chat_handler.py

"""
Flare – Chat Handler  (small-talk trim + resmî selamlama)
=========================================================
"""

import re, json, uuid, sys, httpx, commentjson
from datetime import datetime
from typing import Dict, List, Optional
from fastapi import APIRouter, HTTPException, Header
from pydantic import BaseModel
from commentjson import JSONLibraryException

from prompt_builder import build_intent_prompt, build_parameter_prompt, log


# ─────────────────────────
# HELPERS
# ─────────────────────────
def _trim_smalltalk(raw: str) -> str:
    """
    Kısa selamlaşma çıktısında yalnızca ilk blok (etiketsiz) kısmını döndürür.
    """
    # intent etiketi öncesini al
    pos_intent = raw.find("#DETECTED_INTENT")
    if pos_intent != -1:
        raw = raw[:pos_intent]

    # arka arkaya 'assistant' blokları varsa ilkini al
    pos_asst = raw.lower().find("assistant")
    if pos_asst != -1:
        raw = raw[:pos_asst]

    return raw.strip()


# ─────────────────────────
# CONFIG LOAD
# ─────────────────────────
def load_config(path: str = "service_config.jsonc") -> dict:
    try:
        with open(path, encoding="utf-8") as f:
            cfg = commentjson.load(f)
        log("✅ service_config.jsonc parsed successfully.")
        return cfg
    except (JSONLibraryException, FileNotFoundError) as e:
        log(f"❌ CONFIG ERROR: {e}")
        sys.exit(1)

CFG = load_config()
PROJECTS = {p["name"]: p for p in CFG["projects"]}
APIS     = {a["name"]: a for a in CFG["apis"]}
SPARK_URL = CFG["config"]["spark_endpoint"].rstrip("/") + "/generate"
ALLOWED_INTENTS = {"flight-booking", "flight-info", "booking-cancel"}


# ─────────────────────────
# SESSION
# ─────────────────────────
class Session:
    def __init__(self, project_name: str):
        self.id = str(uuid.uuid4())
        self.project = PROJECTS[project_name]
        self.history: List[Dict[str, str]] = []
        self.variables: Dict[str, str] = {}
        self.awaiting: Optional[Dict] = None
        log(f"🆕 Session {self.id} for {project_name}")

SESSIONS: Dict[str, Session] = {}


# ─────────────────────────
# SPARK CLIENT
# ─────────────────────────
async def spark_generate(session: Session,
                         system_prompt: str,
                         user_input: str) -> str:
    payload = {
        "project_name": session.project["name"],
        "user_input": user_input,
        "context": session.history[-10:],
        "system_prompt": system_prompt
    }
    async with httpx.AsyncClient(timeout=60) as c:
        r = await c.post(SPARK_URL, json=payload)
        r.raise_for_status()
        d = r.json()
        return (d.get("assistant") or d.get("model_answer") or d.get("text", "")).strip()


# ─────────────────────────
# FASTAPI ROUTER
# ─────────────────────────
router = APIRouter()

@router.get("/")
def health():
    return {"status": "ok"}

class StartSessionRequest(BaseModel):
    project_name: str
class ChatBody(BaseModel):
    user_input: str
class ChatResponse(BaseModel):
    session_id: str
    answer: str


# ─────────────────────────
# ENDPOINTS
# ─────────────────────────
@router.post("/start_session", response_model=ChatResponse)
async def start_session(req: StartSessionRequest):
    if req.project_name not in PROJECTS:
        raise HTTPException(404, "Unknown project")
    s = Session(req.project_name)
    SESSIONS[s.id] = s
    return ChatResponse(session_id=s.id, answer="Hoş geldiniz! Size nasıl yardımcı olabilirim?")

@router.post("/chat", response_model=ChatResponse)
async def chat(body: ChatBody, x_session_id: str = Header(...)):
    if x_session_id not in SESSIONS:
        raise HTTPException(404, "Invalid session")

    s = SESSIONS[x_session_id]
    user_msg = body.user_input.strip()
    s.history.append({"role": "user", "content": user_msg})

    # follow-up?
    if s.awaiting:
        answer = await _followup(s, user_msg)
        s.history.append({"role": "assistant", "content": answer})
        return ChatResponse(session_id=s.id, answer=answer)

    # intent detect
    gen_prompt  = s.project["versions"][0]["general_prompt"]
    intents_cfg = s.project["versions"][0]["intents"]
    intent_raw = await spark_generate(
        s,
        build_intent_prompt(gen_prompt, s.history, user_msg, intents_cfg),
        user_msg
    )

