| 1 | package control |
| 2 | |
| 3 | import ( |
| 4 | "context" |
| 5 | "fmt" |
| 6 | "strconv" |
| 7 | |
| 8 | "reasonix/internal/event" |
| 9 | "reasonix/internal/mcpinteraction" |
| 10 | "reasonix/internal/provider" |
| 11 | ) |
| 12 | |
| 13 | // pendingMCPInteraction is one server-initiated elicitation awaiting the user's |
| 14 | // accept/decline/cancel. |
| 15 | type pendingMCPInteraction struct { |
| 16 | request event.MCPInteraction |
| 17 | reply chan mcpinteraction.Result |
| 18 | queued bool |
| 19 | } |
| 20 | |
| 21 | // mcpInteractionState groups the elicitation bookkeeping so the mutex-guarded |
| 22 | // approvalManager ratchets by one field, not one per map. |
| 23 | type mcpInteractionState struct { |
| 24 | pending map[string]pendingMCPInteraction |
| 25 | resolutions map[string]*promptResolution |
| 26 | } |
| 27 | |
| 28 | func (a *approvalManager) registerMCPInteraction(req mcpinteraction.Request) (string, chan mcpinteraction.Result) { |
| 29 | a.mu.Lock() |
| 30 | defer a.mu.Unlock() |
| 31 | if a.mcpInteractions.pending == nil { |
| 32 | a.mcpInteractions.pending = map[string]pendingMCPInteraction{} |
| 33 | a.mcpInteractions.resolutions = map[string]*promptResolution{} |
| 34 | } |
| 35 | a.nextID++ |
| 36 | id := strconv.Itoa(a.nextID) |
| 37 | reply := make(chan mcpinteraction.Result, 1) |
| 38 | a.mcpInteractions.pending[id] = pendingMCPInteraction{ |
| 39 | request: event.MCPInteraction{ |
| 40 | ID: id, Server: req.Server, Mode: req.Mode, Message: req.Message, |
| 41 | RequestedSchema: append([]byte(nil), req.RequestedSchema...), |
| 42 | URL: req.URL, ElicitationID: req.ElicitationID, |
| 43 | }, |
| 44 | reply: reply, |
| 45 | queued: true, |
| 46 | } |
| 47 | return id, reply |
| 48 | } |
| 49 | |
| 50 | func (a *approvalManager) markMCPInteractionEmitted(id string) { |
| 51 | a.mu.Lock() |
| 52 | defer a.mu.Unlock() |
| 53 | if p, ok := a.mcpInteractions.pending[id]; ok { |
| 54 | p.queued = false |
| 55 | a.mcpInteractions.pending[id] = p |
| 56 | } |
| 57 | } |
| 58 | |
| 59 | func (a *approvalManager) cancelMCPInteraction(id string) { |
| 60 | a.mu.Lock() |
| 61 | delete(a.mcpInteractions.pending, id) |
| 62 | if attempt := a.mcpInteractions.resolutions[id]; attempt != nil { |
| 63 | a.finishMCPInteractionResolutionLocked(id, attempt, context.Canceled) |
| 64 | } |
| 65 | a.mu.Unlock() |
| 66 | } |
| 67 | |
| 68 | func (a *approvalManager) finishMCPInteractionResolutionLocked(id string, attempt *promptResolution, err error) { |
| 69 | if attempt == nil || a.mcpInteractions.resolutions[id] != attempt { |
| 70 | return |
| 71 | } |
| 72 | delete(a.mcpInteractions.resolutions, id) |
| 73 | attempt.err = err |
| 74 | close(attempt.done) |
| 75 | } |
| 76 | |
| 77 | // resolveMCPInteractionAfter mirrors resolveAskAfter: the durable |
| 78 | // PromptAnswered transition is persisted before the waiter is released. |
| 79 | func (a *approvalManager) resolveMCPInteractionAfter(id string, persist func(pendingMCPInteraction) error) (pendingMCPInteraction, bool, error) { |
| 80 | a.mu.Lock() |
| 81 | p, ok := a.mcpInteractions.pending[id] |
| 82 | if !ok { |
| 83 | a.mu.Unlock() |
| 84 | return pendingMCPInteraction{}, false, nil |
| 85 | } |
