WIP: JSONjsonld

5 files changed, 759 insertions, 5 deletions

diff --git a/src/jsonld.c b/src/jsonld.c
new file mode 100644
index 00000000..f5d4c81a
--- /dev/null
+++ b/src/jsonld.c
@@ -0,0 +1,741 @@
+/*
+  Copyright 2011-2017 David Robillard <http://drobilla.net>
+
+  Permission to use, copy, modify, and/or distribute this software for any
+  purpose with or without fee is hereby granted, provided that the above
+  copyright notice and this permission notice appear in all copies.
+
+  THIS SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
+  WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
+  MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
+  ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
+  WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
+  ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
+  OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
+*/
+
+#include "serd_internal.h"
+
+#include "reader.h"
+
+static SerdStatus read_object(SerdReader* reader,
+                              ReadContext ctx,
+                              Ref*        dest,
+                              Ref*        datatype,
+                              Ref*        lang);
+
+static SerdStatus read_array(SerdReader* reader, ReadContext ctx, Ref* dest);
+
+static SerdStatus
+read_term(SerdReader* const reader,
+          const char* const term,
+          const unsigned    len,
+          Ref*              dest)
+{
+	*dest = push_node(reader, SERD_LITERAL, "", 0);
+
+	SerdStatus st;
+	for (unsigned i = 0; i < len; ++i) {
+		const char c = eat_byte(reader);
+		if (!c || c != term[i]) {
+			return SERD_ERR_BAD_SYNTAX;
+		} else if ((st = push_byte(reader, *dest, c))) {
+			return st;
+		}
+	}
+
+	return SERD_SUCCESS;
+}
+
+static SerdStatus
+read_hex(SerdReader* const reader, const Ref dest)
+{
+	SerdStatus st;
+	if (!(st = push_byte(reader, dest, eat_byte(reader)))) {
+		for (unsigned i = 0; i < 4; ++i) {
+			if (!is_xdigit(peek_byte(reader))) {
+				return SERD_ERR_BAD_SYNTAX;
+			}
+			push_byte(reader, dest, eat_byte(reader));
+		}
+	}
+	return st;
+}
+
+static SerdStatus
+read_escape(SerdReader* const reader, const Ref dest)
+{
+	switch (peek_byte(reader)) {
+	case '\"':
+	case '/':
+	case '\\':
+	case 'b':
+	case 'f':
+	case 'n':
+	case 'r':
+	case 't': return push_byte(reader, dest, eat_byte(reader));
+	case 'u': return read_hex(reader, dest);
+	default: return SERD_ERR_BAD_SYNTAX;
+	}
+}
+
+static SerdStatus
+pop_err(SerdReader* const reader, const SerdStatus st, const Ref ref)
+{
+	pop_node(reader, ref);
+	return st;
+}
+
+static SerdStatus
+read_string(SerdReader* const reader, Ref* dest)
+{
+	*dest = push_node(reader, SERD_LITERAL, "", 0);
+	if (!eat_byte_check(reader, '\"')) {
+		return pop_err(reader, SERD_ERR_BAD_SYNTAX, *dest);
+	}
+
+	SerdStatus st;
+	for (char c; (c = eat_byte(reader));) {
+		switch (c) {
+		case '\"': return SERD_SUCCESS;
+		case '\\':
+			if ((st = push_byte(reader, *dest, c)) ||
+			    (st = read_escape(reader, *dest))) {
+				return pop_err(reader, SERD_ERR_BAD_SYNTAX, *dest);
+			}
+			break;
+		default:
+			if (c >= 0 && c <= 0x1F) {
+				return pop_err(reader, SERD_ERR_BAD_SYNTAX, *dest);
