leviath_cli/commands/setup/

state.rs

//! The wizard's state: what step we're on, what's been chosen, and how a
//! choice turns back into a [`SetupPlan`].
//!
//! Deliberately free of drawing and of key handling - those are `render` and
//! `input`. Everything here is ordinary data and pure transitions, so the whole
//! flow is testable without a terminal.

use std::collections::HashMap;

use leviath_mcp::MCPServerConfig;
use tokio::sync::mpsc;

use super::catalog::{self, Credential, Provider};
use super::import::{self, Candidate};
use super::plan::SetupPlan;
use super::verify::Outcome;
use crate::bundled::{AgentAction, BundledAgent};
use crate::config::Config;

/// The wizard's screens, in order.
#[derive(Debug, Clone, Copy, PartialEq, Eq, PartialOrd, Ord)]
pub enum Step {
    Welcome,
    Providers,
    ProviderDetail,
    Defaults,
    Limits,
    Agents,
    Mcp,
    Review,
}

impl Step {
    /// Every step, in order.
    pub const ALL: [Step; 8] = [
        Step::Welcome,
        Step::Providers,
        Step::ProviderDetail,
        Step::Defaults,
        Step::Limits,
        Step::Agents,
        Step::Mcp,
        Step::Review,
    ];

    /// Title shown in the header.
    pub fn title(self) -> &'static str {
        match self {
            Step::Welcome => "Welcome",
            Step::Providers => "Providers",
            Step::ProviderDetail => "Credentials",
            Step::Defaults => "Defaults",
            Step::Limits => "Limits",
            Step::Agents => "Agents",
            Step::Mcp => "MCP servers",
            Step::Review => "Review",
        }
    }

    /// Position in [`Self::ALL`].
    pub fn index(self) -> usize {
        Self::ALL
            .iter()
            .position(|s| *s == self)
            .expect("every step is in ALL")
    }
}

/// One row of the provider pick-list.
#[derive(Debug, Clone)]
pub struct ProviderRow {
    pub provider: Provider,
    pub selected: bool,
    /// The credential as typed. Empty means "no value".
    pub value: String,
    /// The credential is already in the environment, under this variable, and
    /// is not being written to the config.
    pub from_env: Option<&'static str>,
    /// Reasoning effort, for the Claude Code transport only.
    pub effort: usize,
    pub outcome: Outcome,
    /// A verification is in flight.
    pub checking: bool,
}

impl ProviderRow {
    /// Whether this provider has something to verify.
    pub fn has_credential(&self) -> bool {
        match self.provider.credential {
            Credential::ApiKey => !self.value.is_empty() || self.from_env.is_some(),
            // Ollama and the Claude Code transport need no key; selecting them
            // is the whole configuration, so they are always checkable.
            Credential::BaseUrl | Credential::None => true,
        }
    }
}

/// One row of the blueprint list.
#[derive(Debug, Clone)]
pub struct AgentRow {
    pub agent: &'static BundledAgent,
    pub action: AgentAction,
    pub selected: bool,
}

/// One importable MCP server.
#[derive(Debug, Clone)]
pub struct McpRow {
    pub candidate: Candidate,
    /// Which harness it came from.
    pub source: String,
    pub selected: bool,
    /// A server of this name is already in the Leviath config.
    pub collides: bool,
    /// The name it will actually be stored under, after collision handling.
    pub name: String,
}

/// A single editable setting on the Defaults / Limits screens.
#[derive(Debug, Clone)]
pub struct Field {
    pub label: &'static str,
    pub help: &'static str,
    pub value: FieldValue,
}

/// The kinds of setting the wizard edits, and therefore the ways a key press
/// can mean something.
#[derive(Debug, Clone, PartialEq, Eq)]
pub enum FieldValue {
    /// A whole number. `None` means unset.
    Number(Option<u64>),
    /// A toggle.
    Bool(bool),
    /// One of a fixed list.
    Choice { options: Vec<String>, index: usize },
}

impl FieldValue {
    /// How the value reads on screen.
    pub fn display(&self) -> String {
        match self {
            Self::Number(None) => "(unset)".to_string(),
            Self::Number(Some(n)) => n.to_string(),
            Self::Bool(true) => "yes".to_string(),
            Self::Bool(false) => "no".to_string(),
            Self::Choice { options, index } => match options.get(*index) {
                Some(chosen) => chosen.clone(),
                None => "(none)".to_string(),
            },
        }
    }

    /// The options of a choice field; empty for any other kind.
    pub fn options(&self) -> &[String] {
        match self {
            Self::Choice { options, .. } => options,
            Self::Number(_) | Self::Bool(_) => &[],
        }
    }
}

/// Asked of the background verifier.
#[derive(Debug, Clone)]
pub struct VerifyRequest {
    pub provider_id: String,
    pub creds: leviath_runtime::provider_creds::ProviderCreds,
}

/// Answered by the background verifier.
#[derive(Debug, Clone)]
pub struct VerifyReply {
    pub provider_id: String,
    pub outcome: Outcome,
}

/// Where the text being typed goes when it is committed.
#[derive(Debug, Clone, PartialEq, Eq)]
pub enum EditTarget {
    /// The credential of the provider at this index in `providers`.
    Credential(usize),
    /// The field at this index of the current step's fields.
    Field(usize),
}

/// An in-progress text edit.
#[derive(Debug, Clone)]
pub struct Edit {
    pub target: EditTarget,
    pub buffer: String,
    /// Draw the buffer masked. Set for API keys.
    pub masked: bool,
}

/// The whole wizard.
pub struct Wizard {
    pub step: Step,
    /// Selected row within the current step.
    pub cursor: usize,
    pub providers: Vec<ProviderRow>,
    /// Which selected provider the credential screen is showing.
    pub detail: usize,
    pub defaults: Vec<Field>,
    pub limits: Vec<Field>,
    pub agents: Vec<AgentRow>,
    pub mcp: Vec<McpRow>,
    pub mcp_scan_errors: Vec<String>,
    pub edit: Option<Edit>,
    /// Show credentials in clear text.
    pub reveal: bool,
    pub show_help: bool,
    /// The Claude Code terms-of-service confirmation is on screen, and is the
    /// only thing keys mean until it is answered.
    pub show_tos_confirm: bool,
    /// The user has acknowledged the Claude Code transport's terms risk. A
    /// hard gate on saving: the transport cannot be written to the config
    /// without it, and deselecting the transport withdraws it.
    pub claude_code_tos_accepted: bool,
    pub should_quit: bool,
    /// Set once the plan has been applied, so the loop knows to stop.
    pub finished: bool,
    /// A one-line status message.
    pub message: Option<String>,
    /// The config as loaded *from the file*, which is what the plan is
    /// diffed against and built on.
    pub base: Config,
    /// Credentials present only in the environment. Shown, never written.
    pub env_only: HashMap<&'static str, String>,
    /// Opens a provider's signup page. Injected rather than called directly:
    /// `lev dash` once had a unit test launch a real browser, and this is the
    /// same shape of hazard.
    pub opener: leviath_mcp::BrowserOpener,
    pub verify_tx: mpsc::UnboundedSender<VerifyRequest>,
    verify_rx: Option<mpsc::UnboundedReceiver<VerifyRequest>>,
    reply_tx: mpsc::UnboundedSender<VerifyReply>,
    pub reply_rx: mpsc::UnboundedReceiver<VerifyReply>,
    /// Tick counter, for the spinner.
    pub ticks: u64,
}

