const {ApplicationCommandOptionTypes, MessageFlags} =
  require("@projectdysnomia/dysnomia").Constants;
const InteractionCommand = require("../lib/interactionCommand.js");
const {getOption} = require("../lib/interactionDispatcher.js");

const events = require("../lib/events.js");
const {hasFlag} = require("../lib/guildSettings.js");
const REGEX_GITHUB =
  /(?:\s|^)(\|\|\s*)?https?:\/\/(www\.)?github\.com\/[a-z0-9-]+\/[a-z0-9-._]+\/blob\/([a-z0-9-_.?&=#/%]*)(\s*\|\|)?/gi;
const REGEX_GITLAB =
  /(?:\s|^)(\|\|\s*)?https?:\/\/.+?\/[a-z0-9-]+\/[a-z0-9-._]+\/-\/blob\/([a-z0-9-_.?&=#/%]*)(\s*\|\|)?/gi;
const REGEX_GITEA =
  /(?:\s|^)(\|\|\s*)?https?:\/\/.+?\/[a-z0-9-]+\/[a-z0-9-._]+\/src\/(branch|commit)\/([a-z0-9-_.?&=#/%]*)(\s*\|\|)?/gi;
const REGEX_SPOILER = /(?:\s|^)\|\|([\s\S]+?)\|\|/;

function unindent(str) {
  str = str.replace(/\t/g, "    ");
  const minIndent =
    str
      .match(/^ *(?=\S)/gm)
      ?.reduce((prev, curr) => Math.min(prev, curr.length), Infinity) ?? 0;
  if (!minIndent) return str;
  return str.replace(new RegExp(`^ {${minIndent}}`, "gm"), "");
}

const fileTypeAliases = {
  astro: "jsx",
  svelte: "jsx",
  vue: "jsx",
  mdx: "md",
  jsonc: "json",
  json5: "json",
  jsonld: "json",
  "sublime-build": "json",
  "sublime-settings": "json",
  "sublime-menu": "json",
  "sublime-commands": "json",
  "sublime-project": "json",
  "sublime-mousemap": "json",
  "sublime-keymap": "json",
  "sublime-macro": "json",
  "sublime-completions": "json",
  "code-workspace": "json",
  "code-snippets": "json",
};

async function processFile(
  link,
  originalLink,
  spoiler = false,
  linkFile = false
) {
  link = link.replaceAll("||", "").trim();
  const res = await fetch(link);
  if (!res.ok) return "";
  if (!res.headers.get("Content-Type").startsWith("text/plain")) return "";
  const file = await res.text();
  const lines = file.replace(/\r/g, "").split("\n");

  const urlObj = new URL(link);

  let fileName = decodeURIComponent(urlObj.pathname).substring(
    urlObj.pathname.lastIndexOf("/") + 1,
    urlObj.pathname.length
  );
  const fileType =
    fileName.lastIndexOf(".") == -1
      ? ""
      : fileName.substring(fileName.lastIndexOf(".") + 1);

  if (linkFile) {
    fileName = `[${fileName}](<${originalLink}>)`;
  }

  const lineStr = urlObj.hash.match(/#L\d+(-L?\d+)?/)?.[0];
  let startLine, endLine;
  let entireFile = false;

  if (lineStr) {
    const [start, end] = lineStr.match(/\d+/g);
    if (!end) {
      startLine = endLine = start;
    } else {
      startLine = start;
      endLine = end;
    }
  } else {
    entireFile = true;
    startLine = 0;
    endLine = lines.length;
  }

  const whichLines = entireFile
    ? ""
    : startLine == endLine
    ? "Line " + startLine
    : "Lines " + startLine + "-" + endLine;

  if (entireFile) {
    if (fileType == "md") return "";
    if (lines.length > 20) return "";
  }

  let targetLines = (
    entireFile ? lines : lines.slice(startLine - 1, endLine)
  ).join("\n");

  let warning = "";
  if (spoiler && targetLines.includes("||")) {
    targetLines = targetLines.replaceAll("||", "|\u200b|");
    warning = " - :warning: Zero width spaces present";
  }
  if (targetLines.includes("``")) {
    targetLines = targetLines.replaceAll("``", "`\u200b`");
    warning = " - :warning: Zero width spaces present";
  }

