//! Agent lifecycle use cases (ARCHITECTURE §6, L6).
//!
//! These own the *project-agent* side (distinct from the profile side in
//! [`super::usecases`]): creating agents and their `.md` contexts under
//! `.ideai/`, listing/reading/updating them, and — the centrepiece —
//! [`LaunchAgent`], which resolves the agent's profile + context, applies the
//! profile's context-injection strategy, opens a PTY cell at the right `cwd` and
//! spawns the CLI.
//!
//! Every use case talks **only to ports** ([`AgentContextStore`], [`ProfileStore`],
//! [`AgentRuntime`], [`PtyPort`], [`FileSystem`], [`EventBus`]); none knows about
//! a concrete adapter or Tauri.

use std::sync::Arc;

use domain::ports::{
    AgentContextStore, AgentRuntime, ContextInjectionPlan, EventBus, FileSystem, PreparedContext,
    ProfileStore, PtyPort, RemotePath, SkillStore, SpawnSpec, StoreError,
};
use domain::{
    Agent, AgentId, AgentManifest, AgentOrigin, DomainEvent, ManifestEntry, MarkdownDoc, NodeId,
    Project, ProfileId, ProjectPath, PtySize, SessionKind, SessionStatus, Skill, TerminalSession,
};

use crate::error::AppError;
use crate::terminal::TerminalSessions;

/// Directory (relative to `.ideai/`) under which agent contexts are written.
const AGENTS_SUBDIR: &str = "agents";

// ---------------------------------------------------------------------------
// CreateAgentFromScratch
// ---------------------------------------------------------------------------

/// Input for [`CreateAgentFromScratch::execute`].
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct CreateAgentInput {
    /// The project that owns the agent.
    pub project: Project,
    /// Display name of the agent.
    pub name: String,
    /// Runtime profile the agent launches with.
    pub profile_id: ProfileId,
    /// Initial `.md` content (empty when `None`).
    pub initial_content: Option<String>,
}

/// Output of [`CreateAgentFromScratch::execute`].
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct CreateAgentOutput {
    /// The freshly-created agent.
    pub agent: Agent,
}

/// Creates a project agent from scratch: mints an id, derives a unique `.md`
/// path, records the manifest entry, then writes the (possibly empty) context.
pub struct CreateAgentFromScratch {
    contexts: Arc<dyn AgentContextStore>,
    ids: Arc<dyn domain::ports::IdGenerator>,
    events: Arc<dyn EventBus>,
}

impl CreateAgentFromScratch {
    /// Builds the use case from its injected ports.
    #[must_use]
    pub fn new(
        contexts: Arc<dyn AgentContextStore>,
        ids: Arc<dyn domain::ports::IdGenerator>,
        events: Arc<dyn EventBus>,
    ) -> Self {
        Self {
            contexts,
            ids,
            events,
        }
    }

    /// Executes creation.
    ///
    /// Ordering matters: the manifest entry is persisted **before** the context
    /// is written, because [`AgentContextStore::write_context`] resolves the
    /// on-disk path from the manifest.
    ///
    /// # Errors
    /// - [`AppError::Invalid`] if the name is empty or the manifest would become
    ///   inconsistent,
    /// - [`AppError::Store`] on persistence failure.
    pub async fn execute(&self, input: CreateAgentInput) -> Result<CreateAgentOutput, AppError> {
        let manifest = self.contexts.load_manifest(&input.project).await?;

        let id = AgentId::from_uuid(self.ids.new_uuid());
        let md_path = unique_md_path(&input.name, &manifest);

        let agent = Agent::new(
            id,
            input.name,
            md_path,
            input.profile_id,
            AgentOrigin::Scratch,
            false,
        )
        .map_err(|e| AppError::Invalid(e.to_string()))?;

        // Append the entry and re-validate the whole manifest (unique md_paths).
        let mut entries = manifest.entries;
        entries.push(ManifestEntry::from_agent(&agent));
        let manifest = AgentManifest::new(manifest.version, entries)
            .map_err(|e| AppError::Invalid(e.to_string()))?;
        self.contexts.save_manifest(&input.project, &manifest).await?;

        // Now the path resolves: write the initial context.
        let md = MarkdownDoc::new(input.initial_content.unwrap_or_default());
        self.contexts
            .write_context(&input.project, &agent.id, &md)
            .await?;

        self.events.publish(DomainEvent::LayoutChanged {
            project_id: input.project.id,
        });

