# projd-core
`projd-core` is the shared scanning model for Projd CLI and GUI. It detects
project markers, source languages, dependency manifests, tests, CI providers,
repository state, risks, project health, and per-language code line statistics.
The crate also provides project root discovery (`discover_roots`,
`DiscoverOptions`, `DiscoveredRoot`, `RootKind`) for directories that may
contain multiple independent projects with different VCS, build systems,
documentation sites, or datasets. Discovery terminates on detected root kinds
rather than directory depth.
Source control detection covers git, hg, svn, fossil, and bzr. Git, hg, and
svn populate branch / revision / last-commit / dirty fields by shelling out to
the corresponding CLI. Fossil and bzr currently report only marker presence;
the CLI-driven fields will be filled in a follow-up release. The `ProjectScan`
field is `vcs: VcsSummary` with `kind: VcsKind` (replaces the previous
`git: GitSummary` field as of 0.3.0).
`VcsSummary.activity` carries history-derived metrics: `days_since_last_commit`,
`commits_last_90d`, `contributors_count`, and `first_commit_date`. Only git
populates these fields in the current release; hg / svn / fossil / bzr leave
them as `None`. Contributor names and emails are not collected by default;
pass `ScanOptions { detailed_contributors: true }` to `scan_path_with` or
`scan_paths_recursive_with` to populate `VcsActivity.contributors`. The
`HealthSignalKind::Activity` signal reflects activity freshness against
thresholds of 90 days (active → pass) and 365 days (stale / dormant → warn).
The crate also exposes `scan_paths_recursive(path, opts) -> MultiProjectScan`,
which runs `discover_roots` on the path and then scans every detected root.
`MultiProjectScan` carries one `ProjectScan` per root plus an aggregated
`MultiProjectSummary` (`by_kind`, `by_grade`, `by_risk_level`,
`files_scanned`). Single-project `scan_path` runs a cheap multi-root check
and emits `RiskCode::MultipleVcsRootsFound` and `RiskCode::NestedVcsRoot` when
the scanned directory actually contains more than one root or a vendored
submodule.
This crate intentionally does not expose repository, homepage, or author metadata
in `Cargo.toml`, so published crates stay decoupled from local hosting details.