module arrays

fn test_min() {
    a := [8, 2, 6, 4]
    mut ri := min(a)!
    assert ri == 2
    ri = min(a[2..])!
    assert ri == 4
    b := [f32(5.1), 3.1, 1.1, 9.1]
    mut rf := min(b)!
    assert rf == f32(1.1)
    rf = min(b[..2])!
    assert rf == f32(3.1)
    c := [u8(4), 9, 3, 1]
    mut rb := min(c)!
    assert rb == u8(1)
    rb = min(c[..3])!
    assert rb == u8(3)
}

fn test_max() {
    a := [8, 2, 6, 4]
    mut ri := max(a)!
    assert ri == 8
    ri = max(a[1..])!
    assert ri == 6
    b := [f32(5.1), 3.1, 1.1, 9.1]
    mut rf := max(b)!
    assert rf == f32(9.1)
    rf = max(b[..3])!
    assert rf == f32(5.1)
    c := [u8(4), 9, 3, 1]
    mut rb := max(c)!
    assert rb == u8(9)
    rb = max(c[2..])!
    assert rb == u8(3)
}

fn test_idx_min() {
    a := [8, 2, 6, 4]
    ri := idx_min(a)!
    assert ri == 1
    b := [f32(5.1), 3.1, 1.1, 9.1]
    rf := idx_min(b)!
    assert rf == 2
    c := [u8(4), 9, 3, 1]
    rb := idx_min(c)!
    assert rb == 3
}

fn test_idx_max() {
    a := [8, 2, 6, 4]
    ri := idx_max(a)!
    assert ri == 0
    b := [f32(5.1), 3.1, 1.1, 9.1]
    rf := idx_max(b)!
    assert rf == 3
    c := [u8(4), 9, 3, 1]
    rb := idx_max(c)!
    assert rb == 1
}

fn test_merge() {
    a := [1, 3, 5, 5, 7]
    b := [2, 4, 4, 5, 6, 8]
    c := []int{}
    d := []int{}
    assert merge[int](a, b) == [1, 2, 3, 4, 4, 5, 5, 5, 6, 7, 8]
    assert merge[int](c, d) == []
    assert merge[int](a, c) == a
    assert merge[int](d, b) == b
}

fn test_append() {
    a := [1, 3, 5, 5, 7]
    b := [2, 4, 4, 5, 6, 8]
    assert append(a, b) == [1, 3, 5, 5, 7, 2, 4, 4, 5, 6, 8]
    assert append(b, a) == [2, 4, 4, 5, 6, 8, 1, 3, 5, 5, 7]
    assert append(a, []int{}) == a
    assert append([]int{}, b) == b
}

fn test_fixed_array_assignment() {
    mut a := [2]int{}
    a[0] = 111
    a[1] = 222
    b := a
    assert b[0] == a[0]
    assert b[1] == a[1]
    mut c := [2]int{}
    c = a
    assert c[0] == a[0]
    assert c[1] == a[1]
    d := [3]int{init: 333}
    for val in d {
        assert val == 333
    }
    e := [3]string{init: 'vlang'}
    for val in e {
        assert val == 'vlang'
    }
}

fn test_array_flat_map() {
    a := ['Hello V', 'Hello World', 'V Lang']
    assert flat_map[string, string](a, fn (e string) []string {
        return e.split(' ')
    }) == ['Hello', 'V', 'Hello', 'World', 'V', 'Lang']
}

fn test_array_flat_map_indexed() {
    a := ['AB', 'CD', 'EF']
    assert flat_map_indexed[string, string](a, fn (i int, e string) []string {
        mut arr := [i.str()]
        arr << e.split('')
        return arr
    }) == ['0', 'A', 'B', '1', 'C', 'D', '2', 'E', 'F']
}

fn test_map_indexed() {
    a := [1, 2, 3]
    assert map_indexed[int, int](a, fn (i int, e int) int {
        return i + e * e
    }) == [1, 5, 11]
}

fn test_group() {
    x := [4, 5, 6]
    y := [2, 1, 3]

