4 files changed, 203 insertions, 0 deletions
diff --git a/lib/src/types/datetime.rs b/lib/src/types/datetime.rs
new file mode 100644
index 0000000..00d739a
--- /dev/null
+++ b/lib/src/types/datetime.rs
@@ -0,0 +1,35 @@
+use std::convert::TryFrom;
+use anyhow::Error;
+use anyhow::Result;
+
+#[derive(Clone, Debug, Eq, PartialEq, serde::Serialize, serde::Deserialize)]
+#[serde(transparent)]
+pub struct DateTime(chrono::DateTime<chrono::Utc>);
+
+impl Into<ipfs::Ipld> for DateTime {
+    fn into(self) -> ipfs::Ipld {
+        ipfs::Ipld::String(self.0.to_rfc3339())
+    }
+}
+
+impl TryFrom<ipfs::Ipld> for DateTime {
+    type Error = Error;
+
+    fn try_from(ipld: ipfs::Ipld) -> Result<DateTime> {
+        match ipld {
+            ipfs::Ipld::String(s) => chrono::DateTime::parse_from_rfc3339(&s)
+                .map(|dt| dt.with_timezone(&chrono::Utc))
+                .map(DateTime)
+                .map_err(Error::from),
+            _ => anyhow::bail!("Expected string for timestamp"),
+        }
+    }
+}
+
+
+impl From<chrono::DateTime<chrono::Utc>> for DateTime {
+    fn from(dt: chrono::DateTime<chrono::Utc>) -> Self {
+        DateTime(dt)
+    }
+}
+
diff --git a/lib/src/types/mod.rs b/lib/src/types/mod.rs
new file mode 100644
index 0000000..7382f16
--- /dev/null
+++ b/lib/src/types/mod.rs
@@ -0,0 +1,8 @@
+mod node;
+pub use node::*;
+
+mod datetime;
+pub use datetime::*;
+
+mod payload;
+pub use payload::*;
diff --git a/lib/src/types/node.rs b/lib/src/types/node.rs
new file mode 100644
index 0000000..eb5679b
--- /dev/null
+++ b/lib/src/types/node.rs
@@ -0,0 +1,88 @@
+use anyhow::Result;
+
+use std::convert::TryFrom;
+
+#[derive(Debug, Eq, PartialEq, getset::Getters)]
+pub struct Node {
+    /// Version
+    #[getset(get = "pub")]
+    version: String,
+
+    /// Parent Nodes, identified by cid
+    parents: Vec<ipfs::Cid>,
+
+    /// The actual payload of the node, which is stored in another document identified by this cid
+    payload: ipfs::Cid,
+}
+
+impl Into<ipfs::Ipld> for Node {
+    fn into(self) -> ipfs::Ipld {
+        let mut map = std::collections::BTreeMap::new();
+        map.insert(String::from("version"), ipfs::Ipld::String(self.version));
+        map.insert(String::from("parents"), ipfs::Ipld::List(self.parents.into_iter().map(ipfs::Ipld::Link).collect()));
+        map.insert(String::from("payload"), ipfs::Ipld::Link(self.payload));
+        ipfs::Ipld::Map(map)
+    }
+}
+
+impl TryFrom<ipfs::Ipld> for Node {
+    type Error = anyhow::Error;
+
+    fn try_from(ipld: ipfs::Ipld) -> Result<Self> {
+        let missing_field = |name: &'static str| move || anyhow::anyhow!("Missing field {}", name);
+        let field_wrong_type = |name: &str, expty: &str| anyhow::bail!("Field {} has wrong type, expected {}", name, expty);
+        match ipld {
+            ipfs::Ipld::Map(map) => {
+                let version = match map.get("version").ok_or_else(missing_field("version"))? {
+                    ipfs::Ipld::String(s) => s.to_string(),
+                    _ => return field_wrong_type("version", "String")
+                };
+
+                let parents = match map.get("parents").ok_or_else(missing_field("parents"))? {
+                    ipfs::Ipld::List(s) => {
+                        s.into_iter()
+                            .map(|parent| -> Result<ipfs::Cid> {
+                                match parent {
+                                    ipfs::Ipld::Link(cid) => Ok(cid.clone()),
+                                    _ => anyhow::bail!("Field in parents has wrong type, expected Link"),
+                                }
+                            })
+                            .collect::<Result<Vec<ipfs::Cid>>>()?