/// The environment variables the wizard reports as already-supplying a
/// credential, paired with their provider.
fn env_credentials(lookup: &dyn Fn(&str) -> Option<String>) -> HashMap<&'static str, String> {
    catalog::providers()
        .iter()
        .filter_map(|p| {
            let var = p.env_var?;
            let value = lookup(var)?;
            (!value.is_empty()).then_some((var, value))
        })
        .collect()
}

impl Wizard {
    /// Build the wizard from the config *file* and the surrounding environment.
    ///
    /// `base` must come from reading the file, not from `Config::load()`:
    /// `load` folds `$ANTHROPIC_API_KEY` and friends into the struct, and the
    /// old wizard then re-serialized the whole thing - silently writing a key
    /// the user had deliberately kept in their environment into
    /// `~/.leviath/config.toml`. Environment-supplied credentials are tracked
    /// separately in `env_only` and shown as such.
    pub fn new(
        base: Config,
        env_lookup: &dyn Fn(&str) -> Option<String>,
        candidates: Vec<(String, Candidate)>,
        scan_errors: Vec<String>,
        agents_dir: &std::path::Path,
        opener: leviath_mcp::BrowserOpener,
    ) -> Self {
        let env_only = env_credentials(env_lookup);

        let providers = catalog::providers()
            .into_iter()
            .map(|provider| {
                let stored = catalog::stored_credential(&base, provider.id);
                let from_env = provider
                    .env_var
                    .filter(|v| stored.is_none() && env_only.contains_key(v));
                ProviderRow {
                    selected: catalog::is_configured(&base, provider.id) || from_env.is_some(),
                    value: stored.unwrap_or_default(),
                    from_env,
                    effort: effort_index(base.providers.claude_code_effort.as_deref()),
                    outcome: Outcome::Skipped,
                    checking: false,
                    provider,
                }
            })
            .collect();

        let agents = crate::bundled::plan_agent_actions(agents_dir)
            .into_iter()
            .map(|(agent, action)| AgentRow {
                selected: action.is_change(),
                agent,
                action,
            })
            .collect();

        let mcp = candidates
            .into_iter()
            .map(|(source, candidate)| {
                let collides =
                    import::already_configured(&base.mcp_servers, &candidate.config.name);
                let name = import::dedup_name(&base.mcp_servers, &candidate.config.name);
                McpRow {
                    // A server already configured under this name is offered
                    // unchecked: the user has it, and silently adding a second
                    // copy under a suffixed name is not what "import" means.
                    selected: !collides,
                    source,
                    collides,
                    name,
                    candidate,
                }
            })
            .collect();

        let (verify_tx, verify_rx) = mpsc::unbounded_channel();
        let (reply_tx, reply_rx) = mpsc::unbounded_channel();

        let mut wizard = Self {
            step: Step::Welcome,
            cursor: 0,
            providers,
            detail: 0,
            defaults: Vec::new(),
            limits: limits_fields(&base),
            agents,
            mcp,
            mcp_scan_errors: scan_errors,
            edit: None,
            reveal: false,
            show_help: false,
            show_tos_confirm: false,
            claude_code_tos_accepted: false,
            should_quit: false,
            finished: false,
            message: None,
            base,
            env_only,
            opener,
            verify_tx,
            verify_rx: Some(verify_rx),
            reply_tx,
            reply_rx,
            ticks: 0,
        };
        wizard.rebuild_defaults();
        wizard
    }

    /// Hand the background verifier loop its channel ends. Returns `None` if
    /// already taken.
    pub fn take_verify_ends(
        &mut self,
    ) -> Option<(
        mpsc::UnboundedReceiver<VerifyRequest>,
        mpsc::UnboundedSender<VerifyReply>,
    )> {
        self.verify_rx.take().map(|rx| (rx, self.reply_tx.clone()))
    }

    // ── Rows and navigation ─────────────────────────────────────────────────

    /// Providers the user picked, in table order.
    pub fn selected_providers(&self) -> Vec<usize> {
        self.providers
            .iter()
            .enumerate()
            .filter(|(_, r)| r.selected)
            .map(|(i, _)| i)
            .collect()
    }

    /// The provider row the credential screen is currently showing.
    pub fn detail_row(&self) -> Option<usize> {
        self.selected_providers().get(self.detail).copied()
    }

    /// Whether the Claude Code transport is one of the picked providers.
    pub fn claude_code_selected(&self) -> bool {
        self.providers
            .iter()
            .any(|r| r.selected && r.provider.id == "claude-code")
    }

    /// Whether saving must first ask the user to acknowledge Anthropic's
    /// terms. Enabling the transport routes inference through a subscription
    /// session, so the risk is confirmed once, explicitly, rather than being
    /// buried in a paragraph nobody reads.
    pub fn needs_tos_confirmation(&self) -> bool {
        self.claude_code_selected() && !self.claude_code_tos_accepted
    }

    /// The fields the current step edits, if it edits fields.
    pub fn fields(&self) -> &[Field] {
        match self.step {
            Step::Defaults => &self.defaults,
            Step::Limits => &self.limits,
            _ => &[],
        }
    }

    pub(super) fn fields_mut(&mut self) -> Option<&mut Vec<Field>> {
        match self.step {
            Step::Defaults => Some(&mut self.defaults),
            Step::Limits => Some(&mut self.limits),
            _ => None,
        }
    }

    /// How many selectable rows the current step has.
    pub fn row_count(&self) -> usize {
        match self.step {
            Step::Welcome | Step::Review => 0,
            Step::Providers => self.providers.len(),
            Step::ProviderDetail => usize::from(self.detail_row().is_some()),
            Step::Defaults => self.defaults.len(),
            Step::Limits => self.limits.len(),
            Step::Agents => self.agents.len(),
            Step::Mcp => self.mcp.len(),
        }
    }

    /// Move the selection, clamped to the step's rows.
    pub fn move_cursor(&mut self, delta: isize) {
        let count = self.row_count();
        if count == 0 {
            self.cursor = 0;
            return;
        }
        let next = self.cursor as isize + delta;
        self.cursor = next.clamp(0, count as isize - 1) as usize;
    }

    /// Advance to the next step, skipping ones with nothing to show.
    pub fn next_step(&mut self) {
        let mut index = self.step.index();
        while index + 1 < Step::ALL.len() {
            index += 1;
            let step = Step::ALL[index];
            if !self.is_empty_step(step) {
                self.enter(step);
                return;
            }
        }
        // Past the last step: the Review screen's action is to save.
        self.enter(Step::Review);
    }

    /// Go back a step, skipping empty ones. No-op on the first.
    pub fn prev_step(&mut self) {
        let mut index = self.step.index();
        while index > 0 {
            index -= 1;
            let step = Step::ALL[index];
            if !self.is_empty_step(step) {
                self.enter(step);
                return;
            }
        }
    }

    /// Whether a step has nothing worth showing, and should be skipped.
    ///
    /// Only the two discovery-driven screens can be empty: nobody should have
    /// to press Enter through "no MCP servers found" on a clean machine.
    fn is_empty_step(&self, step: Step) -> bool {
        match step {
            Step::Mcp => self.mcp.is_empty() && self.mcp_scan_errors.is_empty(),
            Step::ProviderDetail => self.detail_row().is_none(),
            _ => false,
        }
    }

    /// Switch to `step`, resetting per-step state.
    pub fn enter(&mut self, step: Step) {
        self.step = step;
        self.cursor = 0;
        self.edit = None;
        if step == Step::Defaults {
            // The model picker is populated by verification, which may have
            // finished since the last visit.
            self.rebuild_defaults();
        }
    }

    /// Within the credential screen, move to the next selected provider;
    /// returns false when there is no next one.
    pub fn next_detail(&mut self) -> bool {
        if self.detail + 1 < self.selected_providers().len() {
            self.detail += 1;
            self.cursor = 0;
            self.edit = None;
            return true;
        }
        false
    }

    /// The reverse of [`Self::next_detail`].
    pub fn prev_detail(&mut self) -> bool {
        if self.detail > 0 {
            self.detail -= 1;
            self.cursor = 0;
            self.edit = None;
            return true;
        }
        false
    }

    // ── Verification ────────────────────────────────────────────────────────

    /// Ask the background verifier about the provider at `index`.
    ///
    /// A provider with nothing to check is left alone rather than queued: a
    /// blank API key would fail with a message about the key rather than saying
    /// the obvious, that none was given.
    pub fn request_verification(&mut self, index: usize) {
        let Some(row) = self.providers.get_mut(index) else {
            return;
        };
        if !row.has_credential() {
            row.outcome = Outcome::Skipped;
            return;
        }
        let id = row.provider.id.to_string();
        let key = if row.value.is_empty() {
            self.env_only
                .get(row.provider.env_var.unwrap_or_default())
                .cloned()
        } else {
            Some(row.value.clone())
        };
        let base_url = (row.provider.credential == Credential::BaseUrl).then(|| {
            if row.value.is_empty() {
                catalog::DEFAULT_OLLAMA_URL.to_string()
            } else {
                row.value.clone()
            }
        });
        row.checking = true;

        let creds = leviath_runtime::provider_creds::ProviderCreds {
            name: id.clone(),
            api_key: base_url.is_none().then_some(key).flatten(),
            base_url,
            model_capabilities: HashMap::new(),
            request_timeout_secs: Some(20),
            rate_limit: None,
            options: HashMap::new(),
        };
        // A closed receiver means the background task is gone; the row simply
        // stays "checking" and nothing else breaks.
        let _ = self.verify_tx.send(VerifyRequest {
            provider_id: id,
            creds,
        });
    }