+			} else if ((st = push_byte(reader, *dest, c))) {
+				return pop_err(reader, st, *dest);
+			}
+		}
+	}
+	return pop_err(reader, SERD_ERR_BAD_SYNTAX, *dest);
+}
+
+static SerdStatus
+expand_uri(SerdReader* const     reader,
+           const SerdNode* const node,
+           SerdChunk* const      uri_prefix,
+           SerdChunk* const      uri_suffix)
+{
+	if (serd_stack_is_empty(&reader->env_stack)) {
+		fprintf(stderr, "=> FAILURE\n");
+		return SERD_FAILURE;
+	}
+
+	SerdEnv* env = *(SerdEnv**)(reader->env_stack.buf + reader->env_stack.size -
+	                            sizeof(SerdEnv*));
+
+	return serd_env_expand(env, node, uri_prefix, uri_suffix);
+}
+
+static SerdStatus
+expand_term(SerdReader* const reader,
+            SerdNode* const   node,
+            Ref*              kref,
+            const SerdNode**  datatype)
+{
+	if (serd_stack_is_empty(&reader->env_stack)) {
+		return SERD_FAILURE;
+	}
+
+	SerdEnv* env = *(SerdEnv**)(reader->env_stack.buf + reader->env_stack.size -
+	                            sizeof(SerdEnv*));
+
+	SerdChunk  prefix = { 0, 0 };
+	SerdChunk  suffix = { 0, 0 };
+	SerdStatus st = serd_env_expand_term(env, node, &prefix, &suffix, datatype);
+
+	*kref = push_node(reader,
+	                  *datatype ? SERD_LITERAL : SERD_URI,
+	                  (const char*)prefix.buf,
+	                  prefix.len);
+	push_bytes(reader, *kref, suffix.buf, suffix.len);
+
+	return st;
+}
+
+static SerdStatus
+read_uri(SerdReader* const reader, Ref* dest)
+{
+	const SerdStatus st = read_string(reader, dest);
+	if (!st) {
+		SerdChunk prefix = { NULL, 0 };
+		SerdChunk suffix = { NULL, 0 };
+		SerdNode* node   = deref(reader, *dest);
+
+		fprintf(stderr, "EXPAND URI %s\n", node->buf);
+		node->type = SERD_CURIE;
+		if (!expand_uri(reader, node, &prefix, &suffix)) {
+			fprintf(stderr, " => EXPAND 1\n");
+			return SERD_SUCCESS;
+		}
+
+		node->type = SERD_URI;
+		if (!expand_uri(reader, node, &prefix, &suffix)) {
+			fprintf(stderr, " => EXPAND 2\n");
+			return SERD_SUCCESS;
+		}
+
+		fprintf(stderr, "=> NO EXPAND\n");
+	}
+	return st;
+}
+
+static SerdStatus
+read_digit(SerdReader* const reader, const Ref dest)
+{
+	return (is_digit(peek_byte(reader))
+	                ? push_byte(reader, dest, eat_byte(reader))
+	                : SERD_ERR_BAD_SYNTAX);
+}
+
+static SerdStatus
+read_digits(SerdReader* const reader, const Ref dest)
+{
+	SerdStatus st = read_digit(reader, dest);
+	while (!st) {
+		if ((st = read_digit(reader, dest)) == SERD_ERR_BAD_SYNTAX) {
+			return SERD_SUCCESS;
+		}
+	}
+	return st;
+}
+
+static SerdStatus
+read_sign(SerdReader* const reader, const Ref dest)
+{
+	switch (peek_byte(reader)) {
+	case '\0': return SERD_ERR_BAD_SYNTAX;
+	case '+':
+	case '-': return push_byte(reader, dest, eat_byte(reader));
+	}
+	return SERD_SUCCESS;
+}
+
+// Slightly more lax than the JSON standard, tolerates leading 0 and +
+static SerdStatus
+read_number(SerdReader* const reader, Ref* dest, Ref* datatype)
+{
+#define XSD_DOUBLE NS_XSD "double"
+#define XSD_INTEGER NS_XSD "integer"
+
+	*dest = push_node(reader, SERD_LITERAL, "", 0);
+
+	SerdStatus st;
+	bool       has_decimal = false;
+	if ((st = read_sign(reader, *dest))) {
+		return st;
+	}
+
