restructuring and WIP

src/vcd/types.rs

@@ -0,0 +1,59 @@
+use std::collections::BTreeMap;
+use chrono::prelude::*;
+use num::BigInt;
+
+#[derive(Debug)]
+struct Version(String);
+
+#[derive(Debug)]
+enum Timescale {ps, ns, us, ms, s, unit}
+
+#[derive(Debug)]
+pub(super) struct Metadata {
+    date      : Option<DateTime<Utc>>,
+    version   : Option<Version>,
+    timescale : (Option<u32>, Timescale)}
+
+#[derive(Debug)]
+struct Scope_Idx(usize);
+
+#[derive(Debug)]
+struct Signal_Idx(usize);
+
+#[derive(Debug)]
+enum SignalGeneric{
+    Signal{
+        name           : String,
+        timeline       : BTreeMap<BigInt, BigInt>,
+        scope_parent   : Scope_Idx},
+    SignalAlias{
+        name          : String,
+        signal_alias  : Signal_Idx}
+}
+
+#[derive(Debug)]
+struct Scope {
+    name          : String,
+    child_signals : Vec<Signal_Idx>,
+    child_scopes  : Vec<Scope_Idx>}
+
+
+#[derive(Debug)]
+struct VCD {
+    metadata    : Metadata,
+    all_signals : Vec<SignalGeneric>,
+    // the root scope should always be placed at index 0
+    all_scopes  : Vec<Scope>}
+
+impl VCD {
+    pub fn new() -> Self {
+        let metadata = Metadata {
+            date      : None,
+            version   : None,
+            timescale : (None, Timescale::unit)};
+        VCD {
+            metadata    : metadata,
+            all_signals : Vec::<SignalGeneric>::new(),
+            all_scopes  : Vec::<Scope>::new()}
+        }
+    }