Beginnings of JavaScript bindings

src/runtime/javascript/index.ts

@@ -0,0 +1,44 @@
+import { deref } from 'ref'
+import * as ref from 'ref'
+import * as ffi from 'ffi'
+
+const PgfDB = ref.types.int
+const PgfDBPtr = ref.refType(PgfDB)
+const PgfRevision = ref.types.int
+const PgfRevisionPtr = ref.refType(PgfRevision)
+const PgfExn = ref.types.int
+const PgfExnPtr = ref.refType(PgfExn)
+// const stringPtr = ref.refType(ref.types.CString)
+
+const PGF = ffi.Library('libpgf', {
+  'pgf_read_pgf': [ PgfDBPtr, [ 'string', PgfRevisionPtr, PgfExnPtr ] ],
+  'pgf_write_pgf': [ 'void', [ 'string', PgfDBPtr, PgfRevisionPtr, PgfExnPtr ] ],
+})
+
+interface Pointer extends Buffer {
+  deref(): any
+}
+
+interface State {
+  db: Pointer,
+  revision: number
+}
+const state: State = {
+  db: ref.NULL_POINTER as Pointer,
+  revision: 0
+}
+
+export default {
+  readPGF: function (path: string) {
+    const rev = ref.alloc(PgfRevision) as Pointer
+    const err = ref.alloc(PgfExn) as Pointer
+    const db = PGF.pgf_read_pgf(path, rev, err)
+    if (err.deref() === 0) {
+      state.db = db
+      state.revision = rev.deref()
+      console.log(`ok`)
+    } else {
+      console.error(`error ${err.deref()}`)
+    }
+  }
+}