builtin.rs

use std::borrow::Cow;

#[derive(Eq, PartialEq, PartialOrd, Ord, Clone, Copy)]
struct UnitDef {
	singular: &'static str,
	plural: &'static str,
	definition: &'static str,
}

// singular, plural (or empty), definition, description
type UnitTuple = (&'static str, &'static str, &'static str, &'static str);

const BASE_UNITS: &[UnitTuple] = &[
	("second", "seconds", "l@!", ""),
	("meter", "meters", "l@!", ""),
	("kilogram", "kilograms", "l@!", ""),
	("kelvin", "", "l@!", ""),
	("ampere", "amperes", "l@!", ""),
	("mole", "moles", "l@!", ""),
	("candela", "candelas", "l@!", ""),
	("neper", "nepers", "l@!", ""),
];

const BASE_UNIT_ABBREVIATIONS: &[UnitTuple] = &[
	("s", "", "s@second", ""),
	("metre", "metres", "l@meter", ""),
	("m", "", "s@meter", ""),
	("gram", "grams", "l@1/1000 kilogram", ""),
	("jin", "jin", "l@1/2 kilogram", ""),
	("g", "", "s@gram", ""),
	("K", "", "s@kelvin", ""),
	("\u{b0}K", "", "=K", ""),
	("amp", "amps", "l@ampere", ""),
	("A", "", "s@ampere", ""),
	("mol", "", "s@mole", ""),
	("cd", "", "s@candela", ""),
	("Np", "", "s@neper", ""),
];

// some temperature scales have special support for conversions
const TEMPERATURE_SCALES: &[UnitTuple] = &[
	("celsius", "", "l@!", ""),
	("\u{b0}C", "", "celsius", ""), // degree symbol
	("oC", "", "=\u{b0}C", ""),
	("rankine", "", "l@5/9 K", ""),
	("\u{b0}R", "", "rankine", ""),
	("fahrenheit", "", "l@!", ""),
	("\u{b0}F", "", "fahrenheit", ""),
	("oF", "", "=\u{b0}F", ""),
];

const BITS_AND_BYTES: &[UnitTuple] = &[
	("bit", "bits", "l@!", ""),
	("bps", "", "s@bits/second", ""),
	("byte", "bytes", "l@8 bits", ""),
	("b", "", "s@bit", ""),
	("B", "", "s@byte", ""),
	("octet", "octets", "l@8 bits", ""),
	("nibble", "nibbles", "l@4 bits", ""),
];

const STANDARD_PREFIXES: &[UnitTuple] = &[
	("quetta", "", "lp@1e30", ""),
	("ronna", "", "lp@1e27", ""),
	("yotta", "", "lp@1e24", ""),
	("zetta", "", "lp@1e21", ""),
	("exa", "", "lp@1e18", ""),
	("peta", "", "lp@1e15", ""),
	("tera", "", "lp@1e12", ""),
	("giga", "", "lp@1e9", ""),
	("mega", "", "lp@1e6", ""),
	("myria", "", "lp@1e4", ""),
	("kilo", "", "lp@1e3", ""),
	("hecto", "", "lp@1e2", ""),
	("deca", "", "lp@1e1", ""),
	("deka", "", "lp@deca", ""),
	("deci", "", "lp@1e-1", ""),
	("centi", "", "lp@1e-2", ""),
	("milli", "", "lp@1e-3", ""),
	("micro", "", "lp@1e-6", ""),
	("nano", "", "lp@1e-9", ""),
	("pico", "", "lp@1e-12", ""),
	("femto", "", "lp@1e-15", ""),
	("atto", "", "lp@1e-18", ""),
	("zepto", "", "lp@1e-21", ""),
	("yocto", "", "lp@1e-24", ""),
	("ronto", "", "lp@1e-27", ""),
	("quecto", "", "lp@1e-30", ""),
	("k", "", "=1000", ""),
	("M", "", "=1,000,000", ""),
	("G", "", "=1,000,000,000", ""),
	("T", "", "=1,000,000,000,000", ""),
];

const NON_STANDARD_PREFIXES: &[UnitTuple] = &[
	("quarter", "", "lp@1/4", ""),
	("semi", "", "lp@0.5", ""),
	("demi", "", "lp@0.5", ""),
	("hemi", "", "lp@0.5", ""),
	("half", "", "lp@0.5", ""),
	("double", "", "lp@2", ""),
	("triple", "", "lp@3", ""),
	("treble", "", "lp@3", ""),
];

const BINARY_PREFIXES: &[UnitTuple] = &[
	("kibi", "", "lp@2^10", ""),
	("mebi", "", "lp@2^20", ""),
	("gibi", "", "lp@2^30", ""),
	("tebi", "", "lp@2^40", ""),
	("pebi", "", "lp@2^50", ""),
	("exbi", "", "lp@2^60", ""),
	("zebi", "", "lp@2^70", ""),
	("yobi", "", "lp@2^80", ""),
	("Ki", "", "=2^10", ""),
	("Mi", "", "=2^20", ""),
	("Gi", "", "=2^30", ""),
	("Ti", "", "=2^40", ""),
];

