@use 'sass:meta';
@use 'sass:string';

/// Takes a character or a string representation for the name of a character
/// and returns the CSS entity code for that character.
///
/// @param {String} $char-name - The character (if it is available on a standard
/// keyboard), name of the character, or an abbreviated name for the character,
/// being converted into a CSS entity code.
/// @param {Bool} $is-coded [true] - If true and by default, the function will
/// return the entity code for the given character as described by $char-name.
/// If false, the function will instead return the compiled character itself.
///
/// @return {String} - The desired entity code or character wrapped in a string.
///
///  `entity('&')` and `entity('amp')` both return `'\0026'`
///  entity('tm', $is-coded: false) returns `'™'`
///
/// @access public
/// @group Utilities
///
/// @throw Value of $char-name not a valid string.
/// @throw Value of $char-name does not correspond to an avaialable CSS entity code.
@function entity($char-name, $is-coded: true) {
  @if meta.type-of($char-name) != 'string' {
    @error 'Value of $char-name must be of type "string" in entity().';
  }

  // Default entity, the code for a blank space
  $entity-code: '0020';
  $entity: '\0020';

  $char-name: string.to-lower-case($char-name);

  @if $char-name == '&' or string.slice($char-name, 1, 3) == 'amp' {
    $entity-code: '0026';
    $entity: '\0026';
    $entity: '\0026'; // Ampersand: &
  } @else if
    string.slice($char-name, 1, 4) ==
    'copy' or
    $char-name ==
    'cr' or
    $char-name ==
    '©'
  {
    $entity-code: '00A9';
    $entity: '\00A9'; // Copyright: ©
  } @else if
    string.slice($char-name, 1, 3) ==
    'reg' or
    $char-name ==
    'rtm' or
    $char-name ==
    '®'
  {
    $entity-code: '00AE';
    $entity: '\00AE'; // Registered: ®
  } @else if
    string.slice($char-name, 1, 5) ==
    'trade' or
    $char-name ==
    'tm' or
    $char-name ==
    '™'
  {
    $entity-code: '2122';
    $entity: '\2122'; // Trademark: ™
  } @else if $char-name == '$' or $char-name == 'dollar' or $char-name == 'dlr'
  {
    $entity-code: '0024';
    $entity: '\0024'; // Dollar: $
  } @else if $char-name == 'cents' or $char-name == 'cent' or $char-name == '¢'
  {
    $entity-code: '00A2';
    $entity: '\00A2'; // Cents: ¢
  } @else if
    string.slice($char-name, 1, 4) ==
    'euro' or
    $char-name ==
    'eu' or
    $char-name ==
    '€'
  {
    $entity-code: '20AC';
    $entity: '\20AC'; // Euro: €
  } @else if
    string.slice($char-name, 1, 5) ==
    'pound' or
    $char-name ==
    'gbp' or
    $char-name ==
    'quid' or
    $char-name ==
    '£'
  {
    $entity-code: '00A3';
    $entity: '\00A3'; // British Pound: £
  } @else if $char-name == 'yen' or $char-name == 'jpy' or $char-name == '¥' {
    $entity-code: '00A5';
    $entity: '\00A5'; // Japanese Yen ¥
  } @else if $char-name == 'rupee' or $char-name == 'rs' $char-name == '₹' {
    $entity-code: '20B9';
    $entity: '\20B9'; // Indian Rupee ₹
  } @else if $char-name == 'peso' or $char-name == 'mxn' or $char-name == '₱' {
    $entity-code: '20B1';
    $entity: '\20B1'; // Mexican Peso ₱
  } @else if
    $char-name ==
    'currency' or
    $char-name ==
    'curr' or
    $char-name ==
    'universal currency' or
    $char-name ==
    'ucur' or
    $char-name ==
    '¤'
  {
    $entity-code: '00A4';
    $entity: '\00A4'; // Universal currency symbol ¤
  } @else if
    $char-name ==
    'open-quote' or
    $char-name ==
    'openquote' or
    $char-name ==
    'oquote' or
    $char-name ==
    'o-quote' or
    $char-name ==
    'oq' or
    $char-name ==
    'o"' or
    $char-name ==
    'open double quote' or
    $char-name ==
    'open-double-qoote' or
    $char-name ==
    'odq'
  {
    $entity-code: '201C';
    $entity: '\201C'; // Open double quote: “
