import {
  testElement,
  writingModes,
  testCSSValues,
  testComputedValues,
  makeDeclaration
} from "./test-shared.js";

// Values to use while testing
const testValues = {
  "length": ["1px", "2px", "3px", "4px", "5px"],
  "color": ["rgb(1, 1, 1)", "rgb(2, 2, 2)", "rgb(3, 3, 3)", "rgb(4, 4, 4)", "rgb(5, 5, 5)"],
  "border-style": ["solid", "dashed", "dotted", "double", "groove"],
};

/**
 * Creates a group of physical and logical box properties, such as
 *
 * { physical: {
 *     left: "margin-left", right: "margin-right",
 *     top: "margin-top", bottom: "margin-bottom",
 *   }, logical: {
 *     inlineStart: "margin-inline-start", inlineEnd: "margin-inline-end",
 *     blockStart: "margin-block-start", blockEnd: "margin-block-end",
 *   }, shorthands: {
 *     "margin": ["margin-top", "margin-right", "margin-bottom", "margin-left"],
 *     "margin-inline": ["margin-inline-start", "margin-inline-end"],
 *     "margin-block": ["margin-block-start", "margin-block-end"],
 *   }, type: ["length"], prerequisites: "...", property: "margin-*" }
 *
 * @param {string} property
 *        A string representing the property names, like "margin-*".
 * @param {Object} descriptor
 * @param {string|string[]} descriptor.type
 *        Describes the kind of values accepted by the property, like "length".
 *        Must be a key or a collection of keys from the `testValues` object.
 * @param {Object={}} descriptor.prerequisites
 *        Represents property declarations that are needed by `property` to work.
 *        For example, border-width properties require a border style.
 */
export function createBoxPropertyGroup(property, descriptor) {
  const logical = {};
  const physical = {};
  const shorthands = {};
  for (const axis of ["inline", "block"]) {
    const shorthand = property.replace("*", axis);
    const longhands = [];
    shorthands[shorthand] = longhands;
    for (const side of ["start", "end"]) {
      const logicalSide = axis + "-" + side;
      const camelCase = logicalSide.replace(/-(.)/g, (match, $1) => $1.toUpperCase());
      const longhand = property.replace("*", logicalSide);
      logical[camelCase] = longhand;
      longhands.push(longhand);
    }
  }
  const isInset = property === "inset-*";
  let prerequisites = "";
  for (const physicalSide of ["left", "right", "top", "bottom"]) {
    physical[physicalSide] = isInset ? physicalSide : property.replace("*", physicalSide);
    prerequisites += makeDeclaration(descriptor.prerequisites, physicalSide);
  }
  shorthands[property.replace("-*", "")] =
    ["top", "right", "bottom", "left"].map(physicalSide => physical[physicalSide]);
  const type = [].concat(descriptor.type);
  return {logical, physical, shorthands, type, prerequisites, property};
}

/**
 * Creates a group physical and logical box-corner properties.
 *
 * @param {string} property
 *        A string representing the property names, like "border-*-radius".
 * @param {Object} descriptor
 * @param {string|string[]} descriptor.type
 *        Describes the kind of values accepted by the property, like "length".
 *        Must be a key or a collection of keys from the `testValues` object.
 * @param {Object={}} descriptor.prerequisites
 *        Represents property declarations that are needed by `property` to work.
 *        For example, border-width properties require a border style.
 */
export function createCornerPropertyGroup(property, descriptor) {
  const logical = {};
  const physical = {};
  const shorthands = {};
  for (const logicalCorner of ["start-start", "start-end", "end-start", "end-end"]) {
    const prop = property.replace("*", logicalCorner);
    const [block_side, inline_side] = logicalCorner.split("-");
    const b = "block" + block_side.charAt(0).toUpperCase() + block_side.slice(1);
    const i = "inline" + inline_side.charAt(0).toUpperCase() + inline_side.slice(1);
    const index = b + "-" + i; // e.g. "blockStart-inlineEnd"
    logical[index] = prop;
  }
  let prerequisites = "";
  for (const physicalCorner of ["top-left", "top-right", "bottom-left", "bottom-right"]) {
    const prop = property.replace("*", physicalCorner);
    physical[physicalCorner] = prop;
    prerequisites += makeDeclaration(descriptor.prerequisites, physicalCorner);
  }
  const type = [].concat(descriptor.type);
  return {logical, physical, shorthands, type, prerequisites, property};
}