const NUMBER_WORDS: &[UnitTuple] = &[
	("tithe", "", "=1/10", ""),
	("one", "", "=1", ""),
	("two", "", "=2", ""),
	("couple", "", "=2", ""),
	("three", "", "=3", ""),
	("four", "", "=4", ""),
	("quadruple", "", "=4", ""),
	("five", "", "=5", ""),
	("quintuple", "", "=5", ""),
	("six", "", "=6", ""),
	("sextuple", "", "=6", ""),
	("seven", "", "=7", ""),
	("septuple", "", "=7", ""),
	("eight", "", "=8", ""),
	("octuple", "", "=8", ""),
	("nine", "", "=9", ""),
	("nonuple", "", "=9", ""),
	("ten", "", "=10", ""),
	("decuple", "", "=10", ""),
	("eleven", "", "=11", ""),
	("undecuple", "", "=11", ""),
	("twelve", "", "=12", ""),
	("duodecuple", "", "=12", ""),
	("dozen", "", "=12", ""),
	("thirteen", "", "=13", ""),
	("tredecuple", "", "=13", ""),
	("bakersdozen", "", "=13", ""),
	("fourteen", "", "=14", ""),
	("fifteen", "", "=15", ""),
	("sixteen", "", "=16", ""),
	("seventeen", "", "=17", ""),
	("eighteen", "", "=18", ""),
	("nineteen", "", "=19", ""),
	("twenty", "", "=20", ""),
	("score", "", "=20", ""),
	("thirty", "", "=30", ""),
	("forty", "", "=40", ""),
	("fifty", "", "=50", ""),
	("sixty", "", "=60", ""),
	("seventy", "", "=70", ""),
	("eighty", "", "=80", ""),
	("ninety", "", "=90", ""),
	("hundred", "", "=100", ""),
	("gross", "", "=144", ""),
	("greatgross", "", "=12 gross", ""),
	("thousand", "", "=1000", ""),
	("million", "", "=1e6", ""),
	("billion", "", "=1e9", ""),
	("trillion", "", "=1e12", ""),
	("quadrillion", "", "=1e15", ""),
	("quintillion", "", "=1e18", ""),
	("sextillion", "", "=1e21", ""),
	("septillion", "", "=1e24", ""),
	("octillion", "", "=1e27", ""),
	("nonillion", "", "=1e30", ""),
	("decillion", "", "=1e33", ""),
	("undecillion", "", "=1e36", ""),
	("duodecillion", "", "=1e39", ""),
	("tredecillion", "", "=1e42", ""),
	("quattuordecillion", "", "=1e45", ""),
	("quindecillion", "", "=1e48", ""),
	("sexdecillion", "", "=1e51", ""),
	("septendecillion", "", "=1e54", ""),
	("octodecillion", "", "=1e57", ""),
	("novemdecillion", "", "=1e60", ""),
	("vigintillion", "", "=1e63", ""),
	("unvigintillion", "", "=1e66", ""),
	("duovigintillion", "", "=1e69", ""),
	("trevigintillion", "", "=1e72", ""),
	("quattuorvigintillion", "", "=1e75", ""),
	("quinvigintillion", "", "=1e78", ""),
	("sexvigintillion", "", "=1e81", ""),
	("septenvigintillion", "", "=1e84", ""),
	("octovigintillion", "", "=1e87", ""),
	("novemvigintillion", "", "=1e90", ""),
	("trigintillion", "", "=1e93", ""),
	("untrigintillion", "", "=1e96", ""),
	("duotrigintillion", "", "=1e99", ""),
	("googol", "", "=1e100", ""),
	("tretrigintillion", "", "=1e102", ""),
	("quattuortrigintillion", "", "=1e105", ""),
	("quintrigintillion", "", "=1e108", ""),
	("sextrigintillion", "", "=1e111", ""),
	("septentrigintillion", "", "=1e114", ""),
	("octotrigintillion", "", "=1e117", ""),
	("novemtrigintillion", "", "=1e120", ""),
	("centillion", "", "=1e303", ""),
];

const CONSTANTS: &[UnitTuple] = &[
	(
		"c",
		"",
		"=299792458 m/s",
		"speed of light in vacuum (exact)",
	),
	(
		"planck",
		"",
		"=6.62607015e-34 J s",
		"Planck constant (exact)",
	),
	(
		"boltzmann",
		"",
		"=1.380649e-23 J/K",
		"Boltzmann constant (exact)",
	),
	("electron_charge", "", "=1.602176634e-19 coulomb", ""),
	("electroncharge", "", "=electron_charge", ""),
	("electronmass", "", "=9.1093837015e-31 kg", ""),
	("electron_mass", "", "=electronmass", ""),
	("protonmass", "", "=1.67262192369e-27 kg", ""),
	("proton_mass", "", "=protonmass", ""),
	("neutronmass", "", "=1.67492749804e-27 kg", ""),
	("neutron_mass", "", "=neutronmass", ""),
	(
		"avogadro",
		"",
		"=6.02214076e23 / mol",
		"size of a mole (exact)",
	),
	("N_A", "", "=avogadro", ""),
	(
		"gravitational_constant",
		"",
		"=6.67430e-11 N m^2 / kg^2",
		"gravitational constant",
	),
	("gravity", "", "=9.80665 m/s^2", ""),
	("force", "", "gravity", ""), // used to convert some units
];

