"""HTTP client for a local Ollama generate API.

Matches the newsPipeline local_llm summarizer: POST /api/generate,
GET /api/tags. No API key. ``LLM_URL`` may be a host, ``/api``, or
``/api/generate`` — we normalize to the origin.
"""

from __future__ import annotations

import os

import httpx

_DEFAULT_UA = "osint-dashboard-news-summarizer"
_DEFAULT_BASE = "http://127.0.0.1:11434"
_GENERATE_TIMEOUT = 300.0
_TAGS_TIMEOUT = 8.0

_GENERATE_OPTIONS = {
    "num_predict": 4096,
    "temperature": 0.6,
    "top_p": 0.9,
    "top_k": 40,
    "num_ctx": 32768,
    "repeat_penalty": 1.1,
}


def normalize_base(url: str | None) -> str:
    """Strip path suffixes so LLM_URL variants share one origin."""
    raw = (url or os.environ.get("LLM_URL", "") or _DEFAULT_BASE).strip()
    raw = raw.rstrip("/")
    for suffix in ("/api/generate", "/api/chat", "/api", "/v1"):
        if raw.endswith(suffix):
            raw = raw[: -len(suffix)].rstrip("/")
            break
    return raw or _DEFAULT_BASE


def _headers() -> dict[str, str]:
    return {
        "User-Agent": os.environ.get("OSINT_USER_AGENT") or _DEFAULT_UA,
        "Accept": "application/json",
    }


def chat(prompt: str, *, model: str, base_url: str | None = None, json_mode: bool = False) -> str:
    """POST /api/generate. Returns response text, or \"\" on any failure."""
    if not (model or "").strip():
        return ""
    origin = normalize_base(base_url)
    url = f"{origin}/api/generate"
    payload: dict = {
        "model": model.strip(),
        "prompt": prompt,
        "stream": False,
        "options": dict(_GENERATE_OPTIONS),
    }
    if json_mode:
        payload["format"] = "json"
    try:
        with httpx.Client(timeout=_GENERATE_TIMEOUT) as client:
            resp = client.post(url, headers=_headers(), json=payload)
        if resp.status_code == 401 or resp.status_code >= 500:
            return ""
        data = resp.json()
        text = data.get("response") if isinstance(data, dict) else None
        return text if isinstance(text, str) else ""
    except Exception:
        return ""


def list_tags(base_url: str | None = None) -> list[str]:
    """GET /api/tags model names. Empty list on failure."""
    origin = normalize_base(base_url)
    url = f"{origin}/api/tags"
    try:
        with httpx.Client(timeout=_TAGS_TIMEOUT) as client:
            resp = client.get(url, headers=_headers())
        if resp.status_code != 200:
            return []
        models = (resp.json() or {}).get("models") or []
        names: list[str] = []
        for item in models:
            if isinstance(item, dict):
                name = item.get("name") or item.get("model") or ""
                if name:
                    names.append(str(name))
        return names
    except Exception:
        return []


def ollama_ready(model: str, *, base_url: str | None = None) -> bool:
    """True when /api/tags is up and ``model`` is present (prefix match)."""
    if not (model or "").strip():
        return False
    names = list_tags(base_url)
    if not names:
        return False
    want = model.strip()
    return any(n == want or n.startswith(want) for n in names)