    /// Ask about every selected provider at once.
    pub fn verify_all(&mut self) {
        for index in self.selected_providers() {
            self.request_verification(index);
        }
    }

    /// Take whatever the background verifier has answered.
    pub fn drain_verifications(&mut self) {
        let mut landed = false;
        while let Ok(reply) = self.reply_rx.try_recv() {
            if let Some(row) = self
                .providers
                .iter_mut()
                .find(|r| r.provider.id == reply.provider_id)
            {
                row.checking = false;
                row.outcome = reply.outcome;
                landed = true;
            }
        }
        // A reply carries the model list, and the picker was built from
        // whatever had arrived when the screen opened. Without this, moving on
        // from a credential and straight into Defaults shows an empty picker
        // for the provider that was verified half a second ago. Rebuilding
        // keeps the current selection, so nothing the user chose is lost.
        if landed && self.step == Step::Defaults {
            self.rebuild_defaults();
        }
    }

    /// Every model id any provider reported, deduplicated, for the picker.
    pub fn discovered_models(&self) -> Vec<String> {
        let mut models: Vec<String> = self
            .providers
            .iter()
            .filter(|r| r.selected)
            .flat_map(|r| r.outcome.models().iter().cloned())
            .collect();
        models.sort();
        models.dedup();
        models
    }

    // ── Forms ───────────────────────────────────────────────────────────────

    /// Rebuild the Defaults screen. Called on entry, since both the provider
    /// list and the discovered models can change between visits.
    pub fn rebuild_defaults(&mut self) {
        let chosen = self.current_default_provider();
        let providers: Vec<String> = self
            .selected_providers()
            .iter()
            .map(|i| self.providers[*i].provider.id.to_string())
            .collect();
        // Fall back to whatever is configured when nothing is selected, so the
        // field is never empty.
        let providers = if providers.is_empty() {
            vec![self.base.default_provider.clone()]
        } else {
            providers
        };
        let index = providers.iter().position(|p| *p == chosen).unwrap_or(0);

        let mut models = vec!["(provider default)".to_string()];
        models.extend(self.discovered_models());
        let current_model = self
            .current_default_model()
            .unwrap_or_else(|| "(provider default)".to_string());
        if !models.contains(&current_model) {
            models.push(current_model.clone());
        }
        let model_index = models
            .iter()
            .position(|m| *m == current_model)
            .unwrap_or_default();

        let timeout = self.current_request_timeout();
        self.defaults = vec![
            Field {
                label: "Default provider",
                help: "Used by any blueprint that allows a user default.",
                value: FieldValue::Choice {
                    options: providers,
                    index,
                },
            },
            Field {
                label: "Default model",
                help: "Filled in from the models your providers reported.",
                value: FieldValue::Choice {
                    options: models,
                    index: model_index,
                },
            },
            Field {
                label: "Request timeout (seconds)",
                help: "How long to wait on one inference. Unset uses the provider default.",
                value: FieldValue::Number(timeout),
            },
        ];
        // Re-pick the concurrency default now that the provider choice is
        // settled. Doing this only on an arrow press missed the commonest
        // Ollama case entirely: when it is the *only* provider selected it is
        // already at index 0, nobody ever presses an arrow, and the limit
        // stayed at the hosted-API default of 8.
        self.apply_provider_concurrency_default();
    }

    /// The default provider as it currently stands in the form, or the base
    /// config's value before the form exists.
    fn current_default_provider(&self) -> String {
        match self.defaults.first().map(|f| &f.value) {
            Some(FieldValue::Choice { options, index }) => match options.get(*index) {
                Some(chosen) => chosen.clone(),
                None => self.base.default_provider.clone(),
            },
            _ => self.base.default_provider.clone(),
        }
    }

    fn current_default_model(&self) -> Option<String> {
        match self.defaults.get(1).map(|f| &f.value) {
            Some(FieldValue::Choice { options, index }) => options.get(*index).cloned(),
            _ => self.base.default_model.clone(),
        }
    }

    fn current_request_timeout(&self) -> Option<u64> {
        match self.defaults.get(2).map(|f| &f.value) {
            Some(FieldValue::Number(n)) => *n,
            _ => self.base.request_timeout_secs,
        }
    }

    /// Set the concurrency default that suits the chosen provider.
    ///
    /// A local Ollama serves one model at a time, so eight concurrent
    /// inferences against it queue and thrash rather than going faster. Only
    /// applied while the field still holds the general default, so a number the
    /// user typed is never overwritten.
    pub fn apply_provider_concurrency_default(&mut self) {
        let ollama = self.current_default_provider() == "ollama";
        let general = Config::default().limits.max_concurrent_inferences;
        let local = Some(catalog::OLLAMA_MAX_CONCURRENT_INFERENCES as u64);
        let general = general.map(|n| n as u64);

        // `limits[0]` is the concurrency field, built as a `Number` by
        // `limits_fields`, so this is a total match rather than a fallible
        // lookup with an arm nothing can reach.
        let Some(FieldValue::Number(current)) = self.limits.first_mut().map(|f| &mut f.value)
        else {
            return;
        };
        if ollama && *current == general {
            *current = local;
        } else if !ollama && *current == local {
            *current = general;
        }
    }

    /// Commit an edited text buffer into wherever it belongs.
    pub fn commit_edit(&mut self) {
        let Some(edit) = self.edit.take() else {
            return;
        };
        match edit.target {
            EditTarget::Credential(index) => {
                if let Some(row) = self.providers.get_mut(index) {
                    row.value = edit.buffer.trim().to_string();
                    // A typed credential replaces the environment's, and the
                    // row stops claiming the environment supplies it.
                    if !row.value.is_empty() {
                        row.from_env = None;
                    }
                    row.outcome = Outcome::Skipped;
                }
            }
            EditTarget::Field(index) => {
                let Some(fields) = self.fields_mut() else {
                    return;
                };
                if let Some(field) = fields.get_mut(index) {
                    match &mut field.value {
                        FieldValue::Number(n) => {
                            let trimmed = edit.buffer.trim();
                            *n = if trimmed.is_empty() {
                                None
                            } else {
                                trimmed.parse().ok().or(*n)
                            };
                        }
                        // Booleans and choices are never text-edited.
                        FieldValue::Bool(_) | FieldValue::Choice { .. } => {}
                    }
                }
            }
        }
    }

    // ── Producing the plan ──────────────────────────────────────────────────

    /// Fold every choice into the config that will be written.
    pub fn build_config(&self) -> Config {
        let mut config = self.base.clone();

        for row in &self.providers {
            match row.provider.credential {
                Credential::None => {}
                _ if !row.selected => catalog::set_credential(&mut config, row.provider.id, None),
                // An environment-supplied credential is left out of the file:
                // the user put it in their environment on purpose, and
                // `Config::load` already reads it back from there.
                _ if row.value.is_empty() => {
                    catalog::set_credential(&mut config, row.provider.id, None)
                }
                Credential::BaseUrl if row.value == catalog::DEFAULT_OLLAMA_URL => {
                    // Storing the default would pin it; leaving it unset lets
                    // the built-in default (and `$OLLAMA_HOST`) apply.
                    catalog::set_credential(&mut config, row.provider.id, None)
                }
                _ => catalog::set_credential(&mut config, row.provider.id, Some(row.value.clone())),
            }
        }

        // The transport is always in the table, so this reads its row when
        // selected rather than guarding a lookup that cannot miss.
        let transport = self
            .providers
            .iter()
            .find(|r| r.provider.id == "claude-code")
            .filter(|r| r.selected);
        config.providers.claude_code_enabled = transport.is_some();
        if let Some(row) = transport {
            config.providers.claude_code_effort =
                Some(effort_options()[row.effort.min(effort_options().len() - 1)].to_string());
        }

        config.default_provider = self.current_default_provider();
        config.default_model = self
            .current_default_model()
            .filter(|m| m != "(provider default)");
        config.request_timeout_secs = self.current_request_timeout();

        apply_limits_fields(&mut config, &self.limits);

        for row in self.mcp.iter().filter(|r| r.selected) {
            let mut server = row.candidate.config.clone();
            server.name = row.name.clone();
            config.mcp_servers.push(server);
        }

        config
    }

    /// The plan this wizard describes.
    pub fn build_plan(&self) -> SetupPlan {
        SetupPlan {
            config: self.build_config(),
            agents: self
                .agents
                .iter()
                .filter(|r| r.selected)
                .map(|r| r.agent)
                .collect(),
        }
    }