const ANGLES: &[UnitTuple] = &[
	("radian", "radians", "l@1", ""),
	("rad", "", "radian", ""),
	("circle", "circles", "l@2 pi radian", ""),
	("degree", "degrees", "l@1/360 circle", ""),
	("deg", "degs", "l@degree", ""),
	("\u{b0}", "", "degree", ""), // degree symbol
	("arcdeg", "arcdegs", "degree", ""),
	("arcmin", "arcmins", "l@1/60 degree", ""),
	("arcminute", "arcminutes", "l@arcmin", ""),
	("arcsec", "arcsecs", "l@1/60 arcmin", ""),
	("arcsecond", "arcseconds", "l@arcsec", ""),
	("rightangle", "rightangles", "l@90 degrees", ""),
	("quadrant", "quadrants", "l@1/4 circle", ""),
	("quintant", "quintants", "l@1/5 circle", ""),
	("sextant", "sextants", "l@1/6 circle", ""),
	(
		"zodiac_sign",
		"zodiac_signs",
		"l@1/12 circle",
		"Angular extent of one sign of the zodiac",
	),
	("turn", "turns", "l@circle", ""),
	("revolution", "revolutions", "l@circle", ""),
	("rev", "revs", "l@circle", ""),
	("gradian", "gradians", "l@1/100 rightangle", ""),
	("gon", "gons", "l@gradian", ""),
	("grad", "", "l@gradian", ""),
	("mas", "", "milliarcsec", ""),
];

const SOLID_ANGLES: &[UnitTuple] = &[
	("steradian", "steradians", "l@1", ""),
	("sr", "sr", "s@steradian", ""),
	("sphere", "spheres", "4 pi steradians", ""),
	(
		"squaredegree",
		"squaredegrees",
		"(1/180)^2 pi^2 steradians",
		"",
	),
	("squareminute", "squareminutes", "(1/60)^2 squaredegree", ""),
	("squaresecond", "squareseconds", "(1/60)^2 squareminute", ""),
	("squarearcmin", "squarearcmins", "squareminute", ""),
	("squarearcsec", "squarearcsecs", "squaresecond", ""),
	(
		"sphericalrightangle",
		"sphericalrightangles",
		"0.5 pi steradians",
		"",
	),
	("octant", "octants", "0.5 pi steradians", ""),
];

const COMMON_SI_DERIVED_UNITS: &[UnitTuple] = &[
	("newton", "newtons", "l@kg m / s^2", "force"),
	("N", "", "s@newton", ""),
	("pascal", "pascals", "l@N/m^2", "pressure or stress"),
	("Pa", "", "s@pascal", ""),
	("joule", "joules", "l@N m", "energy"),
	("J", "", "s@joule", ""),
	("watt", "watts", "l@J/s", "power"),
	("W", "", "s@watt", ""),
	(
		"horsepower",
		"horsepowers",
		"l@745.69987158227022 watts",
		"",
	),
	("hp", "", "s@horsepower", ""),
	("coulomb", "", "l@A s", "charge"),
	("C", "", "s@coulomb", ""),
	("volt", "volts", "l@W/A", "potential difference"),
	("V", "", "s@volt", ""),
	("Ah", "", "s@ampere hour", ""),
	("ohm", "ohms", "l@V/A", "electrical resistance"),
	("siemens", "", "l@A/V", "electrical conductance"),
	("S", "", "s@siemens", ""),
	("farad", "", "l@coulomb/V", "capacitance"),
	("F", "", "s@farad", ""),
	("weber", "", "l@V s", "magnetic flux"),
	("Wb", "", "s@weber", ""),
	("henry", "", "l@V s / A", "inductance"),
	("H", "", "s@henry", ""),
	("tesla", "", "l@Wb/m^2", "magnetic flux density"),
	("T", "", "s@tesla", ""),
	("hertz", "", "l@/s", "frequency"),
	("Hz", "", "s@hertz", ""),
	("nit", "nits", "l@candela / meter^2", "luminance"),
	("nt", "", "nit", ""),
	("lumen", "lumens", "l@cd sr", "luminous flux"),
	("lm", "", "s@lumen", ""),
	("lux", "", "l@lm/m^2", "illuminance"),
	("lx", "", "lux", "illuminance"),
	("phot", "phots", "l@1e4 lx", ""),
	("ph", "", "s@phot", ""),
	("becquerel", "becquerels", "l@/s", "radioactivity"),
	("Bq", "", "s@becquerel", ""),
	("curie", "curies", "l@3.7e10 Bq", ""),
	("Ci", "", "s@curie", ""),
	("rutherford", "rutherfords", "l@1e6 Bq", ""),
	("Rd", "", "s@rutherford", ""),
	(
		"gray",
		"grays",
		"l@J/kg",
		"absorbed dose of ionising radiation",
	),
	("Gy", "", "s@gray", ""),
	("rad_radiation", "", "l@1/100 Gy", ""),
	(
		"sievert",
		"sieverts",
		"l@J / kg",
		"equivalent dose of ionising radiation",
	),
	("Sv", "", "s@sievert", ""),
	("rem", "", "l@1/100 Sv", ""),
	("roentgen", "roentgens", "l@0.000258 coulomb/kg", ""),
	("R", "", "s@roentgen", ""),
];