    z := group[int](x, y)
    assert z == [[4, 2], [5, 1], [6, 3]]
    x2 := [8, 9]
    z2 := group[int](x2, y)
    assert z2 == [[8, 2], [9, 1]]
    assert group[int](x, []int{}) == [][]int{}
}

fn test_chunk() {
    x := [1, 2, 3, 4, 5]
    y := ['a', 'b', 'c', 'd', 'e', 'f']

    z1 := chunk[int](x, 2)
    assert z1 == [[1, 2], [3, 4], [5]]
    z2 := chunk[string](y, 3)
    assert z2 == [['a', 'b', 'c'], ['d', 'e', 'f']]
    assert chunk[int]([]int{}, 2) == [][]int{}
}

fn test_chunk_while() {
    assert chunk_while([0, 9, 2, 2, 3, 2, 7, 5, 9, 5], fn (x int, y int) bool {
        return x == y
    }) == [[0], [9], [2, 2], [3], [2], [7], [5], [9], [5]]

    assert chunk_while([0, 9, 2, 2, 3, 2, 7, 5, 9, 5], fn (x int, y int) bool {
        return x <= y
    }) == [[0, 9], [2, 2, 3], [2, 7], [5, 9], [5]]

    assert chunk_while('aaaabbbcca'.runes(), fn (x rune, y rune) bool {
        return x == y
    }).map({
        it[0]: it.len
    }).str() == '[{`a`: 4}, {`b`: 3}, {`c`: 2}, {`a`: 1}]'
}

fn test_window() {
    x := [1, 2, 3, 4, 5, 6]

    assert window[int](x, size: 3) == [[1, 2, 3], [2, 3, 4], [3, 4, 5],
        [4, 5, 6]]
    assert window[int](x, size: 3, step: 2) == [[1, 2, 3], [3, 4, 5]]
    assert window[int]([]int{}, size: 2) == [][]int{}
}

/////////////////////////////
type MyAlias = i64

fn (a MyAlias) + (b MyAlias) MyAlias {
    return MyAlias(i64(a) * 10 + i64(b) * 10)
}

struct MyStruct {
    x int = 5
}

fn (a MyStruct) + (b MyStruct) MyStruct {
    return MyStruct{
        x: a.x + b.x
    }
}

fn test_sum() {
    assert sum([1, 2, 3, 4, 5]) or { 0 } == 15
    assert sum([1.0, 2.5, 3.5, 4.0]) or { 0.0 } == 11.0
    assert sum([]int{}) or { 0 } == 0
    // test summing of a struct, with an overloaded + operator:
    s := [MyStruct{
        x: 30
    }, MyStruct{
        x: 20
    }, MyStruct{
        x: 10
    }]
    assert sum(s)! == MyStruct{
        x: 60
    }
    // test summing of a number type alias with an overloaded + operator:
    assert sum([MyAlias(5), MyAlias(7), MyAlias(3)])! == MyAlias((5 * 10 + 7 * 10) * 10 + 3 * 10)
}

/////////////////////////////
fn test_reduce() {
    x := [1, 2, 3, 4, 5]

    assert reduce[int](x, fn (t1 int, t2 int) int {
        return t1 + t2
    }) or { 0 } == 15
    assert reduce[string](['H', 'e', 'l', 'l', 'o'], fn (t1 string, t2 string) string {
        return t1 + t2
    }) or { '' } == 'Hello' // For the sake please use array's join instead.
    assert reduce[int]([]int{}, fn (t1 int, t2 int) int {
        return 0
    }) or { -1 } == -1
}

fn test_reduce_indexed() {
    x := [1, 2, 3, 4, 5]
    assert reduce_indexed[int](x, fn (idx int, t1 int, t2 int) int {
        return idx + t1 + t2
    }) or { 0 } == 25
}

fn test_filter_indexed() {
    x := [0, 1, 2, 3, 4, 5]

    assert filter_indexed[int](x, fn (idx int, e int) bool {
        return idx % 2 == 0
    }) == [0, 2, 4]
}

fn test_fold() {
    x := [1, 2, 3, 4, 5]

