deserialization and serialization is usable

encoding/json.jai

@@ -22,11 +22,102 @@ Json_Value :: struct {
    }
 }
 
-json_marshal :: (value: $T) -> string {
-   return "";
+json_serialize :: (value: $T) -> Json_Value {
+   json_serialize_with_info :: (info: *Type_Info, value: *void) -> Json_Value {
+      if value == null {
+         return .{ kind = .none };
+      }
+
+      if info.type == {
+         case .BOOL;
+            return .{ kind = .bool, b = value.(*bool).* };
+
+         case .INTEGER;
+            i_info := info.(*Type_Info_Integer);
+            if i_info.signed {
+               if i_info.runtime_size == {
+                  case 1; return .{ kind = .number, n = (value.( *s8).*).(float64) };
+                  case 2; return .{ kind = .number, n = (value.(*s16).*).(float64) };
+                  case 4; return .{ kind = .number, n = (value.(*s32).*).(float64) };
+                  case 8; return .{ kind = .number, n = (value.(*s64).*).(float64) };
+                  case; basic.assert(false, "unknown float size: %", info.runtime_size);
+               }
+            }
+            else {
+               if i_info.runtime_size == {
+                  case 1; return .{ kind = .number, n = (value.( *u8).*).(float64) };
+                  case 2; return .{ kind = .number, n = (value.(*u16).*).(float64) };
+                  case 4; return .{ kind = .number, n = (value.(*u32).*).(float64) };
+                  case 8; return .{ kind = .number, n = (value.(*u64).*).(float64) };
+                  case; basic.assert(false, "unknown float size: %", info.runtime_size);
+               }
+            }
+
+         case .FLOAT;
+            if info.runtime_size == {
+               case 4; return .{ kind = .number, n = (value.(*float32).*).(float64) };
+               case 8; return .{ kind = .number, n = (value.(*float64).*) };
+               case; basic.assert(false, "unknown float size: %", info.runtime_size);
+            }
+
+         case .STRING;
+            return .{ kind = .string, s = (value.(*string)).* };
+
+         case .STRUCT;
+            json_obj: Json_Value;
+            json_obj.kind = .object;
+
+            obj  := *json_obj.object;
+            vptr := value.(*u8);
+
+            s_info := info.(*Type_Info_Struct);
+            for s_info.members if it.offset_in_bytes >= 0 {
+               name := get_json_member_name(it);
+               basic.array_add(*obj.keys, name);
+
+               field_value := vptr + it.offset_in_bytes;
+               basic.array_add(*obj.values, json_serialize_with_info(it.type, field_value));
+            }
+
+            return json_obj;
+
+         case .ARRAY;
+            json_array: Json_Value;
+            json_array.kind = .array;
+
+            arr  := *json_array.array;
+            vptr := value.(*u8);
+
+            a_info  := info.(*Type_Info_Array);
+            el_info := a_info.element_type;
+
+            if a_info.array_type == {
+               case .FIXED;
+                  for 0..a_info.array_count - 1 {
+                     el_ptr := vptr + (it * el_info.runtime_size);
+                     basic.array_add(arr, json_serialize_with_info(el_info, el_ptr));
+                  }
+
+               case .VIEW; #through;
+               case .RESIZABLE;
+                  data := vptr.(*[]u8);
+                  for 0..data.count - 1 {
+                     el_ptr := data.data + (it * el_info.runtime_size);
+                     basic.array_add(arr, json_serialize_with_info(el_info, el_ptr));
+                  }
+            }
+
+            return json_array;
+      }
+
+      basic.assert(false, "unhandled type in marshal: %", info.type);
+      return .{};
+   }
+
+   return json_serialize_with_info(T.(*Type_Info), *value);
 }
 
-json_unmarshal :: (data: string) -> (Json_Value, bool) {
+json_deserialize :: (data: string) -> (Json_Value, bool) {
    p := Parser.{
       data      = data.([]u8),
       allocator = context.allocator,
@@ -36,9 +127,144 @@ json_unmarshal :: (data: string) -> (Json_Value, bool) {
    return parse_value(*p), p.error.count == 0;
 }
 