const TIME_UNITS: &[UnitTuple] = &[
	("sec", "secs", "s@second", ""),
	("minute", "minutes", "l@60 seconds", ""),
	("min", "mins", "s@minute", ""),
	("hour", "hours", "l@60 minutes", ""),
	("hr", "hrs", "s@hour", ""),
	("h", "h", "s@hour", ""),
	("day", "days", "l@24 hours", ""),
	("d", "", "s@day", ""),
	("da", "", "s@day", ""),
	("week", "weeks", "l@7 days", ""),
	("wk", "", "s@week", ""),
	("fortnight", "fortnights", "l@14 day", ""),
	(
		"sidereal_year",
		"sidereal_years",
		"365.256363004 days",
		concat!(
			"the time taken for the Earth to complete one revolution of its orbit, ",
			"as measured against a fixed frame of reference (such as the fixed stars, ",
			"Latin sidera, singular sidus)"
		),
	),
	(
		"tropical_year",
		"tropical_years",
		"365.242198781 days",
		"the period of time for the mean ecliptic longitude of the Sun to increase by 360 degrees",
	),
	(
		"anomalistic_year",
		"anomalistic_years",
		"365.259636 days",
		"the time taken for the Earth to complete one revolution with respect to its apsides",
	),
	("year", "years", "l@tropical_year", ""),
	("yr", "", "year", ""),
	("month", "months", "l@1/12 year", ""),
	("mo", "", "month", ""),
	("decade", "decades", "10 years", ""),
	("century", "centuries", "100 years", ""),
	("millennium", "millennia", "1000 years", ""),
	("solar_year", "solar_years", "year", ""),
	("calendar_year", "calendar_years", "365 days", ""),
	("common_year", "common_years", "365 days", ""),
	("leap_year", "leap_years", "366 days", ""),
	("julian_year", "julian_years", "365.25 days", ""),
	("gregorian_year", "gregorian_years", "365.2425 days", ""),
	// french revolutionary time
	("decimal_hour", "decimal_hours", "l@1/10 day", ""),
	(
		"decimal_minute",
		"decimal_minutes",
		"l@1/100 decimal_hour",
		"",
	),
	(
		"decimal_second",
		"decimal_seconds",
		"l@1/100 decimal_minute",
		"",
	),
	("beat", "beats", "l@decimal_minute", "Swatch Internet Time"),
	("scaramucci", "scaramuccis", "11 days", ""),
	("mooch", "mooches", "scaramucci", ""),
	(
		"sol",
		"sols",
		"24 hours 39 minutes 35 seconds",
		"martian day",
	),
];

const RATIOS: &[UnitTuple] = &[
	("\u{2030}", "", "=0.001", ""), // per mille
	("percent", "", "=0.01", ""),
	("%", "", "=percent", ""),
	("bel", "bels", "0.5 * ln(10) neper", ""),
	("decibel", "decibels", "1/10 bel", ""),
	("dB", "", "decibel", ""),
	("mill", "mills", "0.001", ""),
	("ppm", "", "1e-6", ""),
	("parts_per_million", "", "ppm", ""),
	("ppb", "", "1e-9", ""),
	("parts_per_billion", "", "ppb", ""),
	("ppt", "", "1e-12", ""),
	("parts_per_trillion", "", "ppt", ""),
	("karat", "", "1/24", "measure of gold purity"),
	("basispoint", "", "0.01 %", ""),
];

const COMMON_PHYSICAL_UNITS: &[UnitTuple] = &[
	("electron_volt", "electron_volts", "l@electron_charge V", ""),
	("eV", "", "s@electron_volt", ""),
	("light_year", "light_years", "c julian_year", ""),
	("ly", "", "lightyear", ""),
	("light_second", "light_seconds", "c second", ""),
	("light_minute", "light_minutes", "c minute", ""),
	("light_hour", "light_hours", "c hour", ""),
	("light_day", "light_days", "c day", ""),
	("light_speed", "", "c", ""),
	("lightspeed", "", "c", ""),
	("parsec", "parsecs", "l@au / tan(arcsec)", ""),
	("pc", "", "s@parsec", ""),
	(
		"astronomical_unit",
		"astronomical_units",
		"149597870700 m",
		"",
	),
	("au", "", "astronomical_unit", ""),
	("AU", "", "astronomical_unit", ""),
	("barn", "", "l@1e-28 m^2", ""),
	("shed", "", "l@1e-24 barn", ""),
	("cc", "", "cm^3", ""),
	("are", "ares", "l@100 meter^2", ""),
	("liter", "liters", "l@1000 cc", ""),
	("litre", "litres", "liter", ""),
	("l", "", "s@liter", ""),
	("L", "", "s@liter", ""),
	("micron", "microns", "l@micrometer", ""),
	("bicron", "bicrons", "l@picometer", ""),
	("gsm", "", "grams / meter^2", ""),
	("hectare", "hectares", "hectoare", ""),
	("ha", "", "s@hectare", ""),
	("decare", "decares", "l@decaare", ""),
	("da", "", "s@decare", ""),
	("calorie", "calories", "l@4.184 J", ""),
	("cal", "", "s@calorie", ""),
	(
		"british_thermal_unit",
		"british_thermal_units",
		"1055.05585 J",
		"",
	),
	("btu", "", "british_thermal_unit", ""),
	("Wh", "", "s@W hour", ""),
	("atmosphere", "atmospheres", "l@101325 Pa", ""),
	("atm", "", "s@atmosphere", ""),
	("mmHg", "", "l@1/760 atm", "millimeter of mercury"),
	("inHg", "", "l@25.4 mmHg", "inch of mercury"),
	("bar", "", "l@1e5 Pa", "about 1 atmosphere"),
	("diopter", "", "l@/m", "reciprocal of focal length"),
	// sqx:
	("sqnm", "", "=nm^2", ""),
	("squm", "", "=um^2", ""),
	("sqµm", "", "=µm^2", ""),
	("sqmm", "", "=mm^2", ""),
	("sqcm", "", "=cm^2", ""),
	("sqdm", "", "=cm^2", ""),
	("sqm", "", "=m^2", ""),
	("sqkm", "", "=km^2", ""),
	// cbx:
	("cbnm", "", "=nm^3", ""),
	("cbum", "", "=um^3", ""),
	("cbµm", "", "=µm^3", ""),
	("cbmm", "", "=mm^3", ""),
	("cbcm", "", "=cm^3", ""),
	("cbdm", "", "=cm^3", ""),
	("cbm", "", "=m^3", ""),
	("cbkm", "", "=km^3", ""),
	// x2:
	("nm2", "", "=nm^2", ""),
	("um2", "", "=um^2", ""),
	("µm2", "", "=µm^2", ""),
	("mm2", "", "=mm^2", ""),
	("cm2", "", "=cm^2", ""),
	("dm2", "", "=cm^2", ""),
	("m2", "", "=m^2", ""),
	("km2", "", "=km^2", ""),
	// x3:
	("nm3", "", "=nm^3", ""),
	("um3", "", "=um^3", ""),
	("µm3", "", "=µm^3", ""),
	("mm3", "", "=mm^3", ""),
	("cm3", "", "=cm^3", ""),
	("dm3", "", "=cm^3", ""),
	("m3", "", "=m^3", ""),
	("km3", "", "=km^3", ""),
	("gongjin", "", "l@1 kilogram", ""),
	(
		"toe",
		"toe",
		"s@41.868 gigajoules",
		"tonne of oil equivalent",
	),
	("kgoe", "kgoe", "1/1000 toe", "kilogram of oil equivalent"),
	("ton_of_tnt", "", "l@4.184 gigajoules", "TNT equivalent"),
	// TODO remove these compatibility units
	("lightyear", "lightyears", "light_year", ""),
	("light", "", "c", ""),
	("at", "at", "s@kgf/cm^2", "technical atmosphere"),
	("Torr", "Torr", "s@101325/760 Pascals", ""),
	("katal", "", "l@mol/second", "catalytic activity"),
	("kat", "", "s@katal", ""),
];

