import chalk from 'chalk';
import {execSync} from 'child_process';
import {DotenvParseOutput} from 'dotenv';
import {defaultValue, flag, help, param} from 'oo-cli';
import {AppContext, appContext} from '../../lib/AppContext';
import {AppPackager} from '../../lib/AppPackager';
import {AppUpdater} from '../../lib/AppUpdater';
import {AppUploader} from '../../lib/AppUploader';
import {die} from '../../lib/die';
import {directoryExists} from '../../lib/directoryExists';
import {formatBuildState} from '../../lib/formatBuildState';
import {gatherAppEnv, validateAppEnvs} from '../../lib/gatherAppEnv';
import {handleInterrupt} from '../../lib/handleInterrupt';
import {TerminalSpinner} from '../../lib/TerminalSpinner';
import {ErrorList, watchBuild} from '../../lib/build';
import {Rivendell} from '../../lib/Rivendell';
import {formatError} from '../../lib/formatError';
import {RivendellApi} from '../../lib/RivendellApi';
import {applicableShards, targetShards} from '../../lib/Shards';
import ApiError = RivendellApi.ApiError;
import Build = Rivendell.Build;
import BuildState = Rivendell.BuildState;
import AppVersion = Rivendell.AppVersion;
import AppVersionState = Rivendell.AppVersionState;
import ReviewStatus = Rivendell.ReviewStatus;

export abstract class BaseBuildCommand {
  @flag('no-progress')
  @help("Don't display any progress indicators")
  public noProgress!: boolean;

  @flag('upgrade-deps')
  @help('Automatically update dependencies')
  public upgradeDeps!: boolean;

  @param
  @help('The root directory of the app')
  @defaultValue('./')
  public path!: string;

  protected async run(upload: boolean, publish: boolean, usePreviousAppEnvValues: boolean) {
    handleInterrupt();

    if (!directoryExists(this.path)) {
      die('Specified path to app does not exist');
    }
    process.chdir(this.path);

    const context = appContext();
    if (!context.appId || !context.version || !context.runtime) {
      die('Unable to read App ID or version info. Ensure you are uploading the right directory.');
      return;
    }

    if (!usePreviousAppEnvValues) {
      validateAppEnvs(await targetShards());
    }
    const shards: string[] = await applicableShards();

    await AppUpdater.ensureDependencies(upload, this.upgradeDeps, context.runtime);

    console.log(chalk.gray('Performing local validation...'));
    try {
      execSync('yarn --silent validate', {stdio: 'inherit'});
    } catch (e) {
      process.exit(1);
    }
    if (upload) {
      console.log(chalk.gray('Verifying upload constraints...'));
      try {
        execSync('git rev-parse --is-inside-work-tree');
      } catch (e) {
        console.log(chalk.red('\nApp must be in an initialized Git repository'));
        process.exit(1);
      }

      try {
        const version = await this.fetchAppVersion(context, 'us');
        const packageUrl = version?.state === AppVersionState.RUNNING
          ? version?.packageUrl
          : await this.uploadPackage(context);

        for (const shard of shards) {
          let appEnv = gatherAppEnv(shard);
          if (usePreviousAppEnvValues && Object.keys(appEnv).length > 0) {
            console.log(chalk.yellow('\n--use-previous-app-env-values is on. Ignoring values from .env file'));
            appEnv = {};
          }
          await this.registerOrUpdateVersion(context, packageUrl, appEnv, usePreviousAppEnvValues, shard);
        }

        if (version?.state !== AppVersionState.RUNNING) {
          await this.build(context, publish);
        }
      } catch (e) {
        die(formatError(e));
      }
    }
  }

  protected async fetchAppVersion(context: AppContext, shard: string): Promise<AppVersion | null> {
    try {
      return await Rivendell.fetchAppVersion(context, shard);
    } catch (e) {
      if (e instanceof ApiError && e.response?.status === 404) {
        console.log(chalk.gray('Existing version not found...'));
        return null;
      }

      throw e;
    }
  }

  protected isRelease(appVersionId: string) {
    return !this.isDevVersion(appVersionId);
  }

  protected isDevVersion(appVersionId?: string) {
    return appVersionId?.includes('-dev');
  }

  protected async reviewAppVersion(appId: string, version: string) {
     if (await this.requiresReview(version)) {
       const appVersion = await this.fetchAppVersion({appId, version}, 'us');
       if (appVersion?.state === AppVersionState.PUBLISHED && appVersion.reviewStatus !== ReviewStatus.NOT_REQUIRED) {
         await Rivendell.reviewAppVersion(appId, version);
       }
     }
  }

