# Copyright 2017 "Neo Technology",
# Network Engine for Objects in Lund AB (http://neotechnology.com)
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
#

Feature: AggregationAcceptance

  Scenario: Support multiple divisions in aggregate function
    Given an empty graph
    And having executed:
      """
      UNWIND range(0, 7250) AS i
      CREATE ()
      """
    When executing query:
      """
      MATCH (n)
      RETURN count(n) / 60 / 60 AS count
      """
    Then the result should be:
      | count |
      | 2     |
    And no side effects

  Scenario: Support column renaming for aggregates as well
    Given an empty graph
    And having executed:
      """
      UNWIND range(0, 10) AS i
      CREATE ()
      """
    When executing query:
      """
      MATCH ()
      RETURN count(*) AS columnName
      """
    Then the result should be:
      | columnName |
      | 11         |
    And no side effects

  Scenario: Aggregates inside normal functions
    Given an empty graph
    And having executed:
      """
      UNWIND range(0, 10) AS i
      CREATE ()
      """
    When executing query:
      """
      MATCH (a)
      RETURN size(collect(a))
      """
    Then the result should be:
      | size(collect(a)) |
      | 11               |
    And no side effects

  Scenario: Handle aggregates inside non-aggregate expressions
    Given an empty graph
    When executing query:
      """
      MATCH (a {name: 'Andres'})<-[:FATHER]-(child)
      RETURN {foo: a.name='Andres', kids: collect(child.name)}
      """
    Then the result should be empty
    And no side effects

  Scenario: Count nodes
    Given an empty graph
    And having executed:
      """
      CREATE (a:L), (b1), (b2)
      CREATE (a)-[:A]->(b1), (a)-[:A]->(b2)
      """
    When executing query:
      """
      MATCH (a:L)-[rel]->(b)
      RETURN a, count(*)
      """
    Then the result should be:
      | a    | count(*) |
      | (:L) | 2        |
    And no side effects

  Scenario: Sort on aggregate function and normal property
    Given an empty graph
    And having executed:
      """
      CREATE ({division: 'Sweden'})
      CREATE ({division: 'Germany'})
      CREATE ({division: 'England'})
      CREATE ({division: 'Sweden'})
      """
    When executing query:
      """
      MATCH (n)
      RETURN n.division, count(*)
      ORDER BY count(*) DESC, n.division ASC
      """
    Then the result should be, in order:
      | n.division | count(*) |
      | 'Sweden'   | 2        |
      | 'England'  | 1        |
      | 'Germany'  | 1        |
    And no side effects

  Scenario: Aggregate on property
    Given an empty graph
    And having executed:
      """
      CREATE ({x: 33})
      CREATE ({x: 33})
      CREATE ({x: 42})
      """
    When executing query:
      """
      MATCH (n)
      RETURN n.x, count(*)
      """
    Then the result should be:
      | n.x | count(*) |
      | 42  | 1        |
      | 33  | 2        |
    And no side effects

  Scenario: Count non-null values
    Given an empty graph
    And having executed:
      """
      CREATE ({y: 'a', x: 33})
      CREATE ({y: 'a'})
      CREATE ({y: 'b', x: 42})
      """
    When executing query:
      """
      MATCH (n)
      RETURN n.y, count(n.x)
      """
    Then the result should be:
      | n.y | count(n.x) |
      | 'a' | 1          |
      | 'b' | 1          |
    And no side effects

  Scenario: Sum non-null values
    Given an empty graph
    And having executed:
      """
      CREATE ({y: 'a', x: 33})
      CREATE ({y: 'a'})
      CREATE ({y: 'a', x: 42})
      """
    When executing query:
      """
      MATCH (n)
      RETURN n.y, sum(n.x)
      """
    Then the result should be:
      | n.y | sum(n.x) |
      | 'a' | 75       |
    And no side effects

  Scenario: Handle aggregation on functions
    Given an empty graph
    And having executed:
      """
      CREATE (a:L), (b1), (b2)
      CREATE (a)-[:A]->(b1), (a)-[:A]->(b2)
      """
    When executing query:
      """
      MATCH p=(a:L)-[*]->(b)
      RETURN b, avg(length(p))
      """
    Then the result should be:
      | b  | avg(length(p)) |
      | () | 1.0            |
      | () | 1.0            |
    And no side effects

  Scenario: Distinct on unbound node
    Given an empty graph
    When executing query:
      """
      OPTIONAL MATCH (a)
      RETURN count(DISTINCT a)
      """
    Then the result should be:
      | count(DISTINCT a) |
      | 0                 |
    And no side effects

  Scenario: Distinct on null
    Given an empty graph
    And having executed:
      """
      CREATE ()
      """
    When executing query:
      """
      MATCH (a)
      RETURN count(DISTINCT a.foo)
      """
    Then the result should be:
      | count(DISTINCT a.foo) |
      | 0                     |
    And no side effects

  Scenario: Collect distinct nulls
    Given any graph
    When executing query:
      """
      UNWIND [null, null] AS x
      RETURN collect(DISTINCT x) AS c
      """
    Then the result should be:
      | c  |
      | [] |
    And no side effects

  Scenario: Collect distinct values mixed with nulls
    Given any graph
    When executing query:
      """
      UNWIND [null, 1, null] AS x
      RETURN collect(DISTINCT x) AS c
      """
    Then the result should be:
      | c   |
      | [1] |
    And no side effects

