automerge/automerge-wasm/README.md
2022-01-31 15:23:46 -05:00

24 KiB

Automerge WASM Low Level Interface

This is a low level automerge library written in rust exporting a javascript API via WASM. This low level api is the underpinning to the automerge-js library that reimplements the Automerge API via these low level functions.

Static Functions

Methods

doc.clone(actor?: string) : Make a complete

doc.free() : deallocate WASM memory associated with a document

#[wasm_bindgen] pub fn free(self) {}

#[wasm_bindgen(js_name = pendingOps)]
pub fn pending_ops(&self) -> JsValue {
    (self.0.pending_ops() as u32).into()
}

pub fn commit(&mut self, message: Option<String>, time: Option<f64>) -> Array {
    let heads = self.0.commit(message, time.map(|n| n as i64));
    let heads: Array = heads
        .iter()
        .map(|h| JsValue::from_str(&hex::encode(&h.0)))
        .collect();
    heads
}

pub fn rollback(&mut self) -> f64 {
    self.0.rollback() as f64
}

pub fn keys(&mut self, obj: String, heads: Option<Array>) -> Result<Array, JsValue> {
    let obj = self.import(obj)?;
    let result = if let Some(heads) = get_heads(heads) {
        self.0.keys_at(&obj, &heads)
    } else {
        self.0.keys(&obj)
    }
    .iter()
    .map(|s| JsValue::from_str(s))
    .collect();
    Ok(result)
}

pub fn text(&mut self, obj: String, heads: Option<Array>) -> Result<String, JsValue> {
    let obj = self.import(obj)?;
    if let Some(heads) = get_heads(heads) {
        self.0.text_at(&obj, &heads)
    } else {
        self.0.text(&obj)
    }
    .map_err(to_js_err)
}

pub fn splice(
    &mut self,
    obj: String,
    start: f64,
    delete_count: f64,
    text: JsValue,
) -> Result<Option<Array>, JsValue> {
    let obj = self.import(obj)?;
    let start = start as usize;
    let delete_count = delete_count as usize;
    let mut vals = vec![];
    if let Some(t) = text.as_string() {
        self.0
            .splice_text(&obj, start, delete_count, &t)
            .map_err(to_js_err)?;
        Ok(None)
    } else {
        if let Ok(array) = text.dyn_into::<Array>() {
            for i in array.iter() {
                if let Ok(array) = i.clone().dyn_into::<Array>() {
                    let value = array.get(1);
                    let datatype = array.get(2);
                    let value = self.import_value(value, datatype.as_string())?;
                    vals.push(value);
                } else {
                    let value = self.import_value(i, None)?;
                    vals.push(value);
                }
            }
        }
        let result = self
            .0
            .splice(&obj, start, delete_count, vals)
            .map_err(to_js_err)?;
        if result.is_empty() {
            Ok(None)
        } else {
            let result: Array = result
                .iter()
                .map(|r| JsValue::from(r.to_string()))
                .collect();
            Ok(result.into())
        }
    }
}

pub fn push(
    &mut self,
    obj: String,
    value: JsValue,
    datatype: Option<String>,
) -> Result<Option<String>, JsValue> {
    let obj = self.import(obj)?;
    let value = self.import_value(value, datatype)?;
    let index = self.0.length(&obj);
    let opid = self.0.insert(&obj, index, value).map_err(to_js_err)?;
    Ok(opid.map(|id| id.to_string()))
}

pub fn insert(
    &mut self,
    obj: String,
    index: f64,
    value: JsValue,
    datatype: Option<String>,
) -> Result<Option<String>, JsValue> {
    let obj = self.import(obj)?;
    let index = index as f64;
    let value = self.import_value(value, datatype)?;
    let opid = self
        .0
        .insert(&obj, index as usize, value)
        .map_err(to_js_err)?;
    Ok(opid.map(|id| id.to_string()))
}