        Ok(CreateAgentOutput { agent })
    }
}

// ---------------------------------------------------------------------------
// ListAgents
// ---------------------------------------------------------------------------

/// Input for [`ListAgents::execute`].
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct ListAgentsInput {
    /// The project whose agents to list.
    pub project: Project,
}

/// Output of [`ListAgents::execute`].
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct ListAgentsOutput {
    /// The project's agents (reconstructed from the manifest).
    pub agents: Vec<Agent>,
}

/// Lists a project's agents by reconstructing them from the manifest entries.
pub struct ListAgents {
    contexts: Arc<dyn AgentContextStore>,
}

impl ListAgents {
    /// Builds the use case from the [`AgentContextStore`] port.
    #[must_use]
    pub fn new(contexts: Arc<dyn AgentContextStore>) -> Self {
        Self { contexts }
    }

    /// Loads the manifest and folds each entry back into an [`Agent`].
    ///
    /// # Errors
    /// - [`AppError::Store`] on persistence failure,
    /// - [`AppError::Invalid`] if a persisted entry violates an agent invariant.
    pub async fn execute(&self, input: ListAgentsInput) -> Result<ListAgentsOutput, AppError> {
        let manifest = self.contexts.load_manifest(&input.project).await?;
        let agents = manifest
            .entries
            .iter()
            .map(|e| e.to_agent().map_err(|err| AppError::Invalid(err.to_string())))
            .collect::<Result<Vec<_>, _>>()?;
        Ok(ListAgentsOutput { agents })
    }
}

// ---------------------------------------------------------------------------
// ReadAgentContext / UpdateAgentContext
// ---------------------------------------------------------------------------

/// Input for [`ReadAgentContext::execute`].
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct ReadAgentContextInput {
    /// The owning project.
    pub project: Project,
    /// The agent whose `.md` to read.
    pub agent_id: AgentId,
}

/// Output of [`ReadAgentContext::execute`].
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct ReadAgentContextOutput {
    /// The agent's Markdown context.
    pub content: MarkdownDoc,
}

/// Reads an agent's `.md` context.
pub struct ReadAgentContext {
    contexts: Arc<dyn AgentContextStore>,
}

impl ReadAgentContext {
    /// Builds the use case.
    #[must_use]
    pub fn new(contexts: Arc<dyn AgentContextStore>) -> Self {
        Self { contexts }
    }

    /// Reads the context.
    ///
    /// # Errors
    /// - [`AppError::NotFound`] if the agent (or its `.md`) is unknown,
    /// - [`AppError::Store`] on persistence failure.
    pub async fn execute(
        &self,
        input: ReadAgentContextInput,
    ) -> Result<ReadAgentContextOutput, AppError> {
        let content = self
            .contexts
            .read_context(&input.project, &input.agent_id)
            .await?;
        Ok(ReadAgentContextOutput { content })
    }
}

/// Input for [`UpdateAgentContext::execute`].
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct UpdateAgentContextInput {
    /// The owning project.
    pub project: Project,
    /// The agent whose `.md` to overwrite.
    pub agent_id: AgentId,
    /// New Markdown content.
    pub content: String,
}

/// Overwrites an agent's `.md` context.
pub struct UpdateAgentContext {
    contexts: Arc<dyn AgentContextStore>,
}

impl UpdateAgentContext {
    /// Builds the use case.
    #[must_use]
    pub fn new(contexts: Arc<dyn AgentContextStore>) -> Self {
        Self { contexts }
    }

    /// Writes the new context.
    ///
    /// # Errors
    /// - [`AppError::NotFound`] if the agent is unknown,
    /// - [`AppError::Store`] on persistence failure.
    pub async fn execute(&self, input: UpdateAgentContextInput) -> Result<(), AppError> {
        let md = MarkdownDoc::new(input.content);
        self.contexts
            .write_context(&input.project, &input.agent_id, &md)
            .await?;
        Ok(())
    }
}

// ---------------------------------------------------------------------------
// DeleteAgent
// ---------------------------------------------------------------------------

/// Input for [`DeleteAgent::execute`].
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct DeleteAgentInput {
    /// The owning project.
    pub project: Project,
    /// The agent to remove.
    pub agent_id: AgentId,
}

