R/internal-pheatmap.R

In acidgenomics/AcidPlots: Acid Genomics Plot Functions and Themes

#' Empty pheatmap annotations
#'
#' @note Updated 2019-08-21.
#' @noRd
.emptyPheatmapAnnotations <- list(
    "annotationCol" = NA,
    "annotationColors" = NA
)



#' Generate pheatmap annotation data
#'
## Automatically handle the annotation data and colors.
#'
#' @note Updated 2021-02-26.
#' @noRd
#'
#' @details
#' Factors with a single level are automatically dropped.
#'
#' pheatmap requires `NA` if annotations are empty.
#'
#' Drop any remaining factor columns that contain a single value. Note that
#' we don't want to necessarily use `levels()` in place of `unique()` here,
#' in case we have a situation where we're comparing a value against `NA`.
#' Here this will a level of 1, even though we have 2 unique values. This
#' approach handles NA values better than using `levels()`.
.pheatmapAnnotations <-
    function(object,
             denylist = "sampleName",
             legendColor) {
        assert(
            is(object, "SummarizedExperiment"),
            isCharacter(denylist),
            isHexColorFunction(legendColor, nullOk = TRUE)
        )
        empty <- .emptyPheatmapAnnotations
        data <- colData(object)
        interestingGroups <- interestingGroups(object)
        ok <- hasDims(data) &&
            hasLength(interestingGroups) &&
            !identical(interestingGroups, "sampleName")
        if (!isTRUE(ok)) {
            return(empty)
        }
        assert(
            hasRownames(data),
            isSubset(interestingGroups, colnames(data))
        )
        data <- data[, interestingGroups, drop = FALSE]
        denylist <- unique(c("sampleName", denylist))
        cols <- setdiff(colnames(data), denylist)
        if (!hasLength(cols)) {
            return(empty)
        }
        data <- data[, cols, drop = FALSE]
        keep <- bapply(X = data, FUN = is.factor)
        if (!any(keep)) {
            return(empty)
        }
        data <- data[, keep, drop = FALSE]
        rownames <- rownames(data)
        data <- as.data.frame(lapply(
            X = data,
            FUN = function(x) {
                x <- as.character(x)
                x <- strReplaceNa(x)
                x <- as.factor(x)
                x
            }
        ))
        rownames(data) <- rownames
        hasMultiple <- bapply(
            X = data,
            FUN = function(x) {
                length(unique(x)) > 1L
            }
        )
        if (!hasLength(hasMultiple)) {
            return(empty)
        }
        data <- data[, hasMultiple, drop = FALSE]
        if (is.function(legendColor)) {
            colors <- lapply(
                X = data,
                FUN = function(x) {
                    assert(is.factor(x))
                    levels <- levels(x)
                    colors <- legendColor(length(levels))
                    names(colors) <- levels
                    colors
                }
            )
            names(colors) <- colnames(data)
        } else {
            colors <- NA
        }
        list(
            "annotationCol" = as.data.frame(data),
            "annotationColors" = colors
        )
    }



#' Generate pheatmap arguments
#'
#' @note Updated 2021-09-03.
#' @noRd
#'
#' @details
#' Sanitize formals into snake case and abort on duplicates. Duplicates may
#' arise if user is mixing and matching camel/snake case.
.pheatmapArgs <- function(args) {
    requireNamespaces("pheatmap")
    assert(is.list(args), hasNames(args))
    ## Abort on snake case formatted formal args.
    invalidNames <- grep("[._]", names(args), value = TRUE)
    if (hasLength(invalidNames)) {
        abort(sprintf(
            "Specify arguments in camel case: %s.",
            toInlineString(invalidNames, n = 5L)
        ))
    }
    names(args) <- snakeCase(names(args))
    assert(
        isSubset(
            x = names(args),
            y = formalArgs(pheatmap::pheatmap)
        ),
        hasNoDuplicates(names(args))
    )
    args
}



#' Generate pheatmap color palette
#'
#' @note Updated 2021-02-08.
#' @noRd
#'
#' @details
#' If `color = NULL`, use the pheatmap default palette.
.pheatmapColorPalette <- function(color = NULL, n = 256L) {
    if (is.character(color)) {
        ## Hexadecimal color palette (e.g. RColorBrewer, viridis return).
        assert(allAreHexColors(color))
        color
    } else if (is.function(color)) {
        ## Hexadecimal color function (e.g. viridis functions).
        assert(isHexColorFunction(color))
        color(n = n)
    } else {
        ## pheatmap default palette.
        ## Note that `n` argument won't get evaluated here.
        requireNamespaces("pheatmap")
        eval(formals(pheatmap::pheatmap)[["color"]])
    }
}