File size: 4,892 Bytes
e8a6c67
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
caa28aa
 
e8a6c67
 
 
 
 
 
 
 
 
 
 
 
 
 
 
9dff1b6
 
 
e8a6c67
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
/**
 * SSE client for the Riprap agent stream (`GET /api/agent/stream?q=…`).
 *
 * The FastAPI backend emits these events:
 *   hello            { query }
 *   plan_token       { delta }                             planner JSON, token-by-token
 *   plan             { intent, targets, specialists, ... } planner finished
 *   step             { step, ok, started_at, elapsed_s, result?, err? }
 *   token            { delta, attempt? }                   reconciler tokens (the briefing)
 *   mellea_attempt   { attempt, passed, failed }
 *   final            { paragraph, mellea, audit, tier, score, ... }
 *   error            { err }
 *   done             {}
 *
 * The handoff component contract talks about `token` (with section/claimId)
 * and `claim` boundary events. We don't ask the backend to emit those —
 * instead this client parses the streaming markdown into the four-section
 * Briefing structure, infers tier per claim from cited doc-id family
 * prefixes (see tierForDocId), and emits sentence-buffered chunks to a
 * subscriber for accessible aria-live updates.
 */
import type { Tier } from '$lib/types/tier';

export interface PlanInfo {
  intent: string;
  targets?: unknown;
  specialists?: string[];
  rationale?: string;
}

export interface StepEvent {
  step: string;
  ok: boolean;
  elapsed_s?: number;
  result?: unknown;
  err?: string;
  tier?: Tier | null;
  claims?: number;
  /** Present on compare-intent step events: "PLACE A" or "PLACE B". */
  target_label?: string;
}

export interface MelleaAttempt {
  attempt: number;
  passed: string[];
  failed: string[];
}

export interface FinalResult {
  paragraph: string;
  mellea?: { passed: string[]; failed: string[]; attempts: number };
  audit?: unknown;
  tier?: string;
  score?: number;
  citations?: Array<{ doc_id: string; source?: string; title?: string; url?: string; vintage?: string }>;
  /** Present when intent === "compare". */
  intent?: string;
  targets?: Array<{ label: string; address: string }>;
}

export interface AgentStreamHandlers {
  onHello?: (q: string) => void;
  onPlanToken?: (delta: string) => void;
  onPlan?: (plan: PlanInfo) => void;
  onStep?: (s: StepEvent) => void;
  /** Raw token, before sentence buffering. */
  onToken?: (delta: string, attempt: number | undefined) => void;
  /** Sentence-flushed chunk, safe for aria-live. */
  onSentence?: (sentence: string, attempt: number | undefined) => void;
  /** Fired when the reconciler restarts (a Mellea reroll wipes the buffer). */
  onAttemptStart?: (attempt: number) => void;
  onMelleaAttempt?: (m: MelleaAttempt) => void;
  onFinal?: (f: FinalResult) => void;
  onError?: (err: string) => void;
  onDone?: () => void;
}

export interface AgentStream {
  close(): void;
}

export function openAgentStream(query: string, handlers: AgentStreamHandlers): AgentStream {
  const url = `/api/agent/stream?q=${encodeURIComponent(query)}`;
  const es = new EventSource(url);

  let sentenceBuf = '';
  let currentAttempt: number | undefined;
  const SENT_END = /([.?!])(\s|$)/;

  function flushSentences(force = false) {
    let m: RegExpExecArray | null;
    while ((m = SENT_END.exec(sentenceBuf))) {
      const end = m.index + m[1].length + (m[2] ? m[2].length : 0);
      const sentence = sentenceBuf.slice(0, end).trim();
      sentenceBuf = sentenceBuf.slice(end);
      if (sentence) handlers.onSentence?.(sentence, currentAttempt);
    }
    if (force && sentenceBuf.trim()) {
      handlers.onSentence?.(sentenceBuf.trim(), currentAttempt);
      sentenceBuf = '';
    }
  }

  function on<T>(name: string, fn: (data: T) => void) {
    es.addEventListener(name, (e) => {
      try {
        fn(JSON.parse((e as MessageEvent).data) as T);
      } catch {
        /* ignore parse errors */
      }
    });
  }

  on<{ query: string }>('hello', (d) => handlers.onHello?.(d.query));
  on<{ delta: string }>('plan_token', (d) => handlers.onPlanToken?.(d.delta));
  on<PlanInfo>('plan', (d) => handlers.onPlan?.(d));
  on<StepEvent>('step', (d) => handlers.onStep?.(d));
  on<{ delta: string; attempt?: number }>('token', (d) => {
    if (d.attempt !== currentAttempt) {
      currentAttempt = d.attempt;
      sentenceBuf = '';
      handlers.onAttemptStart?.(d.attempt ?? 1);
    }
    handlers.onToken?.(d.delta, d.attempt);
    sentenceBuf += d.delta;
    flushSentences(false);
  });
  on<MelleaAttempt>('mellea_attempt', (d) => handlers.onMelleaAttempt?.(d));
  on<FinalResult>('final', (d) => {
    flushSentences(true);
    handlers.onFinal?.(d);
  });
  on<{ err: string }>('error', (d) => handlers.onError?.(d.err));
  es.addEventListener('done', () => {
    flushSentences(true);
    handlers.onDone?.();
    es.close();
  });
  es.addEventListener('error', () => {
    flushSentences(true);
    handlers.onError?.('SSE connection error');
    es.close();
  });

  return { close: () => es.close() };
}