// LoadProvidersHcl recurses into the given HCL object and turns
// it into a mapping of provider configs.
func loadProvidersHcl(os *hclobj.Object) ([]*ProviderConfig, error) {
	var objects []*hclobj.Object

	// Iterate over all the "provider" blocks and get the keys along with
	// their raw configuration objects. We'll parse those later.
	for _, o1 := range os.Elem(false) {
		for _, o2 := range o1.Elem(true) {
			objects = append(objects, o2)
		}
	}

	if len(objects) == 0 {
		return nil, nil
	}

	// Go through each object and turn it into an actual result.
	result := make([]*ProviderConfig, 0, len(objects))
	for _, o := range objects {
		var config map[string]interface{}

		if err := hcl.DecodeObject(&config, o); err != nil {
			return nil, err
		}

		delete(config, "alias")

		rawConfig, err := NewRawConfig(config)
		if err != nil {
			return nil, fmt.Errorf(
				"Error reading config for provider config %s: %s",
				o.Key,
				err)
		}

		// If we have an alias field, then add those in
		var alias string
		if a := o.Get("alias", false); a != nil {
			err := hcl.DecodeObject(&alias, a)
			if err != nil {
				return nil, fmt.Errorf(
					"Error reading alias for provider[%s]: %s",
					o.Key,
					err)
			}
		}

		result = append(result, &ProviderConfig{
			Name:      o.Key,
			Alias:     alias,
			RawConfig: rawConfig,
		})
	}

	return result, nil
}

func (d *decoder) decodeSlice(name string, o *hcl.Object, result reflect.Value) error {
	// If we have an interface, then we can address the interface,
	// but not the slice itself, so get the element but set the interface
	set := result
	if result.Kind() == reflect.Interface {
		result = result.Elem()
	}

	// Create the slice if it isn't nil
	resultType := result.Type()
	resultElemType := resultType.Elem()
	if result.IsNil() {
		resultSliceType := reflect.SliceOf(resultElemType)
		result = reflect.MakeSlice(
			resultSliceType, 0, 0)
	}

	// Determine how we're doing this
	expand := true
	switch o.Type {
	case hcl.ValueTypeObject:
		expand = false
	default:
		// Array or anything else: we expand values and take it all
	}

	i := 0
	for _, o := range o.Elem(expand) {
		fieldName := fmt.Sprintf("%s[%d]", name, i)

		// Decode
		val := reflect.Indirect(reflect.New(resultElemType))
		if err := d.decode(fieldName, o, val); err != nil {
			return err
		}

		// Append it onto the slice
		result = reflect.Append(result, val)

		i += 1
	}

	set.Set(result)
	return nil
}

// LoadOutputsHcl recurses into the given HCL object and turns
// it into a mapping of outputs.
func loadOutputsHcl(os *hclobj.Object) ([]*Output, error) {
	objects := make(map[string]*hclobj.Object)

	// Iterate over all the "output" blocks and get the keys along with
	// their raw configuration objects. We'll parse those later.
	for _, o1 := range os.Elem(false) {
		for _, o2 := range o1.Elem(true) {
			objects[o2.Key] = o2
		}
	}

	if len(objects) == 0 {
		return nil, nil
	}

	// Go through each object and turn it into an actual result.
	result := make([]*Output, 0, len(objects))
	for n, o := range objects {
		var config map[string]interface{}

		if err := hcl.DecodeObject(&config, o); err != nil {
			return nil, err
		}

		rawConfig, err := NewRawConfig(config)
		if err != nil {
			return nil, fmt.Errorf(
				"Error reading config for output %s: %s",
				n,
				err)
		}

		result = append(result, &Output{
			Name:      n,
			RawConfig: rawConfig,
		})
	}

	return result, nil
}

func (d *decoder) decodeStruct(name string, o *hcl.Object, result reflect.Value) error {
	if o.Type != hcl.ValueTypeObject {
		return fmt.Errorf("%s: not an object type for struct (%v)", name, o.Type)
	}

	// This slice will keep track of all the structs we'll be decoding.
	// There can be more than one struct if there are embedded structs
	// that are squashed.
	structs := make([]reflect.Value, 1, 5)
	structs[0] = result