+	if (peek_byte(reader) == '0') {
+		if ((st = push_byte(reader, *dest, eat_byte(reader)))) {
+			return st;
+		} else if (peek_byte(reader) != '.' && peek_byte(reader) != 'e') {
+			return SERD_SUCCESS;
+		}
+	} else if ((st = read_digits(reader, *dest))) {
+		return st;
+	}
+
+	if (peek_byte(reader) == '.') {
+		has_decimal = true;
+		if ((st = push_byte(reader, *dest, eat_byte(reader))) ||
+		    (st = read_digits(reader, *dest))) {
+			return st;
+		}
+	} else {
+		*datatype = push_node(
+		        reader, SERD_URI, XSD_INTEGER, sizeof(XSD_INTEGER) - 1);
+	}
+
+	if (peek_byte(reader) == 'E' || peek_byte(reader) == 'e') {
+		if ((st = push_byte(reader, *dest, eat_byte(reader))) ||
+		    (st = read_sign(reader, *dest)) ||
+		    (st = read_digits(reader, *dest))) {
+			return st;
+		}
+	}
+
+	*datatype = has_decimal ? push_node(reader,
+	                                    SERD_URI,
+	                                    XSD_DOUBLE,
+	                                    sizeof(XSD_DOUBLE) - 1)
+	                        : push_node(reader,
+	                                    SERD_URI,
+	                                    XSD_INTEGER,
+	                                    sizeof(XSD_INTEGER) - 1);
+
+	return SERD_SUCCESS;
+}
+
+static void
+skip_ws(SerdReader* const reader)
+{
+	for (char c; (c = peek_byte(reader));) {
+		switch (c) {
+		case '\t':
+		case '\r':
+		case '\n':
+		case ' ': eat_byte(reader); break;
+		default: return;
+		}
+	}
+}
+
+static SerdStatus
+read_sep(SerdReader* const reader, const char sep)
+{
+	skip_ws(reader);
+	if (eat_byte_check(reader, sep) == sep) {
+		skip_ws(reader);
+		return SERD_SUCCESS;
+	}
+	return SERD_ERR_BAD_SYNTAX;
+}
+
+static SerdStatus
+maybe_read_sep(SerdReader* const reader, const char sep)
+{
+	skip_ws(reader);
+	if (peek_byte(reader) == sep) {
+		eat_byte(reader);
+		skip_ws(reader);
+		return SERD_SUCCESS;
+	}
+	return SERD_FAILURE;
+}
+
+static SerdStatus
+read_value(SerdReader* const reader,
+           ReadContext       ctx,
+           Ref*              dest,
+           Ref*              datatype,
+           Ref*              lang)
+{
+#define XSD_DECIMAL NS_XSD "decimal"
+#define XSD_BOOLEAN NS_XSD "boolean"
+	skip_ws(reader);
+	switch (peek_byte(reader)) {
+	case '\0': return SERD_ERR_BAD_SYNTAX;
+	case '\"': return read_string(reader, dest);
+	case '[': return read_array(reader, ctx, dest);
+	case 'f':
+		*datatype = push_node(
+		        reader, SERD_URI, XSD_BOOLEAN, sizeof(XSD_BOOLEAN) - 1);
+		return read_term(reader, "false", 5, dest);
+	case 'n': return read_term(reader, "null", 4, dest);
+	case 't':
+		*datatype = push_node(
+		        reader, SERD_URI, XSD_BOOLEAN, sizeof(XSD_BOOLEAN) - 1);
+		return read_term(reader, "true", 4, dest);
+	case '{': return read_object(reader, ctx, dest, datatype, lang);
+
+	case '-':
+	case '0':
+	case '1':
+	case '2':
+	case '3':
+	case '4':
+	case '5':
+	case '6':
+	case '7':
+	case '8':
+	case '9': return read_number(reader, dest, datatype);
+
+	default: return SERD_ERR_BAD_SYNTAX;
+	}
+}
+
+static SerdStatus
+read_array(SerdReader* const reader, ReadContext ctx, Ref* dest)
+{
+	SerdStatus st;
+	if ((st = read_sep(reader, '['))) {
+		return st;
