vpk-manifest-hygiene

name	vpk-manifest-hygiene
description	Enforce VPK manifest updates whenever VPK files are created, moved, renamed, enabled, disabled, or deleted. Use when modifying VPK-related Rust code, touching vpk_manager, manager.rs, mods.rs, profiles.rs, or any code that mutates the addons directory. Prevents state drift between on-disk VPKs and the .dmm.json manifest.
disable-model-invocation	true

VPK Manifest Hygiene

Every mutation to VPK files on disk must be followed by a corresponding update to the ProfileVpkManifest (.dmm.json). Skipping this causes state drift: the manifest no longer reflects reality, leading to ghost mods, missing mods, and broken enable/disable cycles.

The Manifest

• File: .dmm.json inside the profile's addons directory
• Struct: ProfileVpkManifest in apps/desktop/src-tauri/src/mod_manager/vpk_manifest.rs
• Tracks per-mod: enabled, current_vpks, disabled_vpks, original_vpk_names, order

The Rule

If you touch VPKs on disk, you must update and save the manifest in the same operation.

Concretely, any code path that does one of the following must call the corresponding manifest method and then manifest.save():

Disk operation	Manifest call
Install / enable VPKs	manifest.mark_enabled(mod_id, current_vpks, original_vpk_names, order)
Disable VPKs (prefix-rename)	manifest.mark_disabled(mod_id, disabled_vpks, original_vpk_names)
Uninstall / delete VPKs	manifest.remove_mod(mod_id)
Reorder VPKs	Update order via mark_enabled for affected mods
Replace / swap VPK files	mark_enabled or mark_disabled depending on final state

Existing Patterns to Follow

Look at the current call sites for reference:

• manager.rs — enable_mod, disable_mod, uninstall_mod, reorder_mods, replace_vpk_files
• mods.rs — persist_analyzed_mod, swap_mod_options, switch_download_variant
• profiles.rs — import_profile

Every one of these loads the manifest, mutates it, and saves it atomically (write-to-tmp then rename). Follow the same pattern.

Checklist for Code Review

When reviewing or writing code that touches VPK files:

• Manifest is loaded before disk mutations begin
• Every disk mutation has a matching manifest update
• manifest.save() is called after all mutations complete
• Error paths do not leave the manifest out of sync (save before early returns if partial work was done)
• No new VPK disk operations were added without manifest calls