//! The edition dataset, vendored and read by hand (ADR-0011).
//!
//! `Problems.csv` is authoritative (ground-game, GROUND-WP-0002 T01). The
//! engine used to invent Problem values and suits; it reads them now.
//!
//! **Why not the `csv` crate.** It fits — 17,651 marginal lines against
//! AM-4b's 19,742 of headroom — and is refused anyway, because that is
//! 89% of everything the budget has left to read 20 rows, and the next
//! dependency would have 2,091 lines to live in. If this data ever grows
//! nested quoting, embedded newlines, or multiple dialects, that decision
//! is wrong and `csv` is the answer (ADR-0011 D1).

use crate::{SolutionCard, Suit};

/// One Problem as the edition prints it.
#[derive(Debug, Clone, Copy, PartialEq, Eq)]
pub struct EditionProblem {
    /// `hidden_priority`: 0 is the Surface Problem.
    pub priority: u8,
    pub value: u8,
    pub suit: Suit,
    /// `visibility == "Surface"` — dealt face up (GR-S01).
    pub surface: bool,
}

/// A Problem's own words. Separate from [`EditionProblem`], which is
/// `Copy` and lives in the aggregate; this is presentation and does not.
///
/// **These columns were in the vendored file all along** and were
/// discarded at parse time (ADR-0015 D1) — the page showed `Repair 2`
/// where the card reads *"Missed Deadline"*. Reading them cost no new
/// bytes and no budget.
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct ProblemText {
    pub priority: u8,
    pub title: String,
    pub problem_text: String,
    pub front_rules: String,
    pub reveal_effect: String,
    pub unresolved_effect: String,
}

/// The text of one scenario's Problems, by `hidden_priority`.
pub fn problem_texts(scenario_id: &str) -> Result<Vec<ProblemText>, String> {
    let t = Table::parse(CSV, "Problems.csv")?;
    let mut out = Vec::new();
    for row in &t.rows {
        if t.get(row, "scenario_id")? != scenario_id {
            continue;
        }
        out.push(ProblemText {
            priority: t
                .get(row, "hidden_priority")?
                .parse()
                .map_err(|_| "hidden_priority is not a number".to_string())?,
            title: t.get(row, "title")?.to_string(),
            problem_text: t.get(row, "problem_text")?.to_string(),
            front_rules: t.get(row, "front_rules")?.to_string(),
            reveal_effect: t.get(row, "reveal_effect")?.to_string(),
            unresolved_effect: t.get(row, "unresolved_effect")?.to_string(),
        });
    }
    if out.is_empty() {
        return Err(format!("no Problem text for {scenario_id}"));
    }
    out.sort_by_key(|p| p.priority);
    Ok(out)
}

const CSV: &str = include_str!("../../../editions/ground-darvo-r0/Problems.csv");
const ACTIONS_CSV: &str = include_str!("../../../editions/ground-darvo-r0/Actions.csv");
const SOLUTIONS_CSV: &str = include_str!("../../../editions/ground-darvo-r0/Solutions.csv");
const MODES_CSV: &str = include_str!("../../../editions/ground-darvo-r0/Modes.csv");
const TOKENS_CSV: &str = include_str!("../../../editions/ground-darvo-r0/Tokens.csv");

/// A vendored CSV, parsed into rows addressable by column name.
///
/// **One reader, four callers** (ADR-0015 D3). The first version was
/// `Problems.csv`-shaped; a per-file copy is how a parser acquires four
/// subtly different bugs.
pub struct Table {
    cols: Vec<String>,
    rows: Vec<Vec<String>>,
}

impl Table {
    fn parse(csv: &str, what: &str) -> Result<Self, String> {
        let mut lines = csv.lines();
        let header = lines.next().ok_or_else(|| format!("{what} is empty"))?;
        let cols: Vec<String> = fields(header)
            .into_iter()
            .map(|c| c.trim_start_matches('\u{feff}').trim().to_string())
            .collect();
        let mut rows = Vec::new();
        for line in lines.filter(|l| !l.trim().is_empty()) {
            let f = fields(line);
            if f.len() != cols.len() {
                return Err(format!(
                    "{what} row has {} fields, header has {}: {line}",
                    f.len(),
                    cols.len()
                ));
            }
            rows.push(f);
        }
        Ok(Self { cols, rows })
    }

    fn at(&self, name: &str) -> Result<usize, String> {
        self.cols
            .iter()
            .position(|c| c == name)
            .ok_or_else(|| format!("edition data has no column {name:?}"))
    }