    /// Lines for the review screen.
    pub fn review_lines(&self) -> Vec<String> {
        let plan = self.build_plan();
        let changes = super::plan::changes(&self.base, &plan);
        if changes.is_empty() {
            vec!["Nothing would change.".to_string()]
        } else {
            changes
        }
    }

    /// MCP rows carrying a credential copied verbatim out of another tool's
    /// config, which importing would duplicate into `~/.leviath/config.toml`.
    pub fn selected_inline_secrets(&self) -> Vec<String> {
        self.mcp
            .iter()
            .filter(|r| r.selected && !r.candidate.inline_secrets.is_empty())
            .map(|r| format!("{}: {}", r.name, r.candidate.inline_secrets.join(", ")))
            .collect()
    }
}

/// Reasoning-effort levels for the Claude Code transport, from the provider
/// rather than re-typed here.
pub fn effort_options() -> &'static [&'static str] {
    &leviath_providers::claude_code::EFFORT_LEVELS
}

/// Index of `effort` in [`effort_options`], defaulting to the provider default.
fn effort_index(effort: Option<&str>) -> usize {
    let wanted = effort.unwrap_or(leviath_providers::claude_code::DEFAULT_EFFORT);
    effort_options()
        .iter()
        .position(|e| *e == wanted)
        .unwrap_or_default()
}

/// The Limits screen's fields, seeded from a config.
fn limits_fields(config: &Config) -> Vec<Field> {
    vec![
        Field {
            label: "Max concurrent inferences",
            help: "How many model calls run at once across all agents.",
            value: FieldValue::Number(config.limits.max_concurrent_inferences.map(|n| n as u64)),
        },
        Field {
            label: "Max concurrent tools",
            help: "How many tool calls run at once within one batch.",
            value: FieldValue::Number(Some(config.limits.max_concurrent_tools as u64)),
        },
        Field {
            label: "Default max iterations",
            help: "Per-stage ceiling when a blueprint sets none.",
            value: FieldValue::Number(config.limits.default_max_iterations.map(|n| n as u64)),
        },
        Field {
            label: "Exact token counting",
            help: "Ask the provider for real token counts instead of estimating. Slower.",
            value: FieldValue::Bool(config.limits.exact_token_counting),
        },
        Field {
            label: "Batch tool-call hint",
            help: "Nudge models to request several tools in one turn.",
            value: FieldValue::Bool(config.batch_tool_hint),
        },
    ]
}

/// Write the Limits screen's fields back into a config.
fn apply_limits_fields(config: &mut Config, fields: &[Field]) {
    for (index, field) in fields.iter().enumerate() {
        match (index, &field.value) {
            (0, FieldValue::Number(n)) => {
                config.limits.max_concurrent_inferences = n.map(|n| n as usize)
            }
            // A zero here would deadlock every tool batch, so an explicit unset
            // or 0 falls back to the default rather than being stored.
            (1, FieldValue::Number(n)) => {
                config.limits.max_concurrent_tools = n
                    .filter(|n| *n > 0)
                    .map(|n| n as usize)
                    .unwrap_or(Config::default().limits.max_concurrent_tools)
            }
            (2, FieldValue::Number(n)) => {
                config.limits.default_max_iterations = n.map(|n| n as usize)
            }
            (3, FieldValue::Bool(b)) => config.limits.exact_token_counting = *b,
            (4, FieldValue::Bool(b)) => config.batch_tool_hint = *b,
            _ => {}
        }
    }
}

/// Merge every scan into the flat `(source, candidate)` list the wizard takes,
/// alongside the human-readable errors.
pub fn candidates_from_scans(scans: Vec<import::Scan>) -> (Vec<(String, Candidate)>, Vec<String>) {
    let mut candidates = Vec::new();
    let mut errors = Vec::new();
    for scan in scans {
        match scan.result {
            Ok(found) => candidates.extend(
                found
                    .into_iter()
                    .map(|c| (scan.source.display.to_string(), c)),
            ),
            Err(message) => errors.push(format!("{}: {message}", scan.source.display)),
        }
    }
    (candidates, errors)
}

/// Build an [`MCPServerConfig`] list from selected rows. Exposed for tests and
/// for any future non-terminal front-end.
pub fn selected_servers(rows: &[McpRow]) -> Vec<MCPServerConfig> {
    rows.iter()
        .filter(|r| r.selected)
        .map(|r| {
            let mut server = r.candidate.config.clone();
            server.name = r.name.clone();
            server
        })
        .collect()
}

#[cfg(test)]
pub(super) mod tests {
    use super::*;
    use crate::bundled::BUNDLED_AGENTS;

    /// A wizard over tempdirs and a fixed environment, with a browser opener
    /// that records rather than launches.
    pub(in crate::commands::setup) fn test_wizard(agents_dir: &std::path::Path) -> Wizard {
        Wizard::new(
            Config::default(),
            &|_| None,
            Vec::new(),
            Vec::new(),
            agents_dir,
            std::sync::Arc::new(|_| true),
        )
    }

    fn candidate(name: &str) -> Candidate {
        Candidate {
            config: MCPServerConfig::stdio(name, "npx", vec![]),
            scope: String::new(),
            inline_secrets: Vec::new(),
        }
    }

    // ─── Step ───────────────────────────────────────────────────────────────

    #[test]
    fn every_step_is_titled_and_ordered() {
        for (index, step) in Step::ALL.iter().enumerate() {
            assert!(!step.title().is_empty(), "{step:?} has no title");
            assert_eq!(step.index(), index);
        }
    }

    // ─── construction ───────────────────────────────────────────────────────

    #[test]
    fn a_fresh_install_starts_with_nothing_selected_and_every_agent_queued() {
        let dir = tempfile::tempdir().unwrap();

        let wizard = test_wizard(dir.path());

        assert_eq!(wizard.step, Step::Welcome);
        assert!(wizard.selected_providers().is_empty());
        assert_eq!(wizard.agents.len(), BUNDLED_AGENTS.len());
        assert!(
            wizard.agents.iter().all(|r| r.selected),
            "a fresh install should offer to install everything"
        );
        assert!(
            wizard
                .agents
                .iter()
                .all(|r| r.action == AgentAction::Install)
        );
    }

    #[test]
    fn already_installed_agents_are_listed_but_not_reselected() {
        let dir = tempfile::tempdir().unwrap();
        for agent in BUNDLED_AGENTS {
            crate::bundled::install_bundled(agent, dir.path()).unwrap();
        }

        let wizard = test_wizard(dir.path());

        assert!(
            wizard.agents.iter().all(|r| !r.selected),
            "nothing needs doing, so nothing should be pre-checked"
        );
    }

    #[test]
    fn a_configured_provider_starts_selected_with_its_credential() {
        let dir = tempfile::tempdir().unwrap();
        let base = Config {
            providers: crate::config::ProviderConfig {
                anthropic_api_key: Some("sk-ant-stored".to_string()),
                ..Config::default().providers
            },
            ..Config::default()
        };

        let wizard = Wizard::new(
            base,
            &|_| None,
            Vec::new(),
            Vec::new(),
            dir.path(),
            std::sync::Arc::new(|_| true),
        );

        let row = wizard
            .providers
            .iter()
            .find(|r| r.provider.id == "anthropic")
            .expect("anthropic is in the table");
        assert!(row.selected);
        assert_eq!(row.value, "sk-ant-stored");
        assert!(row.from_env.is_none());
    }

    #[test]
    fn a_key_that_lives_only_in_the_environment_is_shown_and_never_written() {
        // The bug this closes: `Config::load` folds env keys into the struct,
        // so a wizard that re-serializes the whole thing silently writes a key
        // the user deliberately kept in their environment into
        // ~/.leviath/config.toml.
        let dir = tempfile::tempdir().unwrap();

        let wizard = Wizard::new(
            Config::default(),
            &|name| (name == "ANTHROPIC_API_KEY").then(|| "sk-ant-from-env".to_string()),
            Vec::new(),
            Vec::new(),
            dir.path(),
            std::sync::Arc::new(|_| true),
        );

        let row = wizard
            .providers
            .iter()
            .find(|r| r.provider.id == "anthropic")
            .expect("anthropic is in the table");
        assert!(row.selected, "the provider is usable, so it is selected");
        assert_eq!(row.from_env, Some("ANTHROPIC_API_KEY"));
        assert!(row.value.is_empty());

        let written = wizard.build_config();
        assert!(
            written.providers.anthropic_api_key.is_none(),
            "an environment-supplied key must not be copied into the config"
        );
    }