  } @else if
    $char-name ==
    'close-quote' or
    $char-name ==
    'closed-quote' or
    $char-name ==
    'closequote' or
    $char-name ==
    'closedquote' or
    $char-name ==
    'cquote' or
    $char-name ==
    'c-quote' or
    $char-name ==
    'cq' or
    $char-name ==
    'c"' or
    $char-name ==
    'close double quote' or
    $char-name ==
    'close-double-qoote' or
    $char-name ==
    'cosed double quote' or
    $char-name ==
    'closed-double-quote' or
    $char-name ==
    'cdq'
  {
    $entity-code: '201D';
    $entity: '\201D'; // Close double quote: ”
  } @else if
    $char-name ==
    'ldaq' or
    $char-name == 'ldang' or
    $char-name ==
    'left-double-angle-quote' or
    $char-name ==
    'left double angle quote' or
    $char-name ==
    'left double angle' or
    $char-name ==
    '«'
  {
    $entity-code: '00AB';
    $entity: '\00AB'; // Left-pointing double-angle quotation mark: «
  } @else if
    $char-name ==
    'rdaq' or
    $char-name ==
    'right-double-angle-quote' or
    $char-name ==
    'right double angle quote' or
    $char-name ==
    'rdang' or
    $char-name ==
    'right-double-angle' or
    $char-name ==
    '»'
  {
    $entity-code: '00BB';
    $entity: '\00BB'; // Right-pointing double-angle quation mark: »
  } @else if
    string.slice($char-name, 1, 4) ==
    'apos' or
    $char-name ==
    "'" or
    $char-name ==
    'aps'
  {
    $entity-code: '2019';
    $entity: '\2019'; // Apostrophe: ’
  } @else if
    $char-name ==
    '-' or
    $char-name ==
    'ndash' or
    $char-name ==
    'endash' or
    $char-name ==
    'nd'
  {
    $entity-code: '2013';
    $entity: '\2013'; // En dash: –
  } @else if
    $char-name ==
    '--' or
    $char-name ==
    'mdash' or
    $char-name ==
    'emdash' or
    $char-name ==
    'md'
  {
    $entity-code: '2014';
    $entity: '\2014'; // Em dash: —
  } @else if
    $char-name == '...' or
    string.slice($char-name, 1, 5) ==
    'ellip' or
    string.slice($char-name, 1, 4) ==
    'elip'
  {
    $entity-code: '2026';
    $entity: '\2026'; // Ellipsis: …
  } @else if
    $char-name ==
    '>' or
    $char-name ==
    'greater-than' or
    $char-name ==
    'greaterthan' or
    $char-name ==
    'greater-then' or
    $char-name ==
    'greaterthen'
  {
    $entity-code: '003E';
    $entity: '\003E'; // Greater than symbol: >
  } @else if
    $char-name ==
    '<' or
    $char-name ==
    'less-than' or
    $char-name ==
    'lessthan' or
    $char-name ==
    'less-then' or
    $char-name ==
    'less-then'
  {
    $entity-code: '003C';
    $entity: '\003C'; // Less than symbol: <
  } @else if
    $char-name ==
    '^!' or
    $char-name ==
    'inverted-exclamation' or
    $char-name ==
    'inverted!' or
    $char-name ==
    'invert!' or
    $char-name ==
    'inv!'
  {
    $entity-code: '00A1';
    $entity: '\00A1'; // Inverted exclamation mark ¡
  } @else if
    $char-name ==
    'account-of' or
    $char-name ==
    'accountof' or
    $char-name ==
    'accof' or
    $char-name ==
    'account' or
    $char-name ==
    'acc'
  {
    $entity-code: '2100';
    $entity: '\2100'; // Account Of: ℀
  } @else if string.slice($char-name, 1, 7) == 'address' {
    $entity-code: '2101';
    $entity: '\2101'; // Addressed to the subject of: ℁
  } @else if
    $char-name ==
    'degree' or
    $char-name ==
    'degrees' or
    $char-name ==
    'deg'
  {
    $entity-code: '00B0';
    $entity: '\00B0'; // Degrees: °
  } @else if
    $char-name ==
    'degrees-celcius' or
    $char-name ==
    'degree-celcius' or
    $char-name ==
    'degreescelcius' or
    $char-name ==
    'degreecelcius' or
    $char-name ==
    'celcius' or
    $char-name ==
    'degcel' or
    $char-name ==
    'deg-cel' or
    $char-name ==
    'degree-c' or
    $char-name ==
    'degrees-c' or
    $char-name ==
