import {Logger, LoggingLevel, LogMessage} from "@extollo/util";
import {Singleton} from "@extollo/di";

@Singleton()
export class Logging {
    protected registeredLoggers: Logger[] = []
    protected currentLevel: LoggingLevel = LoggingLevel.Warning

    public registerLogger(logger: Logger) {
        if ( !this.registeredLoggers.includes(logger) ) {
            this.registeredLoggers.push(logger)
        }
    }

    public unregisterLogger(logger: Logger) {
        this.registeredLoggers = this.registeredLoggers.filter(x => x !== logger)
    }

    public get level(): LoggingLevel {
        return this.currentLevel
    }

    public set level(level: LoggingLevel) {
        this.currentLevel = level
    }

    public success(output: any, force = false) {
        this.writeLog(LoggingLevel.Success, output, force)
    }

    public error(output: any, force = false) {
        this.writeLog(LoggingLevel.Error, output, force)
    }

    public warn(output: any, force = false) {
        this.writeLog(LoggingLevel.Warning, output, force)
    }

    public info(output: any, force = false) {
        this.writeLog(LoggingLevel.Info, output, force)
    }

    public debug(output: any, force = false) {
        this.writeLog(LoggingLevel.Debug, output, force)
    }

    public verbose(output: any, force = false) {
        this.writeLog(LoggingLevel.Verbose, output, force)
    }

    protected writeLog(level: LoggingLevel, output: any, force = false) {
        const message = this.buildMessage(level, output)
        if ( this.currentLevel >= level || force ) {
            for ( const logger of this.registeredLoggers ) {
                try {
                    logger.write(message)
                } catch (e) {
                    console.error('logging error', e)
                }
            }
        }
    }

    protected buildMessage(level: LoggingLevel, output: any): LogMessage {
        return {
            level,
            output,
            date: new Date,
            callerName: this.getCallerInfo(),
        }
    }

    protected getCallerInfo(level = 5): string {
        const e = new Error()
        if ( !e.stack ) return 'Unknown'

        return e.stack.split(/\s+at\s+/)
            .slice(level)
            .map((x: string): string => x.trim().split(' (')[0].split('.')[0].split(':')[0])[0]
            .split('/')
            .reverse()[0]
    }
}