1 files changed, 127 insertions, 0 deletions
diff --git a/source/library/state/session-io.ts b/source/library/state/session-io.ts
new file mode 100644
index 0000000..a5e2ea9
--- /dev/null
+++ b/source/library/state/session-io.ts
@@ -0,0 +1,127 @@
+
+
+
+
+/*** UTILITY ------------------------------------------ ***/
+
+import type { Tab } from "./session.svelte.ts";
+
+const MAX_STRING_BYTES = 1024 * 1024;
+const MAX_TABS = 50;
+
+function isObject(value: unknown): value is Record<string, unknown> {
+  return typeof value === "object" && value !== null && !Array.isArray(value);
+}
+
+function stringTooLong(value: string): boolean {
+  return value.length > MAX_STRING_BYTES;
+}
+
+function validateTab(raw: unknown, index: number): TabExport | string {
+  if (!isObject(raw))
+    return `tabs[${index}]: not an object`;
+
+  if (typeof raw.headers !== "string")
+    return `tabs[${index}].headers: not a string`;
+
+  if (typeof raw.query !== "string")
+    return `tabs[${index}].query: not a string`;
+
+  if (typeof raw.title !== "string")
+    return `tabs[${index}].title: not a string`;
+
+  if (typeof raw.variables !== "string")
+    return `tabs[${index}].variables: not a string`;
+
+  if (raw.operationName !== null && typeof raw.operationName !== "string")
+    return `tabs[${index}].operationName: not a string or null`;
+
+  if (stringTooLong(raw.headers))
+    return `tabs[${index}].headers: exceeds 1 MB`;
+
+  if (stringTooLong(raw.query))
+    return `tabs[${index}].query: exceeds 1 MB`;
+
+  if (stringTooLong(raw.title))
+    return `tabs[${index}].title: exceeds 1 MB`;
+
+  if (stringTooLong(raw.variables))
+    return `tabs[${index}].variables: exceeds 1 MB`;
+
+  if (typeof raw.operationName === "string" && stringTooLong(raw.operationName))
+    return `tabs[${index}].operationName: exceeds 1 MB`;
+
+  return {
+    headers: raw.headers,
+    operationName: raw.operationName,
+    query: raw.query,
+    title: raw.title,
+    variables: raw.variables
+  };
+}
+
+/*** EXPORT ------------------------------------------- ***/
+
+export type TabExport = {
+  headers: string;
+  operationName: string | null;
+  query: string;
+  title: string;
+  variables: string;
+};
+
+export type SessionExport = {
+  exportedAt: string;
+  tabs: TabExport[];
+  version: 1;
+};
+
+export type ImportResult = {
+  added: number;
+  errors: string[];
+  skipped: number;
+};
+
+export function tabToExport(tab: Tab): TabExport {
+  return {
+    headers: tab.headers,
+    operationName: tab.operationName,
+    query: tab.query,
+    title: tab.title,
+    variables: tab.variables
+  };
+}
+
+export function validateSessionExport(data: unknown): SessionExport | { error: string } {
+  if (!isObject(data))
+    return { error: "not an object" };
+
+  if (data.version !== 1)
+    return { error: `unsupported version: ${String(data.version)}` };
+
+  if (typeof data.exportedAt !== "string")
+    return { error: "exportedAt: not a string" };
+
+  if (!Array.isArray(data.tabs))
+    return { error: "tabs: not an array" };
+
+  if (data.tabs.length > MAX_TABS)
+    return { error: `tabs: exceeds ${MAX_TABS}` };
+
+  const tabs: TabExport[] = [];
+
+  for (let i = 0; i < data.tabs.length; i++) {
+    const result = validateTab(data.tabs[i], i);
+
+    if (typeof result === "string")
+      return { error: result };
+
+    tabs.push(result);
+  }
+
+  return {
+    exportedAt: data.exportedAt,
+    tabs,
+    version: 1
+  };
+}