portal/src/build.rs

//! Structure from the plan, words from the model.
//!
//! A `plan.yaml` is a needs spec that also says what each form collects.
//! From it, with no model involved, come `needs.yaml`,
//! `aggregates.yaml`, `site.yaml`, the front door, a followup page per
//! need, a directory per group (gated by `_section.yaml`) holding its
//! desk and the pages only that group may open, and every desk button
//! the state machine allows. What the business said determines all of
//! that; a model has nothing to decide there and much to get wrong
//! (measured: a dropped stage from a strong model, no loadable site at
//! all from a small one).
//!
//! The model writes the words: one small JSON object per page - the
//! question, headings, descriptions, field and button labels - in the
//! plan's language. Words are merged over built-in fallbacks key by
//! key, so a reply that is missing, malformed or partial costs wording,
//! never a working site.

use std::collections::{BTreeMap, BTreeSet};
use std::path::Path;

use anyhow::{anyhow, bail, Context};
use serde::Deserialize;
use serde_json::{json, Map, Value};

use crate::simulate::first_object;

#[derive(Debug, Deserialize)]
#[serde(deny_unknown_fields)]
pub struct Plan {
    pub business: String,
    #[serde(default = "english")]
    pub language: String,
    pub contact: Contact,
    /// What the business does, in its own words - context for the
    /// model's wording, never structure.
    #[serde(default)]
    pub about: String,
    pub needs: Vec<PlanNeed>,
    #[serde(default)]
    pub personas: Vec<Value>,
}

fn english() -> String {
    "en".to_string()
}

#[derive(Debug, Deserialize)]
pub struct Contact {
    pub name: String,
    pub email: String,
}

#[derive(Debug, Deserialize)]
#[serde(deny_unknown_fields)]
pub struct PlanNeed {
    pub id: String,
    pub who: String,
    pub wants: String,
    #[serde(default)]
    pub enters_as: Option<String>,
    pub lands_in: String,
    pub handled_by: String,
    /// Every stage, first to last, finished states included.
    pub stages: Vec<String>,
    pub done_when: Vec<String>,
    #[serde(default)]
    pub success: Vec<String>,
    /// Stages a case may pass over ("awaiting papers" when the papers
    /// were complete).
    #[serde(default)]
    pub skippable: Vec<String>,
    pub collects: Vec<Field>,
    #[serde(default)]
    pub max_fields: Option<usize>,
}

#[derive(Debug, Deserialize, Clone)]
#[serde(deny_unknown_fields)]
pub struct Field {
    pub name: String,
    #[serde(default = "text", rename = "type")]
    pub kind: String,
    #[serde(default)]
    pub optional: bool,
    #[serde(default)]
    pub options: Vec<String>,
}

fn text() -> String {
    "text".to_string()
}

const FIELD_TYPES: &[&str] = &["text", "email", "tel", "textarea", "date", "select"];

fn is_id(s: &str) -> bool {
    !s.is_empty() && s.chars().all(|c| c.is_ascii_lowercase() || c.is_ascii_digit() || c == '_' || c == '-')
}

