"""
UI 事件处理器 - 处理用户交互和输入验证
"""

import random
import re
import gradio as gr
from algorithm import build_payload


MAX_DEMO_LEN = 20


def parse_bits(text: str, name: str) -> list[int]:
    """
    解析二进制字符串输入
    允许 0/1，可以包含逗号和空格
    """
    cleaned = re.sub(r"[,\s]+", "", (text or "").strip())
    if not cleaned:
        raise gr.Error(f"{name} cannot be empty")
    if re.search(r"[^01]", cleaned):
        raise gr.Error(f"{name} must contain only 0/1 (spaces or commas allowed)")
    return [int(c) for c in cleaned]


def on_demo(
    q_text: str, k_text: str, v_text: str, line_numbers: dict
) -> tuple[str, str]:
    """
    处理演示按钮点击事件
    验证输入并生成步骤数据
    """
    q = parse_bits(q_text, "q")
    k = parse_bits(k_text, "k")
    v = parse_bits(v_text, "v")

    if not (len(q) == len(k) == len(v)):
        raise gr.Error("q, k, v must have the same length")
    if len(q) > MAX_DEMO_LEN:
        raise gr.Error(f"For smooth playback, length should be <= {MAX_DEMO_LEN}")

    return build_payload(q, k, v, line_numbers)


def on_random(length: int) -> tuple[str, str, str]:
    """
    生成随机的 q, k, v 序列
    用于演示目的
    """
    length = max(1, int(length))
    q = [random.randint(0, 1) for _ in range(length)]
    k = [random.randint(0, 1) for _ in range(length)]
    v = [random.randint(0, 1) for _ in range(length)]
    return (
        "".join(str(x) for x in q),
        "".join(str(x) for x in k),
        "".join(str(x) for x in v),
    )