trusty-mpm 1.4.2

//! The skill half of session provisioning, extracted from [`super`] (#5224).
//!
//! Why: `session_launch/mod.rs` sat exactly at the 500-SLOC production cap, so
//! the #5224 retirement sweep could not be added to it without a split — and
//! the skill block is the natural seam. Everything the launch does about skills
//! is one sequence: warn about staleness, resolve the three tiers' stems, log
//! what each agent declared, deploy, then retire what no source ships any more.
//! Splitting it out keeps that sequence readable in one place instead of buried
//! among agent, MCP, hook, and instruction provisioning.
//!
//! What: [`deploy_session_skills`] runs that sequence and returns the
//! [`DeployStats`] the caller reports. Skill deployment is NON-FATAL to a
//! launch — a failure is logged, pushed onto `roster_errors`, and the session
//! starts without the skill set rather than not starting at all.
//!
//! Test: exercised end-to-end through `super::prepare_session` by
//! `session_launch::tests`; the retirement sweep itself is tested in
//! `crate::core::skill_retire`.

use std::collections::HashMap;
use std::path::Path;

use crate::core::agent_skill_codeploy::{co_deploy_skill_set, log_declared_skills};
use crate::core::manifest::HarnessPlan;
use crate::core::paths::FrameworkPaths;
use crate::core::skill_deployer::DeployStats;
use crate::core::skill_tiers::{
    deploy_all_skill_tiers, list_project_custom_stems, list_source_stems,
};

/// Deploy the session's skill set and retire what the binary no longer ships.
///
/// Why: see the module doc — one sequence, one place. The pieces are ordered so
/// each feeds the next: the stem sets resolved for the co-deploy `select`
/// predicate are the same ones the declared-skill logging reports against, so
/// neither needs a second directory scan.
/// What: warns when the workspace's deployed skills lag the bundled source,
/// resolves the project / user / bundled stem sets, logs every agent-declared
/// skill's resolution (DOC-42, §SPEC-AGENTSKILLS-05), deploys the three tiers
/// with precedence project-custom > user-custom > bundled (#2816), then sweeps
/// every deploy tier for skills no source ships any more (#5224). A deploy
/// failure is recorded in `roster_errors` and yields empty stats.
/// Test: `session_launch::tests`, plus `crate::core::skill_retire`'s own suite.
pub(super) fn deploy_session_skills(
    fw: &FrameworkPaths,
    plan: &HarnessPlan,
    project_dir: &Path,
    declared_skills: &HashMap<String, Vec<String>>,
    roster_errors: &mut Vec<String>,
) -> DeployStats {
    // #4583/#4604: a long-lived worktree that never re-provisioned keeps the old
    // skill text (e.g. an outdated attribution footer) until this very deploy
    // self-heals it. The warn makes that drift auditable. Non-fatal, read-only.
    let stale =
        crate::core::skill_staleness::stale_skills(&plan.skill_source, &fw.claude_skills_dir());
    if !stale.is_empty() {
        tracing::warn!(
            project_dir = %project_dir.display(),
            stale_skills = %stale.join(", "),
            "deployed skills were stale relative to bundled assets — refreshing now \
             (run `tm doctor` to audit; long-lived worktrees drift until re-provisioned)"
        );
    }

    // DOC-42 (issue #2889): fold every deployed agent's declared `skills:` into
    // the bundled-tier `select` predicate below, so a skill the harness manifest
    // would otherwise exclude still deploys when an agent depends on it
    // (§SPEC-AGENTSKILLS-02 co-deploy guarantee). Resolving the stem sets ONCE
    // here (rather than inside `deploy_all_skill_tiers`) lets the same sets
    // drive both the `select` override AND the resolution logging.
    let bundled_stems = list_source_stems(&plan.skill_source).unwrap_or_default();
    let user_stems = list_source_stems(&fw.user_skill_source_dir()).unwrap_or_default();
    let project_stems = list_project_custom_stems(&fw.claude_skills_dir()).unwrap_or_default();
    let co_deploy_skills = co_deploy_skill_set(declared_skills);
    log_declared_skills(declared_skills, &project_stems, &user_stems, &bundled_stems);

    // Claude Code reads `~/.claude/skills/` at startup. Skills carry no
    // inheritance, so this is a manifest-tracked content copy. The manifest's
    // skill-set selection restricts WHICH bundled skills deploy — OR'd with
    // `co_deploy_skills` (DOC-42); the user-custom tier is deployed in full and
    // overrides a same-named bundled skill; a skill hand-placed in the project's
    // `.claude/skills/` outranks both and is never overwritten. See
    // `core::skill_tiers`.
    crate::core::provisioning_stage::emit(
        crate::core::provisioning_stage::ProvisioningStage::DeployingSkills,
    );
    let stats = match deploy_all_skill_tiers(
        &plan.skill_source,
        &fw.user_skill_source_dir(),
        &fw.claude_skills_dir(),
        |name| plan.skill_selected(name) || co_deploy_skills.contains(name),
    ) {
        Ok(result) => result.stats,
        Err(err) => {
            tracing::error!(
                project_dir = %project_dir.display(),
                "skill deploy FAILED — session will launch WITHOUT the tm/mpm skill \
                 set: {err}. Identity/output-style provisioning continues regardless."
            );
            roster_errors.push(format!("skill deploy failed: {err}"));
            DeployStats::default()
        }
    };

    // #5224: the deploy above only WRITES, so a skill this binary stopped
    // shipping keeps its deployed directory and its ledger entry — and that
    // orphaned entry pins `tm doctor`'s `skill_staleness` check to Unknown.
    // Covers every deploy tier and logs per skill; never fails the launch,
    // because retirement is maintenance, not a precondition of starting.
    crate::core::skill_retire::retire_orphaned_skills(fw, Some(project_dir));

    stats
}