impl Plan {
    pub fn validate(&self) -> anyhow::Result<()> {
        let mut seen = BTreeSet::new();
        for need in &self.needs {
            let at = |what: &str| format!("need {:?}: {what}", need.id);
            if !is_id(&need.id) || !seen.insert(&need.id) {
                bail!(at("id must be unique ASCII lowercase with - or _"));
            }
            for id in [&need.lands_in, &need.handled_by].into_iter().chain(&need.enters_as).chain(&need.stages) {
                if !is_id(id) {
                    bail!(at(&format!("{id:?} is an identifier and must be ASCII lowercase with - or _")));
                }
            }
            if need.stages.len() < 2 {
                bail!(at("stages needs a first stage and at least one finished one"));
            }
            for state in need.done_when.iter().chain(&need.skippable) {
                if !need.stages.contains(state) {
                    bail!(at(&format!("{state:?} is not one of its stages")));
                }
            }
            for state in &need.success {
                if !need.done_when.contains(state) {
                    bail!(at(&format!("success {state:?} is not one of done_when")));
                }
            }
            if need.done_when.is_empty() || need.done_when.contains(&need.stages[0]) {
                bail!(at("done_when must name finished states, and the first stage cannot be one"));
            }
            for field in &need.collects {
                if !is_id(&field.name) || !FIELD_TYPES.contains(&field.kind.as_str()) {
                    bail!(at(&format!("field {:?}: name must be an identifier and type one of {FIELD_TYPES:?}", field.name)));
                }
                if field.kind == "select" && field.options.is_empty() {
                    bail!(at(&format!("field {:?} is a select and lists no options", field.name)));
                }
            }
        }
        // Needs sharing a bucket share its machine.
        for (bucket, needs) in self.by_bucket() {
            let first = needs[0];
            for other in &needs[1..] {
                if other.stages != first.stages || other.done_when != first.done_when || other.skippable != first.skippable {
                    bail!("needs {:?} and {:?} both land in {bucket:?} and must agree on stages, done_when and skippable", first.id, other.id);
                }
            }
        }
        Ok(())
    }

    fn by_bucket(&self) -> BTreeMap<&str, Vec<&PlanNeed>> {
        let mut map: BTreeMap<&str, Vec<&PlanNeed>> = BTreeMap::new();
        for need in &self.needs {
            map.entry(&need.lands_in).or_default().push(need);
        }
        map
    }
}

/// The moves out of every unfinished stage. The unfinished stages form
/// the line a case walks; from each, the next stage, plus whatever lies
/// beyond a run of skippable ones, plus every finished state that is
/// not a success (a case can be turned down at any point). Success is
/// only reachable from the end of the line.
pub fn machine(need: &PlanNeed) -> BTreeMap<String, Vec<String>> {
    let line: Vec<&String> = need.stages.iter().filter(|s| !need.done_when.contains(s)).collect();
    let ends_well: Vec<&String> = if need.success.is_empty() { need.done_when.iter().collect() } else { need.success.iter().collect() };
    let ends_badly: Vec<&String> = need.done_when.iter().filter(|s| !ends_well.contains(s)).collect();
    let mut moves = BTreeMap::new();
    for (i, stage) in line.iter().enumerate() {
        let mut to: Vec<String> = Vec::new();
        let mut j = i + 1;
        loop {
            match line.get(j) {
                Some(next) => {
                    to.push((*next).clone());
                    if !need.skippable.contains(next) {
                        break;
                    }
                    j += 1;
                }
                None => {
                    to.extend(ends_well.iter().map(|s| (*s).clone()));
                    break;
                }
            }
        }
        to.extend(ends_badly.iter().map(|s| (*s).clone()));
        moves.insert((*stage).clone(), to);
    }
    moves
}

fn humanize(id: &str) -> String {
    let mut words = id.replace(['_', '-'], " ");
    if let Some(first) = words.get_mut(0..1) {
        first.make_ascii_uppercase();
    }
    words
}

fn public_followup(need: &PlanNeed) -> String {
    format!("/received/{}", need.id)
}

fn internal_page(need: &PlanNeed, group: &str) -> String {
    format!("/{group}/{}", need.id)
}

