Abstract GML data into custom Geometry type

Author: bartnv

src/main.rs

@@ -21,31 +21,38 @@ struct Column<'a> {
 
 struct Geometry {
   gtype: u8,
+  dims: u8,
   srid: u32,
-  num: u32,
-  pos: Vec<f64>
+  rings: Vec<Vec<f64>>
 }
-
-struct Ring {
-  pos: Vec<f64>
+impl Geometry {
+  fn new() -> Geometry {
+    Geometry { gtype: 0, dims: 2, srid: 4326, rings: Vec::new() }
+  }
+  fn reset(&mut self) {
+    self.gtype = 0;
+    self.dims = 2;
+    self.srid = 4326;
+    self.rings.clear();
+  }
 }
 
-fn gml_to_ewkb(value: &mut String, gmltype: u8, gmldims: u8, gmlsrid: u32, gmlrings: &Vec<Ring>) {
-  let mut ewkb = vec![1, gmltype, 0, 0];
-  let code = match gmldims {
+fn gml_to_ewkb(value: &mut String, geom: &Geometry) {
+  let mut ewkb = vec![1, geom.gtype, 0, 0];
+  let code = match geom.dims {
     2 => 32,
     3 => 32 | 128,
     _ => {
-      eprintln!("GML number of dimensions {} not supported", gmldims);
+      eprintln!("GML number of dimensions {} not supported", geom.dims);
       32
     }
   };
   ewkb.push(code);
-  ewkb.extend_from_slice(&gmlsrid.to_le_bytes());
-  ewkb.extend_from_slice(&(gmlrings.len() as u32).to_le_bytes());
-  for ring in gmlrings.iter() {
-    ewkb.extend_from_slice(&((ring.pos.len() as u32)/gmldims as u32).to_le_bytes());
-    for pos in ring.pos.iter() {
+  ewkb.extend_from_slice(&geom.srid.to_le_bytes());
+  ewkb.extend_from_slice(&(geom.rings.len() as u32).to_le_bytes());
+  for ring in geom.rings.iter() {
+    ewkb.extend_from_slice(&((ring.len() as u32)/geom.dims as u32).to_le_bytes());
+    for pos in ring.iter() {
       ewkb.extend_from_slice(&pos.to_le_bytes());
     }
   }
@@ -92,11 +99,8 @@ fn main() {
   let mut xmltotext = false;
   let mut text = String::new();
   let mut gmltoewkb = false;
-  let mut gmltype: u8 = 0;
-  let mut gmlsrid: u32 = 4326;
-  let mut gmlrings: Vec<Ring> = Vec::new();
-  let mut gmldims: u8 = 2;
   let mut gmlpos = false;
+  let mut gmlgeom = Geometry::new();
   let start = Instant::now();
   loop {
     match reader.read_event(&mut buf) {
@@ -120,14 +124,14 @@ fn main() {
                       value = value.split_off(i+2);
                     }
                     match value.parse::<u32>() {
-                      Ok(int) => gmlsrid = int,
+                      Ok(int) => gmlgeom.srid = int,
                       Err(_) => eprintln!("Invalid srsName {} in GML", value)
                     }
                   },
                   Ok("srsDimension") => {
                     let value = reader.decode(&attr.value).unwrap();
                     match value.parse::<u8>() {
-                      Ok(int) => gmldims = int,
+                      Ok(int) => gmlgeom.dims = int,
                       Err(_) => eprintln!("Invalid srsDimension {} in GML", value)
                     }
                   }
@@ -139,12 +143,12 @@ fn main() {
           match reader.decode(e.name()) {
             Err(_) => (),
             Ok(tag) => match tag {
-              "gml:Point" => gmltype = 1,
-              "gml:LineString" => gmltype = 2,
-              "gml:Polygon" => gmltype = 3,
+              "gml:Point" => gmlgeom.gtype = 1,
+              "gml:LineString" => gmlgeom.gtype = 2,
+              "gml:Polygon" => gmlgeom.gtype = 3,
               "gml:exterior" => (),
               "gml:interior" => (),
-              "gml:LinearRing" => gmlrings.push(Ring { pos: Vec::new() } ),
+              "gml:LinearRing" => gmlgeom.rings.push(Vec::new()),
               "gml:posList" => gmlpos = true,
               _ => eprintln!("GML type {} not supported", tag)
             }
@@ -177,7 +181,7 @@ fn main() {
           if gmlpos {
             let value = String::from(&e.unescape_and_decode(&reader).unwrap());
             for pos in value.split(' ') {
-              gmlrings.last_mut().unwrap().pos.push(pos.parse().unwrap());
+              gmlgeom.rings.last_mut().unwrap().push(pos.parse().unwrap());
             }
           }
           continue;
@@ -223,8 +227,8 @@ fn main() {
           for i in 0..columns.len() {
             if path == columns[i].path {
               gmltoewkb = false;
-              gml_to_ewkb(&mut columns[i].value, gmltype, gmldims, gmlsrid, &gmlrings);
-              gmlrings.clear();
+              gml_to_ewkb(&mut columns[i].value, &gmlgeom);
+              gmlgeom.reset();
               break;
             }
           }