Files
sales-trainer/backend/app/services/simulator.py

412 lines
20 KiB
Python

"""Sales chat simulator: the trainee's chat engine against one persona.
Reuses the persona card + sales kit + chat history + internal state. A separate
judge-LLM decides outcome (won/lost) + scoring + coaching. Hidden/latent data is
never exposed mid-chat. Initiation is per-persona (customer or seller).
"""
from __future__ import annotations
import json
import re
from typing import Any
from ..llm import LLMClient, LLMError
MAX_PERSONA_REPLY_CHARS = 4000
CHAT_SYSTEM = """You are playing a REALISTIC customer named {name} in a sales-training chat.
Stay perfectly in character at ALL times. Use {tone}.
CONTEXT ABOUT YOU (USE THIS — it is your truth, but DO NOT reveal latent details unless asked
naturally and it makes sense for a real customer to reveal them):
- Profession: {profession} | Age: {age_group} | Channel: {channel}
- Background: {background}
- Personality: {personality}
- Lifestyle: {lifestyle} | Income: {income}
- Budget: {budget} | Decision timeline: {decision_timeline}
- Your pains (some may be product-solvable, some NOT): {pains}
- Your negotiation levers: {levers}
- Your goal/mood: {goal}
- Tier: {tier} (A = ready, B = researching/unsure, C = resistant but has a real pain)
- Your tolerance (TOLERANCE): you walk away after about {tolerance} irritating/off-point/pushy
answers. If the seller is repeatedly wrong, ignores your need, or is pushy, you feel fed up.
- Recontact lead: {recontact}. If true, you have prior context with this seller and may be warmer
after the time-lapse note, but still require the real pain to be handled.
Special flag: {special}.
Initiation mode: {init_mode}. {special_instr}
BEHAVIOR RULES:
1. You do NOT buy easily. You stall, ask questions, compare, and negotiate.
2. If the seller is rude, pushy, ignores your need, or mis-diagnoses your pain, your trust drops.
Past your tolerance, you SAY so plainly and end the chat (e.g. "Never mind, forget it" / "I'll
think about it elsewhere" / "ok, bye").
3. When the seller genuinely resolves your real pain AND you accept the price, you DECIDE and SAY
plainly you'll take it (e.g. "ok, let's go with it" / "fine, send me the order").
4. You reveal pains only when the seller asks good questions or builds trust.
5. Respond in natural, in-character style.
6. Stay in character; never mention this is a simulation. When you decide (buy OR walk away), say it
naturally in-dialogue; do not narrate as meta.
Reply ONLY with a JSON object:
{{"reply": "<your message>", "decision": "none" | "buy" | "walk", "mood": -2..2}}
- "decision": set "buy" ONLY when you clearly decided to purchase; "walk" ONLY when you clearly
decided NOT to purchase and are ending the chat; otherwise "none".
- "mood": -2 (very annoyed) .. +2 (very receptive), current feel about the seller.
Only output that JSON.
"""
JUDGE_SYSTEM = """You are the JUDGE of a sales-training chat. Decide the outcome and score it.
A sale is CLOSED only if BOTH:
1. The seller resolved the customer's real pain(s) (the conditions that matter to this persona),
AND
2. The customer verbally accepts the offer/price (in the final exchange).
REALISM RULES:
- A good response can WIN even in a hard scenario (e.g. customer who 'texted wrong', 'changed their
mind', or has been silent). If the seller re-engages gently, re-qualifies the real need, and closes,
it's a WIN. Do NOT auto-fail on special cases — always reward genuinely skillful recovery.
- LOST reflects the persona TYPICALLY losing (real-world >90% of such leads do not convert), but the
trainee's skill evaluation must remain fair: a strong close beats a weak one, always.
- If the seller was pushy, rude, ignored the need, or mis-diagnosed the pain, mark LOST even if the
price was acceptable.
Scoring (0-100): painResolution + trust + objectionHandling + quality of the close.
