import { logger } from '@squeebot/core/lib/core';
import { IRepository } from '@squeebot/core/lib/plugin/repository';
import { ReadLine } from 'readline';
import { Squeebot } from './core';

declare type Executable = (...args: string[]) => Promise<any>;

class CLICommand {
  constructor(
    public name: string,
    public func: Executable,
    public sub: CLICommand[],
    public after?: (returned: any, ...args: string[]) => Promise<any>) {}

  public getSub(name: string): CLICommand | undefined {
    return this.sub.find(c => c.name.startsWith(name));
  }

  /**
   * Executes a sub-command or, if not found, the current one.
   * @param args Command arguments
   */
  public async execute(args: string[]): Promise<any> {
    if (args[0]) {
      const subl = this.getSub(args[0]);
      if (subl) {
        const rv1 = await subl.execute(args.slice(1));
        if (this.after) {
          return this.after.call(this, rv1, ...args);
        }
        return rv1;
      }
    }

    const rv2 = await this.func.call(this, ...args);
    if (this.after) {
      return this.after.call(this, rv2, ...args);
    }
    return rv2;
  }
}

function cmd(name: string, func: Executable, sub: CLICommand[] = []): CLICommand {
  return new CLICommand(name, func, sub);
}

export class SqueebotCLI {
  private inspector = false;
  private cmds: CLICommand[] = [
    // Repository management
    cmd('repository', async (...args: string[]): Promise<void> => {
      logger.log('Usage: repository add <url> | update <name> | remove <name> | plugins <name> | list');
    }, [
      cmd('install', async (...args: string[]): Promise<void> => {
        if (!args.length) {
          throw new Error('URL is required');
        }

        for (const urlp of args) {
          const repo = await this.bot.repositoryManager.installRepository(urlp);
          logger.log('Installed repository %s!', repo.name);
        }
      }),
      cmd('remove', async (...args: string[]): Promise<void> => {
        if (!args.length) {
          throw new Error('Name is required');
        }

        for (const namep of args) {
          await this.bot.repositoryManager.uninstallRepository(namep);
          logger.log('Installed repository %s.', namep);
        }
      }),
      cmd('update', async (...args: string[]): Promise<void> => {
        if (!args.length) {
          const repolist = this.bot.repositoryManager.getAll();
          for (const repo of repolist) {
            await this.checkUpdate(repo);
          }
          return;
        }

        for (const namep of args) {
          const repo = this.bot.repositoryManager.getRepoByName(namep);
          if (!repo) {
            throw new Error(`No such repository "${namep}" found.`);
          }

          await this.checkUpdate(repo);
        }
      }),
      cmd('plugins', async (...args: string[]): Promise<void> => {
        if (!args.length) {
          throw new Error('Name is required');
        }
        const repo = this.bot.repositoryManager.getRepoByName(args[0]);
        if (!repo) {
          throw new Error(`No such repository "${args[0]}" found.`);
        }
        logger.log('List of plugins in %s:', args[0],
          repo.plugins.map(x => `${x.name}@${x.version}`).join(', '));
      }),
      cmd('list', async (...args: string[]): Promise<void> => {
        const repos = this.bot.repositoryManager.getAll();
        logger.log('List of installed repositories:');
        for (const repo of repos) {
          logger.log('%s: (%s) with %d plugins | Date: %s',
            repo.name, repo.url, repo.plugins.length, new Date(repo.created * 1000).toDateString());
        }
      }),
    ]),
    // Plugin management
    cmd('plugin', async (...args: string[]): Promise<void> => {
      logger.log('Usage: plugin install | remove | enable | disable | load | restart | kill | list | running [<name>]');
    }, [
      cmd('install', async (...args: string[]): Promise<void> => {
        for (const name of args) {
          const mf = await this.bot.repositoryManager.installPlugin(name);
          logger.log('Installed plugin %s version %s!', mf.name, mf.version);
        }
      }),
      cmd('restart', async (...args: string[]): Promise<void> => {
        for (const name of args) {
          const plugin = this.bot.pluginManager.getAvailableByName(name);
          if (!plugin) {
            throw new Error(`"${name}" is not available. Maybe try installing it? plugin install ${name}`);
          }