+	} else if (peek_byte(reader) == ']') {
+		read_sep(reader, ']');
+		return SERD_SUCCESS;
+	}
+
+	Ref vref = 0;
+	while (!st) {
+		if ((st = read_value(reader, ctx, &vref, &ctx.datatype, &ctx.lang))) {
+			return st;
+		}
+		emit_statement(reader, ctx, vref, ctx.datatype, ctx.lang);
+		skip_ws(reader);
+		if (peek_byte(reader) == ',') {
+			read_sep(reader, ',');
+		} else {
+			break;
+		}
+	}
+
+	return st || read_sep(reader, ']');
+}
+
+static SerdStatus
+read_list(SerdReader* const reader, ReadContext ctx, Ref* dest)
+{
+	SerdStatus st;
+	if ((st = read_sep(reader, '['))) {
+		return st;
+	} else if (peek_byte(reader) == ']') {
+		*dest = reader->rdf_nil;
+		read_sep(reader, ']');
+		return SERD_SUCCESS;
+	}
+
+	// subject predicate _:head
+	*dest = blank_id(reader);
+	emit_statement(reader, ctx, *dest, 0, 0);
+
+	/* The order of node allocation here is necessarily not in stack order,
+	   so we create two nodes and recycle them throughout. */
+	Ref n1   = push_node_padded(reader, genid_size(reader), SERD_BLANK, "", 0);
+	Ref n2   = 0;
+	Ref node = n1;
+	Ref rest = 0;
+
+	ctx.subject = *dest;
+	bool end    = peek_byte(reader) == ']';
+	while (!end) {
+		// _:node rdf:first object
+		ctx.predicate = reader->rdf_first;
+		Ref vref      = 0;
+		if ((st = read_value(reader, ctx, &vref, &ctx.datatype, &ctx.lang))) {
+			return st;
+		}
+		emit_statement(reader, ctx, vref, ctx.datatype, ctx.lang);
+
+		skip_ws(reader);
+		if (!(end = peek_byte(reader) != ',')) {
+			read_sep(reader, ',');
+			/* Give rest a new ID.  Done as late as possible to ensure it is
+			   used and > IDs generated by read_object above. */
+			if (!rest) {
+				rest = n2 = blank_id(reader);  // First pass, push
+			} else {
+				set_blank_id(reader, rest, genid_size(reader));
+			}
+		}
+
+		// _:node rdf:rest _:rest
+		*ctx.flags |= SERD_LIST_CONT;
+		ctx.predicate = reader->rdf_rest;
+		emit_statement(reader, ctx, (end ? reader->rdf_nil : rest), 0, 0);
+
+		ctx.subject = rest;         // _:node = _:rest
+		rest        = node;         // _:rest = (old)_:node
+		node        = ctx.subject;  // invariant
+	}
+
+	return st || read_sep(reader, ']');
+}
+
+static SerdStatus
+set_term(SerdReader* const     reader,
+         SerdEnv* const        env,
+         const SerdNode* const key,
+         const SerdNode* const value,
+         const SerdNode* const type)
+{
+	fprintf(stderr,
+	        "SET TERM %s %s %s\n",
+	        key->buf,
+	        value->buf,
+	        type ? (const char*)type->buf : "(null)");
+	SerdStatus st = serd_env_set_term(env, key, value, type);
+	if (!st && reader->prefix_sink) {
+		st = reader->prefix_sink(reader->handle, key, value);
+	}
+
+	return st;
+}
+
+static SerdStatus
+read_context_value(SerdReader* const     reader,
+                   SerdEnv* const        env,
+                   const SerdNode* const key)
+{
+	SerdStatus st = SERD_SUCCESS;
+	if (peek_byte(reader) == '{') {
+		st = read_sep(reader, '{');
+
+		Ref idref   = 0;
+		Ref typeref = 0;
+		while (!st) {
+			Ref kref = 0;
+			if ((st = read_string(reader, &kref)) ||
+			    (st = read_sep(reader, ':'))) {
+				return pop_err(reader, st, kref);
+			}
+
+			Ref vref = 0;
+			if ((st = read_uri(reader, &vref))) {
