feat: integrate platform backend and application interfaces

server/tests/image-options.test.ts

@@ -0,0 +1,47 @@
+import test from "node:test";
+import assert from "node:assert/strict";
+import { imageModelFor, imageSizeFor, normalizeImageParams, OPENAI_IMAGE_RATIOS, OPENAI_IMAGE_RESOLUTIONS } from "../src/image-options.ts";
+
+test("OpenAI image ratio matrix produces aligned sizes for every resolution tier", () => {
+  for (const resolution of OPENAI_IMAGE_RESOLUTIONS) {
+    for (const ratio of OPENAI_IMAGE_RATIOS) {
+      const size = imageSizeFor(ratio, resolution);
+      if (ratio === "auto") {
+        assert.equal(size, "auto");
+        continue;
+      }
+      const match = /^(\d+)x(\d+)$/.exec(size);
+      assert.ok(match, `${resolution} ${ratio}`);
+      const width = Number(match[1]);
+      const height = Number(match[2]);
+      assert.equal(width % 16, 0);
+      assert.equal(height % 16, 0);
+      assert.ok(width >= 16 && height >= 16);
+      assert.ok(width * height <= 8_294_400);
+      assert.ok(Math.max(width, height) / Math.min(width, height) <= 3);
+    }
+  }
+});
+
+test("OpenAI image parameter defaults are explicit and transparent JPEG is coerced to PNG", () => {
+  const params = normalizeImageParams({ ratio: "16:9", resolution: "2K", background: "transparent", output_format: "jpeg" });
+  assert.equal(params.size, "2048x1152");
+  assert.equal(params.background, "transparent");
+  assert.equal(params.output_format, "png");
+  assert.equal(params.quality, "auto");
+  assert.equal(params.moderation, "auto");
+  assert.equal(params.ratio, undefined);
+  assert.equal(params.resolution, undefined);
+});
+
+test("OpenAI image model selection falls back from a missing tier mapping to the base model", () => {
+  assert.equal(imageModelFor("configured-image-model", "4K", { "1K": "mapped-1k" }), "configured-image-model");
+  assert.equal(imageModelFor(undefined, "2K", {}), "gpt-image-2");
+  assert.equal(imageModelFor("configured-image-model", "2K", { "2K": "mapped-2k" }), "mapped-2k");
+});
+
+test("invalid explicit image sizes are replaced by the selected ratio and resolution", () => {
+  assert.equal(normalizeImageParams({ size: "0x0", ratio: "1:1", resolution: "2K" }).size, "2048x2048");
+  assert.equal(normalizeImageParams({ size: "1000x1000", ratio: "1:1", resolution: "1K" }).size, "1024x1024");
+  assert.equal(normalizeImageParams({ size: "2048x1152", ratio: "16:9", resolution: "2K" }).size, "2048x1152");
+});