Use solady/libzip to store compressed html

src/HTMLRegistry.sol

@@ -2,7 +2,8 @@
 pragma solidity ^0.8.13;
 
 import {SSTORE2} from "solady/utils/SSTORE2.sol";
-
+import {LibBytes} from "solady/utils/LibBytes.sol";
+import {LibZip} from "solady/utils/LibZip.sol";
 interface IOwnable {
     function owner() external view returns (address);
 }
@@ -44,7 +45,11 @@ contract HTMLRegistry {
     function _html(address author, address target, uint256 version) internal view returns (bytes memory) {
         address ptr = sPtrs[author][target][version];
         if (ptr == address(0)) return new bytes(0);
-        return SSTORE2.read(ptr);
+        bytes memory data = SSTORE2.read(ptr);
+
+        if (bytes4(bytes32(data)) == bytes4(0xffffffff)) return LibZip.flzDecompress(LibBytes.slice(data, 4));
+
+        return data;
     }
 
     function setHtml(address target, bytes calldata htmlData) external onlyAuthorized(target) {

test/HTMLRegistry.t.sol

@@ -2,7 +2,9 @@
 pragma solidity ^0.8.13;
 
 import {Test} from "forge-std/Test.sol";
+import {console2} from "forge-std/console2.sol";
 import {HTMLRegistry} from "../src/HTMLRegistry.sol";
+import {LibZip} from "solady/utils/LibZip.sol";
 
 contract HTMLRegistryTest is Test {
     HTMLRegistry public registry;
@@ -101,6 +103,54 @@ contract HTMLRegistryTest is Test {
         assertEq(registry.html(alice, alice, 2), new bytes(0));
     }
 
+    function test_html_decompressesWhenPrefixed() public {
+        bytes memory compressed = bytes.concat(bytes4(0xffffffff), LibZip.flzCompress(_HTML));
+        vm.prank(alice);
+        registry.setHtml(alice, compressed);
+
+        assertEq(registry.html(alice, alice), _HTML);
+    }
+
+    function test_html_returnsRawWhenPrefixDoesNotMatch() public {
+        bytes memory payload = bytes.concat(bytes4(0xdeadbeef), bytes("raw bytes"));
+        vm.prank(alice);
+        registry.setHtml(alice, payload);
+
+        assertEq(registry.html(alice, alice), payload);
+    }
+
+    function test_html_returnsRawWhenDataTooShortForPrefix() public {
+        bytes memory payload = hex"010203";
+        vm.prank(alice);
+        registry.setHtml(alice, payload);
+
+        assertEq(registry.html(alice, alice), payload);
+    }
+
+    function test_storageMetrics_plainVsCompressed() public {
+        bytes memory compressedBody = LibZip.flzCompress(_HTML);
+        bytes memory compressedPayload = bytes.concat(bytes4(0xffffffff), compressedBody);
+
+        vm.startPrank(alice);
+        uint256 gasStartPlain = gasleft();
+        registry.setHtml(alice, _HTML);
+        uint256 gasUsedPlain = gasStartPlain - gasleft();
+
+        uint256 gasStartCompressed = gasleft();
+        registry.setHtml(alice, compressedPayload);
+        uint256 gasUsedCompressed = gasStartCompressed - gasleft();
+        vm.stopPrank();
+
+        assertEq(registry.html(alice, alice, 1), _HTML);
+        assertEq(registry.html(alice, alice, 2), _HTML);
+
+        console2.log("plain length", _HTML.length);
+        console2.log("compressed length", compressedBody.length);
+        console2.log("compressed+selector length", compressedPayload.length);
+        console2.log("plain write gas", gasUsedPlain);
+        console2.log("compressed write gas", gasUsedCompressed);
+    }
+
     function test_emitsHtmlSet() public {
         vm.startPrank(alice);
         vm.expectEmit(true, true, false, true);