-json_unmarshal :: (data: string, $T: Type) -> (T, bool) {
-   zero: T;
-   return zero, false;
+json_deserialize :: ($T: Type, data: string) -> (T, bool) {
+   json_deserialize_with_info :: (info: *Type_Info, json: Json_Value, ptr: *void) -> bool {
+      if json.kind == {
+         case .none; return true;
+
+         case .bool;
+            basic.assert(info.type == .BOOL, "cannot deserialize % into %", json.b, info.type); // @errors
+            ptr.(*bool).* = json.b;
+
+         case .number;
+            if info.type == {
+               case .INTEGER;
+                  i_info := info.(*Type_Info_Integer);
+                  if i_info.signed {
+                     // @todo(judah): bounds check to make sure this is safe
+                     if i_info.runtime_size == {
+                        case 1; ptr.(*s8 ).* = json.n.(s8 );
+                        case 2; ptr.(*s16).* = json.n.(s16);
+                        case 4; ptr.(*s32).* = json.n.(s32);
+                        case 8; ptr.(*s64).* = json.n.(s64);
+                        case; basic.assert(false, "unhandled int size % in deserialize", i_info.runtime_size);
+                     }
+                  }
+                  else {
+                     if i_info.runtime_size == {
+                        case 1; ptr.(*u8 ).* = json.n.(u8 );
+                        case 2; ptr.(*u16).* = json.n.(u16);
+                        case 4; ptr.(*u32).* = json.n.(u32);
+                        case 8; ptr.(*u64).* = json.n.(u64);
+                        case; basic.assert(false, "unhandled uint size % in deserialize", i_info.runtime_size);
+                     }
+                  }
+
+               case .FLOAT;
+                  if info.runtime_size == {
+                     case 4; ptr.(*float32).* = json.n.(float32);
+                     case 8; ptr.(*float64).* = json.n.(float64);
+                     case; basic.assert(false, "unhandled float size % in deserialize", info.runtime_size);
+                  }
+            }
+
+            return true;
+
+         case .string;
+            basic.assert(info.type == .STRING, "cannot deserialize '%' into %", json.s, info.type); // @errors
+            sptr := ptr.(*string);
+            sptr.data  = basic.copy_string(json.s).data;
+            sptr.count = json.s.count;
+            return true;
+
+         case .object;
+            basic.assert(info.type == .STRUCT, "cannot deserialize json object into %", info.type); // @errors
+
+            vptr   := ptr.(*u8);
+            s_info := info.(*Type_Info_Struct);
+            for mem: s_info.members {
+               found := false;
+               name  := get_json_member_name(mem);
+
+               value: Json_Value;
+               for json.object.keys if it == name { // @todo(judah): handle custom names in notes
+                  found = true;
+                  value = json.object.values[it_index];
+                  break;
+               }
+
+               if !found continue;
+
+               field_ptr := vptr + mem.offset_in_bytes;
+               if !json_deserialize_with_info(mem.type, value, field_ptr) {
+                  return false;
+               }
+            }
+
+            return true;
+
+         case .array;
+            basic.assert(info.type == .ARRAY, "cannot deserialize json array into %", info.type); // @errors
+
+            vptr    := ptr.(*u8);
+            a_info  := info.(*Type_Info_Array);
+            el_info := a_info.element_type;
+
+            if a_info.array_type == {
+               case .FIXED;
+                  basic.assert(json.array.count <= a_info.array_count);
+
+                  for 0..a_info.array_count - 1 {
+                     el_ptr := vptr + (it * el_info.runtime_size);
+                     value  := json.array[it];
+                     if !json_deserialize_with_info(el_info, value, el_ptr) {
+                        return false;
+                     }
+                  }
+
+               case .VIEW; #through;
+               case .RESIZABLE;
+                  data := basic.alloc(json.array.count * el_info.runtime_size).(*u8);
+                  if json.array.count == 0 {
+                     return true;
+                  }
+
+                  // @todo(judah): verify the json array is homogenous
+                  for json.array {
+                     el_ptr := data + (it_index * el_info.runtime_size);
+                     if !json_deserialize_with_info(el_info, it, el_ptr) {
+                        return false;
+                     }
+                  }
+
+                  if a_info.array_type == .VIEW {
+                     out := ptr.(*[]u8);
+                     out.data  = data;
+                     out.count = json.array.count;
+                  }
+                  else {
+                     out := ptr.(*[..]u8);
+                     out.data      = data;
+                     out.count     = json.array.count;
+                     out.allocated = json.array.count;
+                  }
+
+                  return true;
+            }
+
+            return true;
+      }
+
+      basic.assert(false, "unhandled json value: %", json.kind);
+      return false;
+   }
+
+   json, ok := json_deserialize(data);
+   if !ok return zero_of(T), ok;
+
+   out: T;
+   ok = json_deserialize_with_info(T.(*Type_Info), json, *out);
+   return out, ok;
 }
 
 to_string :: (value: Json_Value, indent := 0) -> string {
@@ -101,6 +327,17 @@ to_string :: (value: Json_Value, indent := 0) -> string {
 