/// Removes an agent from the project manifest.
///
/// The orphaned `.md` file is left on disk: the [`FileSystem`] port exposes no
/// delete, and keeping the file is the safe default (the user may want to recover
/// the context). Re-creating an agent with the same name reuses a fresh path.
pub struct DeleteAgent {
    contexts: Arc<dyn AgentContextStore>,
    events: Arc<dyn EventBus>,
}

impl DeleteAgent {
    /// Builds the use case.
    #[must_use]
    pub fn new(contexts: Arc<dyn AgentContextStore>, events: Arc<dyn EventBus>) -> Self {
        Self { contexts, events }
    }

    /// Drops the manifest entry for the agent.
    ///
    /// # Errors
    /// - [`AppError::NotFound`] if the agent is not in the manifest,
    /// - [`AppError::Store`] on persistence failure.
    pub async fn execute(&self, input: DeleteAgentInput) -> Result<(), AppError> {
        let manifest = self.contexts.load_manifest(&input.project).await?;
        let before = manifest.entries.len();
        let entries: Vec<ManifestEntry> = manifest
            .entries
            .into_iter()
            .filter(|e| e.agent_id != input.agent_id)
            .collect();
        if entries.len() == before {
            return Err(AppError::NotFound(format!("agent {}", input.agent_id)));
        }
        let manifest = AgentManifest::new(manifest.version, entries)
            .map_err(|e| AppError::Invalid(e.to_string()))?;
        self.contexts.save_manifest(&input.project, &manifest).await?;
        self.events.publish(DomainEvent::LayoutChanged {
            project_id: input.project.id,
        });
        Ok(())
    }
}

// ---------------------------------------------------------------------------
// LaunchAgent
// ---------------------------------------------------------------------------

/// Input for [`LaunchAgent::execute`].
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct LaunchAgentInput {
    /// The owning project.
    pub project: Project,
    /// The agent to launch.
    pub agent_id: AgentId,
    /// Initial terminal height in rows.
    pub rows: u16,
    /// Initial terminal width in columns.
    pub cols: u16,
    /// The layout leaf hosting the session (a fresh node when `None`).
    pub node_id: Option<NodeId>,
}

/// Output of [`LaunchAgent::execute`].
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct LaunchAgentOutput {
    /// The created agent terminal session.
    pub session: TerminalSession,
}

/// Launches an agent: resolve profile + context, prepare the invocation, apply
/// the context-injection plan, open a PTY at the resolved `cwd`, spawn the CLI.
///
/// This is the orchestrating use case of L6 and therefore consumes several ports
/// — each only for the slice it needs (Interface Segregation): the context store
/// (agent `.md` + manifest), the profile store (resolve the runtime), the runtime
/// (build the [`SpawnSpec`]), the filesystem (materialise a `conventionFile`
/// context), and the PTY (spawn + optional stdin injection).
pub struct LaunchAgent {
    contexts: Arc<dyn AgentContextStore>,
    profiles: Arc<dyn ProfileStore>,
    runtime: Arc<dyn AgentRuntime>,
    fs: Arc<dyn FileSystem>,
    pty: Arc<dyn PtyPort>,
    skills: Arc<dyn SkillStore>,
    sessions: Arc<TerminalSessions>,
    events: Arc<dyn EventBus>,
}

impl LaunchAgent {
    /// Builds the use case from its injected ports.
    #[must_use]
    #[allow(clippy::too_many_arguments)]
    pub fn new(
        contexts: Arc<dyn AgentContextStore>,
        profiles: Arc<dyn ProfileStore>,
        runtime: Arc<dyn AgentRuntime>,
        fs: Arc<dyn FileSystem>,
        pty: Arc<dyn PtyPort>,
        skills: Arc<dyn SkillStore>,
        sessions: Arc<TerminalSessions>,
        events: Arc<dyn EventBus>,
    ) -> Self {
        Self {
            contexts,
            profiles,
            runtime,
            fs,
            pty,
            skills,
            sessions,
            events,
        }
    }