    /// A named field of one row, trimmed. `Err` names the column, because
    /// a silent empty string is how missing data becomes a blank card.
    fn get<'a>(&'a self, row: &'a [String], name: &str) -> Result<&'a str, String> {
        Ok(row[self.at(name)?].trim())
    }
}

/// What a card says about itself — the game's own words, not ours
/// (ADR-0015 D1/D2, finding F18).
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct CardText {
    pub id: String,
    pub title: String,
    /// The one-line hook. What a player reads first.
    pub tagline: String,
    /// The full text. Shown on demand — five of these at once is a wall.
    pub rules_text: String,
}

fn card_texts(csv: &str, what: &str, id: &str, tag: &str) -> Result<Vec<CardText>, String> {
    let t = Table::parse(csv, what)?;
    let mut out = Vec::new();
    for row in &t.rows {
        out.push(CardText {
            id: t.get(row, id)?.to_string(),
            title: t.get(row, "title")?.to_string(),
            tagline: t.get(row, tag)?.to_string(),
            rules_text: t.get(row, "rules_text")?.to_string(),
        });
    }
    if out.is_empty() {
        return Err(format!("{what} has no rows"));
    }
    Ok(out)
}

/// One component, as the edition prints it (ADR-0016 D1).
///
/// **A token is a view, not a type** (D2): nothing in the aggregate
/// changes shape. This supplies the renderer with the game's own labels
/// and the counts a supply check needs.
#[derive(Debug, Clone, PartialEq, Eq)]
pub struct TokenSpec {
    pub id: String,
    pub name: String,
    /// How many the box holds. **Not a rule** — no numbered rule mentions
    /// a supply, and the engine does not enforce one (D3).
    pub quantity: u32,
    /// `Double` means one physical disc that flips — Freedom (READY /
    /// spent) and Focus/Blame. Two states of one component, not two.
    pub double_sided: bool,
    /// What is printed on it: READY, DENIED, PROTECTION, FOCUS…
    pub front_text: String,
    /// The rule, in the edition's words.
    pub use_text: String,
}

/// Every token the edition ships.
pub fn tokens() -> Result<Vec<TokenSpec>, String> {
    let t = Table::parse(TOKENS_CSV, "Tokens.csv")?;
    let mut out = Vec::new();
    for row in &t.rows {
        out.push(TokenSpec {
            id: t.get(row, "token_id")?.to_string(),
            name: t.get(row, "name")?.to_string(),
            quantity: t
                .get(row, "quantity")?
                .parse()
                .map_err(|_| "quantity is not a number".to_string())?,
            double_sided: t.get(row, "sides")? == "Double",
            front_text: t.get(row, "front_text")?.to_string(),
            use_text: t.get(row, "use")?.to_string(),
        });
    }
    if out.is_empty() {
        return Err("Tokens.csv has no rows".into());
    }
    Ok(out)
}

/// How many of `id` the box holds. `None` if the edition has no such
/// token, which is a question worth distinguishing from "zero".
pub fn supply(id: &str) -> Option<u32> {
    tokens()
        .ok()?
        .into_iter()
        .find(|t| t.id == id)
        .map(|t| t.quantity)
}

/// The five Action cards, in the edition's own words.
pub fn actions() -> Result<Vec<CardText>, String> {
    card_texts(ACTIONS_CSV, "Actions.csv", "action_id", "tagline")
}

/// The Solution cards. `microcopy` is this deck's tagline column.
pub fn solutions() -> Result<Vec<CardText>, String> {
    card_texts(SOLUTIONS_CSV, "Solutions.csv", "solution_id", "microcopy")
}

/// The scoring modes, with the tiebreak the game defines — which T07
/// needs and would otherwise have been invented.
pub fn modes() -> Result<Vec<(CardText, String)>, String> {
    let t = Table::parse(MODES_CSV, "Modes.csv")?;
    let mut out = Vec::new();
    for row in &t.rows {
        out.push((
            CardText {
                id: t.get(row, "mode_id")?.to_string(),
                title: t.get(row, "title")?.to_string(),
                tagline: t.get(row, "tagline")?.to_string(),
                rules_text: t.get(row, "rules_text")?.to_string(),
            },
            t.get(row, "scoring_tiebreak")?.to_string(),
        ));
    }
    Ok(out)
}