    # small-talk yolu
    if not intent_raw.startswith("#DETECTED_INTENT:"):
        clean = _trim_smalltalk(intent_raw)
        # Selamlama resmî değilse düzelt
        if "Hoşgeldin" in clean or "Hoş geldin" in clean:
            clean = clean.replace("Hoşgeldin", "Hoş geldiniz").replace("Hoş geldin", "Hoş geldiniz")
        s.history.append({"role": "assistant", "content": clean})
        return ChatResponse(session_id=s.id, answer=clean)

    intent_name = intent_raw.split(":", 1)[1].strip()

    # kısa mesaj guard
    if len(user_msg.split()) < 3:
        clean = _trim_smalltalk(intent_raw)
        s.history.append({"role": "assistant", "content": clean})
        return ChatResponse(session_id=s.id, answer=clean)

    # allowed-set
    if intent_name not in ALLOWED_INTENTS:
        clean = _trim_smalltalk(intent_raw)
        s.history.append({"role": "assistant", "content": clean})
        return ChatResponse(session_id=s.id, answer=clean)

    # intent handling ...
    intent_cfg = _find_intent(s.project, intent_name)
    if not intent_cfg:
        err = "Üzgünüm, anlayamadım."
        s.history.append({"role": "assistant", "content": err})
        return ChatResponse(session_id=s.id, answer=err)

    answer = await _handle_intent(s, intent_cfg, user_msg)
    s.history.append({"role": "assistant", "content": answer})
    return ChatResponse(session_id=s.id, answer=answer)

# --------------------------------------------------------------------------- #
# HELPER FUNCS (değişmeyen kısımlar)
# --------------------------------------------------------------------------- #
def _find_intent(project, name_):
    return next((i for i in project["versions"][0]["intents"] if i["name"] == name_), None)

def _missing(s, intent_cfg):
    return [p["name"] for p in intent_cfg["parameters"] if p["variable_name"] not in s.variables]

async def _handle_intent(s, intent_cfg, user_msg):
    missing = _missing(s, intent_cfg)
    if missing:
        p_prompt = build_parameter_prompt(intent_cfg, missing, user_msg, s.history)
        p_raw = await spark_generate(s, p_prompt, user_msg)
        if p_raw.startswith("#PARAMETERS:") and not _process_params(s, intent_cfg, p_raw):
            missing = _missing(s, intent_cfg)

    if missing:
        s.awaiting = {"intent": intent_cfg, "missing": missing}
        cap = next(p for p in intent_cfg["parameters"] if p["name"] == missing[0])["caption"]
        return f"{cap} nedir?"

    s.awaiting = None
    return await _call_api(s, intent_cfg)

async def _followup(s, user_msg):
    intent_cfg = s.awaiting["intent"]
    missing = s.awaiting["missing"]
    p_prompt = build_parameter_prompt(intent_cfg, missing, user_msg, s.history)
    p_raw = await spark_generate(s, p_prompt, user_msg)
    if not p_raw.startswith("#PARAMETERS:") or _process_params(s, intent_cfg, p_raw):
        return "Üzgünüm, anlayamadım."
    missing = _missing(s, intent_cfg)
    if missing:
        s.awaiting["missing"] = missing
        cap = next(p for p in intent_cfg["parameters"] if p["name"] == missing[0])["caption"]
        return f"{cap} nedir?"
    s.awaiting = None
    return await _call_api(s, intent_cfg)

def _process_params(s, intent_cfg, raw):
    try:
        data = json.loads(raw[len("#PARAMETERS:"):])
    except json.JSONDecodeError:
        return True
    for pair in data.get("extracted", []):
        p_cfg = next(p for p in intent_cfg["parameters"] if p["name"] == pair["name"])
        if not _valid(p_cfg, pair["value"]):
            return True
        s.variables[p_cfg["variable_name"]] = pair["value"]
    return False

def _valid(p_cfg, val):
    rx = p_cfg.get("validation_regex")
    return re.match(rx, val) is not None if rx else True

async def _call_api(s, intent_cfg):
    api = APIS[intent_cfg["action"]]
    token = "testtoken"
    headers = {k: v.replace("{{token}}", token) for k, v in api["headers"].items()}
    body = json.loads(json.dumps(api["body_template"]))
    for k, v in body.items():
        if isinstance(v, str) and v.startswith("{{") and v.endswith("}}"):
            body[k] = s.variables.get(v[2:-2], "")
    try:
        async with httpx.AsyncClient(timeout=api["timeout_seconds"]) as c:
            r = await c.request(api["method"], api["url"], headers=headers, json=body)
            r.raise_for_status()
            api_json = r.json()
    except Exception:
        return intent_cfg["fallback_error_prompt"]
    summary_prompt = api["response_prompt"].replace("{{api_response}}", json.dumps(api_json, ensure_ascii=False))
    return await spark_generate(s, summary_prompt, "")