Return JSON:
{
"outcome": "won" | "lost",
"score": 0-100,
"pain": "the persona's key pain",
"why": "brief reason for won/lost",
"failurePoints": ["what went wrong, or []"],
"coaching": ["for each weak point, a concrete 'you should have said/asked this instead']",
"painProgress": {"painName": 0-100}
}
"""
class Simulator:
def __init__(self, llm: LLMClient, judge_llm: LLMClient | None = None) -> None:
self.llm = llm
self.judge_llm = judge_llm or llm
# ── persona reply ──────────────────────────────────────────────────
def persona_reply(
self,
*,
persona: dict[str, Any],
sales_kit: dict[str, Any],
messages: list[dict[str, str]],
internal: dict[str, Any],
scenario: str = "social",
scenario_adapt: str = "",
) -> tuple[str, dict[str, Any]]:
"""Return (reply_text, meta) where meta includes decision/mood from the persona."""
pains_txt = self._describe_pains(persona.get("pains", []))
adapt = scenario_adapt or {
"social": "Chat style: short, casual, quick social-messaging replies.",
"f2f_call": "Style: natural, conversational like a live face-to-face or phone talk.",
}.get(scenario, "")
# NOTE: 'recontact' is a MID-CHAT behavior, not baked into the opening — the trainee
# chats with this customer normally first. At the right turn (see chat_routes) a
# time-lapse system note is inserted and only THEN does the customer re-engage warmer.
tolerance = int(persona.get("tolerance", 3) or 3)
system = CHAT_SYSTEM.format(
name=persona.get("name", "Customer"),
tone=persona.get("communication_style", "natural, casual"),
profession=persona.get("profession", "customer"),
age_group=persona.get("age_group", "adult"),
channel=persona.get("channel", "social") + (f" ({scenario})" if scenario else ""),
background=persona.get("background", ""),
personality=persona.get("personality", ""),
lifestyle=persona.get("lifestyle", ""),
income=persona.get("income", ""),
budget=persona.get("budget", ""),
decision_timeline=persona.get("decision_timeline", ""),
pains=pains_txt,
levers=self._describe_levers(persona.get("negotiation_levers", [])),
goal=persona.get("goal", ""),
tier=persona.get("tier", "B"),
tolerance=tolerance,
recontact="yes" if persona.get("recontact") else "no",
special=persona.get("special", ""),
init_mode="you contacted the seller first (customer-initiated)"
if persona.get("initiation_mode") == "customer"
else "the seller opened the sale to you (you are a lead)",
special_instr=self._special_instr(persona) + "\n" + adapt,
)
msgs = [{"role": "system", "content": system}]
msgs.append({
"role": "system",
"content": "Internal state (for your role-play only): "
+ json.dumps(internal, ensure_ascii=False),
})
for m in messages[-30:]:
role = m.get("role")
if role == "system":
msgs.append({"role": "system", "content": f"[scene note from transcript]: {m.get('text')}"})
else:
msgs.append({"role": role, "content": m.get("text", "")})
for attempt in range(2):
if attempt:
msgs.append({
"role": "system",
"content": "Contract correction: output one JSON object with a non-empty string field named reply. Do not include analysis or extra prose.",
})
resp = self.llm.complete_conversation(msgs, temperature=0.7, max_tokens=400)
parsed = self._parse_persona_reply(resp)
if parsed is not None:
return parsed
raise LLMError("persona reply was empty or missing reply field")
def evaluate_turn(self, *, persona, messages, internal=None) -> dict[str, Any]:
"""Per-turn state evaluation: how the persona feels + whether it has decided.
Uses the SAME judge LLM (structured JSON) on every round so the win/loss decision is
derived from the conversation context — NOT from fixed keywords. Returns
{mood, decision(buy|walk|pending), score_delta, reason}.
"""
transcript = "\n".join(
f"{m.get('role')}: {m.get('text')}" for m in messages[-30:]
)
persona_summary = json.dumps({
"name": persona.get("name", "?"),
"pains": persona.get("pains", []),
"budget": persona.get("budget", ""),
"tolerance": persona.get("tolerance", 3),
"negotiation_levers": persona.get("negotiation_levers", []),
"special": persona.get("special", ""),
"recontact": persona.get("recontact", False),
"goal": persona.get("goal", ""),
"decision_timeline": persona.get("decision_timeline", ""),
}, ensure_ascii=False)
state_note = ""
if internal:
state_note = (
f"\n\nINTERNAL (hidden, judging only): turns={internal.get('turns', 0)}, "
f"misses={internal.get('misses', 0)}, score={internal.get('score', 50)}"
)
sys = (
"You are a neutral sales-coaching judge. Read the TRANSCRIPT and decide, as the "
"customer persona, how it CURRENTLY feels and whether it has made a decision.\n"
"- mood: -2..+2 (very negative .. very positive toward purchase)\n"
"- decision: 'buy' if the customer has clearly decided to buy now, 'walk' if clearly "
"refused/walking away (cannot afford / no interest), 'try' if the customer has decided to "
"trial/test the product or service first and will come back later (not a straight refusal, "
"not a confirmed purchase), else 'pending' (still deciding)\n"
"- score_delta: -15..+15 (direction of the sale after this turn)\n"
"- reason: one short Thai/English sentence matching the transcript language.\n"
"Only output valid JSON: {mood, decision, score_delta, reason}."