  Scenario: Aggregate on list values
    Given an empty graph
    And having executed:
      """
      CREATE ({color: ['red']})
      CREATE ({color: ['blue']})
      CREATE ({color: ['red']})
      """
    When executing query:
      """
      MATCH (a)
      RETURN DISTINCT a.color, count(*)
      """
    Then the result should be:
      | a.color  | count(*) |
      | ['red']  | 2        |
      | ['blue'] | 1        |
    And no side effects

  Scenario: Aggregates in aggregates
    Given any graph
    When executing query:
      """
      RETURN count(count(*))
      """
    Then a SyntaxError should be raised at compile time: NestedAggregation

  Scenario: Aggregates with arithmetics
    Given an empty graph
    And having executed:
      """
      CREATE ()
      """
    When executing query:
      """
      MATCH ()
      RETURN count(*) * 10 AS c
      """
    Then the result should be:
      | c  |
      | 10 |
    And no side effects

  Scenario: Aggregates ordered by arithmetics
    Given an empty graph
    And having executed:
      """
      CREATE (:A), (:X), (:X)
      """
    When executing query:
      """
      MATCH (a:A), (b:X)
      RETURN count(a) * 10 + count(b) * 5 AS x
      ORDER BY x
      """
    Then the result should be, in order:
      | x  |
      | 30 |
    And no side effects

  Scenario: Multiple aggregates on same variable
    Given an empty graph
    And having executed:
      """
      CREATE ()
      """
    When executing query:
      """
      MATCH (n)
      RETURN count(n), collect(n)
      """
    Then the result should be:
      | count(n) | collect(n) |
      | 1        | [()]       |
    And no side effects

  Scenario: Simple counting of nodes
    Given an empty graph
    And having executed:
      """
      UNWIND range(1, 100) AS i
      CREATE ()
      """
    When executing query:
      """
      MATCH ()
      RETURN count(*)
      """
    Then the result should be:
      | count(*) |
      | 100      |
    And no side effects

  Scenario: Aggregation of named paths
    Given an empty graph
    And having executed:
      """
      CREATE (a:A), (b:B), (c:C), (d:D), (e:E), (f:F)
      CREATE (a)-[:R]->(b)
      CREATE (c)-[:R]->(d)
      CREATE (d)-[:R]->(e)
      CREATE (e)-[:R]->(f)
      """
    When executing query:
      """
      MATCH p = (a)-[*]->(b)
      RETURN collect(nodes(p)) AS paths, length(p) AS l
      ORDER BY l
      """
    Then the result should be, in order:
      | paths                                                    | l |
      | [[(:A), (:B)], [(:C), (:D)], [(:D), (:E)], [(:E), (:F)]] | 1 |
      | [[(:C), (:D), (:E)], [(:D), (:E), (:F)]]                 | 2 |
      | [[(:C), (:D), (:E), (:F)]]                               | 3 |
    And no side effects

  Scenario: Aggregation with `min()`
    Given an empty graph
    And having executed:
      """
      CREATE (a:T {name: 'a'}), (b:T {name: 'b'}), (c:T {name: 'c'})
      CREATE (a)-[:R]->(b)
      CREATE (a)-[:R]->(c)
      CREATE (c)-[:R]->(b)
      """
    When executing query:
      """
      MATCH p = (a:T {name: 'a'})-[:R*]->(other:T)
      WHERE other <> a
      WITH a, other, min(length(p)) AS len
      RETURN a.name AS name, collect(other.name) AS others, len
      """
    Then the result should be (ignoring element order for lists):
      | name | others     | len |
      | 'a'  | ['c', 'b'] | 1   |
    And no side effects

  Scenario: Handle subexpression in aggregation also occurring as standalone expression with nested aggregation in a literal map
    Given an empty graph
    And having executed:
      """
      CREATE (:A), (:B {prop: 42})
      """
    When executing query:
      """
      MATCH (a:A), (b:B)
      RETURN coalesce(a.prop, b.prop) AS foo,
        b.prop AS bar,
        {y: count(b)} AS baz
      """
    Then the result should be:
      | foo | bar | baz    |
      | 42  | 42  | {y: 1} |
    And no side effects

  Scenario: Projection during aggregation in WITH before MERGE and after WITH with predicate
    Given an empty graph
    And having executed:
      """
      CREATE (:A {prop: 42})
      """
    When executing query:
      """
      UNWIND [42] AS props
      WITH props WHERE props > 32
      WITH DISTINCT props AS p
      MERGE (a:A {prop: p})
      RETURN a.prop AS prop
      """
    Then the result should be:
      | prop |
      | 42   |
    And no side effects

  Scenario: No overflow during summation
    Given any graph
    When executing query:
      """
      UNWIND range(1000000, 2000000) AS i
      WITH i
      LIMIT 3000
      RETURN sum(i)
      """
    Then the result should be:
      | sum(i)     |
      | 3004498500 |
    And no side effects

  Scenario: Counting with loops
    Given an empty graph
    And having executed:
      """
      CREATE (a), (a)-[:R]->(a)
      """
    When executing query:
      """
      MATCH ()-[r]-()
      RETURN count(r)
      """
    Then the result should be:
      | count(r) |
      | 1        |
    And no side effects

  Scenario: `max()` should aggregate strings
    Given any graph
    When executing query:
      """
      UNWIND ['a', 'b', 'B', null, 'abc', 'abc1'] AS i
      RETURN max(i)
      """
    Then the result should be:
      | max(i) |
      | 'b'    |
    And no side effects

  Scenario: `min()` should aggregate strings
    Given any graph
    When executing query:
      """
      UNWIND ['a', 'b', 'B', null, 'abc', 'abc1'] AS i
      RETURN min(i)
      """
    Then the result should be:
      | min(i) |
      | 'B'    |
    And no side effects