/// Split one CSV record, honouring `"…"` quoting.
///
/// `problem_text` contains commas, which is the only reason this is not a
/// `split(',')`. Doubled quotes inside a quoted field are not handled and
/// do not occur; if they ever do, this returns the wrong field count and
/// `problems_of` fails loudly rather than mis-parsing.
fn fields(line: &str) -> Vec<String> {
    let mut out = Vec::new();
    let mut cur = String::new();
    let mut quoted = false;
    for c in line.chars() {
        match c {
            '"' => quoted = !quoted,
            ',' if !quoted => out.push(std::mem::take(&mut cur)),
            c => cur.push(c),
        }
    }
    out.push(cur);
    out
}

fn suit_of(s: &str) -> Option<Suit> {
    match s.trim() {
        "Clarify" => Some(Suit::Clarify),
        "Repair" => Some(Suit::Repair),
        "Boundary" => Some(Suit::Boundary),
        "Change" => Some(Suit::Change),
        _ => None,
    }
}

/// Every Problem of one scenario, ordered by `hidden_priority`.
///
/// Returns `Err` rather than an empty list when the data does not parse:
/// a loader that silently reads nothing would hand `setup` a game with no
/// Problems and look like a rules bug.
pub fn problems_of(scenario_id: &str) -> Result<Vec<EditionProblem>, String> {
    let mut lines = CSV.lines();
    let header = lines.next().ok_or("edition data is empty")?;
    let cols: Vec<String> = fields(header)
        .into_iter()
        .map(|c| c.trim_start_matches('\u{feff}').trim().to_string())
        .collect();
    let at = |name: &str| -> Result<usize, String> {
        cols.iter()
            .position(|c| c == name)
            .ok_or_else(|| format!("edition data has no column {name:?}"))
    };
    let (c_scn, c_pri, c_val, c_sol, c_vis) = (
        at("scenario_id")?,
        at("hidden_priority")?,
        at("point_value")?,
        at("required_solution")?,
        at("visibility")?,
    );

    let mut out = Vec::new();
    for line in lines.filter(|l| !l.trim().is_empty()) {
        let f = fields(line);
        if f.len() != cols.len() {
            return Err(format!(
                "edition row has {} fields, header has {}: {line}",
                f.len(),
                cols.len()
            ));
        }
        if f[c_scn].trim() != scenario_id {
            continue;
        }
        out.push(EditionProblem {
            priority: f[c_pri]
                .trim()
                .parse()
                .map_err(|_| format!("hidden_priority {:?} is not a number", f[c_pri]))?,
            value: f[c_val]
                .trim()
                .parse()
                .map_err(|_| format!("point_value {:?} is not a number", f[c_val]))?,
            suit: suit_of(&f[c_sol])
                .ok_or_else(|| format!("required_solution {:?} is not a suit", f[c_sol]))?,
            surface: f[c_vis].trim() == "Surface",
        });
    }
    if out.is_empty() {
        return Err(format!("edition data has no Problems for {scenario_id}"));
    }
    out.sort_by_key(|p| p.priority);
    Ok(out)
}

/// GR-S01 as ruled by ground-game 2026-08-04: **Surface always, plus
/// hidden priorities `1..=k`**, with k by seat band. Surface is never one
/// of the hidden slots.
///
/// Available points are therefore 6 / 9 / 12 with this edition's values —
/// the numbers ground-game ruled the thresholds 5 / 7 / 9 against.
pub fn hidden_depth(players: u8) -> Result<u8, String> {
    match players {
        2 => Ok(2),
        3..=4 => Ok(3),
        5..=6 => Ok(4),
        other => Err(format!("GR-S01: unsupported player count {other}")),
    }
}

/// The Problems dealt at `players` seats, Surface first.
pub fn deal(scenario_id: &str, players: u8) -> Result<Vec<EditionProblem>, String> {
    let k = hidden_depth(players)?;
    let all = problems_of(scenario_id)?;
    let dealt: Vec<EditionProblem> = all
        .into_iter()
        .filter(|p| p.surface || (p.priority >= 1 && p.priority <= k))
        .collect();
    Ok(dealt)
}

