// Contains the interpretation of CSS properties, as used by the property optimizer

var breakUp = require('./break-up');
var canOverride = require('./can-override');
var restore = require('./restore');

var override = require('../../utils/override');

// Properties to process
// Extend this object in order to add support for more properties in the optimizer.
//
// Each key in this object represents a CSS property and should be an object.
// Such an object contains properties that describe how the represented CSS property should be handled.
// Possible options:
//
// * components: array (Only specify for shorthand properties.)
//   Contains the names of the granular properties this shorthand compacts.
//
// * canOverride: function
//   Returns whether two tokens of this property can be merged with each other.
//   This property has no meaning for shorthands.
//
// * defaultValue: string
//   Specifies the default value of the property according to the CSS standard.
//   For shorthand, this is used when every component is set to its default value, therefore it should be the shortest possible default value of all the components.
//
// * shortestValue: string
//   Specifies the shortest possible value the property can possibly have.
//   (Falls back to defaultValue if unspecified.)
//
// * breakUp: function (Only specify for shorthand properties.)
//   Breaks the shorthand up to its components.
//
// * restore: function (Only specify for shorthand properties.)
//   Puts the shorthand together from its components.
//
var compactable = {
  'background': {
    canOverride: canOverride.generic.components([
      canOverride.generic.image,
      canOverride.property.backgroundPosition,
      canOverride.property.backgroundSize,
      canOverride.property.backgroundRepeat,
      canOverride.property.backgroundAttachment,
      canOverride.property.backgroundOrigin,
      canOverride.property.backgroundClip,
      canOverride.generic.color
    ]),
    components: [
      'background-image',
      'background-position',
      'background-size',
      'background-repeat',
      'background-attachment',
      'background-origin',
      'background-clip',
      'background-color'
    ],
    breakUp: breakUp.multiplex(breakUp.background),
    defaultValue: '0 0',
    restore: restore.multiplex(restore.background),
    shortestValue: '0',
    shorthand: true
  },
  'background-attachment': {
    canOverride: canOverride.property.backgroundAttachment,
    componentOf: [
      'background'
    ],
    defaultValue: 'scroll'
  },
  'background-clip': {
    canOverride: canOverride.property.backgroundClip,
    componentOf: [
      'background'
    ],
    defaultValue: 'border-box',
    shortestValue: 'border-box'
  },
  'background-color': {
    canOverride: canOverride.generic.color,
    componentOf: [
      'background'
    ],
    defaultValue: 'transparent',
    multiplexLastOnly: true,
    nonMergeableValue: 'none',
    shortestValue: 'red'
  },
  'background-image': {
    canOverride: canOverride.generic.image,
    componentOf: [
      'background'
    ],
    defaultValue: 'none'
  },
  'background-origin': {
    canOverride: canOverride.property.backgroundOrigin,
    componentOf: [
      'background'
    ],
    defaultValue: 'padding-box',
    shortestValue: 'border-box'
  },
  'background-position': {
    canOverride: canOverride.property.backgroundPosition,
    componentOf: [
      'background'
    ],
    defaultValue: ['0', '0'],
    doubleValues: true,
    shortestValue: '0'
  },
  'background-repeat': {
    canOverride: canOverride.property.backgroundRepeat,
    componentOf: [
      'background'
    ],
    defaultValue: ['repeat'],
    doubleValues: true
  },
  'background-size': {
    canOverride: canOverride.property.backgroundSize,
    componentOf: [
      'background'
    ],
    defaultValue: ['auto'],
    doubleValues: true,