+				return pop_err(reader, st, vref);
+			}
+
+			SerdNode* ckey   = deref(reader, kref);
+			SerdNode* cvalue = deref(reader, vref);
+
+			fprintf(stderr, "CTX KEY: %s\n", ckey->buf);
+			fprintf(stderr, "CTX VAL: %s\n", cvalue->buf);
+
+			if (!strcmp((const char*)ckey->buf, "@id")) {
+				idref = vref;
+			} else if (!strcmp((const char*)ckey->buf, "@type")) {
+				if (!strcmp((const char*)cvalue->buf, "@id")) {
+					typeref = push_node(reader,
+					                    SERD_URI,
+					                    NS_RDFS "Resource",
+					                    strlen(NS_RDFS "Resource"));
+				} else {
+					typeref = vref;
+				}
+			}
+
+			if (maybe_read_sep(reader, ',')) {
+				break;
+			}
+		}
+
+		if ((st = read_sep(reader, '}'))) {
+			return st;
+		}
+
+		set_term(
+		        reader, env, key, deref(reader, idref), deref(reader, typeref));
+
+	} else {
+		fprintf(stderr, "SIMPLE\n");
+		Ref vref = 0;
+		if (!(st = read_uri(reader, &vref))) {
+			SerdNode* value = deref(reader, vref);
+
+			value->type = SERD_URI;
+			set_term(reader, env, key, value, NULL);
+		}
+	}
+
+	return st;
+}
+
+static SerdStatus
+read_context(SerdReader* const reader, ReadContext* ctx)
+{
+	SerdStatus st;
+	skip_ws(reader);
+	if (peek_byte(reader) != '{') {
+		Ref cref = 0;
+		read_uri(reader, &cref);
+		pop_node(reader, cref);
+		return SERD_SUCCESS;  // TODO: Context references?
+	}
+
+	if ((st = read_sep(reader, '{'))) {
+		return st;
+	}
+
+	SerdEnv*  env = serd_env_new(NULL);
+	SerdEnv** frame =
+	        (SerdEnv**)serd_stack_push(&reader->env_stack, sizeof(SerdEnv*));
+	*frame = env;
+
+	while (true) {
+		Ref kref = 0;
+		if ((st = read_string(reader, &kref)) || (st = read_sep(reader, ':'))) {
+			return pop_err(reader, st, kref);
+		}
+
+		SerdNode* key = deref(reader, kref);
+		if ((st = read_context_value(reader, env, key))) {
+			return pop_err(reader, st, kref);
+		}
+
+		if (maybe_read_sep(reader, ',')) {
+			break;
+		}
+	}
+
+	if ((st = read_sep(reader, '}'))) {
+		return st;
+	}
+
+	return SERD_SUCCESS;
+}
+
+static SerdStatus
+start_object(SerdReader* const reader, ReadContext ctx, const Ref ref)
+{
+	if (deref(reader, ref)->type == SERD_BLANK) {
+		set_blank_id(reader, ref, genid_size(reader));
+	}
+	if (ctx.subject && ctx.predicate) {
+		emit_statement(reader, ctx, ref, 0, 0);
+	}
+	return SERD_SUCCESS;
+}
+
+static SerdStatus
+read_object(SerdReader* const reader,
+            ReadContext       ctx,
+            Ref*              dest,
+            Ref*              datatype,
+            Ref*              lang)
+{
+	SerdStatus st;
+	if ((st = read_sep(reader, '{'))) {
+		return st;
+	}
+
+	Ref  id   = push_node_padded(reader, genid_size(reader), SERD_BLANK, "", 0);
+	Ref  kref = 0;  // Key
+	Ref  vref = 0;  // Value
+	bool is_literal = false;
+
+	while (true) {
+		if ((st = read_string(reader, &kref)) || (st = read_sep(reader, ':'))) {
+			return pop_err(reader, st, kref);
+		}
+
+		SerdNode* key = deref(reader, kref);
+		if (!strcmp((const char*)key->buf, "@list")) {
+			read_list(reader, ctx, dest);
+		} else if (!strcmp((const char*)key->buf, "@value")) {
+			is_literal = true;
+			pop_node(reader, kref);
+			if ((st = read_string(reader, dest))) {
