From d4b5c32a2112bb248720706d2295008bd2d68585 Mon Sep 17 00:00:00 2001
From: Sven Heidemann <sven.heidemann@sh-edraft.de>
Date: Tue, 27 Jul 2021 11:57:42 +0200
Subject: [PATCH] Added min and max queries

---
 src/cpl_query/_extension/iterable.py    |  7 ++++
 src/cpl_query/_query/max_min.py         | 48 +++++++++++++++++++++++++
 src/cpl_query/extension/iterable_abc.py |  5 ++-
 src/cpl_query/tests/query_test.py       | 10 +++++-
 4 files changed, 68 insertions(+), 2 deletions(-)
 create mode 100644 src/cpl_query/_query/max_min.py

diff --git a/src/cpl_query/_extension/iterable.py b/src/cpl_query/_extension/iterable.py
index 45180a9c..15037603 100644
--- a/src/cpl_query/_extension/iterable.py
+++ b/src/cpl_query/_extension/iterable.py
@@ -11,6 +11,7 @@ from .._query.distinct import distinct_query
 from .._query.element_at import element_at_query, element_at_or_default_query
 from .._query.first_last import first_or_default_query, first_query, last_or_default_query, last_query
 from .._query.for_each import for_each_query
+from .._query.max_min import max_query, min_query
 from .._query.order_by import order_by_query, order_by_descending_query
 from .._query.single import single_query, single_or_default_query
 from .._query.where import where_query
@@ -63,6 +64,12 @@ class Iterable(IterableABC):
     def for_each(self, func: Callable):
         for_each_query(self, func)
 
+    def max(self, t: type, func: Callable) -> Union[int, float, complex]:
+        return max_query(self, t, func)
+
+    def min(self, t: type, func: Callable) -> Union[int, float, complex]:
+        return min_query(self, t, func)
+
     def order_by(self, func: Callable) -> OrderedIterableABC:
         res = order_by_query(self, func)
         res.__class__ = OrderedIterable
diff --git a/src/cpl_query/_query/max_min.py b/src/cpl_query/_query/max_min.py
new file mode 100644
index 00000000..82dc01c0
--- /dev/null
+++ b/src/cpl_query/_query/max_min.py
@@ -0,0 +1,48 @@
+from collections import Callable
+from typing import Union
+
+from cpl_query.exceptions import ArgumentNoneException, ExceptionArgument, InvalidTypeException
+from cpl_query.extension.iterable_abc import IterableABC
+
+
+def max_query(_list: IterableABC, _t: type, _func: Callable) -> Union[int, float, complex]:
+    if _list is None:
+        raise ArgumentNoneException(ExceptionArgument.list)
+
+    if _func is None:
+        raise ArgumentNoneException(ExceptionArgument.func)
+
+    if _t != int and _t != float and _t != complex:
+        raise InvalidTypeException()
+
+    max_value = _t()
+    for element in _list:
+        value = _func(element)
+        if value > max_value:
+            max_value = value
+
+    return max_value
+
+
+def min_query(_list: IterableABC, _t: type, _func: Callable) -> Union[int, float, complex]:
+    if _list is None:
+        raise ArgumentNoneException(ExceptionArgument.list)
+
+    if _func is None:
+        raise ArgumentNoneException(ExceptionArgument.func)
+
+    if _t != int and _t != float and _t != complex:
+        raise InvalidTypeException()
+
+    min_value = _t()
+    is_first = True
+    for element in _list:
+        value = _func(element)
+        if is_first:
+            min_value = value
+            is_first = False
+
+        if value < min_value:
+            min_value = value
+
+    return min_value
diff --git a/src/cpl_query/extension/iterable_abc.py b/src/cpl_query/extension/iterable_abc.py
index c9d0105b..6a94c8c3 100644
--- a/src/cpl_query/extension/iterable_abc.py
+++ b/src/cpl_query/extension/iterable_abc.py
@@ -45,7 +45,10 @@ class IterableABC(ABC, list):
     def first_or_default(self) -> any: pass
 
     @abstractmethod
-    def for_each(self, func: Callable): pass
+    def for_each(self, func: Callable) -> Union[int, float, complex]: pass
+
+    @abstractmethod
+    def max(self, t: type, func: Callable) -> Union[int, float, complex]: pass
 
     @abstractmethod
     def order_by(self, func: Callable) -> 'IterableABC': pass
diff --git a/src/cpl_query/tests/query_test.py b/src/cpl_query/tests/query_test.py
index 64f5f23c..c5522813 100644
--- a/src/cpl_query/tests/query_test.py
+++ b/src/cpl_query/tests/query_test.py
@@ -28,7 +28,7 @@ class QueryTest(unittest.TestCase):
                 String.random_string(string.ascii_letters, 8).lower(),
                 Address(
                     String.random_string(string.ascii_letters, 10).lower(),
-                    randint(0, 10)
+                    randint(1, 10)
                 )
             )
 
@@ -162,6 +162,14 @@ class QueryTest(unittest.TestCase):
 
         self.assertEqual(len(users), len(self._tests))
 
+    def test_max(self):
+        res = self._tests.max(int, lambda u: u.address.nr)
+        self.assertEqual(self._t_user.address.nr, res)
+
+    def test_min(self):
+        res = self._tests.min(int, lambda u: u.address.nr)
+        self.assertEqual(1, res)
+
     def test_order_by(self):
         res = self._tests.order_by(lambda user: user.address.street)
         res2 = self._tests.order_by(lambda user: user.address.nr)