    #[test]
    fn a_stored_key_wins_over_the_environment() {
        // Both present: the file is what setup is editing, so that is what is
        // shown and kept.
        let dir = tempfile::tempdir().unwrap();
        let base = Config {
            providers: crate::config::ProviderConfig {
                anthropic_api_key: Some("sk-ant-stored".to_string()),
                ..Config::default().providers
            },
            ..Config::default()
        };

        let wizard = Wizard::new(
            base,
            &|_| Some("sk-ant-from-env".to_string()),
            Vec::new(),
            Vec::new(),
            dir.path(),
            std::sync::Arc::new(|_| true),
        );

        let row = &wizard.providers[0];
        assert!(row.from_env.is_none());
        assert_eq!(row.value, "sk-ant-stored");
    }

    #[test]
    fn an_empty_environment_variable_does_not_count_as_a_credential() {
        let dir = tempfile::tempdir().unwrap();

        let wizard = Wizard::new(
            Config::default(),
            &|_| Some(String::new()),
            Vec::new(),
            Vec::new(),
            dir.path(),
            std::sync::Arc::new(|_| true),
        );

        assert!(wizard.env_only.is_empty());
        assert!(wizard.selected_providers().is_empty());
    }

    // ─── MCP rows ───────────────────────────────────────────────────────────

    #[test]
    fn an_importable_server_is_preselected_and_named_as_found() {
        let dir = tempfile::tempdir().unwrap();

        let wizard = Wizard::new(
            Config::default(),
            &|_| None,
            vec![("Claude Code".to_string(), candidate("fs"))],
            Vec::new(),
            dir.path(),
            std::sync::Arc::new(|_| true),
        );

        assert_eq!(wizard.mcp.len(), 1);
        assert!(wizard.mcp[0].selected);
        assert!(!wizard.mcp[0].collides);
        assert_eq!(wizard.mcp[0].name, "fs");
        assert_eq!(wizard.mcp[0].source, "Claude Code");
    }

    #[test]
    fn a_server_already_configured_is_offered_unchecked_under_a_free_name() {
        // The user already has it. Silently adding a second copy under a
        // suffixed name is not what "import" means.
        let dir = tempfile::tempdir().unwrap();
        let base = Config {
            mcp_servers: vec![MCPServerConfig::stdio("fs", "npx", vec![])],
            ..Config::default()
        };

        let wizard = Wizard::new(
            base,
            &|_| None,
            vec![("Cursor".to_string(), candidate("fs"))],
            Vec::new(),
            dir.path(),
            std::sync::Arc::new(|_| true),
        );

        assert!(!wizard.mcp[0].selected);
        assert!(wizard.mcp[0].collides);
        assert_eq!(wizard.mcp[0].name, "fs-2");

        // Selecting it anyway stores it under the free name, leaving the
        // original alone.
        let mut wizard = wizard;
        wizard.mcp[0].selected = true;
        let config = wizard.build_config();
        let names: Vec<&str> = config.mcp_servers.iter().map(|s| s.name.as_str()).collect();
        assert_eq!(names, vec!["fs", "fs-2"]);
    }

    #[test]
    fn selected_servers_renames_and_filters() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = Wizard::new(
            Config::default(),
            &|_| None,
            vec![
                ("A".to_string(), candidate("keep")),
                ("B".to_string(), candidate("drop")),
            ],
            Vec::new(),
            dir.path(),
            std::sync::Arc::new(|_| true),
        );
        wizard.mcp[1].selected = false;
        wizard.mcp[0].name = "renamed".to_string();

        let servers = selected_servers(&wizard.mcp);

        assert_eq!(servers.len(), 1);
        assert_eq!(servers[0].name, "renamed");
    }

    #[test]
    fn inline_secrets_are_reported_only_for_selected_rows() {
        let dir = tempfile::tempdir().unwrap();
        let mut secretive = candidate("leaky");
        secretive.inline_secrets = vec!["API_TOKEN".to_string()];

        let mut wizard = Wizard::new(
            Config::default(),
            &|_| None,
            vec![
                ("A".to_string(), secretive),
                ("B".to_string(), candidate("clean")),
            ],
            Vec::new(),
            dir.path(),
            std::sync::Arc::new(|_| true),
        );

        assert_eq!(wizard.selected_inline_secrets(), vec!["leaky: API_TOKEN"]);
        wizard.mcp[0].selected = false;
        assert!(wizard.selected_inline_secrets().is_empty());
    }

    // ─── navigation ─────────────────────────────────────────────────────────

    #[test]
    fn the_cursor_stays_inside_the_current_step() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        wizard.enter(Step::Providers);

        wizard.move_cursor(-5);
        assert_eq!(wizard.cursor, 0);
        wizard.move_cursor(100);
        assert_eq!(wizard.cursor, wizard.providers.len() - 1);
    }

    #[test]
    fn a_step_with_no_rows_pins_the_cursor_at_zero() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        wizard.enter(Step::Welcome);
        wizard.cursor = 4;

        wizard.move_cursor(1);

        assert_eq!(wizard.cursor, 0);
        assert_eq!(wizard.row_count(), 0);
    }

    #[test]
    fn empty_discovery_steps_are_skipped_in_both_directions() {
        // Nobody should have to press Enter through "no MCP servers found" on a
        // clean machine, or through a credentials screen with no providers
        // picked.
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        assert!(wizard.mcp.is_empty());

        wizard.enter(Step::Providers);
        wizard.next_step();
        assert_eq!(wizard.step, Step::Defaults, "credentials screen was empty");

        wizard.enter(Step::Agents);
        wizard.next_step();
        assert_eq!(wizard.step, Step::Review, "MCP screen was empty");

        wizard.prev_step();
        assert_eq!(wizard.step, Step::Agents);
    }

    #[test]
    fn a_nonempty_discovery_step_is_visited() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = Wizard::new(
            Config::default(),
            &|_| None,
            vec![("A".to_string(), candidate("fs"))],
            Vec::new(),
            dir.path(),
            std::sync::Arc::new(|_| true),
        );

        wizard.enter(Step::Agents);
        wizard.next_step();

        assert_eq!(wizard.step, Step::Mcp);
    }

    #[test]
    fn a_scan_error_alone_is_enough_to_show_the_mcp_step() {
        // "We couldn't read your Zed config" is worth a screen even with no
        // servers to import.
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = Wizard::new(
            Config::default(),
            &|_| None,
            Vec::new(),
            vec!["Zed: unreadable".to_string()],
            dir.path(),
            std::sync::Arc::new(|_| true),
        );

        wizard.enter(Step::Agents);
        wizard.next_step();

        assert_eq!(wizard.step, Step::Mcp);
    }

    #[test]
    fn the_first_step_has_nowhere_to_go_back_to() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());

        wizard.prev_step();

        assert_eq!(wizard.step, Step::Welcome);
    }

    #[test]
    fn advancing_past_the_last_step_stays_on_review() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        wizard.enter(Step::Review);

        wizard.next_step();

        assert_eq!(wizard.step, Step::Review);
    }

    #[test]
    fn the_credential_screen_walks_the_selected_providers() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        wizard.providers[0].selected = true;
        wizard.providers[1].selected = true;

        assert_eq!(wizard.detail_row(), Some(0));
        assert!(wizard.next_detail());
        assert_eq!(wizard.detail_row(), Some(1));
        assert!(!wizard.next_detail(), "there is no third provider");
        assert!(wizard.prev_detail());
        assert_eq!(wizard.detail_row(), Some(0));
        assert!(!wizard.prev_detail());
    }

    #[test]
    fn the_credential_screen_has_no_row_when_nothing_is_selected() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        wizard.enter(Step::ProviderDetail);

        assert!(wizard.detail_row().is_none());
        assert_eq!(wizard.row_count(), 0);
    }

    // ─── verification ───────────────────────────────────────────────────────

    #[tokio::test]
    async fn verification_is_requested_for_a_provider_with_a_credential() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        let (mut requests, _replies) = wizard.take_verify_ends().expect("first take");
        wizard.providers[0].selected = true;
        wizard.providers[0].value = "sk-ant-x".to_string();

        wizard.request_verification(0);

        assert!(wizard.providers[0].checking);
        let request = requests.try_recv().expect("a request was queued");
        assert_eq!(request.provider_id, "anthropic");
        assert_eq!(request.creds.api_key.as_deref(), Some("sk-ant-x"));
    }