    assert fold[int, int](x, 5, fn (r int, t int) int {
        return r + t
    }) == 20
    assert fold[string, int](['H', 'e', 'l', 'l', 'l'], 0, fn (r int, t string) int {
        return r + t[0]
    }) == 497
    assert fold[int, int]([]int{}, -1, fn (t1 int, t2 int) int {
        return 0
    }) == -1
}

fn test_fold_indexed() {
    x := [1, 2, 3, 4, 5]

    assert fold_indexed[int, int](x, 5, fn (idx int, r int, t int) int {
        return idx + r + t
    }) == 30
}

fn test_flatten() {
    x := [[1, 2, 3], [4, 5, 6]]

    assert flatten[int](x) == [1, 2, 3, 4, 5, 6]
    assert flatten[int]([[]int{}]) == []
}

fn test_group_by() {
    x := ['H', 'el', 'l', 'o ']

    assert group_by[int, string](x, fn (v string) int {
        return v.len
    }) == {
        1: ['H', 'l']
        2: ['el', 'o ']
    }
    assert group_by[int, int]([]int{}, fn (v int) int {
        return 0
    }) == map[int][]int{}
}

fn test_concat_int() {
    mut a := [1, 2, 3]
    mut b := [3, 2, 1]

    assert concat(a, ...b) == [1, 2, 3, 3, 2, 1]
}

fn test_concat_string() {
    mut a := ['1', '2', '3']
    mut b := ['3', '2', '1']

    assert concat(a, ...b) == ['1', '2', '3', '3', '2', '1']
}

fn test_binary_search() {
    a := [1, 3, 3, 4, 5, 6, 7, 8, 10]
    assert binary_search(a, 3)! == 1
    assert (binary_search(a, 0) or { -1 }) == -1
}

fn test_lower_bound() {
    a := [1, 3, 3, 4, 5, 6, 7, 8, 10]
    b := []int{}
    c := [1, 2, 3]
    assert lower_bound(a, 2)! == 3
    assert (lower_bound(b, 4) or { -1 }) == -1
    assert lower_bound(c, 3)! == 3
}

fn test_upper_bound() {
    a := [1, 3, 3, 4, 5, 6, 7, 8, 10]
    b := []int{}
    c := [1, 2, 3]
    assert upper_bound(a, 9)! == 8
    assert (upper_bound(b, 4) or { -1 }) == -1
    assert upper_bound(c, 2)! == 2
}

fn test_rotate_right() {
    mut x := [1, 2, 3, 4, 5, 6]
    rotate_right(mut x, 2)
    assert x == [5, 6, 1, 2, 3, 4]
}

fn test_rotate_right_long() {
    mut x := []u64{len: 128, init: 255}
    x[0] = 0
    x[1] = 0
    x[2] = 0
    rotate_right(mut x, 64)
    assert x.len == 128
    idx := index_of_first(x, fn (idx int, x u64) bool {
        return x == 0
    })
    assert idx == 64
    assert x[idx - 1] == 255
    assert x[idx] == 0
    assert x[idx + 1] == 0
    assert x[idx + 2] == 0
    assert x[idx + 3] == 255
}

fn test_rotate_left() {
    mut x := [1, 2, 3, 4, 5, 6]
    rotate_left(mut x, 2)
    assert x == [3, 4, 5, 6, 1, 2]
}

struct Abc {
    x u64 = 1
    y u64 = 2
    z u64 = 3
}

fn test_rotate_right_struct() {
    mut x := [Abc{1, 0, 1}, Abc{2, 0, 1}, Abc{3, 0, 1}, Abc{4, 0, 1},
        Abc{5, 0, 1}, Abc{6, 0, 1}]
    rotate_right(mut x, 2)
    assert x == [Abc{5, 0, 1}, Abc{6, 0, 1}, Abc{1, 0, 1}, Abc{2, 0, 1},
        Abc{3, 0, 1}, Abc{4, 0, 1}]
}

