ling-lang 2030.1.22

// src/astviz.rs — project-wide AST → SVG in three styles.
//
// A whole Ling project is treated as one program (all `.ling` files merged) while
// preserving each definition's *file scope*. Three renderings are produced:
//
//   • Technical — colour-coded function cards with geometric call icons, grouped
//     into per-file bands, with caller→callee graph edges.
//   • Artwork   — text-free, esoteric composition of translucent stars/polygons
//     (3–8 sides) clustered per file; a cubist sigil of the program's shape.
//   • Ling      — Ling-centric tiles: named, colour-coded, laid out per file with
//     balance and harmony in mind.
//
// Every SVG auto-fits its content (tight viewBox) and declares a 300-DPI physical
// size so raster exports are crisp. Output is written to ./AST/ by `ling ast`.

use std::collections::HashSet;
use std::fmt::Write;
use crate::parser::ast::*;
use crate::visualize::{Cat, categorize, icon, is_vtex, is_audio};

// ── Public API ──────────────────────────────────────────────────────────────

#[derive(Clone, Copy, PartialEq, Eq)]
pub enum AstStyle { Technical, Artwork, Ling }

impl AstStyle {
    pub fn slug(self) -> &'static str {
        match self { AstStyle::Technical => "technical", AstStyle::Artwork => "artwork", AstStyle::Ling => "ling" }
    }
}

/// Render the merged project (a list of `(file_label, Program)`) in `style`.
pub fn render(style: AstStyle, project: &str, files: &[(String, Program)]) -> String {
    let model = Project::analyze(project, files);
    match style {
        AstStyle::Technical => render_technical(&model),
        AstStyle::Artwork   => render_artwork(&model),
        AstStyle::Ling      => render_ling(&model),
    }
}

// ── Analysed model (file scope preserved) ────────────────────────────────────

struct Call { name: String, cat: Cat, count: usize }

struct Func {
    name: String,
    params: Vec<String>,
    calls: Vec<Call>,
    has_loop: bool,
    is_entry: bool,
    vtex: usize,
    audio: usize,
}

struct FileScope {
    label: String,
    funcs: Vec<Func>,
    globals: Vec<(String, String)>,
    uses: Vec<String>,
}

struct Project {
    name: String,
    files: Vec<FileScope>,
    fn_names: HashSet<String>,
}

const ENTRY_NAMES: &[&str] = &[
    "start", "main", "启", "เริ่ม", "시작", "始め", "始", "начать", "начало",
    "inicio", "comenzar", "début", "commencer", "anfang", "starten", "início",
];
fn is_entry(name: &str) -> bool { ENTRY_NAMES.contains(&name) }

impl Project {
    fn analyze(name: &str, files: &[(String, Program)]) -> Self {
        // First pass: every function/entry name across the whole project (for edges).
        let mut fn_names = HashSet::new();
        for (_, prog) in files {
            collect_names(&prog.items, &mut fn_names);
        }

        let mut scopes = Vec::new();
        for (label, prog) in files {
            let mut funcs = Vec::new();
            let mut globals = Vec::new();
            let mut uses = Vec::new();
            collect_scope(&prog.items, "", &mut funcs, &mut globals, &mut uses);
            // Skip empty files so the canvas stays meaningful.
            if funcs.is_empty() && globals.is_empty() && uses.is_empty() { continue; }
            scopes.push(FileScope {
                label: short_label(label),
                funcs, globals, uses,
            });
        }
        Project { name: name.to_string(), files: scopes, fn_names }
    }

    fn total_funcs(&self) -> usize { self.files.iter().map(|f| f.funcs.len()).sum() }
}

fn short_label(path: &str) -> String {
    let p = path.replace('\\', "/");
    p.rsplit('/').next().unwrap_or(&p).to_string()
}

fn collect_names(items: &[Item], out: &mut HashSet<String>) {
    for it in items {
        match it {
            Item::Fn(f) => { out.insert(f.name.clone()); }
            Item::Bind(name, Expr::Do(_)) => { out.insert(name.clone()); }
            Item::Mod(_, body) => collect_names(body, out),
            _ => {}
        }
    }
}