    #[tokio::test]
    async fn a_blank_api_key_is_not_queued_for_checking() {
        // Failing with "check the key" when none was given says nothing useful.
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        let (mut requests, _replies) = wizard.take_verify_ends().expect("first take");
        wizard.providers[0].selected = true;

        wizard.request_verification(0);

        assert!(!wizard.providers[0].checking);
        assert_eq!(wizard.providers[0].outcome, Outcome::Skipped);
        assert!(requests.try_recv().is_err());
    }

    #[tokio::test]
    async fn an_environment_supplied_key_is_what_gets_checked() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = Wizard::new(
            Config::default(),
            &|name| (name == "ANTHROPIC_API_KEY").then(|| "sk-ant-env".to_string()),
            Vec::new(),
            Vec::new(),
            dir.path(),
            std::sync::Arc::new(|_| true),
        );
        let (mut requests, _replies) = wizard.take_verify_ends().expect("first take");

        wizard.request_verification(0);

        let request = requests.try_recv().expect("a request was queued");
        assert_eq!(request.creds.api_key.as_deref(), Some("sk-ant-env"));
    }

    #[tokio::test]
    async fn ollama_is_checked_by_url_with_no_key() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        let (mut requests, _replies) = wizard.take_verify_ends().expect("first take");
        let index = wizard
            .providers
            .iter()
            .position(|r| r.provider.id == "ollama")
            .expect("ollama is offered");

        wizard.request_verification(index);
        let request = requests.try_recv().expect("a request was queued");
        assert!(request.creds.api_key.is_none());
        assert_eq!(
            request.creds.base_url.as_deref(),
            Some(catalog::DEFAULT_OLLAMA_URL),
            "an empty field means the default endpoint"
        );

        wizard.providers[index].value = "http://box:11434".to_string();
        wizard.request_verification(index);
        let request = requests.try_recv().expect("a second request was queued");
        assert_eq!(request.creds.base_url.as_deref(), Some("http://box:11434"));
    }

    #[tokio::test]
    async fn verify_all_covers_every_selected_provider() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        let (mut requests, _replies) = wizard.take_verify_ends().expect("first take");
        wizard.providers[0].selected = true;
        wizard.providers[0].value = "sk-ant".to_string();
        let ollama = wizard
            .providers
            .iter()
            .position(|r| r.provider.id == "ollama")
            .expect("ollama is offered");
        wizard.providers[ollama].selected = true;

        wizard.verify_all();

        let mut seen = Vec::new();
        while let Ok(request) = requests.try_recv() {
            seen.push(request.provider_id);
        }
        assert_eq!(seen, vec!["anthropic", "ollama"]);
    }

    #[tokio::test]
    async fn an_out_of_range_verification_request_is_a_no_op() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        let (mut requests, _replies) = wizard.take_verify_ends().expect("first take");

        wizard.request_verification(999);

        assert!(requests.try_recv().is_err());
    }

    #[tokio::test]
    async fn replies_land_on_the_right_provider_and_feed_the_model_picker() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        let (_requests, replies) = wizard.take_verify_ends().expect("first take");
        wizard.providers[0].selected = true;
        wizard.providers[0].checking = true;

        replies
            .send(VerifyReply {
                provider_id: "anthropic".to_string(),
                outcome: Outcome::Reachable {
                    models: vec!["claude-opus-5".to_string()],
                },
            })
            .unwrap();
        // A reply for something not in the table is ignored rather than panicking.
        replies
            .send(VerifyReply {
                provider_id: "not-a-provider".to_string(),
                outcome: Outcome::Skipped,
            })
            .unwrap();
        wizard.drain_verifications();

        assert!(!wizard.providers[0].checking);
        assert_eq!(wizard.discovered_models(), vec!["claude-opus-5"]);
    }

    #[tokio::test]
    async fn a_late_reply_refills_the_model_picker() {
        // Moving straight from a credential into Defaults gets there before the
        // check comes back, so the picker was built from an empty model list
        // and stayed that way - caught by driving the real TUI against a live
        // API key.
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        let (_requests, replies) = wizard.take_verify_ends().expect("first take");
        wizard.providers[0].selected = true;
        wizard.enter(Step::Defaults);
        assert_eq!(
            wizard.defaults[1].value.options(),
            ["(provider default)".to_string()],
            "nothing has been reported yet"
        );

        replies
            .send(VerifyReply {
                provider_id: "anthropic".to_string(),
                outcome: Outcome::Reachable {
                    models: vec!["claude-opus-5".to_string()],
                },
            })
            .unwrap();
        wizard.drain_verifications();

        assert!(
            wizard.defaults[1]
                .value
                .options()
                .contains(&"claude-opus-5".to_string()),
            "the picker should have refilled"
        );
    }

    #[tokio::test]
    async fn a_late_reply_does_not_disturb_another_screen() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        let (_requests, replies) = wizard.take_verify_ends().expect("first take");
        wizard.providers[0].selected = true;
        wizard.enter(Step::Limits);
        wizard.limits[0].value = FieldValue::Number(Some(3));

        replies
            .send(VerifyReply {
                provider_id: "anthropic".to_string(),
                outcome: Outcome::Reachable {
                    models: vec!["m".to_string()],
                },
            })
            .unwrap();
        wizard.drain_verifications();

        assert_eq!(wizard.limits[0].value, FieldValue::Number(Some(3)));
    }

    #[test]
    fn the_verification_channel_ends_can_only_be_taken_once() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());

        assert!(wizard.take_verify_ends().is_some());
        assert!(wizard.take_verify_ends().is_none());
    }

    #[test]
    fn models_from_unselected_providers_are_not_offered() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        wizard.providers[0].outcome = Outcome::Reachable {
            models: vec!["hidden".to_string()],
        };

        assert!(wizard.discovered_models().is_empty());
    }

    // ─── forms ──────────────────────────────────────────────────────────────

    #[test]
    fn the_provider_choice_is_a_radio_over_what_was_actually_selected() {
        // A free-text prompt lets a typo through and only fails at the
        // first agent run.
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        let ollama = wizard
            .providers
            .iter()
            .position(|r| r.provider.id == "ollama")
            .expect("ollama is offered");
        wizard.providers[ollama].selected = true;
        wizard.enter(Step::Defaults);

        assert_eq!(wizard.defaults[0].value.options(), ["ollama".to_string()]);
    }

    #[test]
    fn the_provider_choice_falls_back_to_the_configured_one_when_nothing_is_picked() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        wizard.enter(Step::Defaults);

        assert_eq!(
            wizard.defaults[0].value.display(),
            Config::default().default_provider
        );
    }

    #[test]
    fn the_model_picker_is_filled_from_verification_and_keeps_a_stored_value() {
        let dir = tempfile::tempdir().unwrap();
        let base = Config {
            default_model: Some("hand-typed".to_string()),
            ..Config::default()
        };
        let mut wizard = Wizard::new(
            base,
            &|_| None,
            Vec::new(),
            Vec::new(),
            dir.path(),
            std::sync::Arc::new(|_| true),
        );
        wizard.providers[0].selected = true;
        wizard.providers[0].outcome = Outcome::Reachable {
            models: vec!["claude-opus-5".to_string()],
        };

        wizard.enter(Step::Defaults);

        let options = wizard.defaults[1].value.options();
        assert!(options.contains(&"(provider default)".to_string()));
        assert!(options.contains(&"claude-opus-5".to_string()));
        assert_eq!(
            wizard.defaults[1].value.display(),
            "hand-typed",
            "a model already in the config must survive"
        );
    }

    #[test]
    fn only_a_choice_field_has_options() {
        assert_eq!(
            FieldValue::Choice {
                options: vec!["a".into()],
                index: 0
            }
            .options(),
            ["a".to_string()]
        );
        assert!(FieldValue::Number(Some(1)).options().is_empty());
        assert!(FieldValue::Bool(true).options().is_empty());
    }

