session.permissions.handlePendingPermissionRequest";
inline constexpr const char* kSessionPermissionsSetApproveAll                  = "session.permissions.setApproveAll";
inline constexpr const char* kSessionPermissionsResetSessionApprovals          = "session.permissions.resetSessionApprovals";

inline constexpr const char* kSessionShellExec                                = "session.shell.exec";
inline constexpr const char* kSessionShellKill                                = "session.shell.kill";

inline constexpr const char* kSessionHistoryCompact                           = "session.history.compact";
inline constexpr const char* kSessionHistoryTruncate                          = "session.history.truncate";

inline constexpr const char* kSessionUsageGetMetrics                          = "session.usage.getMetrics";

inline constexpr const char* kSessionRemoteEnable                             = "session.remote.enable";
inline constexpr const char* kSessionRemoteDisable                            = "session.remote.disable";

// =============================================================================
// Legacy / pre-v3 helpers that the C++ port still invokes against the CLI.
// They are not in the generated rpc.ts namespace but remain on the wire for
// backward compatibility with the v2 protocol. Listed here so call sites can
// reference a single symbol.
// =============================================================================

inline constexpr const char* kAuthGetStatus       = "auth.getStatus";
inline constexpr const char* kStatusGet           = "status.get";

inline constexpr const char* kSessionCreate       = "session.create";
inline constexpr const char* kSessionResume       = "session.resume";
inline constexpr const char* kSessionList         = "session.list";
inline constexpr const char* kSessionGetMetadata  = "session.getMetadata";
inline constexpr const char* kSessionDelete       = "session.delete";
inline constexpr const char* kSessionGetLastId    = "session.getLastId";
inline constexpr const char* kSessionDestroy      = "session.destroy";
inline constexpr const char* kSessionDetach       = "session.detach";
inline constexpr const char* kSessionSend         = "session.send";
inline constexpr const char* kSessionAbort        = "session.abort";
inline constexpr const char* kSessionGetMessages  = "session.getMessages";
inline constexpr const char* kSessionGetForeground = "session.getForeground";
inline constexpr const char* kSessionSetForeground = "session.setForeground";

// Server-to-client: the runtime asks the SDK host for a GitHub credential.
inline constexpr const char* kGitHubTokenGetToken = "gitHubToken.getToken";

} // namespace copilot::rpc::methods

namespace copilot::rpc
{

/// Method-keyed request dispatcher.
///
/// Thin facade over `JsonRpcClient::set_request_handler` that lets callers
/// register per-method handlers — mirroring the shape of the upstream
/// `registerClientSessionApiHandlers` helper in `generated/rpc.ts`. The
/// dispatcher owns a single demux callback installed on the client and
/// looks up the registered handler for each incoming request by method name.
///
/// Thread-safety: registrations are serialized through an internal mutex.
/// Dispatch itself runs on the JSON-RPC read thread; handlers must be
/// reasonably quick or off-load work to another thread.
class RpcRequestDispatcher
{
  public:
    using Handler = std::function<json(const json& params)>;

    /// Construct, but do NOT install on a client yet. Use `attach()`.
    RpcRequestDispatcher() = default;

    /// Construct and install on `client` immediately.
    explicit RpcRequestDispatcher(JsonRpcClient& client) { attach(client); }

    /// Install this dispatcher as the request handler of `client`.
    /// Any previously-installed handler is overwritten.
    void attach(JsonRpcClient& client)
    {
        client.set_request_handler(
            [this](const std::string& method, const json& params) -> json
            {
                return dispatch(method, params);
            });
    }

    /// Register `handler` for `method`. Overwrites any previous registration.
    void on(const std::string& method, Handler handler)
    {
        std::lock_guard<std::mutex> lock(mu_);
        handlers_[method] = std::move(handler);
    }

    /// Remove the handler for `method` (no-op if not registered).
    void off(const std::string& method)
    {
        std::lock_guard<std::mutex> lock(mu_);
        handlers_.erase(method);
    }

    /// Check whether a handler is registered for `method`.
    bool has(const std::string& method) const
    {
        std::lock_guard<std::mutex> lock(mu_);
        return handlers_.find(method) != handlers_.end();
    }

    /// Number of registered handlers (mostly useful for tests).
    std::size_t size() const
    {
        std::lock_guard<std::mutex> lock(mu_);
        return handlers_.size();
    }

    /// Directly dispatch a request — exposed so tests can exercise routing
    /// without spinning up a transport. Throws `JsonRpcError` (method
    /// not found) if no handler is registered, matching the JSON-RPC 2.0
    /// behavior of the underlying client.
    json dispatch(const std::string& method, const json& params)
    {
        Handler handler;
        {
            std::lock_guard<std::mutex> lock(mu_);
            auto it = handlers_.find(method);
            if (it != handlers_.end())
                handler = it->second;
        }
        if (!handler)
        {
            throw JsonRpcError(
                JsonRpcErrorCode::MethodNotFound,
                "No handler registered for method: " + method);
        }
        return handler(params);
    }

  private:
    mutable std::mutex mu_;
    std::unordered_map<std::string, Handler> handlers_;
};

} // namespace copilot::rpc