fn collect_scope(items: &[Item], ns: &str, funcs: &mut Vec<Func>,
                 globals: &mut Vec<(String, String)>, uses: &mut Vec<String>) {
    let q = |n: &str| if ns.is_empty() { n.to_string() } else { format!("{ns}::{n}") };
    for it in items {
        match it {
            Item::Fn(f) => funcs.push(build_func(q(&f.name), f.params.clone(), &f.body, is_entry(&f.name))),
            Item::Bind(name, Expr::Do(body)) => {
                funcs.push(build_func(q(name), vec![], body, is_entry(name)));
            }
            Item::Bind(name, expr) => globals.push((q(name), value_repr(expr))),
            Item::Mod(name, body) => collect_scope(body, &q(name), funcs, globals, uses),
            Item::Use { path, alias } => {
                let a = alias.as_deref().map(|x| format!(" as {x}")).unwrap_or_default();
                uses.push(format!("{path}{a}"));
            }
            Item::TypeAlias(n, t) => globals.push((q(n), format!("type {t}"))),
        }
    }
}

fn value_repr(e: &Expr) -> String {
    match e {
        Expr::Number(n) => if n.fract() == 0.0 { format!("{}", *n as i64) } else { format!("{n:.2}") },
        Expr::Str(_)    => "\"…\"".into(),
        Expr::Bool(b)   => format!("{b}"),
        Expr::Array(_)  => "[…]".into(),
        _               => "…".into(),
    }
}

fn build_func(name: String, params: Vec<String>, body: &[Stmt], is_entry: bool) -> Func {
    let mut raw = Vec::new();
    let mut has_loop = false;
    walk_stmts(body, &mut raw, &mut has_loop);
    let calls = aggregate(raw);
    let vtex  = calls.iter().filter(|c| is_vtex(c.cat)).map(|c| c.count).sum();
    let audio = calls.iter().filter(|c| is_audio(c.cat)).map(|c| c.count).sum();
    Func { name, params, calls, has_loop, is_entry, vtex, audio }
}

fn aggregate(raw: Vec<(String, Cat)>) -> Vec<Call> {
    let mut out: Vec<Call> = Vec::new();
    for (name, cat) in raw {
        if let Some(l) = out.last_mut() { if l.name == name { l.count += 1; continue; } }
        out.push(Call { name, cat, count: 1 });
    }
    out
}

// ── AST walking (thorough: catches calls in every expression position) ────────

fn walk_stmts(stmts: &[Stmt], out: &mut Vec<(String, Cat)>, lp: &mut bool) {
    for s in stmts {
        match s { Stmt::Expr(e) | Stmt::Return(e) | Stmt::Bind(_, e) => walk_expr(e, out, lp) }
    }
}

fn walk_expr(e: &Expr, out: &mut Vec<(String, Cat)>, lp: &mut bool) {
    match e {
        Expr::Call(func, args) => {
            let name = match func.as_ref() {
                Expr::Ident(n) => Some(n.clone()),
                Expr::Path(segs) => segs.last().cloned(),
                _ => { walk_expr(func, out, lp); None }
            };
            if let Some(n) = name { let cat = categorize(&n); out.push((n, cat)); }
            for a in args { walk_expr(a, out, lp); }
        }
        Expr::MethodCall { receiver, method, args } => {
            walk_expr(receiver, out, lp);
            out.push((method.clone(), categorize(method)));
            for a in args { walk_expr(a, out, lp); }
        }
        Expr::While { cond, body } => { *lp = true; walk_expr(cond, out, lp); walk_stmts(body, out, lp); }
        Expr::For { iter, body, .. } => { *lp = true; walk_expr(iter, out, lp); walk_stmts(body, out, lp); }
        Expr::Do(ss) => walk_stmts(ss, out, lp),
        Expr::If { cond, then, elseifs, else_body } => {
            walk_expr(cond, out, lp);
            walk_stmts(then, out, lp);
            for (c, b) in elseifs { walk_expr(c, out, lp); walk_stmts(b, out, lp); }
            if let Some(b) = else_body { walk_stmts(b, out, lp); }
        }
        Expr::Match(scrut, arms) => {
            walk_expr(scrut, out, lp);
            for a in arms { walk_expr(&a.body, out, lp); }
        }
        Expr::BinOp(_, a, b) | Expr::Range(a, b) | Expr::Index(a, b) => {
            walk_expr(a, out, lp); walk_expr(b, out, lp);
        }
        Expr::Ref(x) | Expr::Await(x) => walk_expr(x, out, lp),
        Expr::Closure(_, body) => walk_expr(body, out, lp),
        Expr::Array(es) => for a in es { walk_expr(a, out, lp); },
        _ => {}
    }
}

