#Diffs

// Create two versions from the same base
const versionA = await createVersion({
  lix,
  name: "version-a",
  from: activeVersion,
});
const versionB = await createVersion({
  lix,
  name: "version-b",
  from: activeVersion,
});

// Modify the product in version A (change price)
await lix.db
  .updateTable("state_by_version")
  .set({ snapshot_content: { id: "product-1", name: "Widget", price: 12 } })
  .where("version_id", "=", versionA.id)
  .where("entity_id", "=", "product-1")
  .execute();

// Compare versions: what changed from B to A?
const diff = await selectVersionDiff({
  lix,
  source: versionA,
  target: versionB,
})
  .where("status", "!=", "unchanged")
  .execute();

console.log("Changes between versions:");
for (const row of diff) {
  console.log(`  ${row.entity_id}: ${row.status}`);
}

// The power of SQL: compose custom diff queries with filters and joins
const productDiffs = await selectVersionDiff({
  lix,
  source: versionA,
  target: versionB,
})
  // Filter to specific schema
  .where("diff.schema_key", "=", "product")
  // Only show actual changes
  .where("diff.status", "!=", "unchanged")
  // Join to get before/after snapshot content
  .leftJoin("change as before", "before.id", "diff.before_change_id")
  .leftJoin("change as after", "after.id", "diff.after_change_id")
  .select([
    "diff.entity_id",
    "diff.status",
    "before.snapshot_content as before_content",
    "after.snapshot_content as after_content",
  ])
  .execute();

console.log("Product changes with content:");
for (const row of productDiffs) {
  const before = row.before_content as any;
  const after = row.after_content as any;

  if (before?.price !== after?.price) {
    console.log(
      `  ${row.entity_id}: price ${before?.price} → ${after?.price}`,
    );
  }
}