    #[test]
    fn field_values_read_naturally() {
        assert_eq!(FieldValue::Number(None).display(), "(unset)");
        assert_eq!(FieldValue::Number(Some(7)).display(), "7");
        assert_eq!(FieldValue::Bool(true).display(), "yes");
        assert_eq!(FieldValue::Bool(false).display(), "no");
        assert_eq!(
            FieldValue::Choice {
                options: vec!["a".into()],
                index: 0
            }
            .display(),
            "a"
        );
        assert_eq!(
            FieldValue::Choice {
                options: vec![],
                index: 0
            }
            .display(),
            "(none)"
        );
    }

    #[test]
    fn picking_ollama_drops_the_concurrency_default_to_one() {
        // A local box serves one model at a time; eight concurrent inferences
        // against one Ollama instance queue and thrash rather than going faster.
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        let ollama = wizard
            .providers
            .iter()
            .position(|r| r.provider.id == "ollama")
            .expect("ollama is offered");
        wizard.providers[ollama].selected = true;
        wizard.enter(Step::Defaults);

        wizard.apply_provider_concurrency_default();

        assert_eq!(
            wizard.limits[0].value,
            FieldValue::Number(Some(catalog::OLLAMA_MAX_CONCURRENT_INFERENCES as u64))
        );
    }

    #[test]
    fn ollama_as_the_only_provider_still_lowers_the_concurrency_limit() {
        // Regression: re-picking the default only when an arrow key moves the
        // provider choice misses this case. With Ollama the sole selection it
        // is already at index 0, no arrow is ever pressed, and the limit stays
        // at the hosted-API default of 8 - caught by driving the real TUI.
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        let ollama = wizard
            .providers
            .iter()
            .position(|r| r.provider.id == "ollama")
            .expect("ollama is offered");
        wizard.providers[ollama].selected = true;

        wizard.enter(Step::Defaults);

        assert_eq!(wizard.defaults[0].value.display(), "ollama");
        assert_eq!(
            wizard.build_config().limits.max_concurrent_inferences,
            Some(catalog::OLLAMA_MAX_CONCURRENT_INFERENCES)
        );
    }

    #[test]
    fn switching_back_off_ollama_restores_the_general_default() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        let ollama = wizard
            .providers
            .iter()
            .position(|r| r.provider.id == "ollama")
            .expect("ollama is offered");
        wizard.providers[ollama].selected = true;
        wizard.enter(Step::Defaults);
        wizard.apply_provider_concurrency_default();

        wizard.providers[ollama].selected = false;
        wizard.providers[0].selected = true;
        wizard.rebuild_defaults();
        wizard.apply_provider_concurrency_default();

        assert_eq!(
            wizard.limits[0].value,
            FieldValue::Number(
                Config::default()
                    .limits
                    .max_concurrent_inferences
                    .map(|n| n as u64)
            )
        );
    }

    #[test]
    fn a_hand_typed_concurrency_is_never_overwritten() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        let ollama = wizard
            .providers
            .iter()
            .position(|r| r.provider.id == "ollama")
            .expect("ollama is offered");
        wizard.providers[ollama].selected = true;
        wizard.enter(Step::Defaults);
        wizard.limits[0].value = FieldValue::Number(Some(3));

        wizard.apply_provider_concurrency_default();

        assert_eq!(wizard.limits[0].value, FieldValue::Number(Some(3)));
    }

    // ─── editing ────────────────────────────────────────────────────────────

    #[test]
    fn committing_a_credential_clears_its_stale_verification() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        wizard.providers[0].outcome = Outcome::Reachable {
            models: vec!["m".into()],
        };
        wizard.edit = Some(Edit {
            target: EditTarget::Credential(0),
            buffer: "  sk-ant-new  ".to_string(),
            masked: true,
        });

        wizard.commit_edit();

        assert_eq!(wizard.providers[0].value, "sk-ant-new");
        assert_eq!(
            wizard.providers[0].outcome,
            Outcome::Skipped,
            "the old result was for a different key"
        );
        assert!(wizard.edit.is_none());
    }

    #[test]
    fn typing_a_credential_supersedes_the_environments() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = Wizard::new(
            Config::default(),
            &|_| Some("sk-ant-env".to_string()),
            Vec::new(),
            Vec::new(),
            dir.path(),
            std::sync::Arc::new(|_| true),
        );
        assert!(wizard.providers[0].from_env.is_some());
        wizard.edit = Some(Edit {
            target: EditTarget::Credential(0),
            buffer: "sk-ant-typed".to_string(),
            masked: true,
        });

        wizard.commit_edit();

        assert!(wizard.providers[0].from_env.is_none());
        assert_eq!(
            wizard.build_config().providers.anthropic_api_key.as_deref(),
            Some("sk-ant-typed")
        );
    }

    #[test]
    fn committing_numbers_handles_blank_and_unparseable_input() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        wizard.enter(Step::Limits);

        wizard.edit = Some(Edit {
            target: EditTarget::Field(0),
            buffer: "16".to_string(),
            masked: false,
        });
        wizard.commit_edit();
        assert_eq!(wizard.limits[0].value, FieldValue::Number(Some(16)));

        // Garbage keeps the previous value rather than silently unsetting it.
        wizard.edit = Some(Edit {
            target: EditTarget::Field(0),
            buffer: "not a number".to_string(),
            masked: false,
        });
        wizard.commit_edit();
        assert_eq!(wizard.limits[0].value, FieldValue::Number(Some(16)));

        // Blank means unset, which is a real and different choice.
        wizard.edit = Some(Edit {
            target: EditTarget::Field(0),
            buffer: "   ".to_string(),
            masked: false,
        });
        wizard.commit_edit();
        assert_eq!(wizard.limits[0].value, FieldValue::Number(None));
    }

    #[test]
    fn committing_with_nothing_open_or_out_of_range_is_a_no_op() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        wizard.commit_edit();

        wizard.edit = Some(Edit {
            target: EditTarget::Credential(999),
            buffer: "x".to_string(),
            masked: false,
        });
        wizard.commit_edit();

        wizard.enter(Step::Limits);
        wizard.edit = Some(Edit {
            target: EditTarget::Field(999),
            buffer: "x".to_string(),
            masked: false,
        });
        wizard.commit_edit();

        // A step with no fields at all.
        wizard.enter(Step::Welcome);
        wizard.edit = Some(Edit {
            target: EditTarget::Field(0),
            buffer: "x".to_string(),
            masked: false,
        });
        wizard.commit_edit();

        assert!(wizard.edit.is_none());
    }

    #[test]
    fn every_step_reports_a_sensible_row_count() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = Wizard::new(
            Config::default(),
            &|_| None,
            vec![("A".to_string(), candidate("fs"))],
            Vec::new(),
            dir.path(),
            std::sync::Arc::new(|_| true),
        );
        wizard.providers[0].selected = true;

        for step in Step::ALL {
            wizard.enter(step);
            let rows = wizard.row_count();
            match step {
                Step::Welcome | Step::Review => assert_eq!(rows, 0, "{step:?}"),
                _ => assert!(rows > 0, "{step:?} has no rows"),
            }
            // Fields exist for exactly the two form screens.
            let fields = wizard.fields().len();
            match step {
                Step::Defaults | Step::Limits => assert_eq!(fields, rows, "{step:?}"),
                _ => assert_eq!(fields, 0, "{step:?} should have no fields"),
            }
        }
    }

    #[test]
    fn committing_onto_a_defaults_field_reaches_that_form_too() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        wizard.providers[0].selected = true;
        wizard.enter(Step::Defaults);

        wizard.edit = Some(Edit {
            target: EditTarget::Field(2),
            buffer: "45".to_string(),
            masked: false,
        });
        wizard.commit_edit();

        assert_eq!(wizard.defaults[2].value, FieldValue::Number(Some(45)));
        assert_eq!(wizard.build_config().request_timeout_secs, Some(45));
    }

    #[test]
    fn clearing_a_credential_leaves_the_environment_marker_alone() {
        // Blanking the field is how a user says "use what's in my environment".
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = Wizard::new(
            Config::default(),
            &|_| Some("sk-ant-env".to_string()),
            Vec::new(),
            Vec::new(),
            dir.path(),
            std::sync::Arc::new(|_| true),
        );
        wizard.edit = Some(Edit {
            target: EditTarget::Credential(0),
            buffer: "   ".to_string(),
            masked: true,
        });

        wizard.commit_edit();

        assert!(wizard.providers[0].value.is_empty());
        assert_eq!(wizard.providers[0].from_env, Some("ANTHROPIC_API_KEY"));
    }