    shortestValue: '0 0'
  },
  'bottom': {
    canOverride: canOverride.property.bottom,
    defaultValue: 'auto'
  },
  'border': {
    breakUp: breakUp.border,
    canOverride: canOverride.generic.components([
      canOverride.generic.unit,
      canOverride.property.borderStyle,
      canOverride.generic.color
    ]),
    components: [
      'border-width',
      'border-style',
      'border-color'
    ],
    defaultValue: 'none',
    overridesShorthands: [
      'border-bottom',
      'border-left',
      'border-right',
      'border-top'
    ],
    restore: restore.withoutDefaults,
    shorthand: true,
    shorthandComponents: true
  },
  'border-bottom': {
    breakUp: breakUp.border,
    canOverride: canOverride.generic.components([
      canOverride.generic.unit,
      canOverride.property.borderStyle,
      canOverride.generic.color
    ]),
    components: [
      'border-bottom-width',
      'border-bottom-style',
      'border-bottom-color'
    ],
    defaultValue: 'none',
    restore: restore.withoutDefaults,
    shorthand: true
  },
  'border-bottom-color': {
    canOverride: canOverride.generic.color,
    componentOf: [
      'border-bottom',
      'border-color'
    ],
    defaultValue: 'none'
  },
  'border-bottom-left-radius': {
    canOverride: canOverride.generic.unit,
    componentOf: [
      'border-radius'
    ],
    defaultValue: '0',
    vendorPrefixes: [
      '-moz-',
      '-o-'
    ]
  },
  'border-bottom-right-radius': {
    canOverride: canOverride.generic.unit,
    componentOf: [
      'border-radius'
    ],
    defaultValue: '0',
    vendorPrefixes: [
      '-moz-',
      '-o-'
    ]
  },
  'border-bottom-style': {
    canOverride: canOverride.property.borderStyle,
    componentOf: [
      'border-bottom',
      'border-style'
    ],
    defaultValue: 'none'
  },
  'border-bottom-width': {
    canOverride: canOverride.generic.unit,
    componentOf: [
      'border-bottom',
      'border-width'
    ],
    defaultValue: 'medium',
    shortestValue: '0'
  },
  'border-collapse': {
    canOverride: canOverride.property.borderCollapse,
    defaultValue: 'separate'
  },
  'border-color': {
    breakUp: breakUp.fourValues,
    canOverride: canOverride.generic.components([
      canOverride.generic.color,
      canOverride.generic.color,
      canOverride.generic.color,
      canOverride.generic.color
    ]),
    componentOf: ['border'],
    components: [
      'border-top-color',
      'border-right-color',
      'border-bottom-color',
      'border-left-color'
    ],
    defaultValue: 'none',
    restore: restore.fourValues,
    shortestValue: 'red',
    shorthand: true
  },
  'border-left': {
    breakUp: breakUp.border,
    canOverride: canOverride.generic.components([
      canOverride.generic.unit,
      canOverride.property.borderStyle,
      canOverride.generic.color
    ]),
    components: [
      'border-left-width',
      'border-left-style',
      'border-left-color'
    ],
    defaultValue: 'none',
    restore: restore.withoutDefaults,
    shorthand: true
  },
  'border-left-color': {
    canOverride: canOverride.generic.color,
    componentOf: [
      'border-color',
      'border-left'
    ],
    defaultValue: 'none'
  },
  'border-left-style': {
    canOverride: canOverride.property.borderStyle,
    componentOf: [
      'border-left',
      'border-style'
    ],
    defaultValue: 'none'
  },
  'border-left-width': {
    canOverride: canOverride.generic.unit,
    componentOf: [
      'border-left',
      'border-width'
    ],
    defaultValue: 'medium',
    shortestValue: '0'
  },
  'border-radius': {
    breakUp: breakUp.borderRadius,
    canOverride: canOverride.generic.components([
      canOverride.generic.unit,
      canOverride.generic.unit,
      canOverride.generic.unit,
      canOverride.generic.unit
    ]),
    components: [
      'border-top-left-radius',
      'border-top-right-radius',
