// -----------------------------------------
// GRID 
//   Based on ZURB's Foundation 4
// -----------------------------------------

$row-max-width   : 1140px !default;
$total-columns   : 12 !default;
$column-gutter   : 20px !default;

// Calculate percentages for grid
@function gridCalc($colNumber, $totalColumns) {
  @return percentage($colNumber / $totalColumns);
}

// ---------------------------------
// GRID ROW
//   Create container for the grid
// ---------------------------------
@mixin grid-row(
  $nest      : false,
  $collapse  : false,
  $width     : $row-max-width,
  $gutter    : $column-gutter,
  $for-base  : false ) {

  @if $for-base {
    margin: 0 auto;
    width: 100%;
    max-width: $width + $gutter;
    
    @if not $responsive {
      min-width: $width + $gutter;
    }
    @include clearfix;
  }

  $gutter: em($gutter);
  
  @if $nest and $collapse {
    width: auto;
    max-width: none;
    margin: 0;
    padding-right: 0;
    padding-left: 0;
  }

  @else if $nest {
    width: auto;
    max-width: none;
    margin-right: -($gutter / 2);
    margin-left: -($gutter / 2);
  }

  @else if $collapse {
    width: 100%;
    max-width: $width;
    margin: 0 auto;
    padding-right: $gutter / 2;
    padding-left: $gutter / 2;
  }
}

@mixin external-call-column(
  $column : 0,
  $total  : 0,
  $offset : 0,
  $parent-offset : 0) {
  
  @if $column > 0 {
    width: gridCalc($column, $total);
  } @else {
    width: 100%;
  }

  // Offset is only allowed if the column is specified
  @if $column > 0 and $offset > 0 {
    margin-#{$default-float}: gridCalc($offset, $total);
  }
  // If parent (larger) column has offset, remove it
  @else if $parent-offset > 0 {
    margin-#{$default-float}: 0;
  }
}

// ------------------------
// GRID COLUMN
//   Create the grid
// ------------------------
@mixin grid-column(
  $large  : 0,
  $small  : 0, // For external call only, small size screen
  $mini   : 0, // For external call only, mini size screen
  $large-offset : 0,
  $small-offset : 0, // For external call only
  $mini-offset  : 0, // For external call only
  $push  : 0,
  $pull  : 0,
  $collapse  : false,
  $center    : false,
  $gutter    : $column-gutter,
  $total     : $total-columns,
  $for-base  : false ) {

  @if $for-base {
    position: relative;
    float: $default-float;
    padding-right: em($gutter) / 2;
    padding-left: em($gutter) / 2;
  }

  // If gutter's value is different from default, it means it is passed as param
  @if not $gutter == $column-gutter {
    padding-right: em($gutter) / 2;
    padding-left: em($gutter) / 2;
  }

  // If collapsed, get rid of distance padding
  @if $collapse {
    padding-right: 0;
    padding-left: 0;
  }

  // If offset, calculate appropriate margins
  @if $large-offset > 0 { 
    margin-#{$default-float}: gridCalc($large-offset, $total);
  }

  // If a column number is given, calculate width
  @if $large > 0 {
    width: gridCalc($large, $total);
  }

  // Source Ordering, adds left/right depending on which you use.
  @if $push > 0 {
    #{$default-float}: gridCalc($push, $total);
    #{$default-opposite}: auto;
  }
  @if $pull > 0 {
    #{$default-opposite}: gridCalc($pull, $total);
    #{$default-float}: auto;
  }

  // If centered, get rid of float and add auto margin
  @if $center {
    display: block;
    float: none;
    margin-right: auto !important;
    margin-left: auto !important;
  }
  
  // If external call and responsive is true
  @if $external-call and $responsive {
    // If small column is specified
    @if $small > 0 {
      @include below(small) {
        @include external-call-column($column:$small, $total:$total, $offset:$small-offset, $parent-offset:$large-offset);
      }
      
      // Mini column is allowed only if Small column is specified
      @if $mini > 0 {
        @include below(mini) {
          @include external-call-column($column:$mini, $total:$total, $offset:$mini-offset, $parent-offset:$small-offset);
        }
      }
      // If mini is not passed, stack the column
      @else {
        @include below(mini) {
          @include external-call-column($column:$mini, $total:$total, $offset:$mini-offset, $parent-offset:$small-offset);
        }
      }
    }
    // If small is not passed, stack the column
    @else {
      @include below(small) {
        @include external-call-column($column:$small, $total:$total, $offset:$small-offset, $parent-offset:$large-offset);
      }
    }
  }
}

@if $include-grid {

/* ---------------
EDGE Grid
--------------- */

// Normal row
.row {
  @include grid-row($for-base:true);
  
  // Collapsed row
  &.collapse {
    @include grid-row($collapse:true);
    .column,
    .columns {
      @include grid-column($collapse:true);
    }
  }
  
  // Nested-collapsed row
  .row {
    @include grid-row($nest:true);
    &.collapse {
      @include grid-row($nest:true, $collapse:true);
    }
  }
}

// Normal column
.column,
.columns {
  @include grid-column($large:$total-columns, $for-base:true);
}

@for $i from 1 through $total-columns {
  .large#{-$i} { @include grid-column($large:$i); }
}

// Centered column
.column.large-centered,
.columns.large-centered {
  @include grid-column($center:true);
}

// Source Ordering
@include above(small) {
  @for $i from 1 through $total-columns - 1 {
    .large-offset-#{$i} {
      @include grid-column($large-offset:$i);
    }
    .push#{-$i} {
      @include grid-column($push:$i);
    }
    .pull#{-$i} {
      @include grid-column($pull:$i);
    }
  }
}

@if $responsive {
  // Small screen and below
  @include below(small) {
    .column,
    .columns {
      @include grid-column($large:$total-columns);
    }
    @for $i from 1 through $total-columns {
      .small#{-$i} {
        @include grid-column($large:$i);
      }
    }

    @for $i from 0 through $total-columns - 2 {
      .small-offset-#{$i} {
        @include grid-column($large-offset:$i);
      }
    }

    .column.small-centered,
    .columns.small-centered {
      @include grid-column($center:true);
    }
  }

} // responsive

} // $include-grid