 #scope_file;
 
+get_json_member_name :: (member: Type_Info_Struct_Member) -> string {
+   name := member.name;
+   for member.notes if strings.contains(it, "json:") {
+      name = .{ data = it.data + 5, count = it.count - 5 };
+      name = strings.replace(name, "\\_", " ");
+      break;
+   }
+
+   return name;
+}
+
 Parser :: struct {
    allocator: Allocator;
    data:      []u8;
@@ -109,13 +346,100 @@ Parser :: struct {
    line:      uint;
 }
 
-parse_value :: (p: *Parser) -> Json_Value {
+Token :: struct {
+   kind: enum {
+      invalid;
+      eof;
+      true_;
+      false_;
+      null_;
+      number;
+      str;
+
+      colon    :: #char ":";
+      comma    :: #char ",";
+      l_brace  :: #char "{";
+      r_brace  :: #char "}";
+      l_square :: #char "[";
+      r_square :: #char "]";
+   };
+
+   str: string;
+}
+
+get_next_token :: (p: *Parser) -> Token {
    skip_whitespace(p);
 
    if at_end(p) {
-      return .{};
+      return .{ kind = .eof };
    }
 
+   c := p.data[p.offset];
+   if c == {
+      case #char ":"; #through;
+      case #char ","; #through;
+      case #char "{"; #through;
+      case #char "}"; #through;
+      case #char "["; #through;
+      case #char "]";
+         p.offset += 1;
+         return .{ kind = xx c };
+   }
+
+   // Comments
+   if c == #char "/" && p.offset + 1 < p.data.count.(uint) && p.data[p.offset+1] == #char "/" {
+      capture_while(p, c => c != #char "\n");
+      return get_next_token(p);
+   }
+
+   // Strings
+   // @todo(judah): handle escaped quotes
+   if c == #char "\"" {
+      p.offset += 1; // skip "
+      str := capture_while(p, s => s != #char "\"");
+      p.offset += 1; // skip "
+      return .{ kind = .str, str = str };
+   }
+
+   // Numbers
+   if (c >= #char "0" && c <= #char "9") || c == #char "." {
+      number := capture_while(p, n => (n >= #char "0" && n <= #char "9") || n == #char ".");
+      return .{ kind = .number, str = number };
+   }
+
+   // true, false, null
+   if (c >= #char "a" && c <= #char "z") {
+      keyword := capture_while(p, n => (n >= #char "a" && n <= #char "z"));
+      if keyword == {
+         case "true";
+            return .{ kind = .true_ };
+         case "false";
+            return .{ kind = .false_ };
+         case "null";
+            return .{ kind = .null_ };
+         case;
+            return .{ kind = .invalid, str = keyword };
+      }
+   }
+
+   return .{ kind = .eof };
+}
+
+peek_token :: (p: *Parser) -> Token {
+   copy := p.*; // @todo(judah): this is bad?
+   return get_next_token(*copy);
+}
+
+expect :: (p: *Parser, kinds: ..type_of(Token.kind)) -> (bool, Token) {
+   tok := get_next_token(p);
+   for kinds if it == tok.kind {
+      return true, tok;
+   }
+
+   return false, tok;
+}
+
+parse_value :: (p: *Parser) -> Json_Value {
    to_string :: (c: u8) -> string #expand {
       str: string;
       str.data  = *c;
@@ -123,28 +447,54 @@ parse_value :: (p: *Parser) -> Json_Value {
       return str;
    }
 
-   c := p.data[p.offset];
-   if c == {
-      case #char "{";
-         p.offset += 1; // skip {
+   ok, tok := expect(p, .l_brace, .l_square, .str, .number, .true_, .false_, .null_);
+   if !ok {
+      set_error(p, "expected value, found '%'", tok.str);
+      return .{};
+   }
 
+   if tok.kind == {
+      case .number;
+         number := tok.str;
+
+         // @todo(judah): parse_float works a bit weird
+         f, ok := strings.parse_float(*number);
+         if !ok {
+            set_error(p, "malformed number '%'", tok.str);
+            return .{};
+         }
+
+         return .{ kind = .number, n = f };
+
+      case .true_; #through;
+      case .false_;
+         return .{ kind = .bool, b = tok.kind == .true_ };
+
+      case .null_;
+         return .{ kind = .none };
+
+      case .str;
+         return .{ kind = .string, s = tok.str };
+
+      case .l_brace;
          object: Json_Value;
          object.kind = .object;
-         object.object.keys.allocator   = p.allocator;
-         object.object.values.allocator = p.allocator;
 