// ── Shared SVG helpers ────────────────────────────────────────────────────────

fn esc(s: &str) -> String { s.replace('&', "&amp;").replace('<', "&lt;").replace('>', "&gt;") }
fn f(v: f32) -> String { format!("{v:.2}") }

/// Wrap a body in an auto-fit, 300-DPI SVG document. `w`/`h` are the content
/// extents in user units (px); physical size is `w/300 × h/300` inches.
fn svg_doc(w: f32, h: f32, bg_body: &str, body: &str) -> String {
    format!(
        r##"<?xml version="1.0" encoding="UTF-8"?>
<svg xmlns="http://www.w3.org/2000/svg" width="{win:.3}in" height="{hin:.3}in" viewBox="0 0 {w} {h}" preserveAspectRatio="xMidYMid meet" style="font-family:'JetBrains Mono','Fira Code',monospace,sans-serif">
{bg_body}{body}
</svg>"##,
        win = w / 300.0, hin = h / 300.0, w = f(w), h = f(h),
    )
}

/// Star polygon points: `sides` points alternating outer/inner radius.
fn star_points(cx: f32, cy: f32, ro: f32, ri: f32, sides: usize, rot: f32) -> String {
    let n = sides.max(2);
    (0..n * 2).map(|i| {
        let a = rot + i as f32 * std::f32::consts::PI / n as f32;
        let r = if i % 2 == 0 { ro } else { ri };
        format!("{},{}", f(cx + r * a.cos()), f(cy + r * a.sin()))
    }).collect::<Vec<_>>().join(" ")
}

/// Regular polygon points.
fn ngon_points(cx: f32, cy: f32, r: f32, sides: usize, rot: f32) -> String {
    let n = sides.max(3);
    (0..n).map(|i| {
        let a = rot - std::f32::consts::FRAC_PI_2 + i as f32 * std::f32::consts::TAU / n as f32;
        format!("{},{}", f(cx + r * a.cos()), f(cy + r * a.sin()))
    }).collect::<Vec<_>>().join(" ")
}

/// Tiny deterministic hash → used for reproducible "random" placement.
fn hash(s: &str) -> u64 {
    let mut h = 1469598103934665603u64;
    for b in s.bytes() { h ^= b as u64; h = h.wrapping_mul(1099511628211); }
    h
}
fn frand(seed: u64, i: u64) -> f32 {
    let mut x = seed ^ i.wrapping_mul(0x9E3779B97F4A7C15);
    x ^= x >> 30; x = x.wrapping_mul(0xBF58476D1CE4E5B9);
    x ^= x >> 27; x = x.wrapping_mul(0x94D049BB133111EB);
    x ^= x >> 31;
    (x as f64 / u64::MAX as f64) as f32
}

/// Sides (3..=8) chosen deterministically from a call category + name.
fn shape_sides(cat: Cat, name: &str) -> usize {
    let base = match cat {
        Cat::Star | Cat::Yantra => 5,
        Cat::Flower | Cat::Chakra => 6,
        Cat::Lotus => 8,
        Cat::Present => 3,
        Cat::Fill | Cat::Grid => 4,
        Cat::Rain => 7,
        _ => 0,
    };
    if base != 0 { base } else { 3 + (hash(name) % 6) as usize }
}

// ── Background ────────────────────────────────────────────────────────────────

const BG: &str = "#0b0b1a";

fn bg_rect(w: f32, h: f32, fill: &str) -> String {
    format!(r##"<rect x="0" y="0" width="{}" height="{}" fill="{}"/>"##, f(w), f(h), fill)
}

// ══════════════════════════════════════════════════════════════════════════════
// 1. TECHNICAL — file-banded function cards + call icons + graph edges
// ══════════════════════════════════════════════════════════════════════════════

const T_MARGIN: f32 = 36.0;
const T_TITLE_H: f32 = 96.0;
const T_CARD_W: f32 = 360.0;
const T_CARD_GAP: f32 = 16.0;
const T_COLS: usize = 3;
const T_FILE_HDR: f32 = 40.0;
const T_ICON: f32 = 24.0;
const T_ICONS_ROW: usize = 10;

fn t_card_h(fc: &Func) -> f32 {
    let rows = (fc.calls.len() + T_ICONS_ROW - 1).max(1) / T_ICONS_ROW + 1;
    24.0 * 2.0 + 30.0 + 18.0 + rows as f32 * (T_ICON + 5.0) + 6.0
}

fn render_technical(p: &Project) -> String {
    let content_w = T_COLS as f32 * (T_CARD_W + T_CARD_GAP) - T_CARD_GAP;
    let w = content_w + T_MARGIN * 2.0;

