1 files changed, 67 insertions, 0 deletions
diff --git a/src/runMain/kotlin/Lexical.kt b/src/runMain/kotlin/Lexical.kt
new file mode 100644
index 0000000..8529036
--- /dev/null
+++ b/src/runMain/kotlin/Lexical.kt
@@ -0,0 +1,67 @@
+import exceptions.UnknownType
+
+class Lexical {
+    fun analyze(source: String): MutableList<Pair<String, TokenType>> {
+        var buffer = ""
+        var statementEnd = false
+        val tokens = mutableListOf<Pair<String, TokenType>>()
+        for (i in source.indices) {
+            buffer += source[i]
+            statementEnd = source[i] == ';'
+            val tokenType = getTokenType(buffer, if (source.length > i + 1) source[i + 1] else ' ')
+            if (tokenType != TokenType.Skip) {
+                tokens += buffer to tokenType
+                buffer = ""
+            }
+        }
+        return tokens
+    }
+
+    /**
+     * Matches the tokens to a [TokenType]
+     */
+    private fun getTokenType(token: String, next: Char): TokenType {
+        return when {
+            token + next in keyword -> TokenType.Skip
+            token in keyword -> TokenType.Keyword
+
+            token + next in comparison -> TokenType.Skip
+            token in assignment -> TokenType.Assignment
+
+            token + next in assignment -> TokenType.Skip
+            token in arithmetic -> TokenType.Arithmetic
+
+            token + next in comparison -> TokenType.Skip
+            token in comparison -> TokenType.Comparison
+
+            token + next in comparison -> TokenType.Skip
+            token in logical -> TokenType.Logical
+
+            (token + next).matches(Regex("[a-zA-Z]*")) -> TokenType.Skip
+            token.matches(Regex("[a-zA-Z]*")) -> TokenType.Identifier
+
+            (token + next).matches(Regex("[0-9]*")) -> TokenType.Skip
+            token.matches(Regex("[0-9]*")) -> TokenType.Constant
+
+            token.contains(" ") && token.length > 1 -> throw UnknownType(token)
+            token == " " -> TokenType.Empty
+
+            token in punctuation -> TokenType.Punctuation
+
+            token in brackets -> TokenType.Bracket
+
+            token in classifier -> TokenType.Classifier
+
+            else -> TokenType.Skip
+        }
+    }
+
+    private val keyword = listOf("print") // TODO: DataType matching
+    private val assignment = listOf("=", "+=", "-=", "*=", "/*")
+    private val arithmetic = listOf("+", "-", "*", "/", "%")
+    private val comparison = listOf("==", "!=", "<", "<=", ">", ">=")
+    private val logical = listOf("&&", "||", "!")
+    private val punctuation = listOf(",", ":", ".", ";")
+    private val brackets = listOf("(", ")", "[", "]", "{", "}") // TODO: Use brackets for functions
+    private val classifier = listOf("\"", "'")
+}