Implement begining of migration

Move Function/Query definition

src/main/kotlin/fr/postgresjson/definition/Function.kt

@@ -0,0 +1,48 @@
+package fr.postgresjson.definition
+
+import java.io.File
+
+
+open class Function (
+    override val name: String,
+    override val script: String,
+    override val parameters: List<Parameter>
+) : Resource, ParametersInterface {
+    override var source: File? = null
+
+    companion object {
+        fun build(source: File): List<Function> {
+            return build(source.readText())
+        }
+
+        fun build(functionContent: String): List<Function> {
+            val functionRegex = """create .*(procedure|function) *(?<name>[^(\s]+)\s*\((?<params>(\s*((IN|OUT|INOUT|VARIADIC)?\s+)?([^\s,)]+\s+)?([^\s,)]+)(\s+(?:default\s|=)\s*[^\s,)]+)?\s*(,|(?=\))))*)\) *(?<return>RETURNS *[^ ]+)?"""
+                .toRegex(setOf(RegexOption.IGNORE_CASE, RegexOption.MULTILINE))
+
+            val paramsRegex = """\s*(?<param>((?<direction>IN|OUT|INOUT|VARIADIC)?\s+)?(?<name>[^\s,)]+\s+)?(?<type>[^\s,)]+)(\s+(?<default>default\s|=)\s*[^\s,)]+)?)\s*(,|$)"""
+                .toRegex(setOf(RegexOption.IGNORE_CASE, RegexOption.MULTILINE))
+
+            return functionRegex.findAll(functionContent).map { queryMatch ->
+                val functionName = queryMatch.groups["name"]?.value?.trim()
+                val functionParameters = queryMatch.groups["params"]?.value?.trim()
+                val returns = queryMatch.groups["return"]?.value?.trim()
+
+                /* Create parameters definition */
+                val parameters = if (functionParameters !== null) {
+                    val matchesParams = paramsRegex.findAll(functionParameters)
+                    matchesParams.map { paramsMatch ->
+                        Parameter(
+                            paramsMatch.groups["name"]!!.value.trim(),
+                            paramsMatch.groups["type"]!!.value.trim(),
+                            paramsMatch.groups["direction"]?.value?.trim(),
+                            paramsMatch.groups["default"]?.value?.trim())
+                    }.toList()
+                } else {
+                    listOf()
+                }
+
+                Function(functionName!!, functionContent, parameters)
+            }.toList()
+        }
+    }
+}