          logger.log('Scheduling restart for', name);

          await this.bot.pluginManager.restart(plugin);
        }
      }),
      cmd('remove', async (...args: string[]): Promise<void> => {
        for (const name of args) {
          await this.bot.repositoryManager.uninstallPlugin(name);
          logger.log('Uninstalled plugin %s.', name);
        }
      }),
      cmd('running', async (...args: string[]): Promise<void> => {
        logger.log('Currently running plugins:',
          this.bot.pluginManager.getLoaded().map((p) => p.manifest.name).join(', '));
      }),
      cmd('load', async (...args: string[]): Promise<void> => {
        for (const name of args) {
          const plugin = this.bot.pluginManager.getAvailableByName(name);
          if (!plugin) {
            throw new Error(`"${name}" is not available. Maybe try installing it? plugin install`);
          }

          await this.bot.pluginManager.load(plugin);
          logger.log('Loaded plugin "%s" successfully.', name);
        }
      }),
      cmd('kill', async (...args: string[]): Promise<void> => {
        for (const name of args) {
          if (!this.bot.pluginManager.getAvailableByName(name)) {
            throw new Error('No such plugin is available.');
          }

          logger.log('Stopping plugin', name);

          this.bot.stream.emitTo(name, 'pluginUnload', name);
        }
      }),
      cmd('enable', async (...args: string[]): Promise<void> => {
        for (const name of args) {
          if (!this.bot.pluginManager.getAvailableByName(name)) {
            throw new Error(`No such plugin "${name}" found.`);
          }

          logger.log('Enabling plugin', name);

          if (!this.bot.config.config.enabled) {
            this.bot.config.config.enabled = [name];
            return;
          }

          if (this.bot.config.config.enabled.indexOf(name) === -1) {
            this.bot.config.config.enabled.push(name);
          }
        }

        await this.bot.config.save();
      }),
      cmd('disable', async (...args: string[]): Promise<void> => {
        for (const name of args) {
          if (!this.bot.config.config.enabled) {
            return;
          }

          logger.log('Disabling plugin', name);

          const indx = this.bot.config.config.enabled.indexOf(name);
          if (indx > -1) {
            this.bot.config.config.enabled.splice(indx, 1);
          }
        }

        await this.bot.config.save();
      }),
      cmd('list', async (...args: string[]): Promise<void> => {
        logger.log('Installed plugins:',
          this.bot.pluginManager.availablePlugins.map((mf) => mf.name).join(', '));
      }),
    ]),
    // Channel management, with an "after" handler
    new CLICommand('channel', async (...args: string[]): Promise<void> => {
      logger.log('Usage: channel new | del | list | addplugin | delplugin [<name>] [<plugin>]');
    }, [
      cmd('new', async (...args: string[]): Promise<void> => {
        if (this.bot.channelManager.getChannelByName(args[0])) {
          throw new Error('A channel by that name already exists!');
        }

        this.bot.channelManager.addChannel({
          name: args[0],
          plugins: [],
          enabled: true,
        });

        logger.log('Channel added!');
      }),
      cmd('remove', async (...args: string[]): Promise<void> => {
        for (const name of args) {
          const chan = this.bot.channelManager.getChannelByName(name);
          if (!chan) {
            throw new Error(`No such channel "${name}" found.`);
          }

          this.bot.channelManager.removeChannel(chan);

          logger.log('Channel "%s" removed!', name);
        }
      }),
      cmd('addplugin', async (...args: string[]): Promise<void> => {
        const chan1 = this.bot.channelManager.getChannelByName(args[0]);
        if (!chan1) {
          throw new Error('No such channel exists!');
        }

        if (!args[1]) {
          throw new Error('A plugin name is required.');
        }

        for (const name of args.slice(1)) {
          if (chan1.plugins.indexOf(name) === -1) {
            chan1.plugins.push(name);
          }

          logger.log('Plugin "%s" added to channel!', name);
        }
      }),
      cmd('delplugin', async (...args: string[]): Promise<void> => {
        const chan2 = this.bot.channelManager.getChannelByName(args[0]);
        if (!chan2) {
          throw new Error('No such channel exists!');
        }