| 86 | if inFlight := a.mcpInteractions.resolutions[id]; inFlight != nil { |
| 87 | a.mu.Unlock() |
| 88 | return pendingMCPInteraction{}, false, inFlight.wait() |
| 89 | } |
| 90 | attempt := newPromptResolution() |
| 91 | a.mcpInteractions.resolutions[id] = attempt |
| 92 | a.mu.Unlock() |
| 93 | if persist != nil { |
| 94 | if err := persist(p); err != nil { |
| 95 | a.mu.Lock() |
| 96 | a.finishMCPInteractionResolutionLocked(id, attempt, err) |
| 97 | a.mu.Unlock() |
| 98 | return pendingMCPInteraction{}, false, err |
| 99 | } |
| 100 | } |
| 101 | a.mu.Lock() |
| 102 | defer a.mu.Unlock() |
| 103 | current, ok := a.mcpInteractions.pending[id] |
| 104 | if !ok || a.mcpInteractions.resolutions[id] != attempt || current.reply != p.reply { |
| 105 | if a.mcpInteractions.resolutions[id] == attempt { |
| 106 | a.finishMCPInteractionResolutionLocked(id, attempt, context.Canceled) |
| 107 | } |
| 108 | return pendingMCPInteraction{}, false, attempt.err |
| 109 | } |
| 110 | delete(a.mcpInteractions.pending, id) |
| 111 | a.finishMCPInteractionResolutionLocked(id, attempt, nil) |
| 112 | return p, true, nil |
| 113 | } |
| 114 | |
| 115 | // snapshotMCPInteractions copies emitted-but-unanswered elicitations for |
| 116 | // frontend replay; queued ones have never been shown and stay hidden. |
| 117 | func (a *approvalManager) snapshotMCPInteractions() []event.MCPInteraction { |
| 118 | a.mu.Lock() |
| 119 | defer a.mu.Unlock() |
| 120 | out := make([]event.MCPInteraction, 0, len(a.mcpInteractions.pending)) |
| 121 | for id, p := range a.mcpInteractions.pending { |
| 122 | if p.queued { |
| 123 | continue |
| 124 | } |
| 125 | interaction := p.request |
| 126 | interaction.ID = id |
| 127 | out = append(out, interaction) |
| 128 | } |
| 129 | return out |
| 130 | } |
| 131 | |
| 132 | // Interact implements mcpinteraction.Broker: it surfaces a server-initiated |
| 133 | // elicitation and blocks on that request's own cancellable reply channel. Form |
| 134 | // values and URL targets ride the resolve call only — nothing is logged here. |
| 135 | func (c *Controller) Interact(ctx context.Context, req mcpinteraction.Request) (mcpinteraction.Result, error) { |
| 136 | c.approval.promptEmitMu.Lock() |
| 137 | id, reply := c.approval.registerMCPInteraction(req) |
| 138 | c.registerOwnedPrompt(id, PromptMCP) |
| 139 | payload := event.MCPInteraction{ |
| 140 | ID: id, Server: req.Server, Mode: req.Mode, Message: req.Message, |
| 141 | RequestedSchema: append([]byte(nil), req.RequestedSchema...), |
| 142 | URL: req.URL, ElicitationID: req.ElicitationID, |
| 143 | } |
| 144 | payload.TurnID, _, _, _ = c.turnEventRuntimeStatus() |
| 145 | _, runtimeEpoch := c.promptIdentitySnapshot() |
| 146 | if identity := c.bindOwnedPromptRouting(id, payload.TurnID, runtimeEpoch); identity.TurnID != "" { |
| 147 | payload.TurnID = identity.TurnID |
| 148 | } |
| 149 | if err := event.EmitChecked(c.sink, event.Event{Kind: event.MCPInteractionRequest, TurnID: payload.TurnID, ItemID: id, MCPInteraction: payload}); err != nil { |
| 150 | c.approval.promptEmitMu.Unlock() |
| 151 | c.cancelOwnedPrompt(id) |
| 152 | return mcpinteraction.Result{Action: mcpinteraction.ActionCancel}, fmt.Errorf("persist elicitation request: %w", err) |
| 153 | } |
