from fastapi import APIRouter, HTTPException, Depends
from pydantic import BaseModel
from typing import Optional
import auth
import issue_db

router = APIRouter()

class IssueCreate(BaseModel):
    title: str
    type: str = "bug"
    description: str
    markdown_sample: str = ""

class ReplyCreate(BaseModel):
    content: str

class StatusUpdate(BaseModel):
    status: str

# ==================== 用户接口 ====================

@router.post("/api/issues")
def create_issue(data: IssueCreate, current_user: dict = Depends(auth.get_current_user)):
    """用户提交新 Issue"""
    if not data.title or not data.title.strip():
        raise HTTPException(status_code=400, detail="标题不能为空")
    if not data.description or not data.description.strip():
        raise HTTPException(status_code=400, detail="描述不能为空")
    if data.type not in ("bug", "feature", "other"):
        raise HTTPException(status_code=400, detail="类型无效，请选择 bug / feature / other")

    new_issue = issue_db.create_issue(
        user_id=current_user["id"],
        username=current_user["username"],
        title=data.title.strip(),
        issue_type=data.type,
        description=data.description.strip(),
        markdown_sample=data.markdown_sample
    )
    return {"message": "Issue 已提交", "issue": new_issue}

@router.get("/api/issues/my")
def get_my_issues(current_user: dict = Depends(auth.get_current_user)):
    """获取当前用户提交的 Issue 列表"""
    issues = issue_db.get_user_issues(current_user["id"])
    return {"issues": issues}

@router.get("/api/issues/{issue_id}")
def get_issue_detail(issue_id: int, current_user: dict = Depends(auth.get_current_user)):
    """获取单条 Issue 详情（用户只能查看自己的，admin 可以查看所有）"""
    issue = issue_db.get_issue_by_id(issue_id)
    if not issue:
        raise HTTPException(status_code=404, detail="Issue 不存在")
    # 权限校验：只有 Issue 提交者或 admin 可以查看
    if issue["user_id"] != current_user["id"] and current_user["username"] != "admin":
        raise HTTPException(status_code=403, detail="无权查看此 Issue")
    return {"issue": issue}

@router.post("/api/issues/{issue_id}/reply")
def user_reply_issue(issue_id: int, data: ReplyCreate, current_user: dict = Depends(auth.get_current_user)):
    """用户对自己的 Issue 追加回复"""
    if not data.content or not data.content.strip():
        raise HTTPException(status_code=400, detail="回复内容不能为空")

    issue = issue_db.get_issue_by_id(issue_id)
    if not issue:
        raise HTTPException(status_code=404, detail="Issue 不存在")
    if issue["user_id"] != current_user["id"] and current_user["username"] != "admin":
        raise HTTPException(status_code=403, detail="无权回复此 Issue")

    reply = issue_db.add_reply(issue_id, current_user["username"], data.content.strip())
    if not reply:
        raise HTTPException(status_code=500, detail="回复失败")
    return {"message": "回复成功", "reply": reply}

# ==================== 管理员接口 ====================

@router.get("/api/admin/issues")
def admin_get_all_issues(current_user: dict = Depends(auth.get_current_user)):
    """管理员获取所有 Issue"""
    if current_user["username"] != "admin":
        raise HTTPException(status_code=403, detail="无权访问，需要管理员权限")
    issues = issue_db.get_all_issues()
    return {"issues": issues, "total": len(issues)}

@router.post("/api/admin/issues/{issue_id}/reply")
def admin_reply_issue(issue_id: int, data: ReplyCreate, current_user: dict = Depends(auth.get_current_user)):
    """管理员回复 Issue"""
    if current_user["username"] != "admin":
        raise HTTPException(status_code=403, detail="无权访问")
    if not data.content or not data.content.strip():
        raise HTTPException(status_code=400, detail="回复内容不能为空")

    issue = issue_db.get_issue_by_id(issue_id)
    if not issue:
        raise HTTPException(status_code=404, detail="Issue 不存在")

    reply = issue_db.add_reply(issue_id, "admin", data.content.strip())
    if not reply:
        raise HTTPException(status_code=500, detail="回复失败")
    return {"message": "回复成功", "reply": reply}

@router.put("/api/admin/issues/{issue_id}/status")
def admin_update_status(issue_id: int, data: StatusUpdate, current_user: dict = Depends(auth.get_current_user)):
    """管理员更新 Issue 状态"""
    if current_user["username"] != "admin":
        raise HTTPException(status_code=403, detail="无权访问")
    if data.status not in ("open", "in_progress", "closed"):
        raise HTTPException(status_code=400, detail="状态无效，请选择 open / in_progress / closed")

    issue = issue_db.update_issue_status(issue_id, data.status)
    if not issue:
        raise HTTPException(status_code=404, detail="Issue 不存在")
    return {"message": "状态更新成功", "issue": issue}