    #[test]
    fn a_defaults_form_with_no_choice_field_falls_back_to_the_base_config() {
        // Defensive: a future reorder must not silently drop the setting.
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        wizard.defaults[0].value = FieldValue::Bool(true);

        assert_eq!(
            wizard.build_config().default_provider,
            Config::default().default_provider
        );
    }

    #[test]
    fn an_empty_choice_list_falls_back_to_the_base_config() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        wizard.defaults[0].value = FieldValue::Choice {
            options: Vec::new(),
            index: 0,
        };

        assert_eq!(
            wizard.build_config().default_provider,
            Config::default().default_provider
        );
    }

    #[test]
    fn the_concurrency_default_is_left_alone_when_the_form_is_not_a_number() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        wizard.limits[0].value = FieldValue::Bool(true);

        wizard.apply_provider_concurrency_default();

        assert_eq!(wizard.limits[0].value, FieldValue::Bool(true));
    }

    #[test]
    fn a_text_buffer_committed_onto_a_toggle_leaves_it_alone() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        wizard.enter(Step::Limits);
        let before = wizard.limits[3].value.clone();

        wizard.edit = Some(Edit {
            target: EditTarget::Field(3),
            buffer: "yes".to_string(),
            masked: false,
        });
        wizard.commit_edit();

        assert_eq!(wizard.limits[3].value, before);
    }

    // ─── building the config ────────────────────────────────────────────────

    #[test]
    fn deselecting_a_provider_clears_its_credential() {
        let dir = tempfile::tempdir().unwrap();
        let base = Config {
            providers: crate::config::ProviderConfig {
                anthropic_api_key: Some("sk-ant-stored".to_string()),
                ..Config::default().providers
            },
            ..Config::default()
        };
        let mut wizard = Wizard::new(
            base,
            &|_| None,
            Vec::new(),
            Vec::new(),
            dir.path(),
            std::sync::Arc::new(|_| true),
        );

        wizard.providers[0].selected = false;

        assert!(wizard.build_config().providers.anthropic_api_key.is_none());
    }

    #[test]
    fn ollamas_default_url_is_left_unset_rather_than_pinned() {
        // Storing the default would freeze it and shadow $OLLAMA_HOST.
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        let ollama = wizard
            .providers
            .iter()
            .position(|r| r.provider.id == "ollama")
            .expect("ollama is offered");
        wizard.providers[ollama].selected = true;
        wizard.providers[ollama].value = catalog::DEFAULT_OLLAMA_URL.to_string();

        assert!(wizard.build_config().ollama_base_url.is_none());

        wizard.providers[ollama].value = "http://box:11434".to_string();
        assert_eq!(
            wizard.build_config().ollama_base_url.as_deref(),
            Some("http://box:11434")
        );
    }

    #[test]
    fn the_claude_code_transport_carries_its_effort_only_when_enabled() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        let index = wizard
            .providers
            .iter()
            .position(|r| r.provider.id == "claude-code")
            .expect("the transport is offered");

        assert!(!wizard.build_config().providers.claude_code_enabled);

        wizard.providers[index].selected = true;
        wizard.providers[index].effort = effort_options().len() - 1;
        let config = wizard.build_config();
        assert!(config.providers.claude_code_enabled);
        assert_eq!(
            config.providers.claude_code_effort.as_deref(),
            Some(*effort_options().last().expect("levels exist"))
        );
    }

    #[test]
    fn an_out_of_range_effort_index_clamps_rather_than_panicking() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        let index = wizard
            .providers
            .iter()
            .position(|r| r.provider.id == "claude-code")
            .expect("the transport is offered");
        wizard.providers[index].selected = true;
        wizard.providers[index].effort = 99;

        let config = wizard.build_config();

        assert_eq!(
            config.providers.claude_code_effort.as_deref(),
            Some(*effort_options().last().expect("levels exist"))
        );
    }

    #[test]
    fn the_stored_effort_selects_the_matching_option() {
        let dir = tempfile::tempdir().unwrap();
        let base = Config {
            providers: crate::config::ProviderConfig {
                claude_code_effort: Some("max".to_string()),
                ..Config::default().providers
            },
            ..Config::default()
        };
        let wizard = Wizard::new(
            base,
            &|_| None,
            Vec::new(),
            Vec::new(),
            dir.path(),
            std::sync::Arc::new(|_| true),
        );

        let index = wizard
            .providers
            .iter()
            .position(|r| r.provider.id == "claude-code")
            .expect("the transport is offered");
        assert_eq!(effort_options()[wizard.providers[index].effort], "max");
    }

    #[test]
    fn an_unrecognised_stored_effort_falls_back_to_the_first_level() {
        assert_eq!(effort_index(Some("not-a-level")), 0);
        assert_eq!(
            effort_options()[effort_index(None)],
            leviath_providers::claude_code::DEFAULT_EFFORT
        );
    }

    #[test]
    fn the_provider_default_model_is_stored_as_unset() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        wizard.providers[0].selected = true;
        wizard.enter(Step::Defaults);

        // Index 0 of the model picker is always "(provider default)".
        assert!(wizard.build_config().default_model.is_none());
    }

    #[test]
    fn limits_are_written_back_including_the_zero_guard() {
        // A zero here would deadlock every tool batch, so it falls back to the
        // default rather than being stored.
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        wizard.enter(Step::Limits);
        wizard.limits[0].value = FieldValue::Number(Some(2));
        wizard.limits[1].value = FieldValue::Number(Some(0));
        wizard.limits[2].value = FieldValue::Number(None);
        wizard.limits[3].value = FieldValue::Bool(true);
        wizard.limits[4].value = FieldValue::Bool(false);

        let config = wizard.build_config();

        assert_eq!(config.limits.max_concurrent_inferences, Some(2));
        assert_eq!(
            config.limits.max_concurrent_tools,
            Config::default().limits.max_concurrent_tools
        );
        assert!(config.limits.default_max_iterations.is_none());
        assert!(config.limits.exact_token_counting);
        assert!(!config.batch_tool_hint);
    }

    #[test]
    fn a_field_of_the_wrong_kind_is_ignored_when_writing_limits() {
        // Defensive: nothing builds this shape today, but a future edit that
        // reorders the form must not silently write a boolean into a count.
        let mut config = Config::default();
        apply_limits_fields(
            &mut config,
            &[Field {
                label: "Max concurrent inferences",
                help: "",
                value: FieldValue::Bool(true),
            }],
        );

        assert_eq!(
            config.limits.max_concurrent_inferences,
            Config::default().limits.max_concurrent_inferences
        );
    }

    #[test]
    fn the_plan_carries_only_the_selected_agents() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        for row in wizard.agents.iter_mut().skip(1) {
            row.selected = false;
        }

        let plan = wizard.build_plan();

        assert_eq!(plan.agents.len(), 1);
        assert_eq!(plan.agents[0].name, BUNDLED_AGENTS[0].name);
    }

    #[test]
    fn the_review_says_so_when_nothing_would_change() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        for row in wizard.agents.iter_mut() {
            row.selected = false;
        }

        assert_eq!(wizard.review_lines(), vec!["Nothing would change."]);
    }

    #[test]
    fn the_review_lists_real_changes() {
        let dir = tempfile::tempdir().unwrap();
        let mut wizard = test_wizard(dir.path());
        wizard.providers[0].selected = true;
        wizard.providers[0].value = "sk-ant-x".to_string();

        let lines = wizard.review_lines();

        assert!(lines.iter().any(|l| l.contains("credential set")));
        assert!(lines.iter().any(|l| l.contains("to install")));
    }

    // ─── scan merging ───────────────────────────────────────────────────────

    #[test]
    fn scans_flatten_into_candidates_and_labelled_errors() {
        let scans = vec![
            import::Scan {
                source: import::Source {
                    id: "a",
                    display: "Harness A",
                    path: std::path::PathBuf::from("/a"),
                    layout: import::Layout::ClaudeCode,
                    allows_comments: false,
                },
                result: Ok(vec![candidate("fs")]),
            },
            import::Scan {
                source: import::Source {
                    id: "b",
                    display: "Harness B",
                    path: std::path::PathBuf::from("/b"),
                    layout: import::Layout::CodexToml,
                    allows_comments: false,
                },
                result: Err("unreadable".to_string()),
            },
        ];

        let (candidates, errors) = candidates_from_scans(scans);

        assert_eq!(candidates.len(), 1);
        assert_eq!(candidates[0].0, "Harness A");
        assert_eq!(errors, vec!["Harness B: unreadable"]);
    }
}