/// The core Solution deck, 6 per suit in canonical order (GR-S04).
pub fn solution_deck() -> Vec<SolutionCard> {
    [Suit::Clarify, Suit::Repair, Suit::Boundary, Suit::Change]
        .into_iter()
        .flat_map(|suit| std::iter::repeat_n(SolutionCard { suit }, 6))
        .collect()
}

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

    /// **The load-bearing control (CB-WP-0028 T02).** The words must come
    /// from the edition, not from a Rust literal beside it.
    ///
    /// Asserted by reading the vendored file directly and requiring the
    /// parsed value to equal what is in it. A test that compared against a
    /// hardcoded expectation would pass for a hand-copied string, which is
    /// exactly the drift this pass exists to end.
    #[test]
    fn the_text_comes_from_the_dataset_not_from_us() {
        let ground = actions()
            .expect("Actions.csv parses")
            .into_iter()
            .find(|c| c.title == "GROUND")
            .expect("the GROUND card is in the edition");

        assert!(
            ACTIONS_CSV.contains(&ground.tagline),
            "the tagline is not a substring of the vendored file — it was invented"
        );
        assert!(
            ACTIONS_CSV.contains(&ground.rules_text),
            "the rules text is not a substring of the vendored file"
        );
        // And it is the card the maintainer could not understand.
        assert_eq!(ground.tagline, "Regulate. Restore the frame. Decide.");
        assert!(
            ground.rules_text.contains("GR—Ground & Restate"),
            "the GROUND card must explain its own modes: {}",
            ground.rules_text
        );
    }

    /// All five Actions, all 24 Solutions, all three Modes — a reader that
    /// returned one row would pass a "the text is real" test.
    #[test]
    fn every_card_in_the_edition_is_read() {
        assert_eq!(actions().expect("actions").len(), 5, "five Action cards");
        assert_eq!(
            solutions().expect("solutions").len(),
            24,
            "24 Solution cards (6 per suit, GR-S04)"
        );
        assert_eq!(modes().expect("modes").len(), 3, "three scoring modes");
    }

    /// A Solution shows its own name, not just its suit — the defect a
    /// player reported as seeing `Clarify` on a card that says otherwise.
    #[test]
    fn a_solution_has_words_of_its_own() {
        let s = solutions().expect("solutions");
        let first = &s[0];
        assert!(!first.title.is_empty() && first.title != "Clarify");
        assert!(
            !first.tagline.is_empty(),
            "microcopy is what makes the card readable"
        );
    }

    /// The mode's tiebreak is the game's, not ours (T07 depends on this).
    #[test]
    fn modes_carry_the_games_own_tiebreak() {
        let m = modes().expect("modes");
        let (coop, tiebreak) = m
            .iter()
            .find(|(c, _)| c.id == "MODE_COOP")
            .expect("MODE_COOP exists");
        assert_eq!(coop.title, "SHARED GROUND");
        assert!(
            !tiebreak.is_empty(),
            "a tiebreak we would otherwise have invented"
        );
    }

    /// ADR-0015 D1: the columns that were in the file all along.
    #[test]
    fn problems_carry_the_text_that_was_already_vendored() {
        let texts = problem_texts("SCN_01").expect("SCN_01 text");
        assert!(!texts.is_empty());
        let surface = &texts[0];
        assert!(
            !surface.title.is_empty() && !surface.problem_text.is_empty(),
            "the Surface Problem must have its own title and text"
        );
        assert!(
            CSV.contains(&surface.title),
            "the title is not from the vendored file"
        );
        // The text list and the dealt list must describe the same Problems.
        let dealt = problems_of("SCN_01").expect("SCN_01 problems");
        assert_eq!(
            texts.len(),
            dealt.len(),
            "text and mechanics disagree about how many Problems SCN_01 has"
        );
    }

    /// ADR-0015 D5 made this visible rather than leaving it a surprise:
    /// the edition ships four scenarios and the engine deals one.
    #[test]
    fn the_edition_ships_more_scenarios_than_the_engine_deals() {
        let mut found = 0;
        for id in ["SCN_01", "SCN_02", "SCN_03", "SCN_04"] {
            if problems_of(id).is_ok() {
                found += 1;
            }
        }
        assert_eq!(
            found, 4,
            "four scenarios are vendored; `setup` hardcodes SCN_01 (ADR-0015 D5)"
        );
    }
}