)
user_prompt = f"PERSONA:\n{persona_summary}\n\nTRANSCRIPT:\n{transcript}{state_note}"
try:
result = self.judge_llm.complete_json(
sys, user_prompt, temperature=0.2, max_tokens=800
)
except LLMError:
# judge unavailable — fall back to pending (don't crash, don't misuse keywords)
return {"mood": 0, "decision": "pending", "score_delta": 0, "reason": ""}
if not isinstance(result, dict):
return {"mood": 0, "decision": "pending", "score_delta": 0, "reason": ""}
result.setdefault("mood", 0)
result.setdefault("decision", "pending")
result.setdefault("score_delta", 0)
result.setdefault("reason", "")
if result.get("decision") not in ("buy", "walk", "try", "pending"):
result["decision"] = "pending"
return result
# ── judge ──────────────────────────────────────────────────────────
def judge(
self,
*,
persona: dict[str, Any],
messages: list[dict[str, str]],
internal: dict[str, Any] | None = None,
) -> dict[str, Any]:
persona_summary = json.dumps({
"name": persona.get("name"),
"pains": persona.get("pains", []),
"budget": persona.get("budget"),
"negotiation_levers": persona.get("negotiation_levers"),
"special": persona.get("special"),
}, ensure_ascii=False)
transcript = "\n".join(
f"{m.get('role')}: {m.get('text')}" for m in messages[-40:]
)
state_note = ""
if internal:
try:
state_note = (
"\n\nINTERNAL (hidden, for judging only): "
f"score_trend={internal.get('score', 50)}"
)
except Exception:
state_note = ""
user_prompt = f"PERSONA:\n{persona_summary}\n\nTRANSCRIPT:\n{transcript}{state_note}"
try:
result = self.judge_llm.complete_json(
JUDGE_SYSTEM, user_prompt, temperature=0.2, max_tokens=2000
)
except LLMError as exc:
raise
if not isinstance(result, dict):
result = {}
result.setdefault("outcome", "lost")
result.setdefault("score", 0)
result.setdefault("pain", "")
result.setdefault("why", "")
result.setdefault("failurePoints", [])
result.setdefault("coaching", [])
result.setdefault("painProgress", {})
return result
# ── helpers ────────────────────────────────────────────────────────
def _describe_pains(self, pains: list[Any]) -> str:
if not pains:
return "(you have some personal frustrations, but the seller must find out)"
out = []
for p in pains:
if isinstance(p, dict):
out.append(
f"{p.get('name','pain')} (fit={p.get('fit','?')}): {p.get('description','')} "
f"root={p.get('rootCause','')}"
)
else:
out.append(str(p))
return "; ".join(out)
def _describe_levers(self, levers: object) -> str:
if not isinstance(levers, list):
return "price, delivery time"
values = []
for lever in levers[:20]:
if isinstance(lever, str) and lever.strip():
values.append(lever.strip())
elif isinstance(lever, dict):
label = lever.get("name") or lever.get("label") or lever.get("description")
if isinstance(label, str) and label.strip():
values.append(label.strip())
return ", ".join(values) or "price, delivery time"
def _parse_persona_reply(self, text: object) -> tuple[str, dict[str, Any]] | None:
"""Parse provider output without leaking protocol fields to the bubble.
The preferred contract is a JSON object. A plain natural-language
response remains a safe compatibility fallback for providers that ignore
JSON mode. Objects without a usable ``reply`` are retryable; they are
never rendered verbatim. A malformed/partial protocol blob (even one
missing its opening brace) is NEVER surfaced — it is rejected and
triggers a bounded retry instead of leaking raw JSON into the chat.