	// Compile the list of all the fields that we're going to be decoding
	// from all the structs.
	fields := make(map[*reflect.StructField]reflect.Value)
	for len(structs) > 0 {
		structVal := structs[0]
		structs = structs[1:]

		structType := structVal.Type()
		for i := 0; i < structType.NumField(); i++ {
			fieldType := structType.Field(i)

			if fieldType.Anonymous {
				fieldKind := fieldType.Type.Kind()
				if fieldKind != reflect.Struct {
					return fmt.Errorf(
						"%s: unsupported type to struct: %s",
						fieldType.Name, fieldKind)
				}

				// We have an embedded field. We "squash" the fields down
				// if specified in the tag.
				squash := false
				tagParts := strings.Split(fieldType.Tag.Get(tagName), ",")
				for _, tag := range tagParts[1:] {
					if tag == "squash" {
						squash = true
						break
					}
				}

				if squash {
					structs = append(
						structs, result.FieldByName(fieldType.Name))
					continue
				}
			}

			// Normal struct field, store it away
			fields[&fieldType] = structVal.Field(i)
		}
	}

	usedKeys := make(map[string]struct{})
	decodedFields := make([]string, 0, len(fields))
	decodedFieldsVal := make([]reflect.Value, 0)
	unusedKeysVal := make([]reflect.Value, 0)
	for fieldType, field := range fields {
		if !field.IsValid() {
			// This should never happen
			panic("field is not valid")
		}

		// If we can't set the field, then it is unexported or something,
		// and we just continue onwards.
		if !field.CanSet() {
			continue
		}

		fieldName := fieldType.Name

		// This is whether or not we expand the object into its children
		// later.
		expand := false

		tagValue := fieldType.Tag.Get(tagName)
		tagParts := strings.SplitN(tagValue, ",", 2)
		if len(tagParts) >= 2 {
			switch tagParts[1] {
			case "expand":
				expand = true
			case "decodedFields":
				decodedFieldsVal = append(decodedFieldsVal, field)
				continue
			case "key":
				field.SetString(o.Key)
				continue
			case "unusedKeys":
				unusedKeysVal = append(unusedKeysVal, field)
				continue
			}
		}

		if tagParts[0] != "" {
			fieldName = tagParts[0]
		}

		// Find the element matching this name
		obj := o.Get(fieldName, true)
		if obj == nil {
//.........这里部分代码省略.........

func (d *decoder) decodeMap(name string, o *hcl.Object, result reflect.Value) error {
	if o.Type != hcl.ValueTypeObject {
		return fmt.Errorf("%s: not an object type for map (%v)", name, o.Type)
	}

	// If we have an interface, then we can address the interface,
	// but not the slice itself, so get the element but set the interface
	set := result
	if result.Kind() == reflect.Interface {
		result = result.Elem()
	}

	resultType := result.Type()
	resultElemType := resultType.Elem()
	resultKeyType := resultType.Key()
	if resultKeyType.Kind() != reflect.String {
		return fmt.Errorf(
			"%s: map must have string keys", name)
	}

	// Make a map if it is nil
	resultMap := result
	if result.IsNil() {
		resultMap = reflect.MakeMap(
			reflect.MapOf(resultKeyType, resultElemType))
	}

	// Go through each element and decode it.
	for _, o := range o.Elem(false) {
		if o.Value == nil {
			continue
		}

		for _, o := range o.Elem(true) {
			// Make the field name
			fieldName := fmt.Sprintf("%s.%s", name, o.Key)

			// Get the key/value as reflection values
			key := reflect.ValueOf(o.Key)
			val := reflect.Indirect(reflect.New(resultElemType))

			// If we have a pre-existing value in the map, use that
			oldVal := resultMap.MapIndex(key)
			if oldVal.IsValid() {
				val.Set(oldVal)
			}

			// Decode!
			if err := d.decode(fieldName, o, val); err != nil {
				return err
			}

			// Set the value on the map
			resultMap.SetMapIndex(key, val)
		}
	}

	// Set the final map if we can
	set.Set(resultMap)
	return nil
}

func (d *decoder) decodeInterface(name string, o *hcl.Object, result reflect.Value) error {
	var set reflect.Value
	redecode := true

	switch o.Type {
	case hcl.ValueTypeObject:
		// If we're at the root or we're directly within a slice, then we
		// decode objects into map[string]interface{}, otherwise we decode
		// them into lists.
		if len(d.stack) == 0 || d.stack[len(d.stack)-1] == reflect.Slice {
			var temp map[string]interface{}
			tempVal := reflect.ValueOf(temp)
			result := reflect.MakeMap(
				reflect.MapOf(
					reflect.TypeOf(""),
					tempVal.Type().Elem()))