pub fn set(
    &mut self,
    obj: String,
    prop: JsValue,
    value: JsValue,
    datatype: Option<String>,
) -> Result<Option<String>, JsValue> {
    let obj = self.import(obj)?;
    let prop = self.import_prop(prop)?;
    let value = self.import_value(value, datatype)?;
    let opid = self.0.set(&obj, prop, value).map_err(to_js_err)?;
    Ok(opid.map(|id| id.to_string()))
}

pub fn make(
    &mut self,
    obj: String,
    prop: JsValue,
    value: JsValue,
) -> Result<String, JsValue> {
    let obj = self.import(obj)?;
    let prop = self.import_prop(prop)?;
    let value = self.import_value(value, None)?;
    if value.is_object() {
      let opid = self.0.set(&obj, prop, value).map_err(to_js_err)?;
      Ok(opid.unwrap().to_string())
    } else {
      Err("invalid object type".into())
    }
}

pub fn inc(&mut self, obj: String, prop: JsValue, value: JsValue) -> Result<(), JsValue> {
    let obj = self.import(obj)?;
    let prop = self.import_prop(prop)?;
    let value: f64 = value
        .as_f64()
        .ok_or("inc needs a numberic value")
        .map_err(to_js_err)?;
    self.0.inc(&obj, prop, value as i64).map_err(to_js_err)?;
    Ok(())
}

pub fn value(
    &mut self,
    obj: String,
    prop: JsValue,
    heads: Option<Array>,
) -> Result<Array, JsValue> {
    let obj = self.import(obj)?;
    let result = Array::new();
    let prop = to_prop(prop);
    let heads = get_heads(heads);
    if let Ok(prop) = prop {
        let value = if let Some(h) = heads {
            self.0.value_at(&obj, prop, &h)
        } else {
            self.0.value(&obj, prop)
        }
        .map_err(to_js_err)?;
        match value {
            Some((Value::Object(obj_type), obj_id)) => {
                result.push(&obj_type.to_string().into());
                result.push(&obj_id.to_string().into());
            }
            Some((Value::Scalar(value), _)) => {
                result.push(&datatype(&value).into());
                result.push(&ScalarValue(value).into());
            }
            None => {}
        }
    }
    Ok(result)
}

pub fn values(
    &mut self,
    obj: String,
    arg: JsValue,
    heads: Option<Array>,
) -> Result<Array, JsValue> {
    let obj = self.import(obj)?;
    let result = Array::new();
    let prop = to_prop(arg);
    if let Ok(prop) = prop {
        let values = if let Some(heads) = get_heads(heads) {
            self.0.values_at(&obj, prop, &heads)
        } else {
            self.0.values(&obj, prop)
        }
        .map_err(to_js_err)?;
        for value in values {
            match value {
                (Value::Object(obj_type), obj_id) => {
                    let sub = Array::new();
                    sub.push(&obj_type.to_string().into());
                    sub.push(&obj_id.to_string().into());
                    result.push(&sub.into());
                }
                (Value::Scalar(value), id) => {
                    let sub = Array::new();
                    sub.push(&datatype(&value).into());
                    sub.push(&ScalarValue(value).into());
                    sub.push(&id.to_string().into());
                    result.push(&sub.into());
                }
            }
        }
    }
    Ok(result)
}

pub fn length(&mut self, obj: String, heads: Option<Array>) -> Result<f64, JsValue> {
    let obj = self.import(obj)?;
    if let Some(heads) = get_heads(heads) {
        Ok(self.0.length_at(&obj, &heads) as f64)
    } else {
        Ok(self.0.length(&obj) as f64)
    }
}

pub fn del(&mut self, obj: String, prop: JsValue) -> Result<(), JsValue> {
    let obj = self.import(obj)?;
    let prop = to_prop(prop)?;
    self.0.del(&obj, prop).map_err(to_js_err)?;
    Ok(())
}