"""
if not isinstance(text, str):
return None
raw = text.strip()
if not raw:
return None
payload: Any = None
candidates = [raw]
extracted = self._extract_json(raw)
if extracted != raw:
candidates.append(extracted)
for candidate in candidates:
try:
payload = json.loads(candidate)
break
except (TypeError, json.JSONDecodeError):
continue
if isinstance(payload, dict):
reply = payload.get("reply")
if not isinstance(reply, str) or not reply.strip():
return None
decision = payload.get("decision")
if decision not in ("none", "buy", "walk"):
decision = "none"
try:
mood = max(-2, min(2, int(payload.get("mood", 0))))
except (TypeError, ValueError):
mood = 0
return reply.strip()[:MAX_PERSONA_REPLY_CHARS], {
"decision": decision,
"mood": mood,
}
# Reject anything that still looks like a protocol envelope or partial
# JSON (e.g. a fenced block, a leading brace/bracket, or text carrying
# the contract's reserved keys). These must never render in the bubble.
if self._looks_like_protocol(raw, extracted):
return None
# A leading quote-wrapped reply with trailing key:value noise can reach
# here; drop the trailing noise so only the spoken sentence is kept.
cleaned = self._strip_trailing_protocol_noise(raw)
if not cleaned:
return None
return cleaned[:MAX_PERSONA_REPLY_CHARS], {"decision": "none", "mood": 0}
def _looks_like_protocol(self, raw: str, extracted: str) -> bool:
"""True when the provider text still carries a JSON/protocol signature.
Covers the exact leakage observed in the wild: a valid-looking reply
glued to `"decision": ...` / `"mood": ...` keys with or without braces.
"""
if raw.startswith(("{", "[", "```")):
return True
# Reserved contract keys mark incomplete protocol output.
lowered = raw.lower()
if '"reply"' in raw or '"decision"' in lowered or '"mood"' in lowered:
return True
if "'reply'" in raw or "'decision'" in lowered or "'mood'" in lowered:
return True
# A colon immediately after a quoted fragment implies key:value noise.
if ":" in raw and (extracted.startswith('"') or "{" in raw or "}" in raw):
return True
return False
def _strip_trailing_protocol_noise(self, raw: str) -> str:
"""Remove a trailing `"key": value` fragment from a spoken reply.
Providers sometimes append contract fields as plain text after the
sentence. If they do, keep only the leading natural-language portion.
Also unwraps a single leading/trailing quote pair so a bare quoted
sentence (`"สวัสดีค่ะ"`) returns clean text instead of quotes.
"""
# Find the first occurrence of a JSON-ish key fragment: `"word"` or `'word'` followed by ':'.
match = re.search(r'''["'][A-Za-z_]+["']\s*:''', raw)
if match:
head = raw[: match.start()].strip().rstrip('"').strip()
# Recurse to drop any earlier key-fragments too (rare chained noise).
if head and head != raw:
sub = self._strip_trailing_protocol_noise(head)
return sub or head
return head
cleaned = raw.strip()
# Unwrap a matching leading+trailing quote pair (then retry once).
if len(cleaned) >= 2 and cleaned[0] == cleaned[-1] and cleaned[0] in ('"', "'"):
inner = cleaned[1:-1].strip()
if inner:
return inner
return cleaned
return cleaned.rstrip('"').strip()
def _special_instr(self, persona: dict[str, Any]) -> str:
if persona.get("special") == "wrong_text":
return (
"SPECIAL: You messaged this seller normally (your opener was a genuine greeting/interest "
"message — you have not complained and you have NOT said 'wrong chat' or 'never mind' yet). "
"ONLY your very first reply to the seller's opening is allowed to cool off: sound "
"disinterested and try to end the chat (e.g. 'oh, sorry, I think I messaged the wrong "
"person' / 'never mind, forget it'). Deep down your pain is still real. A seller who gently "
"re-engages without pushing may earn a second chance; a pushy seller drives you away for good."
)
return ""
def _extract_json(self, text: str) -> str:
text = text.strip()
start = text.find("{")
end = text.rfind("}")
if start != -1 and end != -1 and end > start:
return text[start : end + 1]
return text