'use strict';

const plugin = (options = {}) => (tree) => {
  options.tag = options.tag || "outlook";
  const attributes = ["only", "not", "lt", "lte", "gt", "gte"];
  const versions = {
    2e3: 9,
    2002: 10,
    2003: 11,
    2007: 12,
    2010: 14,
    2013: 15,
    2016: 16,
    2019: 16
  };
  const process = (node) => {
    if (node.tag === `not-${options.tag}`) {
      node.tag = false;
      node.content = `<!--[if !mso]><!-->${tree.render(node.content)}<!--<![endif]-->`;
      return node;
    }
    if (node.tag !== options.tag) {
      return node;
    }
    node.tag = false;
    if (Array.isArray(node.content)) {
      for (const line of node.content) {
        if (line.tag && [options.tag, `not-${options.tag}`].includes(line.tag)) {
          line.tag = false;
        }
      }
    }
    if (!hasAttributes(node.attrs, attributes)) {
      node.content = `<!--[if mso]>${tree.render(node.content)}<![endif]-->`;
      return node;
    }
    const foundAttrs = intersectAttributes(node.attrs, attributes);
    const firstAttr = foundAttrs[0];
    const secondAttr = foundAttrs[1] || false;
    if (["only", "not"].includes(firstAttr)) {
      const items = node.attrs[firstAttr].split(",");
      const negation = firstAttr === "not" ? "!" : "";
      if (items.length > 1) {
        let conditions = [];
        for (const item of items) {
          if (versions[item]) {
            conditions.push(`(mso ${versions[item]})`);
          }
        }
        conditions = [...new Set(conditions)];
        conditions = conditions.length > 1 ? conditions.join("|") : conditions[0].replace(/[()]/g, "");
        if (firstAttr === "not") {
          node.content = `<!--[if ${negation}(${conditions})]>${tree.render(node.content)}<![endif]-->`;
        } else {
          node.content = `<!--[if ${conditions}]>${tree.render(node.content)}<![endif]-->`;
        }
      } else if (items.length === 1 && versions[items[0]]) {
        node.content = `<!--[if ${negation}mso ${versions[items[0]]}]>${tree.render(node.content)}<![endif]-->`;
      }
      return node;
    }
    if (arraysMatch(foundAttrs, ["gt", "lt"]) || arraysMatch(foundAttrs, ["gt", "lte"]) || arraysMatch(foundAttrs, ["gte", "lte"]) || arraysMatch(foundAttrs, ["gte", "lt"]) || arraysMatch(foundAttrs, ["lt", "gt"]) || arraysMatch(foundAttrs, ["lt", "gte"]) || arraysMatch(foundAttrs, ["lte", "gte"]) || arraysMatch(foundAttrs, ["lte", "gt"])) {
      if (versions[node.attrs[firstAttr]] && versions[node.attrs[secondAttr]]) {
        node.content = `<!--[if (${firstAttr} mso ${versions[node.attrs[firstAttr]]})&(${secondAttr} mso ${versions[node.attrs[secondAttr]]})]>${tree.render(node.content)}<![endif]-->`;
      }
      return node;
    }
    if (firstAttr === "lt" && versions[node.attrs.lt]) {
      node.content = `<!--[if lt mso ${versions[node.attrs.lt]}]>${tree.render(node.content)}<![endif]-->`;
      return node;
    }
    if (firstAttr === "lte" && versions[node.attrs.lte]) {
      node.content = `<!--[if lte mso ${versions[node.attrs.lte]}]>${tree.render(node.content)}<![endif]-->`;
      return node;
    }
    if (firstAttr === "gt" && versions[node.attrs.gt]) {
      node.content = `<!--[if gt mso ${versions[node.attrs.gt]}]>${tree.render(node.content)}<![endif]-->`;
      return node;
    }
    if (firstAttr === "gte" && versions[node.attrs.gte]) {
      node.content = `<!--[if gte mso ${versions[node.attrs.gte]}]>${tree.render(node.content)}<![endif]-->`;
      return node;
    }
    return node;
  };
  return tree.walk(process);
};
const hasAttributes = (o, a) => o ? Object.keys(o).some((r) => a.includes(r)) : false;
const intersectAttributes = (o, a) => o ? Object.keys(o).filter((r) => a.includes(r)) : false;
const arraysMatch = (first, second) => {
  if (first.length !== second.length) {
    return false;
  }
  for (const [i, element] of first.entries()) {
    if (element !== second[i]) {
      return false;
    }
  }
  return true;
};

module.exports = plugin;