rpg initial commit

src/main/java/org/zaine/app/controller/RpgSaveController.java

@@ -0,0 +1,45 @@
+package org.zaine.app.controller;
+
+import org.springframework.http.ResponseEntity;
+import org.springframework.web.bind.annotation.DeleteMapping;
+import org.springframework.web.bind.annotation.GetMapping;
+import org.springframework.web.bind.annotation.PathVariable;
+import org.springframework.web.bind.annotation.PutMapping;
+import org.springframework.web.bind.annotation.RequestBody;
+import org.springframework.web.bind.annotation.RequestMapping;
+import org.springframework.web.bind.annotation.RestController;
+import org.zaine.app.dto.RpgSaveDTO;
+import org.zaine.app.service.RpgSaveService;
+
+import io.swagger.v3.oas.annotations.tags.Tag;
+
+@RestController
+@RequestMapping("/api/play/rpg")
+@Tag(name = "RPG Saves", description = "Persistent save slots for browser RPGs")
+public class RpgSaveController {
+    private final RpgSaveService rpgSaveService;
+
+    public RpgSaveController(RpgSaveService rpgSaveService) {
+        this.rpgSaveService = rpgSaveService;
+    }
+
+    @GetMapping("/save/{slot}")
+    public ResponseEntity<RpgSaveDTO> load(@PathVariable String slot) {
+        RpgSaveDTO save = rpgSaveService.load(slot);
+        if (save == null) {
+            return ResponseEntity.notFound().build();
+        }
+        return ResponseEntity.ok(save);
+    }
+
+    @PutMapping("/save/{slot}")
+    public ResponseEntity<RpgSaveDTO> save(@PathVariable String slot, @RequestBody RpgSaveDTO dto) {
+        return ResponseEntity.ok(rpgSaveService.save(slot, dto.getPayload()));
+    }
+
+    @DeleteMapping("/save/{slot}")
+    public ResponseEntity<Void> delete(@PathVariable String slot) {
+        rpgSaveService.delete(slot);
+        return ResponseEntity.noContent().build();
+    }
+}

src/main/java/org/zaine/app/dto/RpgSaveDTO.java

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+package org.zaine.app.dto;
+
+import com.fasterxml.jackson.databind.JsonNode;
+
+public class RpgSaveDTO {
+    private String slot;
+    private JsonNode payload;
+
+    public String getSlot() {
+        return slot;
+    }
+
+    public void setSlot(String slot) {
+        this.slot = slot;
+    }
+
+    public JsonNode getPayload() {
+        return payload;
+    }
+
+    public void setPayload(JsonNode payload) {
+        this.payload = payload;
+    }
+}

src/main/java/org/zaine/app/service/RpgSaveService.java

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+package org.zaine.app.service;
+
+import java.io.IOException;
+import java.nio.file.Files;
+import java.nio.file.Path;
+
+import org.springframework.beans.factory.annotation.Value;
+import org.springframework.stereotype.Service;
+import org.zaine.app.dto.RpgSaveDTO;
+
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.node.ObjectNode;
+
+@Service
+public class RpgSaveService {
+    private final ObjectMapper objectMapper;
+    private final Path saveDirectory;
+
+    public RpgSaveService(
+            ObjectMapper objectMapper,
+            @Value("${play.rpg.save-dir:${user.home}/.org-web-rpg-saves}") String saveDirectory) {
+        this.objectMapper = objectMapper;
+        this.saveDirectory = Path.of(saveDirectory);
+    }
+
+    public RpgSaveDTO load(String slot) {
+        Path file = savePath(slot);
+        if (!Files.exists(file)) {
+            return null;
+        }
+        try {
+            return objectMapper.readValue(file.toFile(), RpgSaveDTO.class);
+        } catch (IOException e) {
+            throw new RuntimeException("Failed to load RPG save", e);
+        }
+    }
+
+    public RpgSaveDTO save(String slot, JsonNode payload) {
+        try {
+            Files.createDirectories(saveDirectory);
+            RpgSaveDTO dto = new RpgSaveDTO();
+            dto.setSlot(slot);
+            dto.setPayload(payload);
+
+            ObjectNode wrapped = objectMapper.createObjectNode();
+            wrapped.put("slot", slot);
+            wrapped.set("payload", payload);
+            objectMapper.writerWithDefaultPrettyPrinter().writeValue(savePath(slot).toFile(), wrapped);
+            return dto;
+        } catch (IOException e) {
+            throw new RuntimeException("Failed to save RPG progress", e);
+        }
+    }
+
+    public void delete(String slot) {
+        try {
+            Files.deleteIfExists(savePath(slot));
+        } catch (IOException e) {
+            throw new RuntimeException("Failed to delete RPG save", e);
+        }
+    }
+
+    private Path savePath(String slot) {
+        if (slot == null || !slot.matches("[A-Za-z0-9_-]{1,64}")) {
+            throw new IllegalArgumentException("Invalid RPG save slot");
+        }
+        return saveDirectory.resolve(slot + ".json").normalize();
+    }
+}