			set = result
		} else {
			var temp []map[string]interface{}
			tempVal := reflect.ValueOf(temp)
			result := reflect.MakeSlice(
				reflect.SliceOf(tempVal.Type().Elem()), 0, int(o.Len()))
			set = result
		}
	case hcl.ValueTypeList:
		var temp []interface{}
		tempVal := reflect.ValueOf(temp)
		result := reflect.MakeSlice(
			reflect.SliceOf(tempVal.Type().Elem()), 0, 0)
		set = result
	case hcl.ValueTypeBool:
		var result bool
		set = reflect.Indirect(reflect.New(reflect.TypeOf(result)))
	case hcl.ValueTypeFloat:
		var result float64
		set = reflect.Indirect(reflect.New(reflect.TypeOf(result)))
	case hcl.ValueTypeInt:
		var result int
		set = reflect.Indirect(reflect.New(reflect.TypeOf(result)))
	case hcl.ValueTypeString:
		set = reflect.Indirect(reflect.New(reflect.TypeOf("")))
	default:
		return fmt.Errorf(
			"%s: cannot decode into interface: %T",
			name, o)
	}

	// Set the result to what its supposed to be, then reset
	// result so we don't reflect into this method anymore.
	result.Set(set)

	if redecode {
		// Revisit the node so that we can use the newly instantiated
		// thing and populate it.
		if err := d.decode(name, o, result); err != nil {
			return err
		}
	}

	return nil
}

func loadProvisionersHcl(os *hclobj.Object, connInfo map[string]interface{}) ([]*Provisioner, error) {
	pos := make([]*hclobj.Object, 0, int(os.Len()))

	// Accumulate all the actual provisioner configuration objects. We
	// have to iterate twice here:
	//
	//  1. The first iteration is of the list of `provisioner` blocks.
	//  2. The second iteration is of the dictionary within the
	//      provisioner which will have only one element which is the
	//      type of provisioner to use along with tis config.
	//
	// In JSON it looks kind of like this:
	//
	//   [
	//     {
	//       "shell": {
	//         ...
	//       }
	//     }
	//   ]
	//
	for _, o1 := range os.Elem(false) {
		for _, o2 := range o1.Elem(true) {

			switch o1.Type {
			case hclobj.ValueTypeList:
				for _, o3 := range o2.Elem(true) {
					pos = append(pos, o3)
				}
			case hclobj.ValueTypeObject:
				pos = append(pos, o2)
			}
		}
	}

	// Short-circuit if there are no items
	if len(pos) == 0 {
		return nil, nil
	}

	result := make([]*Provisioner, 0, len(pos))
	for _, po := range pos {
		var config map[string]interface{}
		if err := hcl.DecodeObject(&config, po); err != nil {
			return nil, err
		}

		// Delete the "connection" section, handle seperately
		delete(config, "connection")

		rawConfig, err := NewRawConfig(config)
		if err != nil {
			return nil, err
		}

		// Check if we have a provisioner-level connection
		// block that overrides the resource-level
		var subConnInfo map[string]interface{}
		if o := po.Get("connection", false); o != nil {
			err := hcl.DecodeObject(&subConnInfo, o)
			if err != nil {
				return nil, err
			}
		}

		// Inherit from the resource connInfo any keys
		// that are not explicitly overriden.
		if connInfo != nil && subConnInfo != nil {
			for k, v := range connInfo {
				if _, ok := subConnInfo[k]; !ok {
					subConnInfo[k] = v
				}
			}
		} else if subConnInfo == nil {
			subConnInfo = connInfo
		}

		// Parse the connInfo
		connRaw, err := NewRawConfig(subConnInfo)
		if err != nil {
			return nil, err
		}

		result = append(result, &Provisioner{
			Type:      po.Key,
			RawConfig: rawConfig,
			ConnInfo:  connRaw,
		})
	}

	return result, nil
}

// Given a handle to a HCL object, this recurses into the structure
// and pulls out a list of resources.
//
// The resulting resources may not be unique, but each resource
// represents exactly one resource definition in the HCL configuration.
// We leave it up to another pass to merge them together.
func loadResourcesHcl(os *hclobj.Object) ([]*Resource, error) {
	var allTypes []*hclobj.Object