pub fn mark(
    &mut self,
    obj: JsValue,
    range: JsValue,
    name: JsValue,
    value: JsValue,
    datatype: JsValue,
) -> Result<(), JsValue> {
    let obj = self.import(obj)?;
    let re = Regex::new(r"([\[\(])(\d+)\.\.(\d+)([\)\]])").unwrap();
    let range = range.as_string().ok_or("range must be a string")?;
    let cap = re.captures_iter(&range).next().ok_or("range must be in the form of (start..end] or [start..end) etc... () for sticky, [] for normal")?;
    let start: usize = cap[2].parse().map_err(|_| to_js_err("invalid start"))?;
    let end: usize = cap[3].parse().map_err(|_| to_js_err("invalid end"))?;
    let start_sticky = &cap[1] == "(";
    let end_sticky = &cap[4] == ")";
    let name = name
        .as_string()
        .ok_or("invalid mark name")
        .map_err(to_js_err)?;
    let value = self.import_scalar(&value, datatype.as_string())?;
    self.0
        .mark(&obj, start, start_sticky, end, end_sticky, &name, value)
        .map_err(to_js_err)?;
    Ok(())
}

pub fn spans(&mut self, obj: JsValue) -> Result<JsValue, JsValue> {
    let obj = self.import(obj)?;
    let text = self.0.text(&obj).map_err(to_js_err)?;
    let spans = self.0.spans(&obj).map_err(to_js_err)?;
    let mut last_pos = 0;
    let result = Array::new();
    for s in spans {
        let marks = Array::new();
        for m in s.marks {
            let mark = Array::new();
            mark.push(&m.0.into());
            mark.push(&datatype(&m.1).into());
            mark.push(&ScalarValue(m.1).into());
            marks.push(&mark.into());
        }
        let text_span = &text[last_pos..s.pos]; //.slice(last_pos, s.pos);
        if text_span.len() > 0 {
            result.push(&text_span.into());
        }
        result.push(&marks);
        last_pos = s.pos;
        //let obj = Object::new().into();
        //js_set(&obj, "pos", s.pos as i32)?;
        //js_set(&obj, "marks", marks)?;
        //result.push(&obj.into());
    }
    let text_span = &text[last_pos..];
    if text_span.len() > 0 {
        result.push(&text_span.into());
    }
    Ok(result.into())
}

pub fn save(&mut self) -> Result<Uint8Array, JsValue> {
    self.0
        .save()
        .map(|v| Uint8Array::from(v.as_slice()))
        .map_err(to_js_err)
}

#[wasm_bindgen(js_name = saveIncremental)]
pub fn save_incremental(&mut self) -> Uint8Array {
    let bytes = self.0.save_incremental();
    Uint8Array::from(bytes.as_slice())
}

#[wasm_bindgen(js_name = loadIncremental)]
pub fn load_incremental(&mut self, data: Uint8Array) -> Result<f64, JsValue> {
    let data = data.to_vec();
    let len = self.0.load_incremental(&data).map_err(to_js_err)?;
    Ok(len as f64)
}

#[wasm_bindgen(js_name = applyChanges)]
pub fn apply_changes(&mut self, changes: JsValue) -> Result<(), JsValue> {
    let changes: Vec<_> = JS(changes).try_into()?;
    self.0.apply_changes(&changes).map_err(to_js_err)?;
    Ok(())
}

#[wasm_bindgen(js_name = getChanges)]
pub fn get_changes(&mut self, have_deps: JsValue) -> Result<Array, JsValue> {
    let deps: Vec<_> = JS(have_deps).try_into()?;
    let changes = self.0.get_changes(&deps);
    let changes: Array = changes
        .iter()
        .map(|c| Uint8Array::from(c.raw_bytes()))
        .collect();
    Ok(changes)
}

#[wasm_bindgen(js_name = getChangesAdded)]
pub fn get_changes_added(&mut self, other: &Automerge) -> Result<Array, JsValue> {
    let changes = self.0.get_changes_added(&other.0);
    let changes: Array = changes
        .iter()
        .map(|c| Uint8Array::from(c.raw_bytes()))
        .collect();
    Ok(changes)
}