    /// Resolves the Markdown bodies of an agent's assigned skills, in the
    /// **manifest order** (deterministic). A skill that no longer exists in its
    /// store (deleted out from under the assignment) is silently skipped — a
    /// dangling [`domain::SkillRef`] must not block a launch.
    ///
    /// # Errors
    /// [`AppError::Store`] on any store failure other than a missing skill.
    async fn resolve_skills(
        &self,
        agent: &Agent,
        root: &ProjectPath,
    ) -> Result<Vec<Skill>, AppError> {
        let mut out = Vec::with_capacity(agent.skills.len());
        for skill_ref in &agent.skills {
            match self.skills.get(skill_ref.scope, root, skill_ref.skill_id).await {
                Ok(skill) => out.push(skill),
                Err(StoreError::NotFound) => {}
                Err(e) => return Err(e.into()),
            }
        }
        Ok(out)
    }

    /// Executes the launch.
    ///
    /// Step order is contractually significant (and unit-tested): resolve the
    /// agent + context, **`prepare_invocation`**, **apply the injection plan**
    /// (write a `conventionFile` / set an env var), then **`pty.spawn`** at the
    /// resolved `cwd`, and finally pipe the context on stdin for the `Stdin`
    /// strategy.
    ///
    /// # Errors
    /// - [`AppError::NotFound`] if the agent or its profile is unknown,
    /// - [`AppError::Invalid`] for a zero-sized terminal,
    /// - [`AppError::Store`] / [`AppError::FileSystem`] / [`AppError::Process`] on
    ///   the respective port failures.
    pub async fn execute(&self, input: LaunchAgentInput) -> Result<LaunchAgentOutput, AppError> {
        let size =
            PtySize::new(input.rows, input.cols).map_err(|e| AppError::Invalid(e.to_string()))?;

        // 1. Resolve the agent from the manifest (name + profile + md_path).
        let manifest = self.contexts.load_manifest(&input.project).await?;
        let entry = manifest
            .entries
            .iter()
            .find(|e| e.agent_id == input.agent_id)
            .ok_or_else(|| AppError::NotFound(format!("agent {}", input.agent_id)))?;
        let agent = entry
            .to_agent()
            .map_err(|e| AppError::Invalid(e.to_string()))?;

        // 2. Read its context and resolve its profile.
        let content = self
            .contexts
            .read_context(&input.project, &agent.id)
            .await?;
        let profile = self
            .profiles
            .list()
            .await?
            .into_iter()
            .find(|p| p.id == agent.profile_id)
            .ok_or_else(|| {
                AppError::NotFound(format!("profile {} for agent", agent.profile_id))
            })?;

        // 3. Compute and create the agent's isolated run directory
        //    `<root>/.ideai/run/<agent-id>/` (ARCHITECTURE §14.1). The PTY cwd is
        //    *never* the project root: each agent gets its own directory so that N
        //    instances of the same profile never collide on a single conventional
        //    file (CLAUDE.md, …). This is the only I/O in the cwd resolution; the
        //    runtime's `prepare_invocation` stays pure.
        let run_dir = agent_run_dir(&input.project.root, &agent.id)
            .map_err(|e| AppError::Invalid(e.to_string()))?;
        self.fs
            .create_dir_all(&RemotePath::new(run_dir.as_str().to_owned()))
            .await?;

        // 4. Prepare the invocation (pure): command + args + injection plan + cwd.
        //    The run dir is passed as the cwd base; the profile's `{agentRunDir}`
        //    placeholder resolves against it.
        let prepared = PreparedContext {
            content: content.clone(),
            relative_path: agent.context_path.clone(),
        };
        let mut spec = self
            .runtime
            .prepare_invocation(&profile, &prepared, &run_dir)?;

        // 5. Resolve the agent's assigned skills (their `.md` bodies), then apply
        //    the injection plan side effects *before* spawning.
        let skills = self.resolve_skills(&agent, &input.project.root).await?;
        self.apply_injection(&input.project, &agent.context_path, &content, &skills, &mut spec)
            .await?;

        // 6. Spawn the PTY at the resolved cwd; adopt its session id everywhere.
        let handle = self.pty.spawn(spec.clone(), size).await?;
        let session_id = handle.session_id;

        // 7. For the Stdin strategy, pipe the context once the PTY is live.
        if matches!(spec.context_plan, Some(ContextInjectionPlan::Stdin)) {
            self.pty.write(&handle, content.as_str().as_bytes())?;
        }

        let node_id = input.node_id.unwrap_or_else(NodeId::new_random);
        let mut session = TerminalSession::starting(
            session_id,
            node_id,
            spec.cwd.clone(),
            SessionKind::Agent {
                agent_id: agent.id,
            },
            size,
        );
        session.status = SessionStatus::Running;
        self.sessions.insert(handle, session.clone());

        self.events.publish(DomainEvent::AgentLaunched {
            agent_id: agent.id,
            session_id,
        });

