"""domain 层：判定「该做什么」，不含 HTTP、不含 SQL。

这里集中三个最容易被写散的规则：
1. 文件 ↔ 项目 的匹配（精确，绝不猜）
2. 工单是否已存在 / 是否可续跑（幂等的判断源）
3. 版本推进（确认工单）的下一步参数
"""

from __future__ import annotations

import os
import zipfile
from dataclasses import dataclass
from enum import StrEnum

from .models import Project, WorkSheet, normalize_name


class Action(StrEnum):
    CREATE = "create"
    RESUME = "resume"
    SKIP_DONE = "skip-done"
    SKIP_EXISTS = "skip-exists"
    SKIP_PUSHED = "skip-pushed"
    ERROR = "error"

    @property
    def writes(self) -> bool:
        return self in {Action.CREATE, Action.RESUME}


@dataclass
class PlanRow:
    project_name: str
    file_path: str
    action: Action
    reason: str = ""
    project: Project | None = None
    worksheet: WorkSheet | None = None
    existing_count: int = 0


# 版本链（前端 EffortListVersionInfo 的等价物）
# version_code -> (next_operator, next_version_code, percent)；None 表示流程结束
VERSION_TRANSITIONS: dict[str, tuple[str, str, int] | None] = {
    "": ("CustomerLeader", "客户责任人确认版", 20),          # 新建草稿视同「技术责任人确认版」
    "技术责任人确认版": ("CustomerLeader", "客户责任人确认版", 20),
    "客户责任人确认版": ("CustomerLeader", "甲方确认版", 20),
    "甲方确认版": None,
}


def next_transition(version_code: str) -> tuple[str, str, int]:
    """返回 (NextOperator, NextVersionCode, Percent)。到终点则报错。"""
    if version_code not in VERSION_TRANSITIONS:
        raise ValueError(f"未知版本「{version_code}」，无法推导下一步")
    step = VERSION_TRANSITIONS[version_code]
    if step is None:
        raise ValueError(f"版本「{version_code}」已是流程终点，无需确认")
    return step


def decide(existing: list[WorkSheet], *, ledger_stage: str | None, adopt: bool) -> tuple[Action, str, WorkSheet | None]:
    """根据「服务器现状 + 台账记录」决定动作。"""
    if not existing:
        return Action.CREATE, "本项目该 Sprint 无工单", None

    # 优先看同一 Sprint 的工单（调用方已按 SystemName 过滤）
    worksheet = existing[0]
    if worksheet.done:
        return Action.SKIP_DONE, f"工单 {worksheet.code} 已确认完成（Status={worksheet.status}）", worksheet

    if ledger_stage == "TFS_PUSHED":
        return Action.SKIP_PUSHED, f"工单 {worksheet.code} 已推送 TFS", worksheet

    if ledger_stage:
        return Action.RESUME, f"台账记录停在 {ledger_stage}，续跑", worksheet

    if adopt:
        return Action.RESUME, "工单存在但无台账记录，--adopt 接管续跑", worksheet

    return Action.SKIP_EXISTS, f"工单 {worksheet.code} 已存在（无台账记录，未接管）", worksheet


def list_xlsx(folder: str) -> list[str]:
    if not os.path.isdir(folder):
        raise SystemExit(f"目录不存在：{folder}")
    result = []
    for name in sorted(os.listdir(folder)):
        path = os.path.join(folder, name)
        if os.path.isfile(path) and name.lower().endswith(".xlsx") and not name.startswith("~$"):
            result.append(path)
    return result


def match_project(stem: str, projects: list[Project]) -> tuple[Project | None, str]:
    """精确匹配项目；命中多个或零个都算失败，不做「包含即命中」的猜测。"""
    target = normalize_name(stem)
    exact = [p for p in projects if normalize_name(p.project_name) == target]
    if len(exact) == 1:
        return exact[0], ""
    if len(exact) > 1:
        names = "、".join(p.project_name for p in exact)
        return None, f"项目名歧义（{names}）"

    # 只用于提示，不给结果
    near = [p.project_name for p in projects if target in normalize_name(p.project_name)]
    hint = f"，相近项目：{'、'.join(near[:3])}" if near else ""
    return None, f"QuickTeam 中没有该项目{hint}"


def precheck_xlsx(path: str) -> tuple[bool, str]:
    """上传前的轻量自检：确认是「工作量评估表」模板，避免白跑一趟服务器解析。"""
    try:
        with zipfile.ZipFile(path) as archive:
            names = archive.namelist()
            if "xl/workbook.xml" not in names:
                return False, "不是 xlsx（缺少 xl/workbook.xml）"
            if "xl/sharedStrings.xml" not in names:
                return False, "文件为空表或已损坏"
            text = archive.read("xl/sharedStrings.xml").decode("utf-8", "ignore")
    except zipfile.BadZipFile:
        return False, "不是合法的 xlsx（可能仍是 Excel 打开中的临时文件）"
    except OSError as exc:
        return False, f"读取失败：{exc}"

    if "工作量评估表" not in text:
        return False, "未找到「工作量评估表」标题，可能不是工单模板"
    if "服务模块" not in text:
        return False, "未找到明细表头（服务模块），模板可能已变更"
    return True, ""