  return `**${fileName}:** ${whichLines}${warning}\n${
    spoiler ? "||" : ""
  }\`\`\`${fileTypeAliases[fileType] ?? fileType}\n${unindent(
    targetLines
  )}\n\`\`\`${spoiler ? "||" : ""}`;
}

events.add("messageCreate", "codePreviews", async function (msg) {
  if (msg.author.id == hf.bot.user.id) return;
  if (!msg.guildID) return;
  if (!(await hasFlag(msg.guildID, "codePreviews"))) return;

  const files = [];

  const githubLinks = msg.content.match(REGEX_GITHUB);
  const gitlabLinks = msg.content.match(REGEX_GITLAB);
  const giteaLinks = msg.content.match(REGEX_GITEA);

  if (githubLinks?.length) {
    for (const link of githubLinks) {
      const spoiler = REGEX_SPOILER.test(link);
      files.push(
        await processFile(link.replace("/blob/", "/raw/"), link, spoiler)
      );
    }
  }

  if (gitlabLinks?.length) {
    for (const link of gitlabLinks) {
      const spoiler = REGEX_SPOILER.test(link);
      files.push(
        await processFile(link.replace("/blob/", "/raw/"), link, spoiler)
      );
    }
  }

  if (giteaLinks?.length) {
    for (const link of giteaLinks) {
      const spoiler = REGEX_SPOILER.test(link);
      files.push(
        await processFile(link.replace("/src/", "/raw/"), link, spoiler)
      );
    }
  }

  let out = "";
  const allFiles = files.join("\n").trim();
  if (allFiles !== "" && allFiles.length <= 2000) {
    await msg.edit({flags: MessageFlags.SUPPRESS_EMBEDS}).catch(() => {});
  }
  for (let i = 0; i < files.length; i++) {
    const file = files[i];
    if (file === "") continue;

    if (out.length + file.length > 2000) {
      await msg.channel.createMessage({
        content: out,
        allowedMentions: {
          repliedUser: false,
        },
        messageReference: {
          messageID: msg.id,
        },
      });

      out = file;
    } else {
      out += "\n" + file;
      out = out.trim();
    }

    if (i == files.length - 1 && out.length <= 2000) {
      await msg.channel.createMessage({
        content: out,
        allowedMentions: {
          repliedUser: false,
        },
        messageReference: {
          messageID: msg.id,
        },
      });
    }
  }
});

const codepreviewsCommand = new InteractionCommand("codepreview");
codepreviewsCommand.helpText =
  "Post snippets of codes from files on GitHub, Gitlab and Gitea instances.";
codepreviewsCommand.options.url = {
  name: "url",
  type: ApplicationCommandOptionTypes.STRING,
  description: "URL to attempt to parse",
  required: true,
  default: "",
};
codepreviewsCommand.options.spoiler = {
  name: "spoiler",
  type: ApplicationCommandOptionTypes.BOOLEAN,
  description: "Send spoilered",
  required: false,
  default: false,
};
codepreviewsCommand.callback = async function (interaction) {
  const url = getOption(interaction, codepreviewsCommand, "url");
  const spoiler = getOption(interaction, codepreviewsCommand, "spoiler");

  const githubOrGitlab = url.match(REGEX_GITHUB) ?? url.match(REGEX_GITLAB);
  const gitea = url.match(REGEX_GITEA);

  let out = "";
  if (githubOrGitlab) {
    out = await processFile(url.replace("/blob/", "/raw/"), url, spoiler, true);
  } else if (gitea) {
    out = await processFile(url.replace("/src/", "/raw/"), url, spoiler, true);
  } else {
    return {
      content: "Provided link did not match any services.",
      flags: MessageFlags.EPHEMERAL,
    };
  }

  if (out == "") {
    return {
      content:
        "No content was returned. Provided file is either too long, a markdown file, or not plaintext.",
      flags: MessageFlags.EPHEMERAL,
    };
  }

  if (out.length > 2000) {
    return {
      content: "Provided file is too long.",
      flags: MessageFlags.EPHEMERAL,
    };
  }

  return out;
};
hf.registerCommand(codepreviewsCommand);