from fastapi import APIRouter, Depends
from pydantic import BaseModel
from typing import List, Optional

from app.core.auth import get_current_user
from app.core.database import get_db_connection
from app.core.response import create_api_response

router = APIRouter()

# Pydantic Models
class PromptIn(BaseModel):
    name: str
    tags: Optional[str] = ""
    content: str

class PromptOut(PromptIn):
    id: int
    created_at: str

class PromptListResponse(BaseModel):
    prompts: List[PromptOut]
    total: int

@router.post("/prompts")
def create_prompt(prompt: PromptIn, current_user: dict = Depends(get_current_user)):
    """Create a new prompt."""
    with get_db_connection() as connection:
        cursor = connection.cursor(dictionary=True)
        try:
            cursor.execute(
                "INSERT INTO prompts (name, tags, content, creator_id) VALUES (%s, %s, %s, %s)",
                (prompt.name, prompt.tags, prompt.content, current_user["user_id"])
            )
            connection.commit()
            new_id = cursor.lastrowid
            return create_api_response(code="200", message="提示词创建成功", data={"id": new_id, **prompt.dict()})
        except Exception as e:
            if "UNIQUE constraint failed" in str(e) or "Duplicate entry" in str(e):
                return create_api_response(code="400", message="提示词名称已存在")
            return create_api_response(code="500", message=f"创建提示词失败: {e}")

@router.get("/prompts")
def get_prompts(page: int = 1, size: int = 12, current_user: dict = Depends(get_current_user)):
    """Get a paginated list of prompts filtered by current user."""
    with get_db_connection() as connection:
        cursor = connection.cursor(dictionary=True)
        # 只获取当前用户创建的提示词
        cursor.execute(
            "SELECT COUNT(*) as total FROM prompts WHERE creator_id = %s",
            (current_user["user_id"],)
        )
        total = cursor.fetchone()['total']

        offset = (page - 1) * size
        cursor.execute(
            "SELECT id, name, tags, content, created_at FROM prompts WHERE creator_id = %s ORDER BY created_at DESC LIMIT %s OFFSET %s",
            (current_user["user_id"], size, offset)
        )
        prompts = cursor.fetchall()
        return create_api_response(code="200", message="获取提示词列表成功", data={"prompts": prompts, "total": total})

@router.get("/prompts/{prompt_id}")
def get_prompt(prompt_id: int, current_user: dict = Depends(get_current_user)):
    """Get a single prompt by its ID."""
    with get_db_connection() as connection:
        cursor = connection.cursor(dictionary=True)
        cursor.execute("SELECT id, name, tags, content, created_at FROM prompts WHERE id = %s", (prompt_id,))
        prompt = cursor.fetchone()
        if not prompt:
            return create_api_response(code="404", message="提示词不存在")
        return create_api_response(code="200", message="获取提示词成功", data=prompt)

@router.put("/prompts/{prompt_id}")
def update_prompt(prompt_id: int, prompt: PromptIn, current_user: dict = Depends(get_current_user)):
    """Update an existing prompt."""
    with get_db_connection() as connection:
        cursor = connection.cursor(dictionary=True)
        try:
            cursor.execute(
                "UPDATE prompts SET name = %s, tags = %s, content = %s WHERE id = %s",
                (prompt.name, prompt.tags, prompt.content, prompt_id)
            )
            if cursor.rowcount == 0:
                return create_api_response(code="404", message="提示词不存在")
            connection.commit()
            return create_api_response(code="200", message="提示词更新成功")
        except Exception as e:
            if "UNIQUE constraint failed" in str(e) or "Duplicate entry" in str(e):
                return create_api_response(code="400", message="提示词名称已存在")
            return create_api_response(code="500", message=f"更新提示词失败: {e}")

@router.delete("/prompts/{prompt_id}")
def delete_prompt(prompt_id: int, current_user: dict = Depends(get_current_user)):
    """Delete a prompt. Only the creator can delete their own prompts."""
    with get_db_connection() as connection:
        cursor = connection.cursor(dictionary=True)
        # 首先检查提示词是否存在以及是否属于当前用户
        cursor.execute(
            "SELECT creator_id FROM prompts WHERE id = %s",
            (prompt_id,)
        )
        prompt = cursor.fetchone()

        if not prompt:
            return create_api_response(code="404", message="提示词不存在")

        if prompt['creator_id'] != current_user["user_id"]:
            return create_api_response(code="403", message="无权删除其他用户的提示词")

        # 删除提示词
        cursor.execute("DELETE FROM prompts WHERE id = %s", (prompt_id,))
        connection.commit()
        return create_api_response(code="200", message="提示词删除成功")