import type { LogLevel } from './types.js';

export function getEnv(name: string, defaultValue?: string): string | undefined {
    return process.env[name] || defaultValue;
}

export function getLogLevel(prefix?: string): LogLevel {
    const envName = prefix ? `${prefix}_LOG_LEVEL` : 'LOG_LEVEL';
    const val = getEnv(envName, 'info') as LogLevel;
    const validLevels: LogLevel[] = ['verbose', 'debug', 'info', 'warn', 'error'];
    return validLevels.includes(val) ? val : 'info';
}

export function getThrowError(prefix?: string): boolean {
    const envName = prefix ? `${prefix}_THROW_ERROR` : 'THROW_ERROR';
    const val = getEnv(envName);
    if (val === undefined) return true;
    return val.toLowerCase() === 'true';
}

export function matchesDebug(namespace: string): boolean {
    const debugEnv = getEnv('DEBUG');
    if (!debugEnv) return false;

    const patterns = debugEnv.split(',').map(p => p.trim());
    for (const pattern of patterns) {
        if (pattern === '*') return true;
        const regex = new RegExp('^' + pattern.replace(/\*/g, '.*') + '$');
        if (regex.test(namespace)) return true;
    }

    return false;
}

export const LevelSeverity: Record<LogLevel, number> = {
    verbose: 0,
    debug: 1,
    info: 2,
    warn: 3,
    error: 4,
};

export function shouldLog(level: LogLevel, threshold: LogLevel, namespace?: string): boolean {
    if (LevelSeverity[level] >= LevelSeverity[threshold]) {
        return true;
    }

    if ((level === 'verbose' || level === 'debug') && namespace && matchesDebug(namespace)) {
        return true;
    }

    return false;
}