/// The words every page needs, as built-in fallbacks: plain, English,
/// made from the plan's own text. Keyed by file path, then the same
/// JSON shape the model is asked for.
pub fn fallback_words(plan: &Plan) -> BTreeMap<String, Value> {
    let form = |need: &PlanNeed| {
        json!({
            "heading": need.wants,
            "description": format!("For {}.", need.who),
            "button": "Send",
            "form_title": "Details",
            "labels": need.collects.iter().map(|f| (f.name.clone(), Value::String(humanize(&f.name)))).collect::<Map<_, _>>(),
        })
    };
    let mut words = BTreeMap::new();
    let public: Vec<&PlanNeed> = plan.needs.iter().filter(|n| n.enters_as.is_none()).collect();
    words.insert(
        "questions/index.yaml".to_string(),
        json!({
            "question": "What brings you here?",
            "description": plan.about,
            "needs": public.iter().map(|n| (n.id.clone(), form(n))).collect::<Map<_, _>>(),
        }),
    );
    for need in &plan.needs {
        let (path, back) = match &need.enters_as {
            None => (format!("questions/received/{}.yaml", need.id), "/".to_string()),
            Some(group) => (format!("questions/{group}/{}-sent.yaml", need.id), format!("/{group}")),
        };
        let _ = back;
        words.insert(
            path,
            json!({
                "question": "What happens now?",
                "description": format!("It has reached our {}.", humanize(&need.handled_by).to_lowercase()),
                "next_heading": "We read it and come back to you",
                "next_description": format!("Questions in the meantime go to {} at {}.", plan.contact.name, plan.contact.email),
                "back": "Back",
            }),
        );
        if let Some(group) = &need.enters_as {
            let mut page = form(need);
            page["question"] = json!(format!("{}?", humanize(&need.id)));
            page["page_description"] = json!("");
            words.insert(format!("questions/{group}/{}.yaml", need.id), page);
        }
    }
    for group in groups(plan) {
        let buckets: Map<String, Value> = plan
            .by_bucket()
            .into_iter()
            .filter(|(_, needs)| needs.iter().any(|n| n.handled_by == group))
            .map(|(bucket, needs)| {
                let moves: Map<String, Value> = machine(needs[0])
                    .into_iter()
                    .flat_map(|(from, tos)| tos.into_iter().map(move |to| (format!("{from}->{to}"), Value::String(humanize(&to)))))
                    .collect();
                (bucket.to_string(), json!({ "heading": humanize(bucket), "description": "", "moves": moves }))
            })
            .collect();
        let links: Map<String, Value> = plan
            .needs
            .iter()
            .filter(|n| n.enters_as.as_deref() == Some(group.as_str()))
            .map(|n| (n.id.clone(), json!({ "heading": n.wants, "description": "", "button": "Open" })))
            .collect();
        words.insert(
            format!("questions/{group}/index.yaml"),
            json!({ "question": "What needs doing?", "description": "", "confirm": "Confirm", "buckets": buckets, "links": links }),
        );
    }
    words
}

fn groups(plan: &Plan) -> BTreeSet<String> {
    plan.needs.iter().flat_map(|n| [Some(n.handled_by.clone()), n.enters_as.clone()]).flatten().collect()
}

/// Takes the model's strings where it gave them, key by key, and keeps
/// the fallback everywhere else. The shape always comes from the
/// fallback, so a reply can never add, drop or restructure anything.
pub fn merge_words(fallback: &Value, given: &Value) -> Value {
    match (fallback, given) {
        (Value::Object(f), Value::Object(g)) => {
            Value::Object(f.iter().map(|(k, v)| (k.clone(), g.get(k).map_or_else(|| v.clone(), |gv| merge_words(v, gv)))).collect())
        }
        (Value::String(_), Value::String(s)) if !s.trim().is_empty() => Value::String(s.trim().to_string()),
        _ => fallback.clone(),
    }
}

fn s(v: &Value) -> &str {
    v.as_str().unwrap_or_default()
}

fn form_alternative(need: &PlanNeed, w: &Value, action: &str) -> Value {
    json!({
        "name": s(&w["heading"]),
        "description": s(&w["description"]),
        "action": action,
        "consequence": [s(&w["button"])],
        "record_as": need.lands_in,
        "features": [{
            "name": s(&w["form_title"]),
            "requirements": need.collects.iter().map(|f| {
                let mut r = json!({ "name": f.name, "label": s(&w["labels"][&f.name]), "type": f.kind });
                if f.optional { r["optional"] = json!(true); }
                if !f.options.is_empty() { r["options"] = json!(f.options); }
                r
            }).collect::<Vec<_>>(),
        }],
    })
}

