More cleanup, seemingly reading timestamp headers now

src/file.jl

@@ -33,6 +33,7 @@ Contains the header byte for a record row
 mutable struct RecordHeader
     type::RecordType
     local_mesg_type::Int64
+    time_offset::Union{Nothing, Int64}
 end
 
 struct FieldDefinition
@@ -48,6 +49,16 @@ mutable struct DefinitionBody
     field_definitions::Vector{FieldDefinition}
 end
 
+"""
+    LocalMesgTypeMapping
+
+For use in mapping local message type to a struct containing useful info.
+"""
+struct LocalMesgTypeMapping
+    row_sz::Int64
+    global_mesg_type::AbstractString
+end
+
 mutable struct DataBody
 end
 
@@ -67,7 +78,7 @@ mutable struct FITFileReader
     bytes_read::Int64
     header::Union{FITHeader, Nothing}
     body::Union{Vector{DataRecord}, Nothing}
-    mesg_map::Dict{Real, AbstractString}
+    mesg_map::Dict{Real, LocalMesgTypeMapping}
     next_row_sz::Int64
 end
 
@@ -128,16 +139,22 @@ end
 Decode the header byte, determine if the record is a definition, data, or timestamp.
 """
 function decode_header(v::Vector{UInt8})::RecordHeader
-    type = if v[7] == 1
-        timestamp
-    elseif v[6] == 1
+    type = if v[8] == 1
+        timestamp 
+    elseif v[7] == 1
         definition
     else
         data
     end
 
-    local_mesg_type = sum_bits(v[1:4])
-    RecordHeader(type, local_mesg_type)
+    if type == timestamp
+        local_mesg_type = sum_bits(v[6:7])
+        time_offset = sum_bits(v[1:5])
+        RecordHeader(type, local_mesg_type, time_offset)
+    else
+        local_mesg_type = sum_bits(v[1:4])
+        RecordHeader(type, local_mesg_type, nothing)
+    end
 end
 
 """
@@ -165,7 +182,7 @@ Using f, read the appropriate message body given the hdr (which tells us if this
 """
 function read_record_content!(f::FITFileReader, hdr::RecordHeader)::Union{DefinitionBody, DataBody}
     # Read the definition record, return the body
-    if hdr.definition
+    if hdr.type == definition
         # Read all bytes first
         header_bytes = read_bytes!(f, 5)
         header_field_definitions = read_bytes!(f, header_bytes[end] * 3) # sz * field size 
@@ -185,8 +202,7 @@ function read_record_content!(f::FITFileReader, hdr::RecordHeader)::Union{Defini
         row_sz = sum(get_row_size.([field_definitions, developer_field_definitions]))
 
         # Associate the global message type with this local message type.
-        f.mesg_map[hdr.local_mesg_type] = global_mesg_type
-        f.next_row_sz = row_sz
+        f.mesg_map[hdr.local_mesg_type] = LocalMesgTypeMapping(row_sz, global_mesg_type)
 
         DefinitionBody(
             header_bytes[2] == 0 ? "littleendian" : "bigendian",