import os
import json
import time
import uuid
import re
from flask import render_template, request, url_for

from common.logger import system_logger

STORE_FILE = os.path.join(
    os.path.dirname(__file__),
    "temp_text_store.json"
)

EXPIRE_SECONDS = 3600  # 1小时


# =========================
# load
# =========================
def load_store():
    if not os.path.exists(STORE_FILE):
        return {}

    try:
        with open(STORE_FILE, "r", encoding="utf-8") as f:
            return json.load(f)
    except:
        return {}


# =========================
# save
# =========================
def save_store(data):
    with open(STORE_FILE, "w", encoding="utf-8") as f:
        json.dump(data, f, ensure_ascii=False, indent=2)


# =========================
# markdown轻量格式化（V2新增）
# =========================
def normalize_markdown(text: str) -> str:

    if not text:
        return ""

    text = text.replace("\r\n", "\n").replace("\r", "\n")

    # 去掉多余空行（最多保留1个空行）
    text = re.sub(r"\n{3,}", "\n\n", text)

    # 行首尾空格清理
    lines = [line.rstrip() for line in text.split("\n")]

    return "\n".join(lines).strip()


# =========================
# cleanup
# =========================
def cleanup(store):
    now = time.time()

    expired = [
        k for k, v in store.items()
        if v["expires_at"] < now
    ]

    for k in expired:
        del store[k]

    return store


# =========================
# 创建页面
# =========================
def temp_text_create_page():

    message = None
    share_link = None

    if request.method == "POST":

        content = request.form.get("content", "")

        if not content.strip():
            return render_template("temp_text.html", message="内容不能为空")

        # ✔ markdown规范化
        content = normalize_markdown(content)

        store = load_store()
        store = cleanup(store)

        text_id = uuid.uuid4().hex[:8]
        now = time.time()

        store[text_id] = {
            "content": content,
            "created_at": now,
            "expires_at": now + EXPIRE_SECONDS
        }

        save_store(store)

        share_link = url_for("temp_text_view_route", text_id=text_id, _external=True)

        system_logger.info(f"[TempTextV2] create id={text_id}")

        message = "创建成功（1小时有效）"

    return render_template(
        "temp_text.html",
        message=message,
        share_link=share_link
    )


# =========================
# 查看页面
# =========================
def temp_text_view(text_id):

    store = load_store()
    store = cleanup(store)

    if text_id not in store:
        return "内容不存在或已过期"

    content = store[text_id]["content"]

    system_logger.info(f"[TempTextV2] view id={text_id}")

    return render_template(
        "temp_text_view.html",
        content=content,
        text_id=text_id
    )