      'border-bottom-right-radius',
      'border-bottom-left-radius'
    ],
    defaultValue: '0',
    restore: restore.borderRadius,
    shorthand: true,
    vendorPrefixes: [
      '-moz-',
      '-o-'
    ]
  },
  'border-right': {
    breakUp: breakUp.border,
    canOverride: canOverride.generic.components([
      canOverride.generic.unit,
      canOverride.property.borderStyle,
      canOverride.generic.color
    ]),
    components: [
      'border-right-width',
      'border-right-style',
      'border-right-color'
    ],
    defaultValue: 'none',
    restore: restore.withoutDefaults,
    shorthand: true
  },
  'border-right-color': {
    canOverride: canOverride.generic.color,
    componentOf: [
      'border-color',
      'border-right'
    ],
    defaultValue: 'none'
  },
  'border-right-style': {
    canOverride: canOverride.property.borderStyle,
    componentOf: [
      'border-right',
      'border-style'
    ],
    defaultValue: 'none'
  },
  'border-right-width': {
    canOverride: canOverride.generic.unit,
    componentOf: [
      'border-right',
      'border-width'
    ],
    defaultValue: 'medium',
    shortestValue: '0'
  },
  'border-style': {
    breakUp: breakUp.fourValues,
    canOverride: canOverride.generic.components([
      canOverride.property.borderStyle,
      canOverride.property.borderStyle,
      canOverride.property.borderStyle,
      canOverride.property.borderStyle
    ]),
    componentOf: [
      'border'
    ],
    components: [
      'border-top-style',
      'border-right-style',
      'border-bottom-style',
      'border-left-style'
    ],
    defaultValue: 'none',
    restore: restore.fourValues,
    shorthand: true
  },
  'border-top': {
    breakUp: breakUp.border,
    canOverride: canOverride.generic.components([
      canOverride.generic.unit,
      canOverride.property.borderStyle,
      canOverride.generic.color
    ]),
    components: [
      'border-top-width',
      'border-top-style',
      'border-top-color'
    ],
    defaultValue: 'none',
    restore: restore.withoutDefaults,
    shorthand: true
  },
  'border-top-color': {
    canOverride: canOverride.generic.color,
    componentOf: [
      'border-color',
      'border-top'
    ],
    defaultValue: 'none'
  },
  'border-top-left-radius': {
    canOverride: canOverride.generic.unit,
    componentOf: [
      'border-radius'
    ],
    defaultValue: '0',
    vendorPrefixes: [
      '-moz-',
      '-o-'
    ]
  },
  'border-top-right-radius': {
    canOverride: canOverride.generic.unit,
    componentOf: [
      'border-radius'
    ],
    defaultValue: '0',
    vendorPrefixes: [
      '-moz-',
      '-o-'
    ]
  },
  'border-top-style': {
    canOverride: canOverride.property.borderStyle,
    componentOf: [
      'border-style',
      'border-top'
    ],
    defaultValue: 'none'
  },
  'border-top-width': {
    canOverride: canOverride.generic.unit,
    componentOf: [
      'border-top',
      'border-width'
    ],
    defaultValue: 'medium',
    shortestValue: '0'
  },
  'border-width': {
    breakUp: breakUp.fourValues,
    canOverride: canOverride.generic.components([
      canOverride.generic.unit,
      canOverride.generic.unit,
      canOverride.generic.unit,
      canOverride.generic.unit
    ]),
    components: [
      'border-top-width',
      'border-right-width',
      'border-bottom-width',
      'border-left-width'
    ],
    defaultValue: 'medium',
    restore: restore.fourValues,
    shortestValue: '0',
    shorthand: true
  },
  'clear': {
    canOverride: canOverride.property.clear,
    defaultValue: 'none'
  },
  'color': {
    canOverride: canOverride.generic.color,
    defaultValue: 'transparent',
    shortestValue: 'red'
  },
  'cursor': {
    canOverride: canOverride.property.cursor,
    defaultValue: 'auto'
  },
  'display': {
    canOverride: canOverride.property.display,
  },
  'float': {