    'deg-c' or
    $char-name ==
    'degc' or
    $char-name ==
    '℃'
  {
    $entity-code: '2103';
    $entity: '\2103'; // Degrees Celcius: ℃
  } @else if
    $char-name ==
    'degrees-farenheit' or
    $char-name ==
    'degree-farenheit' or
    $char-name ==
    'degreesfarenheit' or
    $char-name ==
    'degreefarenheit' or
    $char-name ==
    'farenheit' or
    $char-name ==
    'faren' or
    $char-name ==
    'degfar' or
    $char-name ==
    'deg-far' or
    $char-name ==
    'deg-faren' or
    $char-name ==
    'deg-f' or
    $char-name ==
    'degree-f' or
    $char-name ==
    'degrees-f' or
    $char-name ==
    'degf' or
    $char-name ==
    '℉'
  {
    $entity-code: '2109';
    $entity: '\2109'; // Degrees Celcius: ℉
  } @else if
    $char-name ==
    'infinity' or
    $char-name ==
    'inf' or
    $char-name ==
    '∞'
  {
    $entity-code: '221E';
    $entity: '\221E'; // Infinity: ∞
  } @else if
    $char-name ==
    'small-triangle--up' or
    $char-name ==
    'sm-tri--up' or
    $char-name ==
    'smalltriangleup' or
    $char-name ==
    'small-triangle-up' or
    $char-name ==
    'smtriup' or
    $char-name ==
    'triangleupsmall' or
    $char-name ==
    'triangle-up-small' or
    $char-name ==
    'triupsm' or
    $char-name ==
    'uptrianglesmall' or
    $char-name ==
    'up-triangle-small' or
    $char-name ==
    'uptrism' or
    $char-name ==
    '▴'
  {
    $entity-code: '25B2';
    $entity: '\25B2'; // Small Triangle - Up: ▴
  } @else if
    $char-name ==
    'small-triangle--down' or
    $char-name ==
    'sm-tri--down' or
    $char-name ==
    'smalltriangledown' or
    $char-name ==
    'small-triangle-down' or
    $char-name ==
    'smtridown' or
    $char-name ==
    'triangledownsmall' or
    $char-name ==
    'triangle-down-small' or
    $char-name ==
    'trismdown' or
    $char-name ==
    'downtrianglesmall' or
    $char-name ==
    'down-triangle-small' or
    $char-name ==
    'downtrism' or
    $char-name ==
    '▾'
  {
    $entity-code: '25BE';
    $entity: '\25BE'; // Small Triangle - Down: ▾
  } @else if
    $char-name ==
    'small-triangle--left' or
    $char-name ==
    'sm-tri--left' or
    $char-name ==
    'smalltriangleleft' or
    $char-name ==
    'small-triangle-left' or
    $char-name ==
    'smtrileft' or
    $char-name ==
    'triangleleftsmall' or
    $char-name ==
    'triangle-left-small' or
    $char-name ==
    'trileftsm' or
    $char-name ==
    'lefttrianglesmall' or
    $char-name ==
    'left-triangle-small' or
    $char-name ==
    'lefttrism' or
    $char-name ==
    '◂'
  {
    $entity-code: '25C2';
    $entity: '\25C2'; // Small Triangle - Left: ◂
  } @else if
    $char-name ==
    'small-triangle--right' or
    $char-name ==
    'sm-tri--right' or
    $char-name ==
    'smalltriangleup' or
    $char-name ==
    'small-triangle-up' or
    $char-name ==
    'smtriup' or
    $char-name ==
    'triangleupsmall' or
    $char-name ==
    'triangle-up-small' or
    $char-name ==
    'triupsm' or
    $char-name ==
    'uptrianglesmall' or
    $char-name ==
    'up-triangle-small' or
    $char-name ==
    'uptrism' or
    $char-name ==
    '▸'
  {
    $entity-code: '25B8';
    $entity: '\25B8'; // Small Triangle - Right: ▸
  } @else if
    $char-name ==
    'nbsp' or
    $char-name ==
    'nobreakspace' or
    $char-name ==
    'non-breaking space' or
    $char-name ==
    'nonbreaking space' or
    $char-name == 'nb '
  {
    $entity-code: '00A0';
    $entity: '\00A0'; // Non-breaking space
  } @else {
    @error 'You must enter an accepted character or string for $char-name in ' +
        'the [ entity() ] function, one that corresponds with an avaialable ' +
        'CSS entity character.';
  }

  @if $is-coded {
    @return unquote("\"\\#{$entity-code}\"");
  } @else {
    @return $entity;
  }
}