import {
  CommandInteraction, 
  TextChannel,
  SlashCommandBuilder,
  SlashCommandBooleanOption,
  CommandInteractionOptionResolver,
} from 'discord.js';
import {writeFileSync} from 'fs';

import {Command} from '../../classes/command';
import {logger} from '../../logger';
import {config} from '../../config';
import {getContest, getProblem, getSession} from '../../functions/database';

function isTextChannel(data: unknown): data is TextChannel{
  return (data as TextChannel).name !== undefined;
}

type CIOR = CommandInteractionOptionResolver;

class Result extends Command{
  get name(){return "result";}
  get description(){return "See the result of a contest.";}
  async execute(interaction: CommandInteraction): Promise<void>{
    if(!isTextChannel(interaction.channel)){
      await interaction.reply({
        content: `Channel name doesn't exist!`
      });
      logger.error(`Channel name doesn't exist`);
      return;
    }
    const contestName = interaction.channel.name;
    const channelId = interaction.channel.id;
    const markdown = (interaction.options as CIOR).getBoolean('markdown') ?? false;
    const contest = await getContest(channelId);
    if(contest === null){
      await interaction.reply({
        content: `The contest in this channel didn't start!`
      });
      logger.error(`Contest ${contestName} didn't start`);
      return;
    }
    let content: string = '';
    content += `# ${contestName}\n\n`
    contest.problems.sort(
      (a, b) => {
        if(a.problemId > b.problemId)
          return 1;
        if(a.problemId < b.problemId)
          return -1;
        return 0;
      }
    );
    const getTime = (time: number) => {
      if(time === -1) return -1;
      return Math.floor((time-contest.startTime)/(1000*60));
    };
    for(const problem of contest.problems){
      const p = await getProblem(problem._id);
      if(p === null) continue;
      content += `## p${p.problemId}\n`;
      if(getTime(p.ac) === -1)
        content += "*Problem unsolved!*\n";
      else
        content += `**AC** at ${getTime(p.ac)} min\n`;
      if(p.wa.length !== 0){
        content += `**WA** at`;
        let isFirst: boolean = true;
        for(const wa of p.wa.sort()){
          if(isFirst) isFirst = false;
          else content += ',';
          content += ` ${getTime(wa)}`;
        }
        content += ' min\n';
      }
      if(p.read.length === 0)
        content += "*Problem unread!*\n";
      else{
        content += `**Read**:\n`;
        for(const session of p.read){
          const s = await getSession(session._id);
          if(s === null) continue;
          content += `- \`${s.name}\` at ${getTime(s.start)} min`;
          if(getTime(s.end) !== -1)
            content += ` (estimate: ${getTime(s.end)} min)`;
          content += '\n';
        }
      }
      if(p.code.length === 0)
        content += "*No one have attempted*\n";
      else{
        content += `**Code**:\n`;
        for(const session of p.code){
          const s = await getSession(session._id);
          if(s === null) continue;
          content += `- \`${s.name}\` at ${getTime(s.start)} min`
          content += ` (estimate: ${getTime(s.end)} min)\n`;
        }
      }
      content += '\n';
    }
    if(markdown){
      const file = `${config.mdBaseDir}/${channelId}.md`;
      logger.log(`Output to ${file}`);
      await writeFileSync(file, content, {encoding: 'utf8'});
      await interaction.reply({files:[file]});
    }else
      await interaction.reply({content: content});
    logger.log(`Command: result of ${contestName}/${channelId}`);
  }
  override build(): SlashCommandBuilder | 
    Omit<SlashCommandBuilder, "addSubcommand" | "addSubcommandGroup">{
    return new SlashCommandBuilder()
      .setName(this.name)
      .setDescription(this.description)
      .addBooleanOption((option: SlashCommandBooleanOption) =>
        option
          .setName('markdown')
          .setDescription('If true then upload markdown file instead.')
        )
  }
};

export const command = new Result();