| 154 | c.approval.markMCPInteractionEmitted(id) |
| 155 | c.approval.promptEmitMu.Unlock() |
| 156 | |
| 157 | waitCtx, cancelWait := c.approval.waitContext(ctx) |
| 158 | defer cancelWait() |
| 159 | |
| 160 | select { |
| 161 | case res := <-reply: |
| 162 | return res, nil |
| 163 | case <-waitCtx.Done(): |
| 164 | c.cancelOwnedPrompt(id) |
| 165 | return mcpinteraction.Result{Action: mcpinteraction.ActionCancel}, waitCtx.Err() |
| 166 | } |
| 167 | } |
| 168 | |
| 169 | // AnswerMCPInteraction resolves a pending elicitation with the user's action |
| 170 | // (accept/decline/cancel) and, for accept, the submitted form values. |
| 171 | func (c *Controller) AnswerMCPInteraction(id, action string, content map[string]any) { |
| 172 | _ = c.AnswerMCPInteractionChecked(id, action, content) |
| 173 | } |
| 174 | |
| 175 | // AnswerMCPInteractionChecked persists the prompt transition before releasing |
| 176 | // the blocked MCP call, so a crashed frontend cannot lose an answered decision. |
| 177 | func (c *Controller) AnswerMCPInteractionChecked(id, action string, content map[string]any) error { |
| 178 | defer c.refreshRuntimeState(event.Event{}) |
| 179 | return c.answerMCPInteractionCheckedLocked(id, action, content) |
| 180 | } |
| 181 | |
| 182 | func (c *Controller) answerMCPInteractionCheckedLocked(id, action string, content map[string]any) error { |
| 183 | switch action { |
| 184 | case mcpinteraction.ActionAccept, mcpinteraction.ActionDecline, mcpinteraction.ActionCancel: |
| 185 | default: |
| 186 | return fmt.Errorf("invalid elicitation action %q", action) |
| 187 | } |
| 188 | if action != mcpinteraction.ActionAccept { |
| 189 | content = nil |
| 190 | } |
| 191 | pending, ok, err := c.approval.resolveMCPInteractionAfter(id, func(p pendingMCPInteraction) error { |
| 192 | state := PromptAnswered |
| 193 | switch action { |
| 194 | case mcpinteraction.ActionDecline: |
| 195 | state = PromptRejected |
| 196 | case mcpinteraction.ActionCancel: |
| 197 | state = PromptCancelled |
| 198 | } |
| 199 | return c.emitTurnEventChecked(event.Event{Kind: event.PromptAnswered, ItemID: id, InteractionState: string(state), Status: event.TurnInProgress}) |
| 200 | }) |
| 201 | if err != nil { |
| 202 | return err |
| 203 | } |
| 204 | if ok { |
| 205 | terminal := PromptAnswered |
| 206 | switch action { |
| 207 | case mcpinteraction.ActionDecline: |
| 208 | terminal = PromptRejected |
| 209 | case mcpinteraction.ActionCancel: |
| 210 | terminal = PromptCancelled |
| 211 | } |
| 212 | c.promptOwner.MarkIDTerminal(id, terminal) |
| 213 | c.recordMCPInteractionReceipt(id, pending, action) |
| 214 | pending.reply <- mcpinteraction.Result{Action: action, Content: content} |
| 215 | } |
| 216 | return nil |
| 217 | } |
| 218 | |
| 219 | func (c *Controller) recordMCPInteractionReceipt(id string, pending pendingMCPInteraction, action string) { |
| 220 | if c == nil || c.executor == nil { |
| 221 | return |
| 222 | } |
| 223 | receipt := &provider.DecisionReceipt{ |
| 224 | ID: id, |
| 225 | Kind: "mcp_elicitation", |
| 226 | Subject: clipUTF8(pending.request.Server+" elicitation ("+pending.request.Mode+")", 240), |
| 227 | Outcome: action, |
| 228 | } |
| 229 | c.executor.Session().AddDecisionReceipt(receipt) |
| 230 | } |
| 231 |