/// Every file of the content repo, from the plan and a set of words.
pub fn render(plan: &Plan, words: &BTreeMap<String, Value>) -> anyhow::Result<BTreeMap<String, String>> {
    let mut files: BTreeMap<String, Value> = BTreeMap::new();
    let responsible = json!({ "name": plan.contact.name, "contact": plan.contact.email });

    files.insert("site.yaml".into(), json!({ "title": plan.business, "lang": plan.language }));

    files.insert(
        "aggregates.yaml".into(),
        json!({ "aggregates": plan.by_bucket().into_iter().map(|(bucket, needs)| {
            let need = needs[0];
            let initial = &need.stages[0];
            let first_event = if need.stages.iter().any(|st| st == "received") { "submitted" } else { "received" };
            json!({
                "bucket": bucket,
                "initial": initial,
                "states": need.stages.iter().map(|st| (st.clone(), json!({ "event": if st == initial { first_event } else { st.as_str() } }))).collect::<Map<_, _>>(),
                "transitions": machine(need),
            })
        }).collect::<Vec<_>>() }),
    );

    // The front door: one alternative per need the public may bring.
    let front = &words["questions/index.yaml"];
    let public: Vec<&PlanNeed> = plan.needs.iter().filter(|n| n.enters_as.is_none()).collect();
    files.insert(
        "questions/index.yaml".into(),
        json!({
            "name": s(&front["question"]),
            "description": s(&front["description"]),
            "responsible": responsible,
            "alternatives": public.iter().map(|n| form_alternative(n, &front["needs"][&n.id], &public_followup(n))).collect::<Vec<_>>(),
        }),
    );

    for need in &plan.needs {
        let (path, back) = match &need.enters_as {
            None => (format!("questions/received/{}.yaml", need.id), "/".to_string()),
            Some(group) => (format!("questions/{group}/{}-sent.yaml", need.id), format!("/{group}")),
        };
        let w = &words[&path];
        // Nested and not an index: portal infers a followup page.
        files.insert(
            path,
            json!({
                "name": s(&w["question"]),
                "description": s(&w["description"]),
                "alternatives": [
                    { "name": s(&w["next_heading"]), "description": s(&w["next_description"]) },
                    { "name": s(&w["back"]), "description": "", "action": back, "consequence": [s(&w["back"])] },
                ],
            }),
        );
        if let Some(group) = &need.enters_as {
            let path = format!("questions/{group}/{}.yaml", need.id);
            let w = &words[&path];
            files.insert(
                path,
                json!({
                    // A way in, not an outcome, though it sits in a directory.
                    "followup": false,
                    "name": s(&w["question"]),
                    "description": s(&w["page_description"]),
                    "responsible": responsible,
                    "alternatives": [form_alternative(need, w, &format!("/{group}/{}-sent", need.id))],
                }),
            );
        }
    }

    for group in groups(plan) {
        let w = &words[&format!("questions/{group}/index.yaml")];
        let mut alternatives = Vec::new();
        for (bucket, needs) in plan.by_bucket() {
            if !needs.iter().any(|n| n.handled_by == group) {
                continue;
            }
            let bw = &w["buckets"][bucket];
            alternatives.push(json!({
                "name": s(&bw["heading"]),
                "description": s(&bw["description"]),
                "action": format!("/{group}"),
                "consequence": [s(&w["confirm"])],
                "features": [{ "name": "", "description": "", "resource": {
                    "source": { "kind": "kv", "bucket": bucket },
                    "requires_group": group,
                    "transitions": machine(needs[0]).into_iter().flat_map(|(from, tos)| {
                        tos.into_iter().map(|to| json!({ "from": from, "to": to, "label": s(&bw["moves"][&format!("{from}->{to}")]) })).collect::<Vec<_>>()
                    }).collect::<Vec<_>>(),
                }}],
            }));
        }
        for need in plan.needs.iter().filter(|n| n.enters_as.as_deref() == Some(group.as_str())) {
            let lw = &w["links"][&need.id];
            alternatives.push(json!({
                "name": s(&lw["heading"]),
                "description": s(&lw["description"]),
                "action": internal_page(need, &group),
                "consequence": [s(&lw["button"])],
            }));
        }
        files.insert(format!("questions/{group}/_section.yaml"), json!({ "qualifies": group }));
        files.insert(
            format!("questions/{group}/index.yaml"),
            json!({ "name": s(&w["question"]), "description": s(&w["description"]), "responsible": responsible, "alternatives": alternatives }),
        );
    }