+				return pop_err(reader, st, kref);
+			}
+		} else if (is_literal) {
+			if (!strcmp((const char*)key->buf, "@type")) {
+				if ((st = read_uri(reader, datatype))) {
+					return pop_err(reader, st, kref);
+				}
+			} else if (!strcmp((const char*)key->buf, "@language")) {
+				if ((st = read_string(reader, lang))) {
+					return pop_err(reader, st, kref);
+				}
+			} else {
+				r_err(reader,
+				      SERD_ERR_BAD_SYNTAX,
+				      "invalid literal property\n");
+				return pop_err(reader, SERD_ERR_BAD_SYNTAX, kref);
+			}
+		} else if (!strcmp((const char*)key->buf, "@id")) {
+			pop_node(reader, kref);
+			pop_node(reader, id);
+			if ((st = read_uri(reader, &id))) {
+				return SERD_ERR_BAD_SYNTAX;
+			}
+		} else if (!strcmp((const char*)key->buf, "@context")) {
+			pop_node(reader, kref);
+			read_context(reader, &ctx);
+		} else {
+			if (ctx.subject != id) {
+				start_object(reader, ctx, id);
+				ctx.subject = id;
+			}
+
+			SerdType vtype = SERD_LITERAL;
+			if (!strcmp((const char*)key->buf, "@type")) {
+				pop_node(reader, kref);
+				kref  = push_node(reader, SERD_URI, NS_RDF "type", 47);
+				vtype = SERD_URI;
+			} else {
+				const SerdNode* type          = NULL;
+				Ref             expanded_kref = 0;
+				expand_term(reader, key, &expanded_kref, &type);
+				if (expanded_kref) {
+					key       = deref(reader, expanded_kref);
+					key->type = SERD_URI;
+					fprintf(stderr, "KEY: %s\n", key->buf);
+					kref = expanded_kref;
+				}
+				/* if (!type) { */
+				/* 	vtype = SERD_URI; */
+				/* } */
+
+				if (type) {
+					fprintf(stderr, "DATATYPE: %s\n", type->buf);
+					if (!strcmp((const char*)type->buf, NS_RDFS "Resource")) {
+						vtype = SERD_URI;
+					} else {
+						ctx.datatype = push_node(reader,
+						                         type->type,
+						                         (const char*)type->buf,
+						                         type->n_bytes);
+					}
+				} else {
+					fprintf(stderr, "NO DATATYPE\n");
+					/* vtype = SERD_URI; */
+				}
+
+				key->type = SERD_URI;
+				/* SerdChunk prefix = { NULL, 0 }; */
+				/* SerdChunk suffix = { NULL, 0 }; */
+				/* if (!expand_uri(reader, key, &prefix, &suffix)) { */
+				/* 	key->type = SERD_CURIE; */
+				/* } else { */
+				/* 	key->type = SERD_URI; */
+				/* } */
+			}
+
+			ctx.predicate = kref;
+			if (vtype == SERD_URI) {
+				st = read_uri(reader, &vref);
+			} else {
+				st = read_value(reader, ctx, &vref, &ctx.datatype, &ctx.lang);
+			}
+
+			if (st) {
+				pop_node(reader, kref);
+				return pop_node(reader, ctx.subject);
+			}
+
+			emit_statement(reader, ctx, vref, ctx.datatype, ctx.lang);
+			pop_node(reader, vref);
+			pop_node(reader, kref);
+		}
+
+		if (maybe_read_sep(reader, ',')) {
+			break;
+		}
+	}
+	// pop_node(reader, ctx->subject); // FIXME
+
+	if ((st = read_sep(reader, '}'))) {
+		return st;
+	}
+
+	return SERD_SUCCESS;
+}
+
+bool
+read_js_statement(SerdReader* reader)
+{
+	return false;
+}
+
+bool
+read_js_doc(SerdReader* reader)
+{
+	SerdStatementFlags flags = 0;
+	ReadContext        ctx   = { 0, 0, 0, 0, 0, 0, &flags };
+
+	reader->env_stack = serd_stack_new(128);
+	Ref obj           = 0;
+	Ref datatype      = 0;
+	Ref lang          = 0;
