From 27a3ec6cad52bc3f4756f5308a37215e72bb4b4e Mon Sep 17 00:00:00 2001
From: Mark Keller <7525285+keller-mark@users.noreply.github.com>
Date: Mon, 14 Aug 2023 17:34:33 -0400
Subject: [PATCH] Refactor dtypes functions

---
 R/array-nested.R | 138 +--------------------------------------------
 R/dtypes.R       | 144 +++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 147 insertions(+), 135 deletions(-)
 create mode 100644 R/dtypes.R

diff --git a/R/array-nested.R b/R/array-nested.R
index e5755fb..7e95635 100644
--- a/R/array-nested.R
+++ b/R/array-nested.R
@@ -1,145 +1,13 @@
-get_dtype_rtype <- function(dtype) {
-    # Reference: https://github.com/gzuidhof/zarr.js/blob/292804/src/nestedArray/types.ts#L32
-  DTYPE_RTYPE_MAPPING <- list(
-    "|b" = logical(),
-    "|u1" = integer(),
-    "|i1" = integer(),
-    "<b" = logical(),
-    "<u1" = integer(),
-    "<i1" = integer(),
-    "<u2" = integer(),
-    "<i2" = integer(),
-    "<u4" = integer(),
-    "<i4" = integer(),
-    "<f4" = double(),
-    "<f8" = double(),
-    ">b" = logical(),
-    ">u1" = integer(),
-    ">i1" = integer(),
-    ">u2" = integer(),
-    ">i2" = integer(),
-    ">u4" = integer(),
-    ">i4" = integer(),
-    ">f4" = double(),
-    ">f8" = double()
-  )
-  return(DTYPE_RTYPE_MAPPING[[dtype]])
-  # TODO: handle errors
-  #stop('Dtype not recognized or not supported in pizzarr')
-}
-
-
-get_dtype_endianness <- function(dtype) {
-  # TODO: use regexes to figure this stuff out
-  DTYPE_ENDIANNESS_MAPPING <- list(
-    "|b" = "nr",
-    "|u1" = "nr",
-    "|i1" = "nr",
-    "<b" = "little",
-    "<u1" = "little",
-    "<i1" = "little",
-    "<u2" = "little",
-    "<i2" = "little",
-    "<u4" = "little",
-    "<i4" = "little",
-    "<f4" = "little",
-    "<f8" = "little",
-    ">b" = "big",
-    ">u1" = "big",
-    ">i1" = "big",
-    ">u2" = "big",
-    ">i2" = "big",
-    ">u4" = "big",
-    ">i4" = "big",
-    ">f4" = "big",
-    ">f8" = "big"
-  )
-  return(DTYPE_ENDIANNESS_MAPPING[[dtype]])
-}
-
-get_dtype_numbytes <- function(dtype) {
-  # TODO: use regexes to figure this stuff out
-  DTYPE_NUMBYTES_MAPPING <- list(
-    "|b" = 1,
-    "|u1" = 1,
-    "|i1" = 1,
-    "<b" = 1,
-    "<u1" = 1,
-    "<i1" = 1,
-    "<u2" = 2,
-    "<i2" = 2,
-    "<u4" = 4,
-    "<i4" = 4,
-    "<f4" = 4,
-    "<f8" = 8,
-    ">b" = 1,
-    ">u1" = 1,
-    ">i1" = 1,
-    ">u2" = 2,
-    ">i2" = 2,
-    ">u4" = 4,
-    ">i4" = 4,
-    ">f4" = 4,
-    ">f8" = 8
-  )
-  return(DTYPE_NUMBYTES_MAPPING[[dtype]])
-}
 
-get_typed_array_ctr <- function(dtype) {
-  rtype <- get_dtype_rtype(dtype)
-  return(function(dim) array(data = rtype, dim = dim))
-}
 
-# Reference: https://github.com/gzuidhof/zarr.js/blob/292804/src/nestedArray/index.ts#L134
+#' @keywords internal
 create_array_from_raw <- function(buf, dtype, shape, offset = 0) {
   # TODO
-}
-
-get_dtype_from_array <- function(a) {
-  TYPEOF_RTYPE_MAPPING <- list(
-    "logical" = logical(),
-    "integer" = integer(),
-    "double" = double()
-  )
-  RTYPE_DTYPE_MAPPING <- list(
-    "logical" = "|b",
-    "integer" = "<i4",
-    "double" = "<f8"
-  )
-  rtype_str <- typeof(a)
-  return(RTYPE_DTYPE_MAPPING[[rtype_str]])
-}
+  # Reference: https://github.com/gzuidhof/zarr.js/blob/292804/src/nestedArray/index.ts#L134
 
-get_dtype_asrtype <- function(dtype) {
-    # Reference: https://github.com/gzuidhof/zarr.js/blob/292804/src/nestedArray/types.ts#L32
-  DTYPE_RTYPE_MAPPING <- list(
-    "|b" = as.logical,
-    "|u1" = as.integer,
-    "|i1" = as.integer,
-    "<b" = as.logical,
-    "<u1" = as.integer,
-    "<i1" = as.integer,
-    "<u2" = as.integer,
-    "<i2" = as.integer,
-    "<u4" = as.integer,
-    "<i4" = as.integer,
-    "<f4" = as.double,
-    "<f8" = as.double,
-    ">b" = as.logical,
-    ">u1" = as.integer,
-    ">i1" = as.integer,
-    ">u2" = as.integer,
-    ">i2" = as.integer,
-    ">u4" = as.integer,
-    ">i4" = as.integer,
-    ">f4" = as.double,
-    ">f8" = as.double
-  )
-  return(DTYPE_RTYPE_MAPPING[[dtype]])
-  # TODO: handle errors
-  #stop('Dtype not recognized or not supported in pizzarr')
 }
 