    // The spec the verifier holds the site to. `via` is the heading the
    // words gave that need, filled in mechanically.
    files.insert(
        "needs.yaml".into(),
        json!({
            "needs": plan.needs.iter().map(|n| {
                let (enters, heading) = match &n.enters_as {
                    None => ("/".to_string(), s(&front["needs"][&n.id]["heading"]).to_string()),
                    Some(group) => (internal_page(n, group), s(&words[&format!("questions/{group}/{}.yaml", n.id)]["heading"]).to_string()),
                };
                let required = n.collects.iter().filter(|f| !f.optional).count();
                let mut need = json!({
                    "id": n.id, "who": n.who, "wants": n.wants, "enters": enters, "via": heading,
                    "lands_in": n.lands_in, "handled_by": n.handled_by,
                    "stages": n.stages, "done_when": n.done_when, "success": n.success,
                    "max_steps": 1, "max_fields": n.max_fields.unwrap_or(required),
                });
                if let Some(group) = &n.enters_as { need["enters_as"] = json!(group); }
                need
            }).collect::<Vec<_>>(),
            "personas": plan.personas,
        }),
    );

    files.into_iter().map(|(path, value)| Ok((path, serde_yaml::to_string(&value)?))).collect()
}

fn words_prompt(plan: &Plan, path: &str, fallback: &Value) -> String {
    let purpose = if path == "questions/index.yaml" {
        "the front door: the first page any visitor sees. `question` is the page's one question; under `needs`, each entry is one alternative the visitor can pick, with the form behind it."
    } else if path.ends_with("/index.yaml") {
        "a desk: the page one role inside the business works from. Under `buckets`, each entry is a list of cases; `moves` are the buttons that move a case from one stage to the next (key `from->to`), so label each with what the person has just done. Under `links` are pages this role can open."
    } else if path.contains("/received/") || path.ends_with("-sent.yaml") {
        "a page shown right after someone has sent a form. Say who reads it, when they answer, and what happens next."
    } else {
        "a page only one role inside the business can open, holding one form."
    };
    let context: Vec<String> = plan
        .needs
        .iter()
        .map(|n| format!("- {}: {} - wants: {}. Handled by {}. Stages: {}.", n.id, n.who, n.wants, n.handled_by, n.stages.join(" -> ")))
        .collect();
    format!(
        "You write the words for one page of a website for this business.\n\nBusiness: {}\nAbout: {}\nContact: {} <{}>\nLanguage to write in: {}\n\nEveryone the site serves:\n{}\n\nThe page: {path}\nIt is {purpose}\n\nBelow is the page's wording as JSON, filled with placeholder text. Return the same JSON with every string rewritten. Keep every key exactly as it is; change only the string values.\n\nRules for the words:\n- `question` is a question the reader could ask themselves.\n- A heading says what the reader gets, in the reader's own words, and must work without its description.\n- Lead with what a thing enables. No negations in headings. No trade jargon the reader would not use.\n- Descriptions are one or two short sentences. Labels and buttons are a few words.\n- Write the way people in this trade and country actually speak.\n\n{}\n\nReply with the JSON object only.",
        plan.business,
        plan.about.trim(),
        plan.contact.name,
        plan.contact.email,
        plan.language,
        context.join("\n"),
        serde_json::to_string_pretty(fallback).unwrap_or_default(),
    )
}