-         skip_whitespace(p);
+         obj := *object.object;
+         obj.keys.allocator   = p.allocator;
+         obj.values.allocator = p.allocator;
+
          while !at_end(p) {
-            c = p.data[p.offset];
-            if c == #char "}" break;
+            end := peek_token(p);
+            if end.kind == .r_brace break;
 
-            key := parse_value(p);
-            if p.error.count != 0 || key.kind != .string {
+            key_ok, key := expect(p, .str);
+            if !key_ok {
                set_error(p, "expected key for object");
                return .{};
             }
 
-            if !expect(p, #char ":") {
+            if !expect(p, .colon) {
                set_error(p, "missing ':' after key");
                return .{};
             }
@@ -154,109 +504,61 @@ parse_value :: (p: *Parser) -> Json_Value {
                return .{};
             }
 
-            if !expect(p, #char ",") {
-               set_error(p, "expected ',' after value in object");
+            basic.array_add(*obj.keys, key.str);
+            basic.array_add(*obj.values, value);
+
+            end = peek_token(p);
+            if end.kind == .r_brace break;
+
+            if !expect(p, .comma) {
+               set_error(p, "missing ',' after value");
                return .{};
             }
-
-            basic.array_add(*object.object.keys, key.s);
-            basic.array_add(*object.object.values, value);
          }
 
-         p.offset += 1; // skip }
+         if !expect(p, .r_brace) {
+            set_error(p, "missing '}' at end of object");
+            return .{};
+         }
+
          return object;
 
-      case #char "[";
-         p.offset += 1; // skip [
-
+      case .l_square;
          array: Json_Value;
          array.kind = .array;
          array.array.allocator = p.allocator;
 
-         skip_whitespace(p);
          while !at_end(p) {
-            c = p.data[p.offset];
-            if c == #char "]" break;
+            end := peek_token(p);
+            if end.kind == .r_square break;
 
-            v := parse_value(p);
+            value := parse_value(p);
             if p.error.count != 0 {
-               set_error(p, "expected value for array");
                return .{};
             }
 
-            if !expect(p, #char ",") {
-               set_error(p, "expected ',' after value in array");
+            basic.array_add(*array.array, value);
+
+            end = peek_token(p);
+            if end.kind == .r_square break;
+
+            if !expect(p, .comma) {
+               set_error(p, "missing ',' after value");
                return .{};
             }
-
-            basic.array_add(*array.array, v);
          }
 
-         p.offset += 1; // skip ]
-
-         return array;
-
-      case #char "\"";
-         p.offset += 1;
-
-         str := capture_while(p, s => s != #char "\"");
-         basic.assert(str.count != 0);
-
-         p.offset += 1;
-
-         return .{ kind = .string, s = str };
-
-      case;
-         // number
-         if (c >= #char "0" && c <= #char "9") || c == #char "." {
-            number := capture_while(p, n => (n >= #char "0" && n <= #char "9") || n == #char ".");
-            basic.assert(number.count != 0);
-
-            // @todo(judah): parse_float works a bit weird
-            f, ok := strings.parse_float(*number);
-            if !ok {
-               set_error(p, "malformed number '%'", number);
-               return .{};
-            }
-
-            return .{ kind = .number, n = f };
-         }
-
-         // true, false, null
-         if (c >= #char "a" && c <= #char "z") {
-            keyword := capture_while(p, k => k >= #char "a" && k <= #char "z");
-            basic.assert(keyword.count != 0);
-
-            if keyword == {
-               case "true";
-                  return .{ kind = .bool, b = true };
-               case "false";
-                  return .{ kind = .bool, b = false };
-               case "null";
-                  return .{ kind = .none };
-            }
-
-            set_error(p, "expected number, true, false, null but found '%'", keyword);
+         if !expect(p, .r_square) {
+            set_error(p, "missing ']' at end of array");
             return .{};
          }
 
-         set_error(p, "expected number, true, false, null but found '%'", to_string(c));
-         return .{};
+         return array;
    }
 
    return .{};
 }
 
-expect :: (p: *Parser, c: u8) -> bool {
-   if at_end(p) || p.data[p.offset] != c {
-      return false;
-   }
-
-   p.offset += 1;
-   skip_whitespace(p);
-   return true;
-}
-
 set_error :: (p: *Parser, message: string, args: ..Any) {
    p.error = basic.tprint("line %, %", p.line, basic.tprint(message, ..args));
 }