const CGS_UNITS: &[UnitTuple] = &[
	("gal", "gals", "cm/s^2", "acceleration"),
	("dyne", "dynes", "g*gal", "force"),
	("erg", "ergs", "g*cm^2/s^2", "work, energy"),
	("barye", "baryes", "g/(cm*s^2)", "pressure"),
	("poise", "poises", "g/(cm*s)", ""),
	("stokes", "", "cm^2/s", ""),
	("kayser", "kaysers", "cm^-1", ""),
	("biot", "biots", "10 amperes", ""),
	("emu", "emus", "0.001 A m^2", ""),
	("franklin", "franklins", "dyn^1/2*cm", ""),
	("gauss", "", "10^-4 tesla", ""),
	("maxwell", "maxwells", "10^-8 weber", ""),
	("phot", "phots", "10000 lux", ""),
	("stilb", "stilbs", "10000 candela/m^2", ""),
	// abbrevations
	("gallileo", "gallileos", "gal", ""),
	("dyn", "dyns", "dyne", ""),
	("Ba", "", "barye", ""),
	("P", "", "poise", ""),
	("St", "", "stokes", ""),
	("K", "", "kayser", ""),
	("Bi", "", "biot", ""),
	("Fr", "", "franklin", ""),
	("G", "", "gauss", ""),
	("Mx", "", "maxwell", ""),
	("ph", "", "phot", ""),
	("gf", "", "s@g force", ""),
	("pond", "", "l@gf", ""),
];

const IMPERIAL_UNITS: &[UnitTuple] = &[
	("inch", "inches", "2.54 cm", ""),
	("mil", "mils", "1/1000 inch", ""),
	("\u{2019}", "", "foot", ""), // unicode single quote
	("\u{201d}", "", "inch", ""), // unicode double quote
	("'", "", "foot", ""),
	("\"", "", "inch", ""),
	("foot", "feet", "l@12 inch", ""),
	("sqft", "", "=ft^2", ""),
	("yard", "yards", "l@3 ft", ""),
	("mile", "miles", "l@5280 ft", ""),
	("line", "lines", "1/12 inch", ""),
	("rod", "rods", "5.5 yard", ""),
	("pole", "poles", "rod", ""),
	("perch", "perches", "rod", ""),
	("firkin", "firkins", "90 lb", ""),
	("furlong", "furlongs", "40 rod", ""),
	("statute_mile", "statute_miles", "mile", ""),
	("league", "leagues", "3 mile", ""),
	("chain", "chains", "66 feet", ""),
	("link", "links", "1/100 chain", ""),
	("thou", "", "1/1000 inch", "thousandth of an inch"),
	("acre", "acres", "10 chain^2", ""),
	("section", "sections", "mile^2", ""),
	("township", "townships", "36 sections", ""),
	("homestead", "homesteads", "160 acres", ""),
	("point", "points", "l@1/72 inch", ""),
	("twip", "twips", "l@1/20 point", ""),
	("poppyseed", "poppyseeds", "l@line", ""),
	("pica", "picas", "l@12 points", ""),
	("barleycorn", "barleycorns", "l@4 poppyseed", ""),
	("finger", "fingers", "l@63 points", ""),
	("stick", "sticks", "l@2 inches", ""),
	("palm", "palms", "l@3 inches", ""),
	("digit", "digits", "l@1/4 palms", ""),
	("nail", "nails", "l@3 digits", ""),
	("span", "spans", "l@4 nails", ""),
	("hand", "hands", "l@2 sticks", ""),
	("shaftment", "shaftments", "l@2 palm", ""),
	("cubit", "cubits", "l@2 span", ""),
	("ell", "ells", "l@5 span", ""),
	("skein", "skeins", "l@96 ell", ""),
	("spindle", "spindles", "l@120 skein", ""),
	("link", "links", "l@1/25 rod", ""),
	("fathom", "fathoms", "l@2 yard", ""),
	("shackle", "shackles", "l@15 yard", ""),
	("pace", "paces", "l@5 shaftments", ""),
	("step", "steps", "l@2 paces", ""),
	("grade", "grades", "l@pace", ""),
	("rope", "ropes", "l@4 steps", ""),
	("ramsdens_chain", "", "l@5 rope", ""),
	("roman_mile", "roman_miles", "l@50 ramsdens_chain", ""),
	("gunters_chain", "gunters_chains", "l@4 rod", ""),
	("rack_unit", "rack_units", "l@1.75 inches", ""),
	("U", "", "rack_unit", ""),
];