  protected async isInReview(appId: string, version: string) {
      const appVersion = await this.fetchAppVersion({appId, version}, 'us');
      if (appVersion) {
        const reviewStatus = appVersion.reviewStatus as ReviewStatus;
        return reviewStatus === ReviewStatus.IN_REVIEW;
      } else {
        return false;
      }
  }

  protected async requiresReview(version: string) {
    return !await this.isAdmin() && this.isRelease(version);
  }

  private async uploadPackage(context: AppContext): Promise<string> {
    try {
      await Rivendell.fetchApp(context.appId!);
      const packageData = new AppPackager('./').package();
      return await new AppUploader(context, packageData).upload();
    } catch (e) {
      console.log('App ID must be registered before it can be uploaded. Try:');
      console.log('  opti app register');
      throw e;
    }
  }

  private async build(context: AppContext, publish: boolean) {
    try {
      const build = await this.startBuild(context, publish);
      await this.watchForBuildCompletion(context, build.id, publish);
    } catch (e) {
      console.log('App ID must be registered before it can be uploaded. Try:');
      console.log('  opti app register');
      throw e;
    }
  }

  private async registerOrUpdateVersion(
    context: AppContext,
    packageUrl: string,
    appEnv: DotenvParseOutput,
    usePreviousAppEnvValues: boolean,
    shard: string)
  : Promise<void> {
    try {
      console.log(chalk.gray(`Checking for existing version (${shard})...`));
      const version = await this.fetchAppVersion(context, shard);
      if (version?.state === AppVersionState.RUNNING) {
        console.log(`AppVersion already running (${shard})`);
      } else if (version) {
        await this.updateVersion(context, packageUrl, appEnv, usePreviousAppEnvValues, shard);
      } else {
        await this.registerVersion(context, packageUrl, appEnv, usePreviousAppEnvValues, shard);
      }
    } catch (e) {
      die(`${formatError(e)} (${shard})`);
    }
  }

  private async registerVersion(
    context: AppContext,
    packageUrl: string,
    appEnv: DotenvParseOutput,
    usePreviousAppEnvValues: boolean,
    shard: string
  ): Promise<void> {
    console.log(chalk.gray(`Registering a new version (${shard})...`));
    await Rivendell.registerAppVersion(
      context.appId!!,
      context.version!!,
      packageUrl,
      appEnv,
      usePreviousAppEnvValues,
      shard
    );
  }

  private async updateVersion(
    context: AppContext,
    packageUrl: string,
    appEnv: DotenvParseOutput,
    usePreviousAppEnvValues: boolean,
    shard: string)
  : Promise<void> {
    console.log(chalk.gray(`Updating existing version (${shard})...`));
    await Rivendell.updateAppVersion(
      context.appId!!,
      context.version!!,
      packageUrl,
      appEnv,
      usePreviousAppEnvValues,
      shard
    );
  }

  private async startBuild(context: AppContext, publish: boolean): Promise<Build> {
    console.log(chalk.gray(`Starting ${publish ? 'build' : 'validation '}...`));
    return publish
      ? await Rivendell.build(context.appId!, context.version!)
      : await Rivendell.verify(context.appId!, context.version!);
  }

  private async watchForBuildCompletion(context: AppContext, id: number, publish: boolean) {
    console.log(
      chalk.gray(`Waiting for ${publish ? 'build' : 'validation'} (id=${id}) to complete... CTRL+C to stop checking.`)
    );

    const spinner = this.noProgress ? null :
      new TerminalSpinner().start(`Status: ${formatBuildState(BuildState.NEW)}`);
    const requiresReview = await this.requiresReview(context.version as string);

    return watchBuild(id, (state) => {
      spinner?.update(`Status: ${formatBuildState(state)}`);
    }).then((errors: ErrorList) => {
      spinner?.stop();
      if (errors) {
        die(`${publish ? 'Build' : 'Validation'} failed:\n${errors.map((e) => ` * ${e}`).join('\n')}`);
      } else if (publish) {
        if (requiresReview) {
          console.log(chalk.green('Build complete.'));
        } else {
          console.log(chalk.green('Build complete. Ready to be published.'));
        }
      } else {
        console.log(chalk.green('Validation complete. No errors found.'));
      }
    }).catch((err) => {
      die(formatError(err));
    });
  }

  private async isAdmin() {
    const me = await Rivendell.whoami();
    return me.role === 'administrator' || me.role === 'app_administrator';
  }
}