#[wasm_bindgen(js_name = getHeads)]
pub fn get_heads(&mut self) -> Array {
    let heads = self.0.get_heads();
    let heads: Array = heads
        .iter()
        .map(|h| JsValue::from_str(&hex::encode(&h.0)))
        .collect();
    heads
}

#[wasm_bindgen(js_name = getActorId)]
pub fn get_actor_id(&mut self) -> String {
    let actor = self.0.get_actor();
    actor.to_string()
}

#[wasm_bindgen(js_name = getLastLocalChange)]
pub fn get_last_local_change(&mut self) -> Result<Option<Uint8Array>, JsValue> {
    if let Some(change) = self.0.get_last_local_change() {
        Ok(Some(Uint8Array::from(change.raw_bytes())))
    } else {
        Ok(None)
    }
}

pub fn dump(&self) {
    self.0.dump()
}

#[wasm_bindgen(js_name = getMissingDeps)]
pub fn get_missing_deps(&mut self, heads: Option<Array>) -> Result<Array, JsValue> {
    let heads = get_heads(heads).unwrap_or_default();
    let deps = self.0.get_missing_deps(&heads);
    let deps: Array = deps
        .iter()
        .map(|h| JsValue::from_str(&hex::encode(&h.0)))
        .collect();
    Ok(deps)
}

#[wasm_bindgen(js_name = receiveSyncMessage)]
pub fn receive_sync_message(
    &mut self,
    state: &mut SyncState,
    message: Uint8Array,
) -> Result<(), JsValue> {
    let message = message.to_vec();
    let message = am::SyncMessage::decode(message.as_slice()).map_err(to_js_err)?;
    self.0
        .receive_sync_message(&mut state.0, message)
        .map_err(to_js_err)?;
    Ok(())
}

#[wasm_bindgen(js_name = generateSyncMessage)]
pub fn generate_sync_message(&mut self, state: &mut SyncState) -> Result<JsValue, JsValue> {
    if let Some(message) = self.0.generate_sync_message(&mut state.0) {
        Ok(Uint8Array::from(message.encode().map_err(to_js_err)?.as_slice()).into())
    } else {
        Ok(JsValue::null())
    }
}

#[wasm_bindgen(js_name = toJS)]
pub fn to_js(&self) -> JsValue {
    map_to_js(&self.0, &ROOT)
}

fn import(&self, id: String) -> Result<ObjId, JsValue> {
    self.0.import(&id).map_err(to_js_err)
}

fn import_prop(&mut self, prop: JsValue) -> Result<Prop, JsValue> {
    if let Some(s) = prop.as_string() {
        Ok(s.into())
    } else if let Some(n) = prop.as_f64() {
        Ok((n as usize).into())
    } else {
        Err(format!("invalid prop {:?}", prop).into())
    }
}