const LIQUID_UNITS: &[UnitTuple] = &[
	("gallon", "gallons", "231 inch^3", ""),
	("gal", "", "gallon", ""),
	("quart", "quarts", "1/4 gallon", ""),
	("pint", "pints", "1/2 quart", ""),
	("cup", "cups", "1/2 pint", ""),
	("gill", "", "1/4 pint", ""),
	("fluid_ounce", "", "1/16 pint", ""),
	("tablespoon", "tablespoons", "1/2 floz", ""),
	("teaspoon", "teaspoons", "1/3 tablespoon", ""),
	("fluid_dram", "", "1/8 floz", ""),
	("qt", "", "quart", ""),
	("pt", "", "pint", ""),
	("floz", "", "fluid_ounce", ""),
	("tbsp", "", "tablespoon", ""),
	("tbs", "", "tablespoon", ""),
	("tsp", "", "teaspoon", ""),
];

const AVOIRDUPOIS_WEIGHT: &[UnitTuple] = &[
	("pound", "pounds", "0.45359237 kg", ""),
	("lb", "lbs", "pound", ""),
	("grain", "grains", "1/7000 pound", ""),
	("ounce", "ounces", "1/16 pound", ""),
	("oz", "", "ounce", ""),
	("dram", "drams", "1/16 ounce", ""),
	("dr", "", "dram", ""),
	("hundredweight", "hundredweights", "100 pounds", ""),
	("cwt", "", "hundredweight", ""),
	("short_ton", "short_tons", "2000 pounds", ""),
	("quarterweight", "quarterweights", "1/4 short_ton", ""),
	("stone", "stones", "14 pounds", ""),
	("st", "", "stone", ""),
];

const TROY_WEIGHT: &[UnitTuple] = &[
	("troy_pound", "troy_pounds", "5760 grains", ""),
	("troy_ounce", "troy_ounces", "1/12 troy_pound", ""),
	("ozt", "", "troy_ounce", ""),
	("pennyweight", "pennyweights", "1/20 troy_ounce", ""),
	("dwt", "", "pennyweight", ""),
];

const OTHER_WEIGHTS: &[UnitTuple] = &[
	("metric_grain", "metric_grains", "50 mg", ""),
	("carat", "carats", "0.2 grams", ""),
	("ct", "", "carat", ""),
	("jewellers_point", "jewellers_points", "1/100 carat", ""),
	("tonne", "tonnes", "l@1000 kg", ""),
	("t", "", "tonne", ""),
];

const IMPERIAL_ABBREVIATIONS: &[UnitTuple] = &[
	("yd", "", "yard", ""),
	("ch", "", "chain", ""),
	("ft", "", "foot", ""),
	("mph", "", "mile/hr", ""),
	("mpg", "", "mile/gal", ""),
	("kph", "", "km/hr", ""),
	("kmh", "", "km/hr", ""),
	("fpm", "", "ft/min", ""),
	("fps", "", "ft/s", ""),
	("rpm", "", "rev/min", ""),
	("rps", "", "rev/sec", ""),
	("mi", "", "mile", ""),
	("smi", "", "mile", ""),
	("nmi", "", "nautical_mile", ""),
	("mbh", "", "1e3 btu/hour", ""),
	("ipy", "", "inch/year", ""),
	("ccf", "", "100 ft^3", ""),
	("Mcf", "", "1000 ft^3", ""),
	("plf", "", "lb / foot", "pounds per linear foot"),
	("lbf", "", "lb force", ""),
	("psi", "", "pound force / inch^2", ""),
	("fur", "furs", "furlong", ""),
	("fir", "firs", "firkin", ""),
	("ftn", "ftns", "fortnight", ""),
	("sqyd", "", "=yd^2", ""),
	("sqft", "", "=ft^2", ""),
	("sqmi", "", "=mi^2", ""),
	("cbyd", "", "=yd^3", ""),
	("cbft", "", "=ft^3", ""),
	("cbmi", "", "=mi^3", ""),
	("yd2", "", "=yd^2", ""),
	("ft2", "", "=ft^2", ""),
	("mi2", "", "=mi^2", ""),
	("yd3", "", "=yd^3", ""),
	("ft3", "", "=ft^3", ""),
	("mi3", "", "=mi^3", ""),
];

