"""确定性优先的任务规划；仅在无法分类页面时才请求可选 LLM。"""
from __future__ import annotations

import json
import os
import base64
import urllib.request
from dataclasses import dataclass

from .tools import REGISTRY


class PlanError(RuntimeError):
    pass


@dataclass(frozen=True)
class Step:
    tool: str
    arguments: dict
    reason: str


def classify(texts: list[str]) -> str:
    content = "\n".join(texts)
    if "证件号码后8位" in content or "请输入乘车人" in content:
        return "verify"
    if "发票信息确认" in content:
        return "invoice_confirm"
    if "发票开具成功" in content:
        return "success"
    if "发票信息" in content and ("提交" in content or "确认" in content):
        return "invoice_info"
    if "没有可开具电子发票" in content:
        return "no_ticket"
    if "开具" in content and "*" in content:
        return "list"
    return "unknown"


def deterministic_plan(task: dict) -> list[Step]:
    history = task.get("history", [])
    navigation = task.get("navigation", {})
    phase = navigation.get("phase")
    if phase in {"push_qr", "open_scan", "open_orders", "open_album", "select_qr", "wait_list"}:
        if phase not in {"push_qr", "wait_list"} and not task.get("allow_submit"):
            return []
        return [Step(f"nav.{phase}", {}, "进入扫码开票单列表")]
    if task.get("invoice", {}).get("finished"):
        return []
    if not history:
        return [Step("device.status", {}, "确认唯一目标设备"), Step("observe.screen", {}, "保存当前屏幕"), Step("observe.xml", {}, "读取可访问 UI 文本")]
    if history[-1].get("tool") not in {"observe.xml", "invoice.inspect"}:
        return [Step("observe.screen", {}, "动作后保存当前屏幕"), Step("observe.xml", {}, "动作后重新读取 UI 文本")]
    last = next((entry for entry in reversed(history) if entry.get("tool") == "observe.xml"), None)
    page = classify(last.get("result", {}).get("texts", [])) if last else "other"
    if page in {"other", "unknown"} and history[-1].get("tool") == "invoice.inspect":
        page = str(history[-1].get("result", {}).get("page", "other"))
        if page in {"other", "unknown"}:
            return []
    if page in {"other", "unknown"}:
        return [Step("invoice.inspect", {}, "XML 不足时由视觉识别页面")]
    if page == "loading":
        return [Step("invoice.wait", {"seconds": 2}, "等待开票网络请求完成")]
    if not task.get("allow_submit"):
        return []
    routes = {
        "list": ("invoice.open_next", "匹配名单并打开下一位乘客"),
        "verify": ("invoice.verify", "填写证件后八位并核验"),
        "invoice_info": ("invoice.submit_info", "提交发票信息"),
        "invoice_confirm": ("invoice.confirm", "确认开具"),
        "no_ticket": ("invoice.no_ticket", "记录无票并返回列表"),
    }
    if page == "success":
        action = task.get("invoice", {}).get("success_action", "download")
        return [Step("invoice.email", {}, "发送发票邮件并继续开票")] if action == "email" else [Step("invoice.download", {}, "下载发票、归档并继续开票")]
    if page in routes:
        tool, reason = routes[page]
        return [Step(tool, {}, reason)]
    return []


def validate_llm_steps(raw: object, *, allow_submit: bool) -> list[Step]:
    if not isinstance(raw, list):
        raise PlanError("LLM 返回必须是 steps 数组")
    if len(raw) > 3:
        raise PlanError("LLM 单次最多重规划 3 个原子工具")
    steps: list[Step] = []
    for item in raw:
        if not isinstance(item, dict):
            raise PlanError("LLM step 必须是对象")
        tool = item.get("tool")
        if tool not in REGISTRY:
            raise PlanError(f"LLM 请求了未注册工具：{tool}")
        if tool in {"ui.tap_normalized", "invoice.open_next", "invoice.verify", "invoice.submit_info", "invoice.confirm", "invoice.download", "invoice.email", "invoice.no_ticket", "nav.open_scan", "nav.open_orders", "nav.open_album", "nav.select_qr"} and not allow_submit:
            raise PlanError("默认禁止 LLM 直接点击业务按钮；请先在任务中显式启用 allow_submit")
        arguments = item.get("arguments", {})
        if not isinstance(arguments, dict):
            raise PlanError("工具参数必须是对象")
        steps.append(Step(tool, arguments, str(item.get("reason") or "LLM 重规划")))
    return steps


def llm_plan(task: dict, settings: dict) -> list[Step]:
    planner = settings.get("planner", {})
    if not planner.get("enabled"):
        return []
    base_url, model = str(planner.get("base_url", "")).rstrip("/"), str(planner.get("model", ""))
    api_key = os.environ.get(str(planner.get("api_key_env", "AUTOTRAIN_NEXT_LLM_API_KEY")), "")
    if not (base_url and model and api_key):
        raise PlanError("LLM 已启用但 base_url、model 或 API key 环境变量缺失")
    observations = [entry.get("result", {}) for entry in task.get("history", []) if entry.get("tool") == "observe.screen"]
    safe_task = {"type": task.get("type"), "allow_submit": bool(task.get("allow_submit")), "page": task.get("invoice", {}).get("page"), "recent_tools": [entry.get("tool") for entry in task.get("history", [])[-6:]]}
    content: list[dict] = [{"type": "text", "text": json.dumps({"task": safe_task, "tools": list(REGISTRY)}, ensure_ascii=False)}]
    if observations and observations[-1].get("screenshot"):
        try:
            image = open(observations[-1]["screenshot"], "rb").read()
            content.append({"type": "image_url", "image_url": {"url": "data:image/png;base64," + base64.b64encode(image).decode()}})
        except OSError:
            pass
    payload = {"model": model, "temperature": 0, "messages": [{"role": "system", "content": "你是手机自动化规划器。只返回 JSON：{\\\"steps\\\":[{\\\"tool\\\":...,\\\"arguments\\\":{},\\\"reason\\\":...}]}。不可编造工具。"}, {"role": "user", "content": content}]}
    request = urllib.request.Request(base_url + "/chat/completions", data=json.dumps(payload).encode(), headers={"Authorization": f"Bearer {api_key}", "Content-Type": "application/json"})
    with urllib.request.urlopen(request, timeout=45) as response:
        body = json.loads(response.read())
    content = body["choices"][0]["message"]["content"]
    parsed = json.loads(content)
    return validate_llm_steps(parsed.get("steps"), allow_submit=bool(task.get("allow_submit")))