fn import_scalar(
    &mut self,
    value: &JsValue,
    datatype: Option<String>,
) -> Result<am::ScalarValue, JsValue> {
    match datatype.as_deref() {
        Some("boolean") => value
            .as_bool()
            .ok_or_else(|| "value must be a bool".into())
            .map(am::ScalarValue::Boolean),
        Some("int") => value
            .as_f64()
            .ok_or_else(|| "value must be a number".into())
            .map(|v| am::ScalarValue::Int(v as i64)),
        Some("uint") => value
            .as_f64()
            .ok_or_else(|| "value must be a number".into())
            .map(|v| am::ScalarValue::Uint(v as u64)),
        Some("f64") => value
            .as_f64()
            .ok_or_else(|| "value must be a number".into())
            .map(am::ScalarValue::F64),
        Some("bytes") => Ok(am::ScalarValue::Bytes(
            value.clone().dyn_into::<Uint8Array>().unwrap().to_vec(),
        )),
        Some("counter") => value
            .as_f64()
            .ok_or_else(|| "value must be a number".into())
            .map(|v| am::ScalarValue::counter(v as i64)),
        Some("timestamp") => value
            .as_f64()
            .ok_or_else(|| "value must be a number".into())
            .map(|v| am::ScalarValue::Timestamp(v as i64)),
        /*
        Some("bytes") => unimplemented!(),
        Some("cursor") => unimplemented!(),
        */
        Some("null") => Ok(am::ScalarValue::Null),
        Some(_) => Err(format!("unknown datatype {:?}", datatype).into()),
        None => {
            if value.is_null() {
                Ok(am::ScalarValue::Null)
            } else if let Some(b) = value.as_bool() {
                Ok(am::ScalarValue::Boolean(b))
            } else if let Some(s) = value.as_string() {
                // FIXME - we need to detect str vs int vs float vs bool here :/
                Ok(am::ScalarValue::Str(s.into()))
            } else if let Some(n) = value.as_f64() {
                if (n.round() - n).abs() < f64::EPSILON {
                    Ok(am::ScalarValue::Int(n as i64))
                } else {
                    Ok(am::ScalarValue::F64(n))
                }
            //                } else if let Some(o) = to_objtype(&value) {
            //                    Ok(o.into())
            } else if let Ok(d) = value.clone().dyn_into::<js_sys::Date>() {
                Ok(am::ScalarValue::Timestamp(d.get_time() as i64))
            } else if let Ok(o) = &value.clone().dyn_into::<Uint8Array>() {
                Ok(am::ScalarValue::Bytes(o.to_vec()))
            } else {
                Err("value is invalid".into())
            }
        }
    }
}

fn import_value(&mut self, value: JsValue, datatype: Option<String>) -> Result<Value, JsValue> {
    match self.import_scalar(&value, datatype) {
        Ok(val) => Ok(val.into()),
        Err(err) => {
            if let Some(o) = to_objtype(&value) {
                Ok(o.into())
            } else {
                Err(err)
            }
        }
    }
    /*
    match datatype.as_deref() {
        Some("boolean") => value
            .as_bool()
            .ok_or_else(|| "value must be a bool".into())
            .map(|v| am::ScalarValue::Boolean(v).into()),
        Some("int") => value
            .as_f64()
            .ok_or_else(|| "value must be a number".into())
            .map(|v| am::ScalarValue::Int(v as i64).into()),
        Some("uint") => value
            .as_f64()
            .ok_or_else(|| "value must be a number".into())
            .map(|v| am::ScalarValue::Uint(v as u64).into()),
        Some("f64") => value
            .as_f64()
            .ok_or_else(|| "value must be a number".into())
            .map(|n| am::ScalarValue::F64(n).into()),
        Some("bytes") => {
            Ok(am::ScalarValue::Bytes(value.dyn_into::<Uint8Array>().unwrap().to_vec()).into())
        }
        Some("counter") => value
            .as_f64()
            .ok_or_else(|| "value must be a number".into())
            .map(|v| am::ScalarValue::counter(v as i64).into()),
        Some("timestamp") => value
            .as_f64()
            .ok_or_else(|| "value must be a number".into())
            .map(|v| am::ScalarValue::Timestamp(v as i64).into()),
        Some("null") => Ok(am::ScalarValue::Null.into()),
        Some(_) => Err(format!("unknown datatype {:?}", datatype).into()),
        None => {
            if value.is_null() {
                Ok(am::ScalarValue::Null.into())
            } else if let Some(b) = value.as_bool() {
                Ok(am::ScalarValue::Boolean(b).into())
            } else if let Some(s) = value.as_string() {
                // FIXME - we need to detect str vs int vs float vs bool here :/
                Ok(am::ScalarValue::Str(s.into()).into())
            } else if let Some(n) = value.as_f64() {
                if (n.round() - n).abs() < f64::EPSILON {
                    Ok(am::ScalarValue::Int(n as i64).into())
                } else {
                    Ok(am::ScalarValue::F64(n).into())
                }
            } else if let Some(o) = to_objtype(&value) {
                Ok(o.into())
            } else if let Ok(d) = value.clone().dyn_into::<js_sys::Date>() {
                Ok(am::ScalarValue::Timestamp(d.get_time() as i64).into())
            } else if let Ok(o) = &value.dyn_into::<Uint8Array>() {
                Ok(am::ScalarValue::Bytes(o.to_vec()).into())
            } else {
                Err("value is invalid".into())
            }
        }
    }
    */
}

