parsers added

Author: aquatiko

src/parser.jl

@@ -0,0 +1,74 @@
+"""
+Parse input data and returns an Array and WCS object.
+"""
+function parse_input_data(input_data::ImageHDU)
+    return read(input_data), WCS.from_header(read_header(input_data, String))[1]
+end
+
+function parse_input_data(input_data::String, hdu_in = nothing)
+    return parse_input_data(FITS(input_data), hdu_in = hdu_in)
+end
+
+function parse_input_data(input_data::FITS, hdu_in = nothing)
+   if hdu_in == nothing
+        if length(input_data) > 1
+            throw(ArgumentError("More than one HDU is present, please specify HDU to use with ``hdu_in=`` option"))
+        else
+            hdu_in = 1
+        end
+    end
+    return parse_input_data(input_data[hdu_in])
+end
+
+function parse_input_data(input_data, hdu_in = nothing)
+    throw(TypeError(input_data, "should be in ", Union{String, FITS, ImageHDU, Tuple{ImageHDU,FITSHeader}}))
+end
+
+# TODO: extend support for passing FITSHeader when FITSHeader to WCSTransform support is possible.
+
+
+"""
+Parse output projection and returns a WCS object and Shape of output
+"""
+function parse_output_projection(output_projection::WCSTransform, shape_out = nothing)
+    wcs_out = output_projection
+    if shape_out isa nothing
+        throw(ArgumentError("Need to specify shape when specifying output_projection as WCS object"))
+    elseif length(shape_out) == 0
+        throw(DomainError(shape_out, "The shape of the output image should not be an empty tuple"))
+    end
+
+    return wcs_out, shape_out
+end
+
+function parse_output_projection(output_projection::ImageHDU, shape_out = nothing)
+    wcs_out = WCS.from_header(read_header(output_projection))[1]
+    if shape_out == nothing
+        shape_out = size(output_projection)
+    end
+    if length(shape_out) == 0
+        throw(DomainError(shape_out, "The shape of the output image should not be an empty tuple"))
+    end
+    return wcs_out, shape_out
+end
+
+function parse_output_projection(output_projection::String, hdu_number = nothing)
+    hdu_list = FITS(output_projection)
+    if hdu_number == nothing
+        wcs_out = WCS.from_header(read_header(hdu_list[1], String))
+    else
+        wcs_out = WCS.from_header(read_header(hdu_list[hdu_number], String))
+    end
+    
+    try
+        shape_out = size(output_projection)
+    catch
+        throw(ArgumentError("Given FITS file doesn't have ImageHDU"))
+    end
+    
+    return wcs_out, shape_out
+end
+
+function parse_output_projection(output_projection, shape_out = nothing)
+    throw(TypeError(output_projection, "should be in ", Union{String, WCSTransform, FITSHeader}))
+end