#[cfg(all(test, feature = "scenarios"))]
mod supply_tests {
    use super::*;

    /// **CB-WP-0029 T03: does play ever exceed what the box holds?**
    ///
    /// Measured over 750 games (2–6 seats, greedy and random): it does
    /// not. This runs a smaller sweep as a standing control, so a future
    /// change that starts minting components fails here instead of being
    /// noticed by a player.
    ///
    /// **A violation is a FINDING, not a bug to fix by adding a bound**
    /// (ADR-0016 D3). No numbered rule mentions a supply; the engine
    /// enforcing one would be inventing a rule, which is CB-WP-0023's
    /// error inverted. If this goes red, the question goes to
    /// `ground-game`: does the box bound the game, or do the rules?
    #[test]
    fn play_never_exceeds_the_components_the_box_holds() {
        use crate::bot::{play, GreedyPolicy, Policy, RandomPolicy};
        use cb_game_runtime::{ScenarioGame, Setup};

        let protection = supply("TOK_PROTECTION").expect("the edition ships Protection");
        let denied = supply("TOK_DENIED").expect("the edition ships Denied");
        let link = supply("TOK_LINK").expect("the edition ships link tokens");

        for players in [2u8, 4, 6] {
            for seed in 0..25u64 {
                let Ok(state) = crate::GroundState::setup(
                    &Setup {
                        players,
                        preset: format!("standard-{players}p"),
                        patch: Default::default(),
                    },
                    seed,
                ) else {
                    continue;
                };
                let mut ps: Vec<Box<dyn Policy>> = (0..players)
                    .map(|i| {
                        if seed % 2 == 0 {
                            Box::new(GreedyPolicy) as Box<dyn Policy>
                        } else {
                            Box::new(RandomPolicy::new(seed ^ u64::from(i))) as Box<dyn Policy>
                        }
                    })
                    .collect();
                let Ok(g) = play(state, &mut ps) else {
                    continue;
                };
                let s = &g.state;

                let on_table: u32 = s.players.values().map(|p| u32::from(p.protection)).sum();
                assert!(
                    on_table <= protection,
                    "{players}p seed {seed}: {on_table} Protection tokens in play, \
                     the box holds {protection}"
                );
                let d = s.problems.values().filter(|q| q.denied).count() as u32;
                assert!(
                    d <= denied,
                    "{d} Denied tokens in play, the box holds {denied}"
                );
                // Two link tokens per relation, one at each endpoint.
                let l = (s.relations.len() * 2) as u32;
                assert!(l <= link, "{l} link tokens in play, the box holds {link}");

                // One double-sided disc per player: it is Focus-side-up
                // somewhere, or Blame-side-up somewhere, never both.
                //
                // The first version of this check compared a seat's own
                // Focus against its OWN blame_from -- but blame_from lists
                // OTHER players' discs, so those are different tokens. It
                // reported conflicts that did not exist.
                for owner in s.players.keys() {
                    let as_focus = s.focus.contains_key(owner);
                    let as_blame = s.players.values().any(|q| q.blame_from.contains(owner));
                    assert!(
                        !(as_focus && as_blame),
                        "{owner:?}'s single Focus/Blame disc is placed twice"
                    );
                }
            }
        }
    }

    /// The supply numbers are the edition's, not ours.
    #[test]
    fn the_supply_comes_from_the_edition() {
        let t = tokens().expect("Tokens.csv parses");
        assert_eq!(t.len(), 9, "the edition ships nine token types");
        assert_eq!(supply("TOK_LINK"), Some(12), "two per player at six seats");
        assert!(
            TOKENS_CSV.contains(&tokens().expect("t")[0].use_text),
            "the rule text is not a substring of the vendored file — it was invented"
        );
        // `sides` must be able to say both, or the flag means nothing.
        assert!(
            t.iter().any(|x| x.double_sided),
            "Freedom and Focus/Blame flip"
        );
        assert!(t.iter().any(|x| !x.double_sided), "most tokens do not");
    }
}