osm-p2p-db deletion batch ops

index.patch

index ec505de..ff29709 100644
--- a/index.js
+++ b/index.js
@@ -191,25 +191,13 @@ DB.prototype.del = function (key, opts, cb) {
 // OsmVersion, Opts -> [OsmBatchOp]
 DB.prototype._getDocumentDeletionBatchOps = function (key, opts, cb) {
   var self = this
-  self.kv.get(key, function (err, docs) {
+  self.kv.get(key, {fields: true}, function (err, docs) {
     if (err) return cb(err)
 
-    docs = mapObj(docs, function (version, value) {
-      if (value.deleted) {
-        return {
-          id: key,
-          version: version,
-          deleted: true
-        }
-      } else {
-        return value.value
-      }
-    })
-
-    var fields = {}
+    var fields = {v: opts.value || {}}
     var links = opts.keys || Object.keys(docs)
     links.forEach(function (ln) {
-      var v = docs[ln] || {}
+      var v = docs[ln].v || {}
       if (v.lat !== undefined && v.lon !== undefined) {
         if (!fields.points) fields.points = []
         fields.points.push({ lat: v.lat, lon: v.lon })
@@ -218,6 +206,10 @@ DB.prototype._getDocumentDeletionBatchOps = function (key, opts, cb) {
         if (!fields.refs) fields.refs = []
         fields.refs.push.apply(fields.refs, v.refs)
       }
+      if (fields.v.type && v.type !== fields.v.type) {
+        return cb(new Error('type mismatch')) // improve error desc.
+      }
+      fields.v.type = v.type
     })
     cb(null, [ { type: 'del', key: key, links: links, fields: fields } ])
   })