import os
import yaml

CONFIG_PATH = os.path.expanduser('~/.claude/autoresearch.yaml')
DEFAULTS = {'time_limit_minutes': 10, 'benchmarks': []}

class ConfigError(Exception):
    pass

def load_config(path=CONFIG_PATH):
    with open(path) as f:
        cfg = yaml.safe_load(f)
    if not cfg or 'projects' not in cfg or not cfg['projects']:
        raise ConfigError(f"'projects' list is required in {path}")
    for p in cfg['projects']:
        p.setdefault('benchmarks', DEFAULTS['benchmarks'])
        p.setdefault('time_limit_minutes', DEFAULTS['time_limit_minutes'])
        p['path'] = os.path.expanduser(p['path'])
    cfg.setdefault('token_threshold', {'context_remaining_pct': 60, 'api_budget_usd': 5.0})
    return cfg