const NAUTICAL_UNITS: &[UnitTuple] = &[
	("fathom", "fathoms", "6 ft", ""),
	("nautical_mile", "nautical_miles", "1852 m", ""),
	("cable", "cables", "1/10 nautical_mile", ""),
	("marine_league", "marine_leagues", "3 nautical_mile", ""),
	("knot", "knots", "nautical_mile / hr", ""),
	("kn", "", "=knots", ""),
	("click", "clicks", "km", ""),
	("NM", "", "nautical_mile", ""),
];

const CURRENCIES: &[UnitTuple] = &[
	("BASE_CURRENCY", "BASE_CURRENCY", "!", ""),
	("dollar", "dollars", "USD", ""),
	("cent", "cents", "0.01 USD", ""),
	("US$", "US$", "USD", ""),
	("$", "$", "USD", ""),
	("euro", "euros", "EUR", ""),
	("\u{20ac}", "\u{20ac}", "EUR", ""), // Euro symbol
	("\u{a3}", "\u{a3}", "GBP", ""),     // £
	("\u{a5}", "\u{a5}", "JPY", ""),     // ¥
	("AU$", "AU$", "AUD", ""),
	("HK$", "HK$", "HKD", ""),
	("NZ$", "NZ$", "NZD", ""),
	("zł", "zł", "PLN", ""), // the local abbreviation for PLN, see https://en.wikipedia.org/wiki/Polish_z%C5%82oty
	("zl", "zl", "PLN", ""),
];

const HISTORICAL_UNITS: &[UnitTuple] = &[
	("shaku", "shaku", "0.303 m", ""),
	("tsubo", "tsubo", "3.306 m^2", ""),
	("tatami", "tatami", "tsubo / 2", ""),
	("tatami_mat", "tatami_mats", "=tatami", ""),
];

// from https://en.wikipedia.org/wiki/ISO_4217
const CURRENCY_IDENTIFIERS: &[&str] = &[
	"AED", "AFN", "ALL", "AMD", "ANG", "AOA", "ARS", "AUD", "AWG", "AZN", "BAM", "BBD", "BDT",
	"BGN", "BHD", "BIF", "BMD", "BND", "BOB", "BOV", "BRL", "BSD", "BTN", "BWP", "BYN", "BZD",
	"CAD", "CDF", "CHE", "CHF", "CHW", "CLF", "CLP", "CNY", "COP", "COU", "CRC", "CUC", "CUP",
	"CVE", "CZK", "DJF", "DKK", "DOP", "DZD", "EGP", "ERN", "ETB", "EUR", "FJD", "FKP", "GBP",
	"GEL", "GHS", "GIP", "GMD", "GNF", "GTQ", "GYD", "HKD", "HNL", "HRK", "HTG", "HUF", "IDR",
	"ILS", "INR", "IQD", "IRR", "ISK", "JMD", "JOD", "JPY", "KES", "KGS", "KHR", "KMF", "KPW",
	"KRW", "KWD", "KYD", "KZT", "LAK", "LBP", "LKR", "LRD", "LSL", "LYD", "MAD", "MDL", "MGA",
	"MKD", "MMK", "MNT", "MOP", "MRU", "MUR", "MVR", "MWK", "MXN", "MXV", "MYR", "MZN", "NAD",
	"NGN", "NIO", "NOK", "NPR", "NZD", "OMR", "PAB", "PEN", "PGK", "PHP", "PKR", "PLN", "PYG",
	"QAR", "RON", "RSD", "RUB", "RWF", "SAR", "SBD", "SCR", "SDG", "SEK", "SGD", "SHP", "SLE",
	"SLL", "SOS", "SRD", "SSP", "STN", "SVC", "SYP", "SZL", "THB", "TJS", "TMT", "TND", "TOP",
	"TRY", "TTD", "TWD", "TZS", "UAH", "UGX", "USD", "USN", "UYI", "UYU", "UYW", "UZS", "VED",
	"VES", "VND", "VUV", "WST", "XAF", "XAG", "XAU", "XBA", "XBB", "XBC", "XBD", "XCD", "XDR",
	"XOF", "XPD", "XPF", "XPT", "XSU", "XTS", "XUA", "XXX", "YER", "ZAR", "ZMW", "ZWL",
];

pub(crate) const ALL_UNIT_DEFS: &[&[UnitTuple]] = &[
	BASE_UNITS,
	BASE_UNIT_ABBREVIATIONS,
	TEMPERATURE_SCALES,
	BITS_AND_BYTES,
	STANDARD_PREFIXES,
	NON_STANDARD_PREFIXES,
	BINARY_PREFIXES,
	NUMBER_WORDS,
	CONSTANTS,
	ANGLES,
	SOLID_ANGLES,
	COMMON_SI_DERIVED_UNITS,
	TIME_UNITS,
	RATIOS,
	COMMON_PHYSICAL_UNITS,
	IMPERIAL_UNITS,
	LIQUID_UNITS,
	AVOIRDUPOIS_WEIGHT,
	TROY_WEIGHT,
	OTHER_WEIGHTS,
	IMPERIAL_ABBREVIATIONS,
	NAUTICAL_UNITS,
	CURRENCIES,
	CGS_UNITS,
	HISTORICAL_UNITS,
];

