"""
ParamHub 工具函数
"""
import json
import base64
from pathlib import Path
from datetime import datetime
from werkzeug.utils import secure_filename

from config import (
    ALLOWED_EXTENSIONS, DEFAULT_CONFIG, CONFIG_FILE, IMAGES_DIR, DATA_DIR
)


def allowed_file(filename: str) -> bool:
    """检查文件扩展名是否允许"""
    return '.' in filename and filename.rsplit('.', 1)[1].lower() in ALLOWED_EXTENSIONS


def load_data(file_path: Path):
    """加载JSON数据文件"""
    if file_path.exists():
        return json.loads(file_path.read_text(encoding='utf-8'))
    return []


def save_data(file_path: Path, data):
    """保存JSON数据到文件"""
    file_path.write_text(json.dumps(data, ensure_ascii=False, indent=2), encoding='utf-8')


def load_config() -> dict:
    """加载网站配置，合并默认值"""
    if CONFIG_FILE.exists():
        loaded = json.loads(CONFIG_FILE.read_text(encoding='utf-8'))
        result = DEFAULT_CONFIG.copy()
        result.update(loaded)
        return result
    return DEFAULT_CONFIG.copy()


def save_config(config: dict):
    """保存网站配置"""
    CONFIG_FILE.write_text(json.dumps(config, ensure_ascii=False, indent=2), encoding='utf-8')


def get_items_file(category_id: str) -> Path:
    """获取动态分类的数据文件路径"""
    return DATA_DIR / f'items_{category_id}.json'


def get_llm_config() -> dict:
    """从 config.json 动态读取 LLM 配置"""
    config = load_config()
    return {
        'base_url': config.get('llm_base_url', DEFAULT_CONFIG['llm_base_url']),
        'api_key': config.get('llm_api_key', DEFAULT_CONFIG['llm_api_key']),
        'model': config.get('llm_model', DEFAULT_CONFIG['llm_model']),
        'vision_model': config.get('llm_vision_model', DEFAULT_CONFIG['llm_vision_model']),
    }


def parse_date_to_timestamp(date_str: str) -> float | None:
    """将日期字符串转换为 Unix 时间戳"""
    if not date_str:
        return None
    for fmt in ['%Y-%m-%d', '%Y-%m-%d %H:%M:%S', '%Y/%m/%d']:
        try:
            return datetime.strptime(date_str, fmt).timestamp()
        except (ValueError, TypeError):
            pass
    return None


def safe_sort_key(x: dict, key: str):
    """排序时安全获取字段值，缺失时返回合理默认值"""
    val = x.get(key)
    if val is None:
        if key in ['parameters', 'context_length', 'mmlu', 'views']:
            return 0
        elif key in ['publish_date', 'created_at', 'updated_at']:
            return ''
        return ''
    return val


def read_image_base64(img_src: str) -> str | None:
    """将图片路径/base64/URL转换为base64 data URI"""
    import base64 as b64
    if img_src.startswith('data:'):
        return img_src
    if img_src.startswith('http'):
        return img_src  # URL 直接传给 LLM
    # 本地路径
    try:
        img_path = IMAGES_DIR / img_src.replace('/static/uploads/', '')
        if img_path.exists():
            with open(img_path, 'rb') as f:
                img_data = b64.b64encode(f.read()).decode()
            ext = img_path.suffix.lower().lstrip('.')
            mime = f'image/{"jpeg" if ext == "jpg" else ext}'
            return f'data:{mime};base64,{img_data}'
    except Exception:
        pass
    return None