    // Layout pass: per file, pack cards into T_COLS shortest-column order.
    // Records (function-name → card-centre) for edges.
    struct Placed<'a> { fc: &'a Func, x: f32, y: f32, h: f32 }
    let mut placed: Vec<Placed> = Vec::new();
    let mut centers: std::collections::HashMap<String, (f32, f32)> = std::collections::HashMap::new();
    let mut file_bands: Vec<(String, usize, f32, f32)> = Vec::new(); // (label, n_glob, y, height)

    let mut y = T_TITLE_H + 10.0;
    for fs in &p.files {
        let band_top = y;
        y += T_FILE_HDR;
        let mut col_y = [y; T_COLS];
        for fc in &fs.funcs {
            let h = t_card_h(fc);
            let (col, cy) = col_y.iter().enumerate()
                .min_by(|a, b| a.1.partial_cmp(b.1).unwrap()).map(|(i, &v)| (i, v)).unwrap();
            let x = T_MARGIN + col as f32 * (T_CARD_W + T_CARD_GAP);
            centers.insert(fc.name.clone(), (x + T_CARD_W / 2.0, cy + h / 2.0));
            placed.push(Placed { fc, x, y: cy, h });
            col_y[col] = cy + h + T_CARD_GAP;
        }
        let band_bottom = col_y.iter().cloned().fold(y, f32::max);
        // Reserve room for globals/uses summary under the band.
        let extra = if fs.globals.is_empty() && fs.uses.is_empty() { 0.0 } else { 26.0 };
        file_bands.push((fs.label.clone(), fs.globals.len() + fs.uses.len(), band_top, band_bottom - band_top + extra));
        y = band_bottom + extra + 24.0;
    }
    let h = y + T_MARGIN;

    let mut body = String::new();
    body.push_str(DEFS_T);

    // Subtle grid overlay
    let _ = write!(body, r##"<rect width="{}" height="{}" fill="url(#tgrid)" opacity="0.06"/>"##, f(w), f(h));

    // Title
    let tf = p.total_funcs();
    let nfiles = p.files.len();
    let _ = write!(body,
        r##"<text x="{}" y="44" fill="#ffd700" font-size="11" font-weight="bold" letter-spacing="3" opacity="0.7">LING · AST · TECHNICAL</text>
            <text x="{}" y="78" fill="#d8d8ff" font-size="30" font-weight="bold">{}</text>
            <text x="{}" y="78" fill="#52528a" font-size="13" text-anchor="end">{} files · {} fns</text>"##,
        f(T_MARGIN), f(T_MARGIN), esc(&p.name), f(w - T_MARGIN), nfiles, tf);

    // Graph edges (behind cards): caller centre → callee centre, faint curves.
    for pl in &placed {
        let (x0, y0) = *centers.get(&pl.fc.name).unwrap();
        for c in &pl.fc.calls {
            if !p.fn_names.contains(&c.name) { continue; }
            if let Some(&(x1, y1)) = centers.get(&c.name) {
                if (x0 - x1).abs() < 0.5 && (y0 - y1).abs() < 0.5 { continue; }
                let mx = (x0 + x1) / 2.0;
                let _ = write!(body,
                    r##"<path d="M {},{} C {},{} {},{} {},{}" fill="none" stroke="{}" stroke-width="1.1" opacity="0.22"/>"##,
                    f(x0), f(y0), f(mx), f(y0), f(mx), f(y1), f(x1), f(y1), c.cat.color());
            }
        }
    }

    // File band frames + headers
    for (label, _n, by, bh) in &file_bands {
        let _ = write!(body,
            r##"<rect x="{}" y="{}" width="{}" height="{}" rx="12" fill="#10102a" opacity="0.45" stroke="#22225a" stroke-width="1"/>
                <text x="{}" y="{}" fill="#8be9fd" font-size="14" font-weight="bold">◈ {}</text>"##,
            f(T_MARGIN - 12.0), f(*by), f(content_w + 24.0), f(*bh),
            f(T_MARGIN), f(by + 26.0), esc(label));
    }

    // Cards
    for pl in &placed { body.push_str(&t_card(pl.fc, pl.x, pl.y, pl.h)); }