fn test_rotate_left_struct() {
    mut x := [Abc{1, 0, 1}, Abc{2, 0, 1}, Abc{3, 0, 1}, Abc{4, 0, 1},
        Abc{5, 0, 1}, Abc{6, 0, 1}]
    rotate_left(mut x, 2)
    assert x == [Abc{3, 0, 1}, Abc{4, 0, 1}, Abc{5, 0, 1}, Abc{6, 0, 1},
        Abc{1, 0, 1}, Abc{2, 0, 1}]
}

fn test_rotate_right_string() {
    mut x := ['x1', 'x2', 'x3', 'x4', 'x5', 'x6']
    rotate_right(mut x, 2)
    assert x == ['x5', 'x6', 'x1', 'x2', 'x3', 'x4']
}

fn test_rotate_left_string() {
    mut x := ['x1', 'x2', 'x3', 'x4', 'x5', 'x6']
    rotate_left(mut x, 2)
    assert x == ['x3', 'x4', 'x5', 'x6', 'x1', 'x2']
}

fn test_copy() {
    mut a := [1, 2, 3]
    mut b := [4, 5, 6]
    assert copy(mut b, a) == 3
    assert b == [1, 2, 3]
    // check independent copies
    b[0] = 99
    assert a[0] == 1
    // check longer src
    b << 7
    assert copy(mut a, b) == 3
    assert a == [99, 2, 3]
    // check longer dst
    assert copy(mut b, [8, 9]) == 2
    assert b == [8, 9, 3, 7]
}

fn test_can_copy_bits() {
    assert can_copy_bits[u8]()
    assert can_copy_bits[int]()
    assert can_copy_bits[voidptr]()
    assert can_copy_bits[&u8]()
    // autofree needs to intercept assign
    assert !can_copy_bits[string]()
    assert !can_copy_bits[[]int]()
    // map not copyable
    assert !can_copy_bits[map[string]int]()
}

type Str = string

fn test_alias_string_contains() {
    names := [Str('')]
    assert (Str('') in names) == true
}

struct XYZ {}

fn test_array_append_empty_struct() {
    mut names := []XYZ{cap: 2}
    names << XYZ{}
    assert (XYZ{} in names) == true

    // test fixed array
    array := [XYZ{}]!
    assert (XYZ{} in names) == true
}

fn test_index_of_first() {
    // vfmt off
    assert index_of_first([1], fn (idx int, x int) bool { return x == 0 }) == -1
    assert index_of_first([4, 5, 0, 7, 0, 9], fn (idx int, x int) bool { return x == 0 }) == 2
    assert index_of_first([4, 5, 0, 7, 0, 9], fn (idx int, x int) bool { return x == 4 }) == 0
    // vfmt on
}

fn test_index_of_last() {
    // vfmt off
    assert index_of_last([1], fn (idx int, x int) bool { return x == 0 }) == -1
    assert index_of_last([4, 5, 0, 7, 0, 9], fn (idx int, x int) bool { return x == 0 }) == 4
    assert index_of_last([4, 5, 0, 7, 0, 9], fn (idx int, x int) bool { return x == 4 }) == 0
    // vfmt on
}

fn test_map_of_indexes() {
    // vfmt off
    assert arrays.map_of_indexes([]int{}) == {}
    assert arrays.map_of_indexes([1]) == {1: [0]}
    assert arrays.map_of_indexes([1, 2, 3, 999]) == {1: [0], 2: [1], 3: [2], 999: [3]}
    assert arrays.map_of_indexes([999, 1, 2, 3]) == {1: [1], 2: [2], 3: [3], 999: [0]}
    assert arrays.map_of_indexes([1, 2, 3, 4, 4, 2, 1, 4, 4, 999]) == {1: [0, 6], 2: [1, 5], 3: [2], 4: [3, 4, 7, 8], 999: [9]}

    assert arrays.map_of_indexes([]string{}) == {}
    assert arrays.map_of_indexes(['abc']) == {'abc': [0]}
    assert arrays.map_of_indexes(['abc', 'abc']) == {'abc': [0, 1]}
    assert arrays.map_of_indexes(['abc', 'def', 'abc']) == {'abc': [0, 2], 'def': [1]}
    // vfmt on
}

