-- Copyright 2006-2021 Mitchell. See LICENSE.
-- SQL LPeg lexer.

local lexer = require('lexer')
local token, word_match = lexer.token, lexer.word_match
local P, S = lpeg.P, lpeg.S

local lex = lexer.new('sql')

-- Whitespace.
lex:add_rule('whitespace', token(lexer.WHITESPACE, lexer.space^1))

-- Keywords.
lex:add_rule('keyword', token(lexer.KEYWORD, word_match([[
  add all alter analyze and as asc asensitive before between bigint binary blob
  both by call cascade case change char character check collate column condition
  connection constraint continue convert create cross current_date current_time
  current_timestamp current_user cursor database databases day_hour
  day_microsecond day_minute day_second dec decimal declare default delayed
  delete desc describe deterministic distinct distinctrow div double drop dual
  each else elseif enclosed escaped exists exit explain false fetch float for
  force foreign from fulltext goto grant group having high_priority
  hour_microsecond hour_minute hour_second if ignore in index infile inner inout
  insensitive insert int integer interval into is iterate join key keys kill
  leading leave left like limit lines load localtime localtimestamp lock long
  longblob longtext loop low_priority match mediumblob mediumint mediumtext
  middleint minute_microsecond minute_second mod modifies natural not
  no_write_to_binlog null numeric on optimize option optionally or order out
  outer outfile precision primary procedure purge read reads real references
  regexp rename repeat replace require restrict return revoke right rlike schema
  schemas second_microsecond select sensitive separator set show smallint soname
  spatial specific sql sqlexception sqlstate sqlwarning sql_big_result
  sql_calc_found_rows sql_small_result ssl starting straight_join table
  terminated text then tinyblob tinyint tinytext to trailing trigger true undo
  union unique unlock unsigned update usage use using utc_date utc_time
  utc_timestamp values varbinary varchar varcharacter varying when where while
  with write xor year_month zerofill
]], true)))

-- Identifiers.
lex:add_rule('identifier', token(lexer.IDENTIFIER, lexer.word))

-- Strings.
local sq_str = lexer.range("'")
local dq_str = lexer.range('"')
local bq_str = lexer.range('`')
lex:add_rule('string', token(lexer.STRING, sq_str + dq_str + bq_str))

-- Comments.
local line_comment = lexer.to_eol(P('--') + '#')
local block_comment = lexer.range('/*', '*/')
lex:add_rule('comment', token(lexer.COMMENT, line_comment + block_comment))

-- Numbers.
lex:add_rule('number', token(lexer.NUMBER, lexer.number))

-- Operators.
lex:add_rule('operator', token(lexer.OPERATOR, S(',()')))

return lex