    // Per-file globals/uses footnote
    for (fs, (_, _, by, bh)) in p.files.iter().zip(file_bands.iter()) {
        if fs.globals.is_empty() && fs.uses.is_empty() { continue; }
        let fy = by + bh - 8.0;
        let mut parts: Vec<String> = fs.globals.iter().map(|(n, v)| format!("◇ {n}={v}")).collect();
        parts.extend(fs.uses.iter().map(|u| format!("use {u}")));
        let _ = write!(body,
            r##"<text x="{}" y="{}" fill="#52528a" font-size="10">{}</text>"##,
            f(T_MARGIN), f(fy), esc(&parts.join("    ")));
    }

    svg_doc(w, h, &bg_rect(w, h, BG), &body)
}

const DEFS_T: &str = r##"<defs>
  <filter id="glow-g" x="-30%" y="-30%" width="160%" height="160%"><feGaussianBlur in="SourceGraphic" stdDeviation="3" result="b"/><feMerge><feMergeNode in="b"/><feMergeNode in="SourceGraphic"/></feMerge></filter>
  <pattern id="tgrid" width="40" height="40" patternUnits="userSpaceOnUse"><path d="M 40 0 L 0 0 0 40" fill="none" stroke="#ffffff" stroke-width="0.4"/></pattern>
</defs>"##;

fn t_card(fc: &Func, x: f32, y: f32, h: f32) -> String {
    let dominant = fc.calls.iter().max_by_key(|c| c.count).map(|c| c.cat.color()).unwrap_or("#6ab0f5");
    let border = if fc.is_entry { "#ffd700" } else { dominant };
    let bw = if fc.is_entry { 2.5 } else { 1.2 };
    let glow = if fc.is_entry { r##" filter="url(#glow-g)""## } else { "" };
    let mut s = String::new();
    let _ = write!(s,
        r##"<rect x="{}" y="{}" width="{}" height="{}" rx="8" fill="#13132e" stroke="{}" stroke-width="{}"{}/>
           <rect x="{}" y="{}" width="4" height="{}" rx="2" fill="{}" opacity="0.7"/>"##,
        f(x), f(y), f(T_CARD_W), f(h), border, bw, glow,
        f(x + 2.0), f(y + 2.0), f(h - 4.0), border);

    let name_y = y + 26.0;
    let badge = if fc.is_entry {
        format!(r##"<text x="{}" y="{}" fill="#ffd700" font-size="9" font-weight="bold" text-anchor="end" opacity="0.85">⬡ ENTRY</text>"##, f(x + T_CARD_W - 12.0), f(name_y))
    } else { String::new() };
    let _ = write!(s, r##"<text x="{}" y="{}" fill="{}" font-size="14" font-weight="bold">{}</text>{}"##,
        f(x + 16.0), f(name_y), if fc.is_entry { "#ffd700" } else { "#d0d0f0" }, esc(&fc.name), badge);

    let stats_y = name_y + 18.0;
    let params = if fc.params.is_empty() { String::new() } else { format!("({})", fc.params.join(", ")) };
    let mut st = Vec::new();
    if fc.vtex > 0 { st.push(format!("{} vtex", fc.vtex)); }
    if fc.audio > 0 { st.push(format!("{} audio", fc.audio)); }
    if fc.has_loop { st.push("↺ loop".into()); }
    let _ = write!(s,
        r##"<text x="{}" y="{}" fill="#52528a" font-size="10">{}</text>
           <text x="{}" y="{}" fill="#52528a" font-size="10" text-anchor="end">{}</text>
           <line x1="{}" y1="{}" x2="{}" y2="{}" stroke="#22225a" stroke-width="1"/>"##,
        f(x + 16.0), f(stats_y), esc(&params),
        f(x + T_CARD_W - 12.0), f(stats_y), esc(&st.join("  ·  ")),
        f(x + 12.0), f(stats_y + 6.0), f(x + T_CARD_W - 12.0), f(stats_y + 6.0));

    let iy0 = stats_y + 6.0 + 5.0 + T_ICON / 2.0;
    let ix0 = x + 16.0 + T_ICON / 2.0;
    let ir = T_ICON / 2.0 * 0.82;
    for (i, c) in fc.calls.iter().enumerate() {
        let row = i / T_ICONS_ROW; let col = i % T_ICONS_ROW;
        let ix = ix0 + col as f32 * (T_ICON + 5.0);
        let iy = iy0 + row as f32 * (T_ICON + 5.0);
        let _ = write!(s, r##"<rect x="{}" y="{}" width="{}" height="{}" rx="3" fill="{}" opacity="0.12"/>"##,
            f(ix - T_ICON / 2.0), f(iy - T_ICON / 2.0), f(T_ICON), f(T_ICON), c.cat.color());
        s.push_str(&icon(c.cat, ix, iy, ir));
        if c.count > 1 {
            let _ = write!(s, r##"<rect x="{}" y="{}" width="13" height="10" rx="3" fill="{}" opacity="0.9"/>
                                  <text x="{}" y="{}" fill="#0a0a1a" font-size="8" font-weight="bold" text-anchor="middle">{}</text>"##,
                f(ix + ir - 2.0), f(iy - ir - 1.0), c.cat.color(),
                f(ix + ir + 4.5), f(iy - ir + 7.0), c.count);
        }
    }
    s
}