pub fn run(argv: &[String]) -> anyhow::Result<()> {
    let value = |flag: &str| argv.iter().position(|a| a == flag).and_then(|i| argv.get(i + 1)).cloned();
    let usage = "usage: portal-trainer build --plan <plan.yaml> --out <dir> [--llm 'cmd'] [--lint question_lint]";
    let plan_path = value("--plan").ok_or_else(|| anyhow!(usage))?;
    let out = std::path::PathBuf::from(value("--out").ok_or_else(|| anyhow!(usage))?);
    let plan: Plan = serde_yaml::from_str(&std::fs::read_to_string(&plan_path).with_context(|| format!("reading {plan_path}"))?)
        .with_context(|| format!("parsing {plan_path}"))?;
    plan.validate()?;

    let mut words = fallback_words(&plan);
    if let Some(cmd) = value("--llm") {
        std::fs::create_dir_all(out.join("llm"))?;
        for (n, (path, fallback)) in words.clone().iter().enumerate() {
            let prompt = words_prompt(&plan, path, fallback);
            let reply = crate::llm_with(&cmd, &prompt, &[("FORMAT", "json"), ("TEMPERATURE", "0.4")]).unwrap_or_default();
            std::fs::write(out.join(format!("llm/{:02}-{}.md", n + 1, path.replace('/', "_"))), format!("{prompt}\n\n=== REPLY ===\n{reply}"))?;
            match first_object(&reply) {
                Some(given) => {
                    words.insert(path.clone(), merge_words(fallback, &given));
                    eprintln!("words: {path}");
                }
                None => eprintln!("words: {path} - no usable reply, keeping the fallback"),
            }
        }
    }
    write_repo(&out, render(&plan, &words)?)?;
    println!("content repo written to {}", out.display());

    if let Some(lint) = value("--lint") {
        let output = std::process::Command::new(&lint).arg("--path").arg(out.join("questions")).output().with_context(|| format!("running {lint}"))?;
        print!("{}{}", String::from_utf8_lossy(&output.stdout), String::from_utf8_lossy(&output.stderr));
        if !output.status.success() {
            bail!("the verifier rejected a deterministically built site - that is a bug in the builder, not in the words");
        }
    }
    Ok(())
}

fn write_repo(out: &Path, files: BTreeMap<String, String>) -> anyhow::Result<()> {
    // The questions tree is rebuilt whole, so a page from an earlier
    // plan never lingers.
    let _ = std::fs::remove_dir_all(out.join("questions"));
    for (path, body) in files {
        let target = out.join(&path);
        if let Some(parent) = target.parent() {
            std::fs::create_dir_all(parent)?;
        }
        std::fs::write(target, body)?;
    }
    Ok(())
}

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

    fn need(stages: &[&str], done: &[&str], success: &[&str], skippable: &[&str]) -> PlanNeed {
        let v = |xs: &[&str]| xs.iter().map(|x| x.to_string()).collect::<Vec<_>>();
        PlanNeed {
            id: "n".into(), who: "w".into(), wants: "x".into(), enters_as: None,
            lands_in: "b".into(), handled_by: "g".into(),
            stages: v(stages), done_when: v(done), success: v(success), skippable: v(skippable),
            collects: vec![], max_fields: None,
        }
    }

    #[test]
    fn the_machine_walks_the_line_and_can_be_turned_down_anywhere() {
        let m = machine(&need(&["open", "surveyed", "quoted", "won", "lost"], &["won", "lost"], &["won"], &[]));
        assert_eq!(m["open"], ["surveyed", "lost"]);
        assert_eq!(m["surveyed"], ["quoted", "lost"]);
        assert_eq!(m["quoted"], ["won", "lost"]);
        assert!(!m.contains_key("won"));
    }

    #[test]
    fn a_skippable_stage_can_be_passed_over() {
        let m = machine(&need(&["open", "awaiting_papers", "approved", "declined"], &["approved", "declined"], &["approved"], &["awaiting_papers"]));
        assert_eq!(m["open"], ["awaiting_papers", "approved", "declined"]);
        assert_eq!(m["awaiting_papers"], ["approved", "declined"]);
    }