fn test_map_of_counts() {
    // vfmt off
    assert map_of_counts([]int{}) == {}
    assert map_of_counts([1]) == {1: 1}
    assert map_of_counts([1, 2, 3, 999]) == {1: 1, 2: 1, 3: 1, 999: 1}
    assert map_of_counts([999, 1, 2, 3]) == {1: 1, 2: 1, 3: 1, 999: 1}
    assert map_of_counts([1, 2, 3, 4, 4, 2, 1, 4, 4, 999]) == {1: 2, 2: 2, 3: 1, 4: 4, 999: 1}

    assert map_of_counts([]string{}) == {}
    assert map_of_counts(['abc']) == {'abc': 1}
    assert map_of_counts(['abc', 'abc']) == {'abc': 2}
    assert map_of_counts(['abc', 'def', 'abc']) == {'abc': 2, 'def': 1}
    // vfmt on
}

struct FindTest {
    name string
    age  int
}

const test_structs = [FindTest{'one', 1}, FindTest{'two', 2},
    FindTest{'three', 3}, FindTest{'one', 4}]

fn test_find_first() {
    // element in array
    a := [1, 2, 3, 4, 5]
    assert find_first[int](a, fn (arr int) bool {
        return arr == 3
    })? == 3, 'find element couldnt find the right element'

    // find struct
    find_by_name := find_first(test_structs, fn (arr FindTest) bool {
        return arr.name == 'one'
    })?
    assert find_by_name == FindTest{'one', 1}

    // not found
    if _ := find_first(test_structs, fn (arr FindTest) bool {
        return arr.name == 'nothing'
    })
    {
        assert false
    } else {
        assert true
    }
}

fn test_find_last() {
    // // element in array
    a := [1, 2, 3, 4, 5]
    assert find_last[int](a, fn (arr int) bool {
        return arr == 3
    })? == 3, 'find element couldnt find the right element'

    // find struct
    find_by_name := find_last(test_structs, fn (arr FindTest) bool {
        return arr.name == 'one'
    })?
    assert find_by_name == FindTest{'one', 4}

    // not found
    if _ := find_last(test_structs, fn (arr FindTest) bool {
        return arr.name == 'nothing'
    })
    {
        assert false
    } else {
        assert true
    }
}

fn test_join_to_string() {
    assert join_to_string[FindTest](test_structs, ':', fn (it FindTest) string {
        return it.name
    }) == 'one:two:three:one'
    assert join_to_string[FindTest](test_structs, '', fn (it FindTest) string {
        return it.name
    }) == 'onetwothreeone'
    assert join_to_string[int]([]int{}, ':', fn (it int) string {
        return '1'
    }) == ''
}

fn test_partition() {
    a := [1, 2, 3, 4, 5, 6, 7, 8]
    lower, upper := partition(a, fn (it int) bool {
        return it < 5
    })
    assert lower.len == 4
    assert upper.len == 4
    assert lower == [1, 2, 3, 4]
    assert upper == [5, 6, 7, 8]

    lower2, upper2 := partition(a, fn (it int) bool {
        return it < 1
    })
    assert lower2.len == 0
    assert upper2.len == 8
}

fn test_each() {
    a := [99, 1, 2, 3, 4, 5, 6, 7, 8, 1001]
    mut control_sum := 0
    for x in a {
        control_sum += x
    }

    each(a, fn (x int) {
        println(x)
    })
    mut sum := 0
    mut psum := &sum
    each(a, fn [mut psum] (x int) {
        unsafe {
            *psum += x
        }
    })
    assert control_sum == sum
}

fn test_each_indexed() {
    a := [99, 1, 2, 3, 4, 5, 6, 7, 8, 1001]
    mut control_sum := 0
    f := fn (idx int, x int) int {
        return (idx + 1) * 1000_000 + x
    }
    for idx, x in a {
        control_sum += f(idx, x)
    }

    each_indexed(a, fn (idx int, x int) {
        println('idx: ${idx}, x: ${x}')
    })
    mut sum := 0
    mut psum := &sum
    each_indexed(a, fn [mut psum, f] (idx int, x int) {
        unsafe {
            *psum += f(idx, x)
        }
    })
    assert control_sum == sum
}