import { describe, expect, it } from "vitest";
import type { FontScopeTables } from "./FontKnobStyles";
import { buildFontKnobCss, fontCategoryMetrics } from "./FontKnobStyles";
import type { FontCategory } from "./knobs";

const FAMILIES: Partial<Record<FontCategory, string>> = {
  slab: "'Roboto Slab', 'Rockwell', 'Courier New', serif",
  mono: "monospace",
  blackletter: "'UnifrakturCook', 'Fraktur', serif",
};

const resolveFamily = (category: FontCategory) => FAMILIES[category];
const noTables = () => undefined;

// Inter-shaped tables: display sizes tight (~1.16), small sizes loose, and
// negative display tracking — the exact shape the floors exist to correct.
const TABLES: Record<"heading" | "body", FontScopeTables> = {
  heading: {
    size: { 7: 28, 10: 64 },
    lineHeight: { 7: 38, 10: 74 },
    letterSpacing: { 7: 0, 10: -3 },
  },
  body: {
    size: { 4: 14, 10: 46 },
    lineHeight: { 4: 24, 10: 56 },
    // positive caption tracking (tracking-by-size curve) + negative display
    letterSpacing: { 1: 0.05, 10: -3 },
  },
};
const resolveTables = (scope: "heading" | "body") => TABLES[scope];

describe("buildFontKnobCss", () => {
  it("emits only zero-specificity default leading when both knobs are at the sans-serif default (LC-11)", () => {
    const css = buildFontKnobCss("sans-serif", "sans-serif", resolveFamily, noTables);
    expect(css).toContain(":where(:root .font_heading) { line-height: 1.25; }");
    expect(css).toContain(":where(:root .font_body) { line-height: 1.5; }");
    expect(css).not.toContain("--f-family");
  });

  it("overrides the heading font scope for a non-default headingFont", () => {
    const css = buildFontKnobCss("slab", "sans-serif", resolveFamily, noTables);
    expect(css).toContain(
      ":root .font_heading { --f-family: 'Roboto Slab', 'Rockwell', 'Courier New', serif !important; }",
    );
  });

  it("overrides the body font scope for a non-default bodyFont", () => {
    const css = buildFontKnobCss("sans-serif", "mono", resolveFamily, noTables);
    expect(css).toContain(":root .font_body { --f-family: monospace !important; }");
  });

  it("overrides both scopes independently", () => {
    const css = buildFontKnobCss("blackletter", "mono", resolveFamily, noTables);
    expect(css).toContain("--f-family: 'UnifrakturCook', 'Fraktur', serif !important");
    expect(css).toContain(":root .font_body { --f-family: monospace !important");
  });

  it("emits a fallback --f-family when serif is not registered in Tamagui (live SHC)", () => {
    // Live console 2026-08-29: #mp-font-knob-styles was present but had no
    // --f-family because SHC never registers a `serif` font. The knob still
    // has to write a family, or headingFont/bodyFont are a no-op on painted
    // $heading/$body text. Georgia is a system face — no webfont required.
    const css = buildFontKnobCss("serif", "sans-serif", resolveFamily, noTables);
    expect(css).toContain(
      ":root .font_heading { --f-family: Georgia, 'Times New Roman', Times, serif !important; }",
    );
    expect(css).toContain(":where(:root .font_heading) { line-height:");
  });

  it("emits a fallback --f-family for other unregistered categories and keeps the category leading", () => {
    const css = buildFontKnobCss("cursive", "cursive", resolveFamily, noTables);
    expect(css).toContain(":root .font_heading { --f-family:");
    expect(css).toContain("cursive !important");
    // cursive heading floor 1.3 beats the 1.25 minimum; body max(1.5, 1.5)
    expect(css).toContain(":where(:root .font_heading) { line-height: 1.3; }");
    expect(css).toContain(":where(:root .font_body) { line-height: 1.5; }");
  });

  it("lifts heading lineHeight to the category floor only where base leading is tighter", () => {
    // mono heading floor 1.25: $10 base 74/64 = 1.16 -> 80px; $7 base 38/28 = 1.36 -> untouched
    const css = buildFontKnobCss("mono", "sans-serif", resolveFamily, resolveTables);
    expect(css).toContain("--f-lineHeight-10: 80px !important");
    expect(css).not.toContain("--f-lineHeight-7");
  });

  it("lifts body lineHeight to the body floor for large sizes", () => {
    // mono body floor 1.45: $10 base 56/46 = 1.22 -> 67px; $4 base 24/14 = 1.71 -> untouched
    const css = buildFontKnobCss("sans-serif", "mono", resolveFamily, resolveTables);
    expect(css).toContain("--f-lineHeight-10: 67px !important");
    expect(css).not.toContain("--f-lineHeight-4");
  });

  it("zeroes all non-zero tracking for neutral-tracking categories only (LC-11)", () => {
    const mono = buildFontKnobCss("mono", "sans-serif", resolveFamily, resolveTables);
    expect(mono).toContain("--f-letterSpacing-10: 0px !important");
    expect(mono).not.toContain("--f-letterSpacing-7"); // base 0 stays
    // positive caption tracking is also Inter-specific: neutral zeroes it too
    const monoBody = buildFontKnobCss("sans-serif", "mono", resolveFamily, resolveTables);
    expect(monoBody).toContain("--f-letterSpacing-1: 0px !important");
    expect(monoBody).toContain("--f-letterSpacing-10: 0px !important");
    const slab = buildFontKnobCss("slab", "sans-serif", resolveFamily, resolveTables);
    expect(slab).not.toContain("--f-letterSpacing"); // "inherit" tracking
  });

  it("keeps every category's heading floor at or above 1.15 and body at or above 1.4", () => {
    for (const metrics of Object.values(fontCategoryMetrics)) {
      expect(metrics.heading).toBeGreaterThanOrEqual(1.15);
      expect(metrics.body).toBeGreaterThanOrEqual(1.4);
    }
  });
});