From dcbf8e83f609bd0b947126af15bd520a2a83c15e Mon Sep 17 00:00:00 2001
From: Tom Alexander <tom@fizz.buzz>
Date: Sat, 13 Jun 2020 19:55:40 -0400
Subject: [PATCH] Implement number casting.

---
 src/bin.rs                         | 17 ++++++++++++++++-
 src/renderer/parameters_context.rs | 19 ++++++++++++++++++-
 2 files changed, 34 insertions(+), 2 deletions(-)

diff --git a/src/bin.rs b/src/bin.rs
index 5c36944..fdde0a1 100644
--- a/src/bin.rs
+++ b/src/bin.rs
@@ -315,7 +315,22 @@ impl Loopable for serde_json::Value {
 
 impl Castable for serde_json::Value {
     fn cast_to_type<'a>(&'a self, target: &str) -> Option<IceResult<'a>> {
-        todo!()
+        match (self, target) {
+            (serde_json::Value::String(text), "number") => text
+                .parse::<u64>()
+                .map(|num| IceResult::from_owned(OwnedLiteral::LPositiveInteger(num)))
+                .or_else(|_| {
+                    text.parse::<i64>()
+                        .map(|num| IceResult::from_owned(OwnedLiteral::LNegativeInteger(num)))
+                })
+                .or_else(|_| {
+                    text.parse::<f64>()
+                        .map(|num| IceResult::from_owned(OwnedLiteral::LFloat(num)))
+                })
+                .ok(),
+            (serde_json::Value::Number(_), "number") => Some(IceResult::from_borrowed(self)),
+            (_, _) => panic!("Unimplemented cast"),
+        }
     }
 }
 
diff --git a/src/renderer/parameters_context.rs b/src/renderer/parameters_context.rs
index 026cf68..c1240b5 100644
--- a/src/renderer/parameters_context.rs
+++ b/src/renderer/parameters_context.rs
@@ -170,7 +170,24 @@ impl Walkable for OwnedLiteral {
 
 impl Castable for OwnedLiteral {
     fn cast_to_type<'a>(&'a self, target: &str) -> Option<IceResult<'a>> {
-        todo!()
+        match (self, target) {
+            (OwnedLiteral::LString(text), "number") => text
+                .parse::<u64>()
+                .map(|num| IceResult::from_owned(OwnedLiteral::LPositiveInteger(num)))
+                .or_else(|_| {
+                    text.parse::<i64>()
+                        .map(|num| IceResult::from_owned(OwnedLiteral::LNegativeInteger(num)))
+                })
+                .or_else(|_| {
+                    text.parse::<f64>()
+                        .map(|num| IceResult::from_owned(OwnedLiteral::LFloat(num)))
+                })
+                .ok(),
+            (OwnedLiteral::LPositiveInteger(_), "number") => Some(IceResult::from_borrowed(self)),
+            (OwnedLiteral::LNegativeInteger(_), "number") => Some(IceResult::from_borrowed(self)),
+            (OwnedLiteral::LFloat(_), "number") => Some(IceResult::from_borrowed(self)),
+            (_, _) => panic!("Unimplemented cast"),
+        }
     }
 }