package wasm

import (
	"testing"

	"github.com/tetratelabs/wazero/internal/testing/require"
)

func TestModule_SectionElementCount(t *testing.T) {
	i32, f32 := ValueTypeI32, ValueTypeF32
	zero := uint32(0)
	empty := ConstantExpression{Opcode: OpcodeI32Const, Data: const0}

	tests := []struct {
		name     string
		input    *Module
		expected map[string]uint32
	}{
		{
			name:     "empty",
			input:    &Module{},
			expected: map[string]uint32{},
		},
		{
			name:     "NameSection",
			input:    &Module{NameSection: &NameSection{ModuleName: "simple"}},
			expected: map[string]uint32{"custom": 1},
		},
		{
			name: "TypeSection",
			input: &Module{
				TypeSection: []FunctionType{
					{},
					{Params: []ValueType{i32, i32}, Results: []ValueType{i32}},
					{Params: []ValueType{i32, i32, i32, i32}, Results: []ValueType{i32}},
				},
			},
			expected: map[string]uint32{"type": 3},
		},
		{
			name: "TypeSection and ImportSection",
			input: &Module{
				TypeSection: []FunctionType{
					{Params: []ValueType{i32, i32}, Results: []ValueType{i32}},
					{Params: []ValueType{f32, f32}, Results: []ValueType{f32}},
				},
				ImportSection: []Import{
					{
						Module: "Math", Name: "Mul",
						Type:     ExternTypeFunc,
						DescFunc: 1,
					}, {
						Module: "Math", Name: "Add",
						Type:     ExternTypeFunc,
						DescFunc: 0,
					},
				},
			},
			expected: map[string]uint32{"import": 2, "type": 2},
		},
		{
			name: "TypeSection, FunctionSection, CodeSection, ExportSection and StartSection",
			input: &Module{
				TypeSection:     []FunctionType{{}},
				FunctionSection: []Index{0},
				CodeSection: []Code{
					{Body: []byte{OpcodeLocalGet, 0, OpcodeLocalGet, 1, OpcodeI32Add, OpcodeEnd}},
				},
				ExportSection: []Export{
					{Name: "AddInt", Type: ExternTypeFunc, Index: Index(0)},
				},
				StartSection: &zero,
			},
			expected: map[string]uint32{"code": 1, "export": 1, "function": 1, "start": 1, "type": 1},
		},
		{
			name: "MemorySection and DataSection",
			input: &Module{
				MemorySection: &Memory{Min: 1},
				DataSection:   []DataSegment{{OffsetExpression: empty}},
			},
			expected: map[string]uint32{"data": 1, "memory": 1},
		},
		{
			name: "TableSection and ElementSection",
			input: &Module{
				TableSection:   []Table{{Min: 1}},
				ElementSection: []ElementSegment{{OffsetExpr: empty}},
			},
			expected: map[string]uint32{"element": 1, "table": 1},
		},
		{
			name: "TableSection (multiple tables) and ElementSection",
			input: &Module{
				TableSection:   []Table{{Min: 1}, {Min: 2}},
				ElementSection: []ElementSegment{{OffsetExpr: empty}},
			},
			expected: map[string]uint32{"element": 1, "table": 2},
		},
	}

	for _, tt := range tests {
		tc := tt

		t.Run(tc.name, func(t *testing.T) {
			actual := map[string]uint32{}
			for i := SectionID(0); i <= SectionIDData; i++ {
				if size := tc.input.SectionElementCount(i); size > 0 {
					actual[SectionIDName(i)] = size
				}
			}
			require.Equal(t, tc.expected, actual)
		})
	}
}