+                    },
+                    _ => return field_wrong_type("parents", "Vec<Link>")
+                };
+
+                let payload = match map.get("payload").ok_or_else(missing_field("payload"))? {
+                    ipfs::Ipld::Link(cid) => cid.clone(),
+                    _ => return field_wrong_type("payload", "Link")
+                };
+
+                Ok(Node {
+                    version,
+                    parents,
+                    payload
+                })
+            }
+
+            _ => anyhow::bail!("Unexpected type, expected map")
+        }
+    }
+}
+
+impl Node {
+    pub fn new(version: String, parents: Vec<ipfs::Cid>, payload: ipfs::Cid) -> Self {
+        Self {
+            version,
+            parents,
+            payload,
+        }
+    }
+
+    pub fn parents(&self) -> Vec<ipfs::Cid> {
+        self.parents.clone()
+    }
+
+    pub fn payload(&self) -> ipfs::Cid {
+        self.payload.clone()
+    }
+}
diff --git a/lib/src/types/payload.rs b/lib/src/types/payload.rs
new file mode 100644
index 0000000..a11b215
--- /dev/null
+++ b/lib/src/types/payload.rs
@@ -0,0 +1,72 @@
+use std::convert::TryFrom;
+
+use anyhow::Result;
+
+use crate::types::DateTime;
+
+#[derive(Debug, Eq, PartialEq, getset::Getters)]
+pub struct Payload {
+    // TODO: Make this a mime::Mime, but as this type does not impl Serialize/Deserialize, we
+    // cannot do this trivially yet
+    #[getset(get = "pub")]
+    mime: String,
+
+    #[getset(get = "pub")]
+    timestamp: DateTime,
+
+    content: ipfs::Cid,
+}
+
+impl Into<ipfs::Ipld> for Payload {
+    fn into(self) -> ipfs::Ipld {
+        let mut map = std::collections::BTreeMap::new();
+        map.insert(String::from("mime"), ipfs::Ipld::String(self.mime));
+        map.insert(String::from("timestamp"), self.timestamp.into());
+        map.insert(String::from("content"), ipfs::Ipld::Link(self.content));
+        ipfs::Ipld::Map(map)
+    }
+}
+
+impl TryFrom<ipfs::Ipld> for Payload {
+    type Error = anyhow::Error;
+
+    fn try_from(ipld: ipfs::Ipld) -> Result<Self> {
+        let missing_field = |name: &'static str| move || anyhow::anyhow!("Missing field {}", name);
+        let field_wrong_type = |name: &str, expty: &str| anyhow::bail!("Field {} has wrong type, expected {}", name, expty);
+        match ipld {
+            ipfs::Ipld::Map(map) => {
+                let mime = match map.get("mime").ok_or_else(missing_field("mime"))? {
+                    ipfs::Ipld::String(s) => s.to_owned(),
+                    _ => return field_wrong_type("mime", "String")
+                };
+
+                let timestamp = map.get("timestamp")
+                    .ok_or_else(missing_field("timestamp"))?;
+                let timestamp = DateTime::try_from(timestamp.clone())?; // TODO dont clone
+
+                let content = match map.get("content").ok_or_else(missing_field("content"))? {
+                    ipfs::Ipld::Link(cid) => cid.clone(),
+                    _ => return field_wrong_type("content", "Link")
+                };
+
+                Ok(Payload {
+                    mime,
+                    timestamp,
+                    content
+                })
+            },
+
+            _ => anyhow::bail!("Unexpected type, expected map"),
+        }
+    }
+}
+
+impl Payload {
+    pub fn new(mime: String, timestamp: DateTime, content: ipfs::Cid) -> Self {
+        Self { mime, timestamp, content: content.into() }
+    }
+
+    pub fn content(&self) -> ipfs::Cid {
+        self.content.clone()
+    }
+}