{
  "$schema": "https://raw.githubusercontent.com/martinring/tmlanguage/master/tmlanguage.json",
  "name": "Flux",
  "scopeName": "source.flux",
  "fileTypes": ["flux"],
  "patterns": [
    { "include": "#line-comment" },
    { "include": "#block-comment" },
    { "include": "#string" },
    { "include": "#char" },
    { "include": "#number" },
    { "include": "#fn-def" },
    { "include": "#struct-def" },
    { "include": "#control-keywords" },
    { "include": "#decl-keywords" },
    { "include": "#type-keywords" },
    { "include": "#boolean-literals" },
    { "include": "#operator-keywords" },
    { "include": "#operators" },
    { "include": "#punctuation" }
  ],
  "repository": {

    "line-comment": {
      "name": "comment.line.double-slash.flux",
      "match": "//.*$"
    },

    "block-comment": {
      "name": "comment.block.flux",
      "begin": "/\\*",
      "end": "\\*/",
      "beginCaptures": { "0": { "name": "punctuation.definition.comment.begin.flux" } },
      "endCaptures":   { "0": { "name": "punctuation.definition.comment.end.flux" } }
    },

    "string": {
      "name": "string.quoted.double.flux",
      "begin": "\"",
      "end": "\"",
      "beginCaptures": { "0": { "name": "punctuation.definition.string.begin.flux" } },
      "endCaptures":   { "0": { "name": "punctuation.definition.string.end.flux" } },
      "patterns": [ { "include": "#escape-sequence" } ]
    },

    "char": {
      "name": "string.quoted.single.flux",
      "begin": "'",
      "end": "'",
      "beginCaptures": { "0": { "name": "punctuation.definition.string.begin.flux" } },
      "endCaptures":   { "0": { "name": "punctuation.definition.string.end.flux" } },
      "patterns": [ { "include": "#escape-sequence" } ]
    },

    "escape-sequence": {
      "name": "constant.character.escape.flux",
      "match": "\\\\([nrt\\\\\"'0]|u\\{[0-9a-fA-F]{1,6}\\})"
    },

    "number": {
      "patterns": [
        {
          "comment": "Floating-point: 3.14, 1.0e-9, 2e4",
          "name": "constant.numeric.float.flux",
          "match": "\\b\\d[\\d_]*\\.\\d[\\d_]*(?:[eE][+-]?\\d[\\d_]*)?\\b|\\b\\d[\\d_]*[eE][+-]?\\d[\\d_]*\\b"
        },
        {
          "comment": "Hexadecimal integer: 0xFF, 0xDEAD_BEEF",
          "name": "constant.numeric.integer.hex.flux",
          "match": "\\b0x[0-9a-fA-F][0-9a-fA-F_]*\\b"
        },
        {
          "comment": "Octal integer: 0o77",
          "name": "constant.numeric.integer.octal.flux",
          "match": "\\b0o[0-7][0-7_]*\\b"
        },
        {
          "comment": "Binary integer: 0b1010",
          "name": "constant.numeric.integer.binary.flux",
          "match": "\\b0b[01][01_]*\\b"
        },
        {
          "comment": "Decimal integer: 42, 1_000_000",
          "name": "constant.numeric.integer.decimal.flux",
          "match": "\\b\\d[\\d_]*\\b"
        }
      ]
    },

    "fn-def": {
      "comment": "Highlight function name after `fn`",
      "match": "\\b(fn)\\s+([a-zA-Z_][a-zA-Z0-9_]*)",
      "captures": {
        "1": { "name": "keyword.declaration.function.flux" },
        "2": { "name": "entity.name.function.flux" }
      }
    },

    "struct-def": {
      "comment": "Highlight struct name after `struct`",
      "match": "\\b(struct)\\s+([a-zA-Z_][a-zA-Z0-9_]*)",
      "captures": {
        "1": { "name": "keyword.declaration.type.flux" },
        "2": { "name": "entity.name.type.struct.flux" }
      }
    },

    "control-keywords": {
      "name": "keyword.control.flux",
      "match": "\\b(if|else|while|loop|break|continue|return)\\b"
    },

    "decl-keywords": {
      "patterns": [
        {
          "name": "keyword.other.let.flux",
          "match": "\\blet\\b"
        },
        {
          "name": "storage.modifier.mut.flux",
          "match": "\\bmut\\b"
        }
      ]
    },

    "type-keywords": {
      "patterns": [
        {
          "comment": "Primitive numeric types",
          "name": "support.type.primitive.flux",
          "match": "\\b(u8|u16|u32|u64|i8|i16|i32|i64|f32|f64)\\b"
        },
        {
          "comment": "Other primitive types",
          "name": "support.type.primitive.flux",
          "match": "\\b(bool|char)\\b"
        },
        {
          "comment": "Opaque pointer keyword",
          "name": "support.type.opaque.flux",
          "match": "\\bopaque\\b"
        }
      ]
    },

    "boolean-literals": {
      "name": "constant.language.boolean.flux",
      "match": "\\b(true|false)\\b"
    },

    "operator-keywords": {
      "name": "keyword.operator.logical.flux",
      "match": "\\b(and|or)\\b"
    },

    "operators": {
      "patterns": [
        {
          "comment": "Arrow (return type separator) — must precede - and -=",
          "name": "keyword.operator.arrow.flux",
          "match": "->"
        },
        {
          "comment": "Compound assignment operators — must precede shift, comparison, and arithmetic",
          "name": "keyword.operator.assignment.compound.flux",
          "match": "<<=|>>=|\\+=|-=|\\*=|/=|%=|&=|\\|=|\\^="
        },
        {
          "comment": "Shift operators — must precede < and >",
          "name": "keyword.operator.bitwise.shift.flux",
          "match": "<<|>>"
        },
        {
          "comment": "Comparison operators",
          "name": "keyword.operator.comparison.flux",
          "match": "==|!=|<=|>=|<|>"
        },
        {
          "comment": "Assignment — negative lookbehind excludes all compound-assign prefixes",
          "name": "keyword.operator.assignment.flux",
          "match": "(?<![=!<>+\\-*/%&|^])=(?!=)"
        },
        {
          "comment": "Arithmetic: + - * / %",
          "name": "keyword.operator.arithmetic.flux",
          "match": "[+\\-*/%]"
        },
        {
          "comment": "Bitwise and unary: & | ^ ~ !",
          "name": "keyword.operator.bitwise.flux",
          "match": "[&|^~!]"
        }
      ]
    },

    "punctuation": {
      "patterns": [
        { "name": "punctuation.terminator.statement.flux",  "match": ";" },
        { "name": "punctuation.separator.comma.flux",       "match": "," },
        { "name": "punctuation.accessor.dot.flux",          "match": "\\." },
        { "name": "punctuation.separator.colon.flux",       "match": ":" },
        { "name": "punctuation.brackets.round.flux",        "match": "[()]" },
        { "name": "punctuation.brackets.square.flux",       "match": "[\\[\\]]" },
        { "name": "punctuation.brackets.curly.flux",        "match": "[{}]" }
      ]
    }

  }
}