}

#[wasm_bindgen(js_name = create)] pub fn init(actor: Option) -> Result<Automerge, JsValue> { console_error_panic_hook::set_once(); Automerge::new(actor) }

#[wasm_bindgen(js_name = loadDoc)] pub fn load(data: Uint8Array, actor: Option) -> Result<Automerge, JsValue> { let data = data.to_vec(); let mut automerge = am::Automerge::load(&data).map_err(to_js_err)?; if let Some(s) = actor { let actor = automerge::ActorId::from(hex::decode(s).map_err(to_js_err)?.to_vec()); automerge.set_actor(actor) } Ok(Automerge(automerge)) }

#[wasm_bindgen(js_name = encodeChange)] pub fn encode_change(change: JsValue) -> Result<Uint8Array, JsValue> { let change: am::ExpandedChange = change.into_serde().map_err(to_js_err)?; let change: Change = change.into(); Ok(Uint8Array::from(change.raw_bytes())) }

#[wasm_bindgen(js_name = decodeChange)] pub fn decode_change(change: Uint8Array) -> Result<JsValue, JsValue> { let change = Change::from_bytes(change.to_vec()).map_err(to_js_err)?; let change: am::ExpandedChange = change.decode(); JsValue::from_serde(&change).map_err(to_js_err) }

#[wasm_bindgen(js_name = initSyncState)] pub fn init_sync_state() -> SyncState { SyncState(am::SyncState::new()) }

// this is needed to be compatible with the automerge-js api #[wasm_bindgen(js_name = importSyncState)] pub fn import_sync_state(state: JsValue) -> Result<SyncState, JsValue> { Ok(SyncState(JS(state).try_into()?)) }

// this is needed to be compatible with the automerge-js api #[wasm_bindgen(js_name = exportSyncState)] pub fn export_sync_state(state: SyncState) -> JsValue { JS::from(state.0).into() }

#[wasm_bindgen(js_name = encodeSyncMessage)] pub fn encode_sync_message(message: JsValue) -> Result<Uint8Array, JsValue> { let heads = js_get(&message, "heads")?.try_into()?; let need = js_get(&message, "need")?.try_into()?; let changes = js_get(&message, "changes")?.try_into()?; let have = js_get(&message, "have")?.try_into()?; Ok(Uint8Array::from( am::SyncMessage { heads, need, have, changes, } .encode() .unwrap() .as_slice(), )) }

#[wasm_bindgen(js_name = decodeSyncMessage)] pub fn decode_sync_message(msg: Uint8Array) -> Result<JsValue, JsValue> { let data = msg.to_vec(); let msg = am::SyncMessage::decode(&data).map_err(to_js_err)?; let heads = AR::from(msg.heads.as_slice()); let need = AR::from(msg.need.as_slice()); let changes = AR::from(msg.changes.as_slice()); let have = AR::from(msg.have.as_slice()); let obj = Object::new().into(); js_set(&obj, "heads", heads)?; js_set(&obj, "need", need)?; js_set(&obj, "have", have)?; js_set(&obj, "changes", changes)?; Ok(obj) }

#[wasm_bindgen(js_name = encodeSyncState)] pub fn encode_sync_state(state: SyncState) -> Result<Uint8Array, JsValue> { let state = state.0; Ok(Uint8Array::from( state.encode().map_err(to_js_err)?.as_slice(), )) }

#[wasm_bindgen(js_name = decodeSyncState)] pub fn decode_sync_state(data: Uint8Array) -> Result<SyncState, JsValue> { SyncState::decode(data) }

#[wasm_bindgen(js_name = MAP)] pub struct Map {}

#[wasm_bindgen(js_name = LIST)] pub struct List {}

#[wasm_bindgen(js_name = TEXT)] pub struct Text {}

#[wasm_bindgen(js_name = TABLE)] pub struct Table {}