    canOverride: canOverride.property.float,
    defaultValue: 'none'
  },
  'font-size': {
    canOverride: canOverride.generic.unit,
    defaultValue: 'medium',
    shortestValue: '0'
  },
  'font-style': {
    canOverride: canOverride.property.fontStyle,
    defaultValue: 'normal'
  },
  'font-weight': {
    canOverride: canOverride.property.fontWeight,
    defaultValue: '400',
    shortestValue: '400'
  },
  'height': {
    canOverride: canOverride.generic.unit,
    defaultValue: 'auto',
    shortestValue: '0'
  },
  'left': {
    canOverride: canOverride.property.left,
    defaultValue: 'auto'
  },
  'line-height': {
    canOverride: canOverride.generic.unit,
    defaultValue: 'normal',
    shortestValue: '0'
  },
  'list-style': {
    canOverride: canOverride.generic.components([
      canOverride.property.listStyleType,
      canOverride.property.listStylePosition,
      canOverride.property.listStyleImage
    ]),
    components: [
      'list-style-type',
      'list-style-position',
      'list-style-image'
    ],
    breakUp: breakUp.listStyle,
    restore: restore.withoutDefaults,
    defaultValue: 'outside', // can't use 'disc' because that'd override default 'decimal' for <ol>
    shortestValue: 'none',
    shorthand: true
  },
  'list-style-image' : {
    canOverride: canOverride.generic.image,
    componentOf: [
      'list-style'
    ],
    defaultValue: 'none'
  },
  'list-style-position' : {
    canOverride: canOverride.property.listStylePosition,
    componentOf: [
      'list-style'
    ],
    defaultValue: 'outside',
    shortestValue: 'inside'
  },
  'list-style-type' : {
    canOverride: canOverride.property.listStyleType,
    componentOf: [
      'list-style'
    ],
    // NOTE: we can't tell the real default value here, it's 'disc' for <ul> and 'decimal' for <ol>
    // this is a hack, but it doesn't matter because this value will be either overridden or
    // it will disappear at the final step anyway
    defaultValue: 'decimal|disc',
    shortestValue: 'none'
  },
  'margin': {
    breakUp: breakUp.fourValues,
    canOverride: canOverride.generic.components([
      canOverride.generic.unit,
      canOverride.generic.unit,
      canOverride.generic.unit,
      canOverride.generic.unit
    ]),
    components: [
      'margin-top',
      'margin-right',
      'margin-bottom',
      'margin-left'
    ],
    defaultValue: '0',
    restore: restore.fourValues,
    shorthand: true
  },
  'margin-bottom': {
    canOverride: canOverride.generic.unit,
    componentOf: [
      'margin'
    ],
    defaultValue: '0'
  },
  'margin-left': {
    canOverride: canOverride.generic.unit,
    componentOf: [
      'margin'
    ],
    defaultValue: '0'
  },
  'margin-right': {
    canOverride: canOverride.generic.unit,
    componentOf: [
      'margin'
    ],
    defaultValue: '0'
  },
  'margin-top': {
    canOverride: canOverride.generic.unit,
    componentOf: [
      'margin'
    ],
    defaultValue: '0'
  },
  'outline': {
    canOverride: canOverride.generic.components([
      canOverride.generic.color,
      canOverride.property.outlineStyle,
      canOverride.generic.unit
    ]),
    components: [
      'outline-color',
      'outline-style',
      'outline-width'
    ],
    breakUp: breakUp.outline,
    restore: restore.withoutDefaults,
    defaultValue: '0',
    shorthand: true
  },
  'outline-color': {
    canOverride: canOverride.generic.color,
    componentOf: [
      'outline'
    ],
    defaultValue: 'invert',
    shortestValue: 'red'
  },
  'outline-style': {
    canOverride: canOverride.property.outlineStyle,
    componentOf: [
      'outline'
    ],
    defaultValue: 'none'
  },
  'outline-width': {
    canOverride: canOverride.generic.unit,
    componentOf: [
      'outline'
    ],
    defaultValue: 'medium',
    shortestValue: '0'
  },
  'overflow': {
    canOverride: canOverride.property.overflow,
