import * as os from "os";
import * as fs from "fs";
import * as path from "path";
import * as _ from "lodash";
import * as yaml from "js-yaml";
import { ReportLaunchingCircuitBreaker } from "./Reporting/ReportLaunchingCircuitBreaker";
import { Reporter } from "./Core/Reporter";

export interface Config {
  reporters: (string | Reporter)[];
  normalizeLineEndingsTo: boolean | string;
  failOnLineEndingDifferences: boolean;
  appendEOL: boolean;
  EOL: string;
  errorOnStaleApprovedFiles: boolean;
  shouldIgnoreStaleApprovedFile: (fileName?: string) => boolean;
  stripBOM: boolean;
  forceApproveAll: boolean;
  blockUntilReporterExits: boolean;
  maxLaunches: number;
  cmdOptionOverrides?: any;
  cmdArgs?: string[];
}

// begin-snippet: default_config
export const defaultConfig: Config = {
  reporters: [
    "BeyondCompare",
    "diffmerge",
    "p4merge",
    "tortoisemerge",
    "nodediff",
    "opendiff",
    "gitdiff",
  ],
  normalizeLineEndingsTo: false,
  failOnLineEndingDifferences: false,
  appendEOL: true,
  EOL: os.EOL,
  errorOnStaleApprovedFiles: true,
  shouldIgnoreStaleApprovedFile: () => false,
  stripBOM: false,
  forceApproveAll: false,
  blockUntilReporterExits: false,
  maxLaunches: 10,
};
// end-snippet

export function getHomeApprovalConfig(): Config | null {
  const homeConfigPath = path.join(os.homedir(), ".approvalsConfig");
  if (fs.existsSync(homeConfigPath)) {
    const configFileData = fs.readFileSync(homeConfigPath).toString();
    try {
      return yaml.load(configFileData) as Config;
    } catch (ex) {
      throw new Error("Error parsing " + homeConfigPath + ". " + ex);
    }
  }
  return null;
}

let currentConfigObj: Config;

export function getConfig(configOverrides?: Partial<Config>): Config {
  const homeConfig = getHomeApprovalConfig() || {};
  const resultConfig = _.defaults(
    configOverrides || {},
    currentConfigObj || {},
    homeConfig,
    defaultConfig,
  );
  return resultConfig as Config;
}

export function configure(overrideOptions?: Partial<Config>): Config {
  currentConfigObj = getConfig(overrideOptions);
  processConfig(currentConfigObj);
  return currentConfigObj;
}

export function currentConfig(): Config {
  return currentConfigObj;
}

export function reset(): void {
  currentConfigObj = _.defaults({}, getHomeApprovalConfig(), defaultConfig);
}

currentConfigObj = getConfig();

function processConfig(config: Config): void {
  if (config.maxLaunches) {
    ReportLaunchingCircuitBreaker.setMaxLaunch(config.maxLaunches);
  }
}