Merge pull request #2 from twihno/main

feat: added support for grai 96

src/epc/grai.rs

@@ -0,0 +1,162 @@
+//! Global Returnable Asset Identifier
+//!
+//! This is a combination of a company prefix assigned by GS1, an asset type
+//! assigned by that company, and a serial number which allows an item to
+//! be uniquely identified.
+use crate::epc::{EPCValue, EPC};
+use crate::error::Result;
+use bitreader::BitReader;
+
+/// Metadata for a partition
+#[derive(Debug, PartialEq)]
+#[allow(dead_code)]
+struct Partition {
+    bits: u8,
+    digits: u8,
+}
+
+/// Decoded partition metadata
+#[derive(Debug, PartialEq)]
+struct GraiPartition {
+    company_prefix: Partition,
+    asset_type: Partition,
+}
+
+/// Get the number of bits and digits for the company prefix and the asset type based on the partition value.
+///
+/// Decoded according to Table 14-14 "GRAI Partition Table" in the GS1 EPC Tag Data Standard v2.1
+fn decode_partition_value(partition_value: u8) -> Result<GraiPartition> {
+    match partition_value {
+        0 => Ok(GraiPartition {
+            company_prefix: Partition {
+                bits: 40,
+                digits: 12,
+            },
+            asset_type: Partition { bits: 4, digits: 0 },
+        }),
+        1 => Ok(GraiPartition {
+            company_prefix: Partition {
+                bits: 37,
+                digits: 11,
+            },
+            asset_type: Partition { bits: 7, digits: 1 },
+        }),
+        2 => Ok(GraiPartition {
+            company_prefix: Partition {
+                bits: 34,
+                digits: 10,
+            },
+            asset_type: Partition {
+                bits: 10,
+                digits: 2,
+            },
+        }),
+        3 => Ok(GraiPartition {
+            company_prefix: Partition {
+                bits: 30,
+                digits: 9,
+            },
+            asset_type: Partition {
+                bits: 14,
+                digits: 3,
+            },
+        }),
+        4 => Ok(GraiPartition {
+            company_prefix: Partition {
+                bits: 27,
+                digits: 8,
+            },
+            asset_type: Partition {
+                bits: 17,
+                digits: 4,
+            },
+        }),
+        5 => Ok(GraiPartition {
+            company_prefix: Partition {
+                bits: 24,
+                digits: 7,
+            },
+            asset_type: Partition {
+                bits: 20,
+                digits: 5,
+            },
+        }),
+        6 => Ok(GraiPartition {
+            company_prefix: Partition {
+                bits: 20,
+                digits: 6,
+            },
+            asset_type: Partition {
+                bits: 24,
+                digits: 6,
+            },
+        }),
+        _ => Err("Invalid partition value".into()),
+    }
+}
+
+// EPC Header Filter Partition GS1
+// Company
+// Prefix
+// Asset Type Serial
+
+/// 96-bit Global Returnable Asset Identifier
+///
+/// This comprises a manager number, an object class, and a numeric serial
+/// number.
+#[derive(PartialEq, Debug)]
+pub struct GRAI96 {
+    /// Filter
+    pub filter: u8,
+    /// Partition
+    pub partition: u8,
+    /// GS1 Company Prefix
+    pub company_prefix: u64,
+    /// Asset type
+    pub asset_type: u32,
+    /// Serial number
+    pub serial: u64,
+}
+
+impl EPC for GRAI96 {
+    // GS1 EPC TDS section 14.6.4
+    fn to_uri(&self) -> String {
+        format!(
+            "urn:epc:id:grai:{}.{}.{}",
+            self.company_prefix, self.asset_type, self.serial
+        )
+    }
+
+    fn to_tag_uri(&self) -> String {
+        format!(
+            "urn:epc:tag:grai-96:{}.{}.{}.{}",
+            self.filter, self.company_prefix, self.asset_type, self.serial
+        )
+    }
+
+    fn get_value(&self) -> EPCValue {
+        EPCValue::GRAI96(self)
+    }
+}
+
+// GS1 EPC TDS Section 14.6.4
+pub fn decode_grai96(data: &[u8]) -> Result<Box<dyn EPC>> {
+    let mut reader = BitReader::new(data);
+
+    let filter = reader.read_u8(3)?;
+    let partition = reader.read_u8(3)?;
+
+    let grai_partition = decode_partition_value(partition)?;
+
+    let company_prefix = reader.read_u64(grai_partition.company_prefix.bits)?;
+    let asset_type = reader.read_u32(grai_partition.asset_type.bits)?;
+    let serial = reader.read_u64(38)?;
+
+    Ok(Box::new(GRAI96 {
+        filter,
+        partition,
+        company_prefix,
+        asset_type,
+        serial,
+    }))
+}

src/epc/mod.rs

@@ -8,6 +8,7 @@ use num_enum::TryFromPrimitive;
 use std::convert::TryFrom;
 
 pub mod gid;
+pub mod grai;
 pub mod sgtin;
 pub mod sscc;
 pub mod tid;
@@ -87,6 +88,7 @@ pub enum EPCValue<'a> {
     SGTIN198(&'a sgtin::SGTIN198),
     SSCC96(&'a sscc::SSCC96),
     GID96(&'a gid::GID96),
+    GRAI96(&'a grai::GRAI96),
 }
 
 fn take_header(data: &[u8]) -> Result<(&[u8], EPCBinaryHeader)> {
@@ -100,6 +102,7 @@ pub fn decode_binary(data: &[u8]) -> Result<Box<dyn EPC>> {
 
     Ok(match header {
         EPCBinaryHeader::GID96 => gid::decode_gid96(data)?,
+        EPCBinaryHeader::GRAI96 => grai::decode_grai96(data)?,
         EPCBinaryHeader::SGITN96 => sgtin::decode_sgtin96(data)?,
         EPCBinaryHeader::SGITN198 => sgtin::decode_sgtin198(data)?,
         EPCBinaryHeader::SSCC96 => sscc::decode_sscc96(data)?,

tests/test_epc.rs

@@ -121,4 +121,12 @@ fn test_examples() {
     let data = decode_binary(&hex::decode("3500E86F8000A9E000000586").unwrap()).unwrap();
     assert_eq!(data.to_uri(), "urn:epc:id:gid:952056.2718.1414");
     assert_eq!(data.to_tag_uri(), "urn:epc:tag:gid-96:952056.2718.1414");
+
+    // GRAI-96
+    let data = decode_binary(&hex::decode("3376451FD40C0E400000162E").unwrap()).unwrap();
+    assert_eq!(data.to_uri(), "urn:epc:id:grai:9521141.12345.5678");
+    assert_eq!(
+        data.to_tag_uri(),
+        "urn:epc:tag:grai-96:3.9521141.12345.5678"
+    );
 }