+	if (read_object(reader, ctx, &obj, &datatype, &lang)) {
+		return false;
+	}
+	serd_stack_free(&reader->env_stack);
+
+	return true;
+}
diff --git a/src/reader.c b/src/reader.c
index 1a7f58d4..13831b13 100644
--- a/src/reader.c
+++ b/src/reader.c
@@ -152,7 +152,8 @@ static bool
 read_statement(SerdReader* reader)
 {
 	switch (reader->syntax) {
-	default: return read_n3_statement(reader);
+	case SERD_JSONLD: return read_js_doc(reader);
+	default:          return read_n3_statement(reader);
 	}
 }
 
@@ -160,6 +161,7 @@ static bool
 read_doc(SerdReader* reader)
 {
 	switch (reader->syntax) {
+	case SERD_JSONLD: return read_js_doc(reader);
 	case SERD_NQUADS: return read_nquadsDoc(reader);
 	default:          return read_turtleTrigDoc(reader);
 	}
@@ -184,7 +186,7 @@ serd_reader_new(SerdSyntax        syntax,
 	me->default_graph    = SERD_NODE_NULL;
 	me->stack            = serd_stack_new(SERD_PAGE_SIZE);
 	me->syntax           = syntax;
-	me->next_id          = 1;
+	me->next_id          = syntax == SERD_JSONLD ? 0 : 1;
 	me->strict           = true;
 
 	me->rdf_first = push_node(me, SERD_URI, NS_RDF "first", 48);
diff --git a/src/serd_internal.h b/src/serd_internal.h
index 73c8113b..9281334a 100644
--- a/src/serd_internal.h
+++ b/src/serd_internal.h
@@ -33,8 +33,9 @@
 #   include <fcntl.h>
 #endif
 
-#define NS_XSD "http://www.w3.org/2001/XMLSchema#"
-#define NS_RDF "http://www.w3.org/1999/02/22-rdf-syntax-ns#"
+#define NS_XSD  "http://www.w3.org/2001/XMLSchema#"
+#define NS_RDF  "http://www.w3.org/1999/02/22-rdf-syntax-ns#"
+#define NS_RDFS "http://www.w3.org/2000/01/rdf-schema#"
 
 #define SERD_PAGE_SIZE 4096
 
@@ -582,6 +583,7 @@ struct SerdReaderImpl {
 	SerdNode          default_graph;
 	SerdByteSource    source;
 	SerdStack         stack;
+	SerdStack         env_stack;
 	SerdSyntax        syntax;
 	unsigned          next_id;
 	SerdStatus        status;
@@ -621,6 +623,9 @@ bool read_n3_statement(SerdReader* reader);
 bool read_nquadsDoc(SerdReader* reader);
 bool read_turtleTrigDoc(SerdReader* reader);
 
+bool read_js_statement(SerdReader* reader);
+bool read_js_doc(SerdReader* reader);
+
 typedef enum {
 	FIELD_NONE,
 	FIELD_SUBJECT,
diff --git a/src/serdi.c b/src/serdi.c
index 03de46fd..3a308fae 100644
--- a/src/serdi.c
+++ b/src/serdi.c
@@ -40,6 +40,7 @@ static const Syntax syntaxes[] = {
 	{SERD_NTRIPLES, "ntriples", ".nt"},
 	{SERD_NQUADS,   "nquads",   ".nq"},
 	{SERD_TRIG,     "trig",     ".trig"},
+	{SERD_JSONLD,   "jsonld",   ".jsonld"},
 	{(SerdSyntax)0, NULL, NULL}
 };
 
@@ -255,7 +256,9 @@ main(int argc, char** argv)
 		}
 	}
 
-	if ((input_syntax == SERD_TURTLE || input_syntax == SERD_TRIG) ||
+	if ((input_syntax == SERD_TURTLE ||
+	     input_syntax == SERD_TRIG ||
+	     input_syntax == SERD_JSONLD) ||
 	    (output_style & SERD_STYLE_CURIED)) {
 		// Base URI may change and/or we're abbreviating URIs, so must resolve
 		output_style |= SERD_STYLE_RESOLVED;
diff --git a/src/writer.c b/src/writer.c
index 8dddf51c..370724af 100644
--- a/src/writer.c
+++ b/src/writer.c
@@ -565,6 +565,9 @@ write_curie(SerdWriter* const        writer,
 			sink(" ;", 2, writer);
 			write_newline(writer);
 		}
+		return true;
+	default:
+		return false;
 	}
 	return true;
 }