    #[test]
    fn a_line_with_one_ending_has_no_way_to_be_turned_down() {
        let m = machine(&need(&["open", "in_hand", "closed"], &["closed"], &["closed"], &[]));
        assert_eq!(m["open"], ["in_hand"]);
        assert_eq!(m["in_hand"], ["closed"]);
    }

    #[test]
    fn words_take_the_models_strings_and_never_its_structure() {
        let fallback = json!({"question": "What?", "needs": {"a": {"heading": "A", "labels": {"email": "Email"}}}});
        let given = json!({"question": "  Hva trenger du?  ", "needs": {"a": {"heading": "", "labels": {"email": 7, "extra": "x"}}, "b": {"heading": "B"}}, "injected": "y"});
        let merged = merge_words(&fallback, &given);
        assert_eq!(merged, json!({"question": "Hva trenger du?", "needs": {"a": {"heading": "A", "labels": {"email": "Email"}}}}));
    }

    const PLAN: &str = "business: Nordvik Bygg\ncontact: { name: Ingrid, email: i@n.example }\nabout: We fix old buildings.\nneeds:\n  - id: survey\n    who: owners\n    wants: Someone to look at the building\n    lands_in: enquiries\n    handled_by: project_managers\n    stages: [open, surveyed, quoted, won, lost]\n    done_when: [won, lost]\n    success: [won]\n    collects:\n      - { name: email, type: email }\n      - { name: problem, type: textarea }\n      - { name: address, optional: true }\n  - id: report\n    who: crew\n    wants: Report a hazard\n    enters_as: crew\n    lands_in: site_issues\n    handled_by: hse\n    stages: [open, in_hand, closed]\n    done_when: [closed]\n    success: [closed]\n    collects:\n      - { name: kind, type: select, options: [Hazard, Near miss] }\n";

    #[test]
    fn a_plan_renders_every_file_the_site_needs() {
        let plan: Plan = serde_yaml::from_str(PLAN).unwrap();
        plan.validate().unwrap();
        let files = render(&plan, &fallback_words(&plan)).unwrap();
        let paths: Vec<&str> = files.keys().map(String::as_str).collect();
        assert_eq!(paths, [
            "aggregates.yaml", "needs.yaml",
            "questions/crew/_section.yaml", "questions/crew/index.yaml", "questions/crew/report-sent.yaml", "questions/crew/report.yaml",
            "questions/hse/_section.yaml", "questions/hse/index.yaml",
            "questions/index.yaml",
            "questions/project_managers/_section.yaml", "questions/project_managers/index.yaml",
            "questions/received/survey.yaml", "site.yaml",
        ]);
        // The crew's form is gated, a way in, and recorded for the safety officer's desk.
        assert!(files["questions/crew/_section.yaml"].contains("qualifies: crew"));
        assert!(files["questions/crew/report.yaml"].contains("followup: false"));
        assert!(files["questions/hse/index.yaml"].contains("bucket: site_issues"));
        assert!(files["questions/hse/index.yaml"].contains("to: closed"));
        // The spec names the heading the words gave, and the budget the form implies.
        assert!(files["needs.yaml"].contains("via: Someone to look at the building"));
        assert!(files["needs.yaml"].contains("max_fields: 2"));
        assert!(files["needs.yaml"].contains("enters: /crew/report"));
    }

    #[test]
    fn a_plan_with_a_bad_identifier_or_a_disagreeing_bucket_is_refused() {
        let bad: Plan = serde_yaml::from_str(&PLAN.replace("lost]", "avslått]")).unwrap();
        assert!(bad.validate().unwrap_err().to_string().contains("ASCII"));
        let clash = format!("{PLAN}  - id: other\n    who: w\n    wants: x\n    lands_in: enquiries\n    handled_by: project_managers\n    stages: [open, won]\n    done_when: [won]\n    collects: []\n");
        let plan: Plan = serde_yaml::from_str(&clash).unwrap();
        assert!(plan.validate().unwrap_err().to_string().contains("must agree"));
    }
}