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
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
|
import type { AgentEvent, Chunk, StoredChunk } from "@dispatch/wire";
import type { AccumulatingChunk, ProvisionalChunk, TranscriptState } from "./types";
/** The initial empty transcript state. */
export function initialState(): TranscriptState {
return {
committed: [],
provisional: [],
accumulating: null,
currentTurnId: null,
latestUsage: null,
sealedTurnId: null,
};
}
function flushAccumulating(
provisional: readonly ProvisionalChunk[],
acc: AccumulatingChunk | null,
): readonly ProvisionalChunk[] {
if (acc === null) return provisional;
const chunk: Chunk =
acc.kind === "text" ? { type: "text", text: acc.text } : { type: "thinking", text: acc.text };
return [...provisional, { role: "assistant", chunk }];
}
/**
* Merge authoritative seq-keyed chunks into the committed history.
* Dedupes by seq (new wins), keeps seq-monotonic order, idempotent.
* When sealedTurnId is set, drops all provisional chunks (now superseded)
* and clears sealedTurnId.
*/
export function applyHistory(
state: TranscriptState,
chunks: readonly StoredChunk[],
): TranscriptState {
const seqMap = new Map<number, StoredChunk>();
for (const c of state.committed) seqMap.set(c.seq, c);
for (const c of chunks) seqMap.set(c.seq, c);
const committed = Array.from(seqMap.values()).sort((a, b) => a.seq - b.seq);
if (state.sealedTurnId !== null) {
return {
...state,
committed,
provisional: [],
accumulating: null,
sealedTurnId: null,
};
}
return { ...state, committed };
}
/**
* Fold one live AgentEvent into the provisional state.
*
* - `turn-start` records the turnId.
* - `text-delta` extends the current accumulating TextChunk (or starts one).
* - `reasoning-delta` extends the current accumulating ThinkingChunk (or starts one).
* - `tool-call` / `tool-result` / `error` finalize any accumulating chunk and
* add a new provisional chunk.
* - `usage` stores the latest Usage.
* - `done` finalizes any accumulating chunk (turn still provisional).
* - `turn-sealed` finalizes any accumulating chunk and sets sealedTurnId.
* - `status` and `tool-output` are ignored (best-effort no-ops).
*/
export function foldEvent(state: TranscriptState, event: AgentEvent): TranscriptState {
switch (event.type) {
case "status":
case "tool-output":
return state;
case "turn-start":
return { ...state, currentTurnId: event.turnId };
case "text-delta": {
const acc = state.accumulating;
if (acc !== null && acc.kind === "text") {
return { ...state, accumulating: { kind: "text", text: acc.text + event.delta } };
}
const provisional = flushAccumulating(state.provisional, acc);
return {
...state,
provisional,
accumulating: { kind: "text", text: event.delta },
};
}
case "reasoning-delta": {
const acc = state.accumulating;
if (acc !== null && acc.kind === "thinking") {
return { ...state, accumulating: { kind: "thinking", text: acc.text + event.delta } };
}
const provisional = flushAccumulating(state.provisional, acc);
return {
...state,
provisional,
accumulating: { kind: "thinking", text: event.delta },
};
}
case "tool-call": {
const provisional = flushAccumulating(state.provisional, state.accumulating);
const chunk: Chunk = {
type: "tool-call",
toolCallId: event.toolCallId,
toolName: event.toolName,
input: event.input,
};
return {
...state,
provisional: [...provisional, { role: "assistant", chunk }],
accumulating: null,
};
}
case "tool-result": {
const provisional = flushAccumulating(state.provisional, state.accumulating);
const chunk: Chunk = {
type: "tool-result",
toolCallId: event.toolCallId,
toolName: event.toolName,
content: event.content,
isError: event.isError,
};
return {
...state,
provisional: [...provisional, { role: "tool", chunk }],
accumulating: null,
};
}
case "error": {
const provisional = flushAccumulating(state.provisional, state.accumulating);
const chunk: Chunk =
event.code !== undefined
? { type: "error", message: event.message, code: event.code }
: { type: "error", message: event.message };
return {
...state,
provisional: [...provisional, { role: "assistant", chunk }],
accumulating: null,
};
}
case "usage":
return { ...state, latestUsage: event.usage };
case "done": {
const provisional = flushAccumulating(state.provisional, state.accumulating);
return {
...state,
provisional,
accumulating: null,
};
}
case "turn-sealed": {
const provisional = flushAccumulating(state.provisional, state.accumulating);
return {
...state,
provisional,
accumulating: null,
sealedTurnId: event.turnId,
};
}
}
}
/**
* Optimistically append a user message to the provisional list.
* Flushes any in-progress accumulating chunk first (defensively).
* The provisional user chunk is superseded when applyHistory receives
* the authoritative committed chunks after a turn seals.
*/
export function appendUserMessage(state: TranscriptState, text: string): TranscriptState {
const provisional = flushAccumulating(state.provisional, state.accumulating);
const userChunk: Chunk = { type: "text", text };
return {
...state,
provisional: [...provisional, { role: "user", chunk: userChunk }],
accumulating: null,
};
}
|