        Ok(LaunchAgentOutput { session })
    }

    /// Applies the context-injection plan that must happen *before* spawn:
    /// materialising a `conventionFile` context (write the `.md` to `<cwd>/target`)
    /// or attaching the on-disk context path to an environment variable. `Args` is
    /// already folded into the spec by the runtime; `Stdin` is handled post-spawn.
    async fn apply_injection(
        &self,
        project: &Project,
        context_rel_path: &str,
        content: &MarkdownDoc,
        skills: &[Skill],
        spec: &mut SpawnSpec,
    ) -> Result<(), AppError> {
        match spec.context_plan.clone() {
            Some(ContextInjectionPlan::File { target }) => {
                // conventionFile (ARCHITECTURE §14.1): IdeA *generates* the
                // conventional file (e.g. CLAUDE.md) inside the agent's isolated
                // run directory — `spec.cwd` is that run dir, never the project
                // root, so there is zero collision between agents. The document is
                // composed: an absolute project-root header (so the agent knows
                // where to operate, since its cwd is *not* the root), the agent's
                // persona `.md`, then the bodies of its assigned skills (§14.2).
                let document =
                    compose_convention_file(project.root.as_str(), content.as_str(), skills);
                let path = RemotePath::new(join(&spec.cwd, &target));
                self.fs.write(&path, document.as_bytes()).await?;
            }
            Some(ContextInjectionPlan::Env { var }) => {
                // Hand the CLI the absolute path of the agent's `.md` (which lives at
                // `<root>/.ideai/<context_rel_path>`) via the environment variable.
                let abspath = join(&project.root, &format!(".ideai/{context_rel_path}"));
                spec.env.push((var, abspath));
            }
            // Args were folded into spec.args by prepare_invocation; Stdin is
            // applied after the PTY is live.
            Some(ContextInjectionPlan::Args { .. }) | Some(ContextInjectionPlan::Stdin) | None => {}
        }
        Ok(())
    }
}

/// Builds an absolute path string by joining a [`ProjectPath`] with a relative
/// segment using a POSIX separator.
fn join(base: &ProjectPath, rel: &str) -> String {
    let b = base.as_str().trim_end_matches(['/', '\\']);
    format!("{b}/{rel}")
}

/// Computes an agent's isolated run directory `<root>/.ideai/run/<agent-id>/`
/// (ARCHITECTURE §14.1). This is the PTY cwd for the agent — never the project
/// root — guaranteeing that two distinct agents on the same project root get two
/// distinct cwd (the anti-collision contract).
///
/// # Errors
/// Propagates [`DomainError`](domain::error::DomainError) if the joined path is
/// not a valid [`ProjectPath`] (should not happen for an absolute project root).
fn agent_run_dir(root: &ProjectPath, agent_id: &AgentId) -> Result<ProjectPath, domain::error::DomainError> {
    ProjectPath::new(join(root, &format!(".ideai/run/{agent_id}")))
}

/// Composes the convention file IdeA writes into an agent's run directory: an
/// absolute project-root header (the agent's cwd is the run dir, *not* the root,
/// so it must be told where to work), the agent's persona `.md`, then the bodies
/// of its assigned `skills` under a `# Skills` section (ARCHITECTURE §14.2).
///
/// Skills are emitted in the order given (the caller passes them in manifest
/// order, making the output deterministic); each is introduced by a `##` header
/// carrying its name. When `skills` is empty the section is omitted entirely, so
/// an agent with no skills gets exactly the previous document.
///
/// Kept as a **pure** function (no I/O) so it is unit-testable in isolation.
#[must_use]
pub(crate) fn compose_convention_file(project_root: &str, agent_md: &str, skills: &[Skill]) -> String {
    let mut out = String::new();
    out.push_str("# Project root\n\n");
    out.push_str(project_root);
    out.push_str("\n\nTous tes travaux portent sur ce project root (chemin absolu ci-dessus). ");
    out.push_str(
        "Ton répertoire courant est un dossier d'exécution isolé (`.ideai/run/<agent>/`) ; \
         opère sur le project root, pas sur ce dossier.\n\n",
    );
    out.push_str("---\n\n");
    out.push_str(agent_md);

    if !skills.is_empty() {
        out.push_str("\n\n---\n\n# Skills\n");
        for skill in skills {
            out.push_str("\n## ");
            out.push_str(&skill.name);
            out.push_str("\n\n");
            out.push_str(skill.content_md.as_str());
            out.push('\n');
        }
    }
    out
}