// ══════════════════════════════════════════════════════════════════════════════
// 2. ARTWORK — text-free cubist sigil: translucent stars/polygons per file
// ══════════════════════════════════════════════════════════════════════════════

const A_CELL: f32 = 620.0;

fn render_artwork(p: &Project) -> String {
    let nf = p.files.len().max(1);
    let cols = (nf as f32).sqrt().ceil() as usize;
    let rows = (nf + cols - 1) / cols;
    let w = cols as f32 * A_CELL;
    let h = rows as f32 * A_CELL;

    let mut body = String::new();
    body.push_str(DEFS_A);

    // Deep gradient field + a few huge faint background facets (cubist ground).
    let _ = write!(body, r##"<rect width="{}" height="{}" fill="url(#agrad)"/>"##, f(w), f(h));
    let seed = hash(&p.name);
    for i in 0..7u64 {
        let cx = frand(seed, i) * w;
        let cy = frand(seed, i + 100) * h;
        let r = 120.0 + frand(seed, i + 200) * 260.0;
        let sides = 3 + (i % 5) as usize;
        let hue = (i * 47) % 360;
        let _ = write!(body, r##"<polygon points="{}" fill="hsl({},55%,55%)" opacity="0.05"/>"##,
            ngon_points(cx, cy, r, sides, frand(seed, i + 300) * 6.28), hue);
    }

    // Per-file constellations.
    let mut centroids: Vec<(f32, f32)> = Vec::new();
    for (fi, fs) in p.files.iter().enumerate() {
        let gx = (fi % cols) as f32 * A_CELL + A_CELL / 2.0;
        let gy = (fi / cols) as f32 * A_CELL + A_CELL / 2.0;
        centroids.push((gx, gy));
        let fseed = hash(&fs.label);

        // Each function = a node placed by golden-angle phyllotaxis around the cell
        // centre; each of its calls = a translucent star/polygon around that node.
        let ga = 2.399963f32; // golden angle
        for (qi, fc) in fs.funcs.iter().enumerate() {
            let rr = 36.0 + 150.0 * ((qi as f32 + 0.5) / fs.funcs.len().max(1) as f32).sqrt();
            let na = qi as f32 * ga;
            let fx = gx + rr * na.cos();
            let fy = gy + rr * na.sin();

            // faint tether to cell centre
            let _ = write!(body, r##"<line x1="{}" y1="{}" x2="{}" y2="{}" stroke="#ffffff" stroke-width="1" opacity="0.06"/>"##,
                f(gx), f(gy), f(fx), f(fy));

            let shapes = fc.calls.iter().map(|c| c.count).sum::<usize>().max(1).min(14);
            let fnseed = hash(&fc.name) ^ fseed;
            let pal: Vec<&str> = if fc.calls.is_empty() { vec!["#6ab0f5"] } else { fc.calls.iter().map(|c| c.cat.color()).collect() };
            for si in 0..shapes {
                let ang = frand(fnseed, si as u64) * 6.2831853;
                let dist = frand(fnseed, si as u64 + 7) * 30.0;
                let sx = fx + dist * ang.cos();
                let sy = fy + dist * ang.sin();
                let ro = 14.0 + frand(fnseed, si as u64 + 11) * 34.0 + if fc.is_entry { 16.0 } else { 0.0 };
                let col = pal[si % pal.len()];
                let cat = fc.calls.get(si % fc.calls.len().max(1)).map(|c| c.cat).unwrap_or(Cat::User);
                let sides = shape_sides(cat, &fc.name);
                let rot = frand(fnseed, si as u64 + 23) * 6.2831853;
                let op = 0.28 + frand(fnseed, si as u64 + 31) * 0.30;
                // alternate filled star vs polygon for rhythm
                let pts = if si % 2 == 0 { star_points(sx, sy, ro, ro * 0.45, sides, rot) }
                          else { ngon_points(sx, sy, ro, sides, rot) };
                let _ = write!(body, r##"<polygon points="{}" fill="{}" opacity="{:.2}" stroke="{}" stroke-width="0.6" stroke-opacity="0.4"/>"##,
                    pts, col, op, col);
            }
            // bright core for entry points
            if fc.is_entry {
                let _ = write!(body, r##"<circle cx="{}" cy="{}" r="9" fill="#ffd700" opacity="0.9"/>"##, f(fx), f(fy));
            }
        }
    }

