import { compareSteel, findSimilar, getSteel } from "steel-lib";

// Compare two grades by name
const result = compareSteel("40Х", "45Х");
console.log(result?.similarity); // ~0.85

// Find most similar grades
const similar = findSimilar("Ст3");
console.log(similar?.slice(0, 3));
// [
//   { steel: "Сталь 20", similarity: 0.92 },
//   { steel: "Сталь 10", similarity: 0.88 },
//   ...
// ]

// Access raw grade data
const steel = getSteel("12Х18Н10Т");
console.log(steel?.standards.aisi); // "321"
console.log(steel?.chemical_composition.Cr); // { min: 17, max: 19 }

// Find a GOST grade by foreign standard code
import { getSteelByStandard } from "steel-lib";
const gostGrade = getSteelByStandard("304");
console.log(gostGrade?.name); // "08Х18Н10"

// Explain why two grades are similar (ru by default, { lang: "en" } for English)
import { explainSimilarity } from "steel-lib";
const ex = explainSimilarity("Сталь 20", "Сталь 45");
console.log(ex?.summary);     // "Похожи на 72%"
console.log(ex?.factors[0]);  // { key: "C", a: 0.205, b: 0.46, delta: 0.255, text: "Углерод +0.255%" }

// Select grades by spec (AND semantics, empty filter returns all)
import { findBy } from "steel-lib";
const weldable = findBy({ category: "конструкционная легированная", maxCarbon: 0.12 });
const stainless = findBy({ minElement: { Cr: 12 } });

// Chemistry metrics
import { calcPREN, calcCEV } from "steel-lib";
calcPREN(getSteel("10Х17Н13М2Т")!); // ~25.25 — pitting resistance (Cr + 3.3·Mo)
calcCEV(getSteel("09Г2С")!);         // ~0.36 — carbon equivalent (weldability)

type Steel = {
    id: string;                    // "gost-st3", "gost-40x"
    name: string;                  // "Ст3", "40Х"
    category: SteelCategory;       // "конструкционная углеродистая", etc.
    standards: {
        aisi: string | null;       // "1020", "5140", ...
        din_en: string | null;     // "C22 (1.0402)", ...
        gost: string;              // "Ст3", "40Х"
        jis: string | null;        // "SS400", "SCr440", ...
    };
    chemical_composition: {
        C: MinMax; Cr: MinMax; Mo: MinMax; V: MinMax;
        Mn: MinMax; Si: MinMax; Ni: MinMax;
        P: MinMax; S: MinMax; Cu: MinMax;
        Ti?: MinMax; W?: MinMax; Co?: MinMax;
        Al?: MinMax; As?: MinMax;
    };
    mechanical_properties: {
        hardness_hrc: MinMax;
        hardness_hb: MinMax;
        tensile_strength_mpa: number | null;
        yield_strength_mpa: number | null;
        elongation_percent: number | null;
        impact_toughness_j_cm2: number | null;
    };
    physical_properties: {
        density_g_cm3: number | null;
        thermal_conductivity_w_mk: number | null;
    };
    description: string;
};

type MinMax = { min: number | null; max: number | null };