        if (!args[1]) {
          throw new Error('A plugin name is required.');
        }

        for (const name of args.slice(1)) {
          const idx = chan2.plugins.indexOf(name);
          if (idx !== -1) {
            chan2.plugins.splice(idx, 1);
          }
          logger.log('Plugin "%s" removed from channel!', name);
        }
      }),
      cmd('enable', async (...args: string[]): Promise<void> => {
        for (const name of args) {
          const chan = this.bot.channelManager.getChannelByName(name);
          if (!chan) {
            throw new Error(`No such channel "${name}" found.`);
          }

          chan.enabled = true;
          logger.log('Channel "%s" enabled!', name);
        }
      }),
      cmd('disable', async (...args: string[]): Promise<void> => {
        for (const name of args) {
          const chan = this.bot.channelManager.getChannelByName(name);
          if (!chan) {
            throw new Error(`No such channel "${name}" found.`);
          }

          chan.enabled = false;
          logger.log('Channel "%s" disabled!', name);
        }
      }),
      cmd('list', async (...args: string[]): Promise<void> => {
        logger.log('Channels:\n', this.bot.channelManager.getAll().map((chan) => {
          return ` => ${chan.name}: ${chan.plugins.join(', ')} (${chan.enabled ? 'enabled' : 'disabled'})`;
        }).join('\n'));
      }),
    ], async (r: any, ...args: string[]): Promise<any> => {
      // Don't save when we just printed help or a list
      if (!args.length || 'list'.startsWith(args[0])) {
        return r;
      }
      // Save current channel configuration
      this.bot.config.config.channels = this.bot.channelManager.getAll();
      await this.bot.config.save();
      return r;
    }),
    // Enter inspector mode. Every line entered will be executed as JavaScript.
    cmd('inspector', async (...args: string[]): Promise<void> => {
      this.inspector = true;
      logger.warn('You have entered the JavaScript Inspector!');
      console.log('Squeebot is available via "sb" or "this.bot".');
      console.log('Type "exit" or "quit" to leave the inspector mode.');
    }),
    cmd('quit', async (...args: string[]): Promise<void> => this.bot.shutdown()),
  ];

  constructor(private bot: Squeebot) {}

  private getCommand(name: string): CLICommand | undefined {
    return this.cmds.find(c => c.name.startsWith(name));
  }

  private async checkUpdate(repo: IRepository): Promise<void> {
    const updatable = await this.bot.repositoryManager.checkForUpdates(repo);
    if (updatable.length) {
      logger.log('[%s] The following plugins can be updated:', repo.name,
        updatable.map((u) => u.name).join(', '));
    } else {
      logger.log('[%s] All plugins are up-to-date!', repo.name);
    }
  }

  private async sequentialExecute(cmds: string[][]): Promise<void> {
    for (const argv of cmds) {
      if (!argv[0]) {
        logger.log('Available CLI Commands:', this.cmds
          .map(c => `(${c.name.charAt(0)})${c.name.substring(1)}`)
          .join(', '));
        continue;
      }

      const clicmd = this.getCommand(argv[0]);
      if (!clicmd) {
        continue;
      }

      await clicmd.execute(argv.slice(1));
    }
  }

  public attach(rl: ReadLine): void {
    rl.on('line', (line: string) => {
      // Inspector mode
      if (this.inspector) {
        if (line.startsWith('exit') || line.startsWith('quit')) {
          this.inspector = false;
          logger.warn('You have exited the JavaScript Inspector!');
          return;
        }
        const sb = this.bot;
        try {
          // tslint:disable-next-line: no-eval
          console.log(eval(line));
        } catch (e: any) {
          console.error(e.stack);
        }
        return;
      }

      // Executing commands in order. If previous command fails, the rest won't execute.
      const executeList = line.split('&&');
      const toRun = executeList.map(subline => {
        return subline
          .replace(/\s+/g, ' ')
          .replace(/^\s+|\s+$/, '')
          .split(' ')
          .map(l => l.replace(',', ''));
      });

      this.sequentialExecute(toRun).catch(e => logger.error(e.message));
    });
  }
}