// Framework grid generation
//
// Used only by Bootstrap to generate the correct number of grid classes given
// any value of `@grid-columns`.

.make-grid-columns() {
    // Common styles for all sizes of grid columns, widths 1-12
    .rp(@index) { // initial
	@item: ~".rp-xs-@{index}, .rp-sm-@{index}, .rp-md-@{index}, .rp-lg-@{index}";
	.rp((@index + 1), @item);
    }
    .rp(@index, @list) when (@index =< @grid-columns) { // general; "=<" isn't a typo
	@item: ~".rp-xs-@{index}, .rp-sm-@{index}, .rp-md-@{index}, .rp-lg-@{index}";
	.rp((@index + 1), ~"@{list}, @{item}");
    }
    .rp(@index, @list) when (@index > @grid-columns) { // terminal
	@{list} {
	    position: relative;
	    // Prevent columns from collapsing when empty
	    min-height: 1px;
	    // Inner gutter via padding
	    padding-left: ceil((@grid-gutter-width / 2));
	    padding-right: floor((@grid-gutter-width / 2));
	}
    }
    .rp(1); // kickstart it
}

.float-grid-columns(@class) {
    .rp(@index) { // initial
	@item: ~".rp-@{class}-@{index}";
	.rp((@index + 1), @item);
    }
    .rp(@index, @list) when (@index =< @grid-columns) { // general
	@item: ~".rp-@{class}-@{index}";
	.rp((@index + 1), ~"@{list}, @{item}");
    }
    .rp(@index, @list) when (@index > @grid-columns) { // terminal
	@{list} {
	    float: left;
	}
    }
    .rp(1); // kickstart it
}

.calc-grid-column(@index, @class, @type) when (@type = width) and (@index > 0) {
    .rp-@{class}-@{index} {
	width: percentage((@index / @grid-columns));
    }
}

.calc-grid-column(@index, @class, @type) when (@type = push) and (@index > 0) {
    .rp-@{class}-push-@{index} {
	left: percentage((@index / @grid-columns));
    }
}

.calc-grid-column(@index, @class, @type) when (@type = push) and (@index = 0) {
    .rp-@{class}-push-0 {
	left: auto;
    }
}

.calc-grid-column(@index, @class, @type) when (@type = pull) and (@index > 0) {
    .rp-@{class}-pull-@{index} {
	right: percentage((@index / @grid-columns));
    }
}

.calc-grid-column(@index, @class, @type) when (@type = pull) and (@index = 0) {
    .rp-@{class}-pull-0 {
	right: auto;
    }
}

.calc-grid-column(@index, @class, @type) when (@type = offset) {
    .rp-@{class}-offset-@{index} {
	margin-left: percentage((@index / @grid-columns));
    }
}

// Basic looping in LESS
.loop-grid-columns(@index, @class, @type) when (@index >= 0) {
    .calc-grid-column(@index, @class, @type);
    // next iteration
    .loop-grid-columns((@index - 1), @class, @type);
}

// Create grid for specific class
.make-grid(@class) {
    .float-grid-columns(@class);
    .loop-grid-columns(@grid-columns, @class, width);
    .loop-grid-columns(@grid-columns, @class, pull);
    .loop-grid-columns(@grid-columns, @class, push);
    .loop-grid-columns(@grid-columns, @class, offset);
}