	// HCL object iteration is really nasty. Below is likely to make
	// no sense to anyone approaching this code. Luckily, it is very heavily
	// tested. If working on a bug fix or feature, we recommend writing a
	// test first then doing whatever you want to the code below. If you
	// break it, the tests will catch it. Likewise, if you change this,
	// MAKE SURE you write a test for your change, because its fairly impossible
	// to reason about this mess.
	//
	// Functionally, what the code does below is get the libucl.Objects
	// for all the TYPES, such as "aws_security_group".
	for _, o1 := range os.Elem(false) {
		// Iterate the inner to get the list of types
		for _, o2 := range o1.Elem(true) {
			// Iterate all of this type to get _all_ the types
			for _, o3 := range o2.Elem(false) {
				allTypes = append(allTypes, o3)
			}
		}
	}

	// Where all the results will go
	var result []*Resource

	// Now go over all the types and their children in order to get
	// all of the actual resources.
	for _, t := range allTypes {
		for _, obj := range t.Elem(true) {
			k := obj.Key

			var config map[string]interface{}
			if err := hcl.DecodeObject(&config, obj); err != nil {
				return nil, fmt.Errorf(
					"Error reading config for %s[%s]: %s",
					t.Key,
					k,
					err)
			}

			// Remove the fields we handle specially
			delete(config, "connection")
			delete(config, "count")
			delete(config, "depends_on")
			delete(config, "provisioner")
			delete(config, "provider")
			delete(config, "lifecycle")

			rawConfig, err := NewRawConfig(config)
			if err != nil {
				return nil, fmt.Errorf(
					"Error reading config for %s[%s]: %s",
					t.Key,
					k,
					err)
			}

			// If we have a count, then figure it out
			var count string = "1"
			if o := obj.Get("count", false); o != nil {
				err = hcl.DecodeObject(&count, o)
				if err != nil {
					return nil, fmt.Errorf(
						"Error parsing count for %s[%s]: %s",
						t.Key,
						k,
						err)
				}
			}
			countConfig, err := NewRawConfig(map[string]interface{}{
				"count": count,
			})
			if err != nil {
				return nil, err
			}
			countConfig.Key = "count"

			// If we have depends fields, then add those in
			var dependsOn []string
			if o := obj.Get("depends_on", false); o != nil {
				err := hcl.DecodeObject(&dependsOn, o)
				if err != nil {
					return nil, fmt.Errorf(
						"Error reading depends_on for %s[%s]: %s",
						t.Key,
						k,
						err)
				}
			}

			// If we have connection info, then parse those out
			var connInfo map[string]interface{}
			if o := obj.Get("connection", false); o != nil {
//.........这里部分代码省略.........

// Given a handle to a HCL object, this recurses into the structure
// and pulls out a list of modules.
//
// The resulting modules may not be unique, but each module
// represents exactly one module definition in the HCL configuration.
// We leave it up to another pass to merge them together.
func loadModulesHcl(os *hclobj.Object) ([]*Module, error) {
	var allNames []*hclobj.Object

	// See loadResourcesHcl for why this exists. Don't touch this.
	for _, o1 := range os.Elem(false) {
		// Iterate the inner to get the list of types
		for _, o2 := range o1.Elem(true) {
			// Iterate all of this type to get _all_ the types
			for _, o3 := range o2.Elem(false) {
				allNames = append(allNames, o3)
			}
		}
	}

	// Where all the results will go
	var result []*Module

	// Now go over all the types and their children in order to get
	// all of the actual resources.
	for _, obj := range allNames {
		k := obj.Key

		var config map[string]interface{}
		if err := hcl.DecodeObject(&config, obj); err != nil {
			return nil, fmt.Errorf(
				"Error reading config for %s: %s",
				k,
				err)
		}

		// Remove the fields we handle specially
		delete(config, "source")

		rawConfig, err := NewRawConfig(config)
		if err != nil {
			return nil, fmt.Errorf(
				"Error reading config for %s: %s",
				k,
				err)
		}

		// If we have a count, then figure it out
		var source string
		if o := obj.Get("source", false); o != nil {
			err = hcl.DecodeObject(&source, o)
			if err != nil {
				return nil, fmt.Errorf(
					"Error parsing source for %s: %s",
					k,
					err)
			}
		}

		result = append(result, &Module{
			Name:      k,
			Source:    source,
			RawConfig: rawConfig,
		})
	}

	return result, nil
}