/**
 * Creates a group of physical and logical sizing properties.
 *
 * @param {string} prefix
 *        One of "", "max-" or "min-".
 */
export function createSizingPropertyGroup(prefix) {
  return {
    logical: {
      inline: `${prefix}inline-size`,
      block: `${prefix}block-size`,
    },
    physical: {
      horizontal: `${prefix}width`,
      vertical: `${prefix}height`,
    },
    type: ["length"],
    prerequisites: makeDeclaration({display: "block"}),
    property: (prefix ? prefix.slice(0, -1) + " " : "") + "sizing",
  };
}

/**
 * Tests a grup of logical and physical properties in different writing modes.
 *
 * @param {Object} group
 *        An object returned by createBoxPropertyGroup or createSizingPropertyGroup.
 */
export function runTests(group) {
  const values = testValues[group.type[0]].map(function(_, i) {
    return group.type.map(type => testValues[type][i]).join(" ");
  });
  const logicals = Object.values(group.logical);
  const physicals = Object.values(group.physical);
  const shorthands = group.shorthands ? Object.entries(group.shorthands) : null;
  const is_corner = group.property == "border-*-radius";

  test(function() {
    const expected = [];
    for (const [i, logicalProp] of logicals.entries()) {
      testElement.style.setProperty(logicalProp, values[i]);
      expected.push([logicalProp, values[i]]);
    }
    testCSSValues("logical properties in inline style", testElement.style, expected);
  }, `Test that logical ${group.property} properties are supported.`);
  testElement.style.cssText = "";

  const shorthandValues = {};
  for (const [shorthand, longhands] of shorthands || []) {
    let valueArray;
    if (group.type.length > 1) {
      valueArray = [values[0]];
    } else {
      valueArray = testValues[group.type].slice(0, longhands.length);
    }
    shorthandValues[shorthand] = valueArray;
    const value = valueArray.join(" ");
    const expected = [[shorthand, value]];
    for (let [i, longhand] of longhands.entries()) {
      expected.push([longhand, valueArray[group.type.length > 1 ? 0 : i]]);
    }
    test(function() {
      testElement.style.setProperty(shorthand, value);
      testCSSValues("shorthand in inline style", testElement.style, expected);
      const stylesheet = `.test { ${group.prerequisites} }`;
      testComputedValues("shorthand in computed style", stylesheet, expected);
    }, `Test that ${shorthand} shorthand sets longhands and serializes correctly.`);
    testElement.style.cssText = "";
  }

  for (const writingMode of writingModes) {
    for (const style of writingMode.styles) {
      const writingModeDecl = makeDeclaration(style);

      const associated = {};
      for (const [logicalSide, logicalProp] of Object.entries(group.logical)) {
        let physicalProp;
        if (is_corner) {
          const [ block_side, inline_side] = logicalSide.split("-");
          const physicalSide1 = writingMode[block_side];
          const physicalSide2 = writingMode[inline_side];
          let physicalCorner;
          // mirror "left-top" to "top-left" etc
          if (["top", "bottom"].includes(physicalSide1)) {
            physicalCorner = physicalSide1 + "-" + physicalSide2;
          } else {
            physicalCorner = physicalSide2 + "-" + physicalSide1;
          }
          physicalProp = group.physical[physicalCorner];
        } else {
          physicalProp = group.physical[writingMode[logicalSide]];
        }
        associated[logicalProp] = physicalProp;
        associated[physicalProp] = logicalProp;
      }