const SHORT_PREFIXES: &[(&str, &str)] = &[
	("Ki", "sp@kibi"),
	("Mi", "sp@mebi"),
	("Gi", "sp@gibi"),
	("Ti", "sp@tebi"),
	("Pi", "sp@pebi"),
	("Ei", "sp@exbi"),
	("Zi", "sp@zebi"),
	("Yi", "sp@yobi"),
	("Q", "sp@quetta"),
	("R", "sp@ronna"),
	("Y", "sp@yotta"),
	("Z", "sp@zetta"),
	("E", "sp@exa"),
	("P", "sp@peta"),
	("T", "sp@tera"),
	("G", "sp@giga"),
	("M", "sp@mega"),
	("k", "sp@kilo"),
	("h", "sp@hecto"),
	("da", "sp@deka"),
	("d", "sp@deci"),
	("c", "sp@centi"),
	("m", "sp@milli"),
	("u", "sp@micro"),       // alternative to µ
	("\u{b5}", "sp@micro"),  // U+00B5 (micro sign)
	("\u{3bc}", "sp@micro"), // U+03BC (lowercase µ)
	("n", "sp@nano"),
	("p", "sp@pico"),
	("f", "sp@femto"),
	("a", "sp@atto"),
	("z", "sp@zepto"),
	("y", "sp@yocto"),
	("r", "sp@ronto"),
	("q", "sp@quecto"),
];

#[allow(clippy::too_many_lines)]
pub(crate) fn query_unit(
	ident: &str,
	short_prefixes: bool,
	case_sensitive: bool,
) -> Option<(Cow<'static, str>, Cow<'static, str>, Cow<'static, str>)> {
	if short_prefixes {
		for (name, def) in SHORT_PREFIXES {
			if *name == ident || (!case_sensitive && name.eq_ignore_ascii_case(ident)) {
				return Some((Cow::Borrowed(name), Cow::Borrowed(name), Cow::Borrowed(def)));
			}
		}
	}
	if let Ok(idx) = CURRENCY_IDENTIFIERS.binary_search(
		&if case_sensitive {
			ident.to_string()
		} else {
			ident.to_uppercase()
		}
		.as_str(),
	) {
		let name = CURRENCY_IDENTIFIERS[idx];
		return Some((
			Cow::Borrowed(name),
			Cow::Borrowed(name),
			Cow::Borrowed("$CURRENCY"),
		));
	}
	let mut candidates = vec![];
	for group in ALL_UNIT_DEFS {
		for def in *group {
			let def = UnitDef {
				singular: def.0,
				plural: if def.1.is_empty() { def.0 } else { def.1 },
				definition: def.2,
			};
			if def.singular == ident || def.plural == ident {
				return Some((
					Cow::Borrowed(def.singular),
					Cow::Borrowed(def.plural),
					Cow::Borrowed(def.definition),
				));
			}
			if !case_sensitive
				&& (def.singular.eq_ignore_ascii_case(ident)
					|| def.plural.eq_ignore_ascii_case(ident))
			{
				candidates.push(Some((
					Cow::Borrowed(def.singular),
					Cow::Borrowed(def.plural),
					Cow::Borrowed(def.definition),
				)));
			}
		}
	}
	if candidates.len() == 1 {
		return candidates.into_iter().next().unwrap();
	}
	None
}

const DEFAULT_UNITS: &[(&str, &str)] = &[
	("hertz", "second^-1"),
	("newton", "kilogram^1 meter^1 second^-2"),
	("pascal", "kilogram^1 meter^-1 second^-2"),
	("joule", "kilogram^1 meter^2 second^-2"),
	("watt", "kilogram^1 meter^2 second^-3"),
	("ohm", "ampere^-2 kilogram^1 meter^2 second^-3"),
	("volt", "ampere^-1 kilogram^1 meter^2 second^-3"),
	("liter", "meter^3"),
];

pub(crate) fn lookup_default_unit(base_units: &str) -> Option<&str> {
	if let Some((unit_name, _)) = DEFAULT_UNITS.iter().find(|(_, base)| *base == base_units) {
		return Some(unit_name);
	}
	if let Some((singular, _, _, _)) = BASE_UNITS
		.iter()
		.find(|(singular, _, _, _)| format!("{singular}^1") == base_units)
	{
		return Some(singular);
	}
	None
}

/// used for implicit unit addition, e.g. 5'5 -> 5'5"
pub(crate) const IMPLICIT_UNIT_MAP: &[(&str, &str)] = &[("'", "\""), ("foot", "inches")];

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

	fn test_str(s: &str, ctx: &mut crate::Context) {
		if s.is_empty() || s == "'" || s == "\"" {
			return;
		}
		//eprintln!("Testing '{s}'");
		crate::evaluate(s, ctx).unwrap();
	}

	fn test_group(group: &[UnitTuple]) {
		let mut ctx = crate::Context::new();
		ctx.set_exchange_rate_handler_v1(crate::test_utils::dummy_currency_handler);
		for (s, p, _, _) in group {
			test_str(s, &mut ctx);
			test_str(p, &mut ctx);
		}
	}

	#[test]
	fn test_all_units() {
		for &group in ALL_UNIT_DEFS {
			test_group(group);
		}
	}

	#[test]
	fn currencies_sorted() {
		let currencies = CURRENCY_IDENTIFIERS.to_vec();
		let mut sorted = currencies.clone();
		sorted.sort_unstable();
		assert_eq!(currencies, sorted, "currencies are not sorted");
	}

	#[test]
	fn lowercase_currency() {
		assert!(query_unit("usd", true, true).is_none());
		assert!(query_unit("usd", true, false).is_some());
		assert!(query_unit("USD", true, false).is_some());
	}
}