import { prefixCache, disabledCmdCache, disabledCache, commands, messageCommands } from "../collections.js";
import * as logger from "../logger.js";

import Postgres from "postgres";
const sql = Postgres(process.env.DB);

const psqlUpdates = [
  "", // reserved
  "CREATE TABLE IF NOT EXISTS settings ( id smallint PRIMARY KEY, version integer NOT NULL, CHECK(id = 1) );\nALTER TABLE guilds ADD COLUMN accessed timestamp;",
  "ALTER TABLE guilds DROP COLUMN accessed"
];

export async function setup() {
  let counts;
  try {
    counts = await sql`SELECT * FROM counts`;
  } catch {
    counts = [];
  }

  const merged = new Map([...commands, ...messageCommands]);

  if (!counts.length) {
    for (const command of merged.keys()) {
      await sql`INSERT INTO counts ${sql({ command, count: 0 }, "command", "count")}`;
    }
  } else {
    const exists = [];
    for (const command of merged.keys()) {
      const count = await sql`SELECT * FROM counts WHERE command = ${command}`;
      if (!count.length) {
        await sql`INSERT INTO counts ${sql({ command, count: 0 }, "command", "count")}`;
      }
      exists.push(command);
    }

    for (const { command } of counts) {
      if (!exists.includes(command)) {
        await sql`DELETE FROM counts WHERE command = ${command}`;
      }
    }
  }
}

export async function upgrade(logger) {
  let version;
  try {
    version = (await sql`SELECT version FROM settings WHERE id = 1`)[0].version;
  } catch {
    version = 0;
  }
  if (version < (psqlUpdates.length - 1)) {
    logger.warn(`Migrating PostgreSQL database, which is currently at version ${version}...`);
    try {
      await sql.begin(async (db) => {
        while (version < (psqlUpdates.length - 1)) {
          version++;
          logger.warn(`Running version ${version} update script (${psqlUpdates[version]})...`);
          await db`${psqlUpdates[version]}`;
        }
      });
      const ver = psqlUpdates.length - 1;
      await sql`INSERT INTO settings ${sql({ id: 1, version: ver })} ON CONFLICT (id) DO UPDATE SET version = ${ver}`;
    } catch (e) {
      logger.error(`PostgreSQL migration failed: ${e}`);
      logger.error("Unable to start the bot, quitting now.");
      return 1;
    }
  }
}

export async function getGuild(query) {
  return (await sql`SELECT * FROM guilds WHERE guild_id = ${query}`)[0];
}

export async function setPrefix(prefix, guild) {
  await sql`UPDATE guilds SET prefix = ${prefix} WHERE guild_id = ${guild.id}`;
  prefixCache.set(guild.id, prefix);
}

export async function getTag(guild, tag) {
  const tagResult = await sql`SELECT * FROM tags WHERE guild_id = ${guild} AND name = ${tag}`;
  return tagResult[0] ? { content: tagResult[0].content, author: tagResult[0].author } : undefined;
}

export async function getTags(guild) {
  const tagArray = await sql`SELECT * FROM tags WHERE guild_id = ${guild}`;
  const tags = {};
  for (const tag of tagArray) {
    tags[tag.name] = { content: tag.content, author: tag.author };
  }
  return tags;
}

export async function setTag(name, content, guild) {
  await sql`INSERT INTO tags ${sql({ guild_id: guild.id, name, content: content.content, author: content.author }, "guild_id", "name", "content", "author")}`;
}

export async function editTag(name, content, guild) {
  await sql`UPDATE tags SET content = ${content.content}, author = ${content.author} WHERE guild_id = ${guild.id} AND name = ${name}`;
}

export async function removeTag(name, guild) {
  await sql`DELETE FROM tags WHERE guild_id = ${guild.id} AND name = ${name}`;
}

export async function disableCommand(guild, command) {
  const guildDB = await this.getGuild(guild);
  await sql`UPDATE guilds SET disabled_commands = ${(guildDB.disabled_commands ? [...guildDB.disabled_commands, command] : [command]).filter((v) => !!v)} WHERE guild_id = ${guild}`;
  disabledCmdCache.set(guild, guildDB.disabled_commands ? [...guildDB.disabled_commands, command] : [command].filter((v) => !!v));
}

export async function enableCommand(guild, command) {
  const guildDB = await this.getGuild(guild);
  const newDisabled = guildDB.disabled_commands ? guildDB.disabled_commands.filter(item => item !== command) : [];
  await sql`UPDATE guilds SET disabled_commands = ${newDisabled} WHERE guild_id = ${guild}`;
  disabledCmdCache.set(guild, newDisabled);
}

export async function disableChannel(channel) {
  const guildDB = await this.getGuild(channel.guildID);
  await sql`UPDATE guilds SET disabled_commands = ${[...guildDB.disabled, channel.id]} WHERE guild_id = ${channel.guildID}`;
  disabledCache.set(channel.guildID, [...guildDB.disabled, channel.id]);
}

export async function enableChannel(channel) {
  const guildDB = await this.getGuild(channel.guildID);
  const newDisabled = guildDB.disabled.filter(item => item !== channel.id);
  await sql`UPDATE guilds SET disabled_commands = ${newDisabled} WHERE guild_id = ${channel.guildID}`;
  disabledCache.set(channel.guildID, newDisabled);
}

export async function getCounts() {
  const counts = await sql`SELECT * FROM counts`;
  const countObject = {};
  for (const { command, count } of counts) {
    countObject[command] = count;
  }
  return countObject;
}

export async function addCount(command) {
  await sql`INSERT INTO counts ${sql({ command, count: 1 }, "command", "count")} ON CONFLICT (command) DO UPDATE SET count = counts.count + 1 WHERE counts.command = ${command}`;
}

export async function addGuild(guild) {
  const query = await this.getGuild(guild);
  if (query) return query;
  try {
    await sql`INSERT INTO guilds ${sql({ guild_id: guild.id, prefix: process.env.PREFIX, disabled: [], disabled_commands: [] })}`;
  } catch (e) {
    logger.error(`Failed to register guild ${guild.id}: ${e}`);
  }
  return await this.getGuild(guild.id);
}

export async function fixGuild(guild) {
  const guildDB = await sql`SELECT exists(SELECT 1 FROM guilds WHERE guild_id = ${guild})`;
  if (!guildDB[0].exists) {
    logger.log(`Registering guild database entry for guild ${guild}...`);
    return await this.addGuild(guild);
  }
}

export async function stop() {
  await sql.end();
}