    // Faint cross-file relationship arcs between cell centroids (program weave).
    for (i, &(x0, y0)) in centroids.iter().enumerate() {
        for &(x1, y1) in centroids.iter().skip(i + 1) {
            let mx = (x0 + x1) / 2.0; let my = (y0 + y1) / 2.0 - 60.0;
            let _ = write!(body, r##"<path d="M {},{} Q {},{} {},{}" fill="none" stroke="#ffffff" stroke-width="0.8" opacity="0.05"/>"##,
                f(x0), f(y0), f(mx), f(my), f(x1), f(y1));
        }
    }

    svg_doc(w, h, "", &body)
}

const DEFS_A: &str = r##"<defs>
  <radialGradient id="agrad" cx="50%" cy="42%" r="75%">
    <stop offset="0%" stop-color="#171733"/><stop offset="55%" stop-color="#0c0c1e"/><stop offset="100%" stop-color="#050510"/>
  </radialGradient>
</defs>"##;

// ══════════════════════════════════════════════════════════════════════════════
// 3. LING — harmonious file panels of colour-coded named tiles
// ══════════════════════════════════════════════════════════════════════════════

const L_MARGIN: f32 = 40.0;
const L_TILE_W: f32 = 188.0;
const L_TILE_H: f32 = 84.0;
const L_TILE_GAP: f32 = 16.0;
const L_PANEL_PAD: f32 = 22.0;
const L_TITLE_H: f32 = 92.0;

fn render_ling(p: &Project) -> String {
    // Choose a tile column count that keeps panels balanced (square-ish).
    let max_funcs = p.files.iter().map(|f| f.funcs.len()).max().unwrap_or(1).max(1);
    let tiles_per_row = ((max_funcs as f32).sqrt().ceil() as usize).clamp(2, 6);
    let panel_w = L_PANEL_PAD * 2.0 + tiles_per_row as f32 * (L_TILE_W + L_TILE_GAP) - L_TILE_GAP;
    let w = panel_w + L_MARGIN * 2.0;

    // Layout panels top-to-bottom, centred.
    let mut panels: Vec<(usize, f32, f32)> = Vec::new(); // (file index, y, height)
    let mut y = L_TITLE_H + 12.0;
    for (fi, fs) in p.files.iter().enumerate() {
        let n = fs.funcs.len().max(1);
        let rows = (n + tiles_per_row - 1) / tiles_per_row;
        let body_h = rows as f32 * (L_TILE_H + L_TILE_GAP) - L_TILE_GAP;
        let glob_h = if fs.globals.is_empty() && fs.uses.is_empty() { 0.0 } else { 30.0 };
        let ph = 44.0 + body_h + glob_h + L_PANEL_PAD;
        panels.push((fi, y, ph));
        y += ph + 26.0;
    }
    let h = y + L_MARGIN;

    let mut body = String::new();
    body.push_str(DEFS_L);

    // Title
    let _ = write!(body,
        r##"<text x="{}" y="42" fill="#ffd700" font-size="11" font-weight="bold" letter-spacing="3" opacity="0.75">灵 · LING · AST</text>
            <text x="{}" y="78" fill="#e6e6ff" font-size="30" font-weight="bold">{}</text>
            <text x="{}" y="78" fill="#6a6aa0" font-size="13" text-anchor="end">{} files · {} fns</text>"##,
        f(L_MARGIN), f(L_MARGIN), esc(&p.name), f(w - L_MARGIN), p.files.len(), p.total_funcs());

    for (fi, py, ph) in &panels {
        let fs = &p.files[*fi];
        let px = L_MARGIN;
        // Panel frame
        let _ = write!(body,
            r##"<rect x="{}" y="{}" width="{}" height="{}" rx="16" fill="#101028" stroke="#26264e" stroke-width="1.2"/>
                <rect x="{}" y="{}" width="{}" height="34" rx="16" fill="#16163a"/>
                <text x="{}" y="{}" fill="#9bd8ff" font-size="15" font-weight="bold">▦ {}</text>
                <text x="{}" y="{}" fill="#6a6aa0" font-size="11" text-anchor="end">{} fns</text>"##,
            f(px), f(*py), f(panel_w), f(*ph),
            f(px), f(*py), f(panel_w),
            f(px + 16.0), f(py + 23.0), esc(&fs.label),
            f(px + panel_w - 14.0), f(py + 23.0), fs.funcs.len());