      // Test that logical properties are converted to their physical
      // equivalent correctly when all in the group are present on a single
      // declaration, with no overwriting of previous properties and
      // no physical properties present.  We put the writing mode properties
      // on a separate declaration to test that the computed values of these
      // properties are used, rather than those on the same declaration.
      test(function() {
        let decl = group.prerequisites;
        const expected = [];
        for (const [i, logicalProp] of logicals.entries()) {
          decl += `${logicalProp}: ${values[i]}; `;
          expected.push([logicalProp, values[i]]);
          expected.push([associated[logicalProp], values[i]]);
        }
        testComputedValues("logical properties on one declaration, writing " +
                           `mode properties on another, '${writingModeDecl}'`,
                           `.test { ${writingModeDecl} } .test { ${decl} }`,
                           expected);
      }, `Test that logical ${group.property} properties share computed values `
       + `with their physical associates, with '${writingModeDecl}'.`);

      // Test logical shorthand properties.
      if (shorthands) {
        test(function() {
          for (const [shorthand, longhands] of shorthands) {
            let valueArray = shorthandValues[shorthand];
            const decl = group.prerequisites + `${shorthand}: ${valueArray.join(" ")}; `;
            const expected = [];
            for (let [i, longhand] of longhands.entries()) {
              const longhandValue = valueArray[group.type.length > 1 ? 0 : i];
              expected.push([longhand, longhandValue]);
              expected.push([associated[longhand], longhandValue]);
            }
            testComputedValues("shorthand properties on one declaration, writing " +
                               `mode properties on another, '${writingModeDecl}'`,
                               `.test { ${writingModeDecl} } .test { ${decl} }`,
                               expected);
          }
        }, `Test that ${group.property} shorthands set the computed value of both `
         + `logical and physical longhands, with '${writingModeDecl}'.`);
      }

      // Test that logical and physical properties are cascaded together,
      // honoring their relative order on a single declaration
      // (a) with a single logical property after the physical ones
      // (b) with a single physical property after the logical ones
      test(function() {
        for (const lastIsLogical of [true, false]) {
          const lasts = lastIsLogical ? logicals : physicals;
          const others = lastIsLogical ? physicals : logicals;
          for (const lastProp of lasts) {
            let decl = writingModeDecl + group.prerequisites;
            const expected = [];
            for (const [i, prop] of others.entries()) {
              decl += `${prop}: ${values[i]}; `;
              const valueIdx = associated[prop] === lastProp ? others.length : i;
              expected.push([prop, values[valueIdx]]);
              expected.push([associated[prop], values[valueIdx]]);
            }
            decl += `${lastProp}: ${values[others.length]}; `;
            testComputedValues(`'${lastProp}' last on single declaration, '${writingModeDecl}'`,
                               `.test { ${decl} }`,
                               expected);
          }
        }
      }, `Test that ${group.property} properties honor order of appearance when both `
       + `logical and physical associates are declared, with '${writingModeDecl}'.`);

      // Test that logical and physical properties are cascaded properly when
      // on different declarations
      // (a) with a logical property in the high specificity rule
      // (b) with a physical property in the high specificity rule
      test(function() {
        for (const highIsLogical of [true, false]) {
          let lowDecl = writingModeDecl + group.prerequisites;
          const high = highIsLogical ? logicals : physicals;
          const others = highIsLogical ? physicals : logicals;
          for (const [i, prop] of others.entries()) {
            lowDecl += `${prop}: ${values[i]}; `;
          }
          for (const highProp of high) {
            const highDecl = `${highProp}: ${values[others.length]}; `;
            const expected = [];
            for (const [i, prop] of others.entries()) {
              const valueIdx = associated[prop] === highProp ? others.length : i;
              expected.push([prop, values[valueIdx]]);
              expected.push([associated[prop], values[valueIdx]]);
            }
            testComputedValues(`'${highProp}', two declarations, '${writingModeDecl}'`,
                               `#test { ${highDecl} } .test { ${lowDecl} }`,
                               expected);
          }
        }
      }, `Test that ${group.property} properties honor selector specificty when both `
       + `logical and physical associates are declared, with '${writingModeDecl}'.`);
    }
  }
}