/* This Source Code Form is subject to the terms of the Mozilla Public
 * License, v. 2.0. If a copy of the MPL was not distributed with this
 * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

import stylelint from "stylelint";
import {
  namespace,
  createTokenNamesArray,
  createAllowList,
  getLocalCustomProperties,
  getColorProperties,
  isValidValue,
} from "../helpers.mjs";

const {
  utils: { report, ruleMessages, validateOptions },
} = stylelint;

// Name our rule, set the error message, and link to meta
const ruleName = namespace("use-background-color-tokens");

const messages = ruleMessages(ruleName, {
  rejected: value => `${value} should use a background-color design token.`,
});

const meta = {
  url: "https://firefox-source-docs.mozilla.org/code-quality/lint/linters/stylelint-plugin-mozilla/rules/use-background-color-tokens.html",
  fixable: false,
};

// Gather an array of the ready css `['var(--token-name)']`
const INCLUDE_CATEGORIES = ["background-color"];

const tokenCSS = createTokenNamesArray(INCLUDE_CATEGORIES);

// Allowed border-color values in CSS
const ALLOW_LIST = createAllowList([
  "transparent",
  "currentColor",
  "auto",
  "normal",
  "none",
]);

const CSS_PROPERTIES = ["background", "background-color"];

const ruleFunction = primaryOption => {
  return (root, result) => {
    const validOptions = validateOptions(result, ruleName, {
      actual: primaryOption,
      possible: [true],
    });

    if (!validOptions) {
      return;
    }

    // The first time through gathers our custom properties
    const cssCustomProperties = getLocalCustomProperties(root);

    // And then we validate our properties
    root.walkDecls(declarations => {
      const { prop, value } = declarations;

      // If the property is not in our list to check, skip it
      if (!CSS_PROPERTIES.includes(prop)) {
        return;
      }

      // This rule only cares about colors, so all other shorthand properties are ignored
      const colorProperties = getColorProperties(value);
      const allColorsAreValid = colorProperties.every(property =>
        isValidValue(property, tokenCSS, cssCustomProperties, ALLOW_LIST)
      );

      if (allColorsAreValid) {
        return;
      }

      report({
        message: messages.rejected(declarations.value),
        node: declarations,
        result,
        ruleName,
      });
    });
  };
};

ruleFunction.ruleName = ruleName;
ruleFunction.messages = messages;
ruleFunction.meta = meta;

export default ruleFunction;