    defaultValue: 'visible'
  },
  'overflow-x': {
    canOverride: canOverride.property.overflow,
    defaultValue: 'visible'
  },
  'overflow-y': {
    canOverride: canOverride.property.overflow,
    defaultValue: 'visible'
  },
  'padding': {
    breakUp: breakUp.fourValues,
    canOverride: canOverride.generic.components([
      canOverride.generic.unit,
      canOverride.generic.unit,
      canOverride.generic.unit,
      canOverride.generic.unit
    ]),
    components: [
      'padding-top',
      'padding-right',
      'padding-bottom',
      'padding-left'
    ],
    defaultValue: '0',
    restore: restore.fourValues,
    shorthand: true
  },
  'padding-bottom': {
    canOverride: canOverride.generic.unit,
    componentOf: [
      'padding'
    ],
    defaultValue: '0'
  },
  'padding-left': {
    canOverride: canOverride.generic.unit,
    componentOf: [
      'padding'
    ],
    defaultValue: '0'
  },
  'padding-right': {
    canOverride: canOverride.generic.unit,
    componentOf: [
      'padding'
    ],
    defaultValue: '0'
  },
  'padding-top': {
    canOverride: canOverride.generic.unit,
    componentOf: [
      'padding'
    ],
    defaultValue: '0'
  },
  'position': {
    canOverride: canOverride.property.position,
    defaultValue: 'static'
  },
  'right': {
    canOverride: canOverride.property.right,
    defaultValue: 'auto'
  },
  'text-align': {
    canOverride: canOverride.property.textAlign,
    // NOTE: we can't tell the real default value here, as it depends on default text direction
    // this is a hack, but it doesn't matter because this value will be either overridden or
    // it will disappear anyway
    defaultValue: 'left|right'
  },
  'text-decoration': {
    canOverride: canOverride.property.textDecoration,
    defaultValue: 'none'
  },
  'text-overflow': {
    canOverride: canOverride.property.textOverflow,
    defaultValue: 'none'
  },
  'text-shadow': {
    canOverride: canOverride.property.textShadow,
    defaultValue: 'none'
  },
  'top': {
    canOverride: canOverride.property.top,
    defaultValue: 'auto'
  },
  'transform': {
    canOverride: canOverride.property.transform,
    vendorPrefixes: [
      '-moz-',
      '-ms-',
      '-webkit-'
    ]
  },
  'vertical-align': {
    canOverride: canOverride.property.verticalAlign,
    defaultValue: 'baseline'
  },
  'visibility': {
    canOverride: canOverride.property.visibility,
    defaultValue: 'visible'
  },
  'white-space': {
    canOverride: canOverride.property.whiteSpace,
    defaultValue: 'normal'
  },
  'width': {
    canOverride: canOverride.generic.unit,
    defaultValue: 'auto',
    shortestValue: '0'
  },
  'z-index': {
    canOverride: canOverride.property.zIndex,
    defaultValue: 'auto'
  }
};

function cloneDescriptor(propertyName, prefix) {
  var clonedDescriptor = override(compactable[propertyName], {});

  if ('componentOf' in clonedDescriptor) {
    clonedDescriptor.componentOf = clonedDescriptor.componentOf.map(function (shorthandName) {
      return prefix + shorthandName;
    });
  }

  if ('components' in clonedDescriptor) {
    clonedDescriptor.components = clonedDescriptor.components.map(function (longhandName) {
      return prefix + longhandName;
    });
  }

  return clonedDescriptor;
}

// generate vendor-prefixed properties
var vendorPrefixedCompactable = {};

for (var propertyName in compactable) {
  var descriptor = compactable[propertyName];

  if (!('vendorPrefixes' in descriptor)) {
    continue;
  }

  for (var i = 0; i < descriptor.vendorPrefixes.length; i++) {
    var prefix = descriptor.vendorPrefixes[i];
    var clonedDescriptor = cloneDescriptor(propertyName, prefix);
    delete clonedDescriptor.vendorPrefixes;

    vendorPrefixedCompactable[prefix + propertyName] = clonedDescriptor;
  }

  delete descriptor.vendorPrefixes;
}

module.exports = override(compactable, vendorPrefixedCompactable);