        // Tiles
        let t0y = py + 44.0;
        for (i, fc) in fs.funcs.iter().enumerate() {
            let row = i / tiles_per_row; let col = i % tiles_per_row;
            let tx = px + L_PANEL_PAD + col as f32 * (L_TILE_W + L_TILE_GAP);
            let ty = t0y + row as f32 * (L_TILE_H + L_TILE_GAP);
            body.push_str(&l_tile(fc, tx, ty));
        }

        // Globals / uses strip
        if !fs.globals.is_empty() || !fs.uses.is_empty() {
            let rows = (fs.funcs.len().max(1) + tiles_per_row - 1) / tiles_per_row;
            let gy = t0y + rows as f32 * (L_TILE_H + L_TILE_GAP) + 6.0;
            let mut parts: Vec<String> = fs.globals.iter().map(|(n, v)| format!("◇ {n} = {v}")).collect();
            parts.extend(fs.uses.iter().map(|u| format!("⇥ use {u}")));
            let _ = write!(body, r##"<text x="{}" y="{}" fill="#6a6aa0" font-size="11">{}</text>"##,
                f(px + L_PANEL_PAD), f(gy), esc(&parts.join("     ")));
        }
    }

    svg_doc(w, h, &bg_rect(w, h, "#08081a"), &body)
}

const DEFS_L: &str = r##"<defs>
  <filter id="tile-sh" x="-20%" y="-20%" width="140%" height="160%"><feDropShadow dx="0" dy="2" stdDeviation="2" flood-color="#000000" flood-opacity="0.45"/></filter>
</defs>"##;

fn l_tile(fc: &Func, x: f32, y: f32) -> String {
    let dom = fc.calls.iter().max_by_key(|c| c.count).map(|c| c.cat).unwrap_or(Cat::User);
    let col = if fc.is_entry { "#ffd700" } else { dom.color() };
    let mut s = String::new();
    let _ = write!(s,
        r##"<rect x="{}" y="{}" width="{}" height="{}" rx="12" fill="#191940" stroke="{}" stroke-width="{}" filter="url(#tile-sh)"/>
           <rect x="{}" y="{}" width="{}" height="7" rx="3" fill="{}"/>"##,
        f(x), f(y), f(L_TILE_W), f(L_TILE_H), col, if fc.is_entry { 2.4 } else { 1.2 },
        f(x + 10.0), f(y + 12.0), f(L_TILE_W - 20.0), col);

    // Name (truncated to fit)
    let name = if fc.name.chars().count() > 20 { format!("{}…", fc.name.chars().take(19).collect::<String>()) } else { fc.name.clone() };
    let _ = write!(s, r##"<text x="{}" y="{}" fill="{}" font-size="14" font-weight="bold">{}{}</text>"##,
        f(x + 12.0), f(y + 38.0), if fc.is_entry { "#ffd700" } else { "#e0e0ff" },
        if fc.is_entry { "⬡ " } else { "" }, esc(&name));

    // Category dots (one per distinct call category, up to 7)
    let mut seen = HashSet::new();
    let mut dots: Vec<Cat> = Vec::new();
    for c in &fc.calls { if seen.insert(c.cat) { dots.push(c.cat); } }
    for (i, c) in dots.iter().take(7).enumerate() {
        let _ = write!(s, r##"<circle cx="{}" cy="{}" r="4.5" fill="{}"/>"##,
            f(x + 16.0 + i as f32 * 13.0), f(y + 56.0), c.color());
    }

    // Stats line
    let mut st = Vec::new();
    if !fc.params.is_empty() { st.push(format!("{}p", fc.params.len())); }
    if fc.calls.len() > 0 { st.push(format!("{} calls", fc.calls.iter().map(|c| c.count).sum::<usize>())); }
    if fc.has_loop { st.push("↺".into()); }
    let _ = write!(s, r##"<text x="{}" y="{}" fill="#7a7ab0" font-size="10" text-anchor="end">{}</text>"##,
        f(x + L_TILE_W - 12.0), f(y + L_TILE_H - 10.0), esc(&st.join("  ")));
    s
}