/// Derives a unique, filesystem-safe `md_path` (`agents/<slug>.md`) for a new
/// agent, disambiguating against the manifest's existing paths with a numeric
/// suffix when needed. Shared with the template-driven agent creation (L7).
pub(crate) fn unique_md_path(name: &str, manifest: &AgentManifest) -> String {
    let slug = slugify(name);
    let base = if slug.is_empty() { "agent".to_owned() } else { slug };
    let mut candidate = format!("{AGENTS_SUBDIR}/{base}.md");
    let mut n = 2;
    while manifest.entries.iter().any(|e| e.md_path == candidate) {
        candidate = format!("{AGENTS_SUBDIR}/{base}-{n}.md");
        n += 1;
    }
    candidate
}

/// Lowercases and slugifies a display name into a safe file stem
/// (`[a-z0-9-]`), collapsing runs of separators.
fn slugify(name: &str) -> String {
    let mut out = String::with_capacity(name.len());
    let mut prev_dash = false;
    for ch in name.trim().chars() {
        if ch.is_ascii_alphanumeric() {
            out.push(ch.to_ascii_lowercase());
            prev_dash = false;
        } else if !prev_dash {
            out.push('-');
            prev_dash = true;
        }
    }
    out.trim_matches('-').to_owned()
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn agent_run_dir_is_under_ideai_run_and_unique_per_agent() {
        let root = ProjectPath::new("/home/me/proj").unwrap();
        let a = AgentId::from_uuid(uuid::Uuid::from_u128(1));
        let b = AgentId::from_uuid(uuid::Uuid::from_u128(2));

        let dir_a = agent_run_dir(&root, &a).unwrap();
        let dir_b = agent_run_dir(&root, &b).unwrap();

        assert_eq!(dir_a.as_str(), format!("/home/me/proj/.ideai/run/{a}"));
        assert_ne!(dir_a, dir_b, "distinct agents → distinct run dirs");
        // Never the project root.
        assert_ne!(dir_a.as_str(), "/home/me/proj");
    }

    #[test]
    fn compose_convention_file_carries_root_then_persona() {
        let doc = compose_convention_file("/abs/project/root", "# Persona\n\nDo things.", &[]);

        // Absolute project root present.
        assert!(doc.contains("/abs/project/root"));
        // Persona present.
        assert!(doc.contains("# Persona"));
        assert!(doc.contains("Do things."));
        // Root header precedes the persona body (ordering of the composition).
        let root_at = doc.find("/abs/project/root").unwrap();
        let persona_at = doc.find("# Persona").unwrap();
        assert!(root_at < persona_at, "root header must precede the persona");
        // No skills ⇒ no Skills section.
        assert!(!doc.contains("# Skills"));
    }

    #[test]
    fn compose_convention_file_appends_assigned_skills_in_order() {
        let s = |n: u128, name: &str, body: &str| {
            Skill::new(
                domain::SkillId::from_uuid(uuid::Uuid::from_u128(n)),
                name,
                MarkdownDoc::new(body),
                domain::SkillScope::Global,
            )
            .unwrap()
        };
        let doc = compose_convention_file(
            "/root",
            "# Persona",
            &[s(1, "refactor", "REFAC_BODY"), s(2, "review", "REVIEW_BODY")],
        );

        // Both skill bodies present, after the persona.
        assert!(doc.contains("REFAC_BODY"));
        assert!(doc.contains("REVIEW_BODY"));
        let persona_at = doc.find("# Persona").unwrap();
        let refac_at = doc.find("REFAC_BODY").unwrap();
        let review_at = doc.find("REVIEW_BODY").unwrap();
        assert!(persona_at < refac_at, "skills come after the persona");
        // Deterministic order: first assigned skill precedes the second.
        assert!(refac_at < review_at, "skills emitted in the given order");
        // Skill names surface as sub-headers.
        assert!(doc.contains("## refactor"));
        assert!(doc.contains("## review"));
    }
}