+#' @keywords internal
 zero_based_to_one_based <- function(selection, shape) {
   selection_list <- list()
   for(i in seq_len(length(selection))) {
diff --git a/R/dtypes.R b/R/dtypes.R
new file mode 100644
index 0000000..3c526c2
--- /dev/null
+++ b/R/dtypes.R
@@ -0,0 +1,144 @@
+# Internal utility functions for converting between Zarr and R data types.
+
+
+#' @keywords internal
+get_dtype_rtype <- function(dtype) {
+    # Reference: https://github.com/gzuidhof/zarr.js/blob/292804/src/nestedArray/types.ts#L32
+  DTYPE_RTYPE_MAPPING <- list(
+    "|b" = logical(),
+    "|u1" = integer(),
+    "|i1" = integer(),
+    "<b" = logical(),
+    "<u1" = integer(),
+    "<i1" = integer(),
+    "<u2" = integer(),
+    "<i2" = integer(),
+    "<u4" = integer(),
+    "<i4" = integer(),
+    "<f4" = double(),
+    "<f8" = double(),
+    ">b" = logical(),
+    ">u1" = integer(),
+    ">i1" = integer(),
+    ">u2" = integer(),
+    ">i2" = integer(),
+    ">u4" = integer(),
+    ">i4" = integer(),
+    ">f4" = double(),
+    ">f8" = double()
+  )
+  return(DTYPE_RTYPE_MAPPING[[dtype]])
+  # TODO: handle errors
+  #stop('Dtype not recognized or not supported in pizzarr')
+}
+
+#' @keywords internal
+get_dtype_endianness <- function(dtype) {
+  # TODO: use regexes to figure this stuff out
+  DTYPE_ENDIANNESS_MAPPING <- list(
+    "|b" = "nr",
+    "|u1" = "nr",
+    "|i1" = "nr",
+    "<b" = "little",
+    "<u1" = "little",
+    "<i1" = "little",
+    "<u2" = "little",
+    "<i2" = "little",
+    "<u4" = "little",
+    "<i4" = "little",
+    "<f4" = "little",
+    "<f8" = "little",
+    ">b" = "big",
+    ">u1" = "big",
+    ">i1" = "big",
+    ">u2" = "big",
+    ">i2" = "big",
+    ">u4" = "big",
+    ">i4" = "big",
+    ">f4" = "big",
+    ">f8" = "big"
+  )
+  return(DTYPE_ENDIANNESS_MAPPING[[dtype]])
+}
+
+#' @keywords internal
+get_dtype_numbytes <- function(dtype) {
+  # TODO: use regexes to figure this stuff out
+  DTYPE_NUMBYTES_MAPPING <- list(
+    "|b" = 1,
+    "|u1" = 1,
+    "|i1" = 1,
+    "<b" = 1,
+    "<u1" = 1,
+    "<i1" = 1,
+    "<u2" = 2,
+    "<i2" = 2,
+    "<u4" = 4,
+    "<i4" = 4,
+    "<f4" = 4,
+    "<f8" = 8,
+    ">b" = 1,
+    ">u1" = 1,
+    ">i1" = 1,
+    ">u2" = 2,
+    ">i2" = 2,
+    ">u4" = 4,
+    ">i4" = 4,
+    ">f4" = 4,
+    ">f8" = 8
+  )
+  return(DTYPE_NUMBYTES_MAPPING[[dtype]])
+}
+
+#' @keywords internal
+get_dtype_from_array <- function(a) {
+  TYPEOF_RTYPE_MAPPING <- list(
+    "logical" = logical(),
+    "integer" = integer(),
+    "double" = double()
+  )
+  RTYPE_DTYPE_MAPPING <- list(
+    "logical" = "|b",
+    "integer" = "<i4",
+    "double" = "<f8"
+  )
+  rtype_str <- typeof(a)
+  return(RTYPE_DTYPE_MAPPING[[rtype_str]])
+}
+
+#' @keywords internal
+get_dtype_asrtype <- function(dtype) {
+    # Reference: https://github.com/gzuidhof/zarr.js/blob/292804/src/nestedArray/types.ts#L32
+  DTYPE_RTYPE_MAPPING <- list(
+    "|b" = as.logical,
+    "|u1" = as.integer,
+    "|i1" = as.integer,
+    "<b" = as.logical,
+    "<u1" = as.integer,
+    "<i1" = as.integer,
+    "<u2" = as.integer,
+    "<i2" = as.integer,
+    "<u4" = as.integer,
+    "<i4" = as.integer,
+    "<f4" = as.double,
+    "<f8" = as.double,
+    ">b" = as.logical,
+    ">u1" = as.integer,
+    ">i1" = as.integer,
+    ">u2" = as.integer,
+    ">i2" = as.integer,
+    ">u4" = as.integer,
+    ">i4" = as.integer,
+    ">f4" = as.double,
+    ">f8" = as.double
+  )
+  return(DTYPE_RTYPE_MAPPING[[dtype]])
+  # TODO: handle errors
+  #stop('Dtype not recognized or not supported in pizzarr')
+}
+
+#' @keywords internal
+get_typed_array_ctr <- function(dtype) {
+  rtype <- get_dtype_rtype(dtype)
+  return(function(dim) array(data = rtype, dim = dim))
+}
\ No newline at end of file