package yqlib

import (
	"fmt"
	"strconv"
	"strings"

	yaml "github.com/goccy/go-yaml"
	"github.com/goccy/go-yaml/ast"
	goccyToken "github.com/goccy/go-yaml/token"
)

func (o *CandidateNode) goccyDecodeIntoChild(childNode ast.Node, cm yaml.CommentMap, anchorMap map[string]*CandidateNode) (*CandidateNode, error) {
	newChild := o.CreateChild()

	err := newChild.UnmarshalGoccyYAML(childNode, cm, anchorMap)
	return newChild, err
}

func (o *CandidateNode) UnmarshalGoccyYAML(node ast.Node, cm yaml.CommentMap, anchorMap map[string]*CandidateNode) error {
	log.Debugf("UnmarshalYAML %v", node)
	log.Debugf("UnmarshalYAML %v", node.Type().String())
	log.Debugf("UnmarshalYAML Node Value: %v", node.String())
	log.Debugf("UnmarshalYAML Node GetComment: %v", node.GetComment())

	if node.GetComment() != nil {
		commentMapComments := cm[node.GetPath()]
		for _, comment := range node.GetComment().Comments {
			// need to use the comment map to find the position :/
			log.Debugf("%v has a comment of [%v]", node.GetPath(), comment.Token.Value)
			for _, commentMapComment := range commentMapComments {
				commentMapValue := strings.Join(commentMapComment.Texts, "\n")
				if commentMapValue == comment.Token.Value {
					log.Debug("found a matching entry in comment map")
					// we found the comment in the comment map,
					// now we can process the position
					switch commentMapComment.Position {
					case yaml.CommentHeadPosition:
						o.HeadComment = comment.String()
						log.Debug("its a head comment %v", comment.String())
					case yaml.CommentLinePosition:
						o.LineComment = comment.String()
						log.Debug("its a line comment %v", comment.String())
					case yaml.CommentFootPosition:
						o.FootComment = comment.String()
						log.Debug("its a foot comment %v", comment.String())
					}
				}
			}

		}
	}

	o.Value = node.String()
	o.Line = node.GetToken().Position.Line
	o.Column = node.GetToken().Position.Column

	switch node.Type() {
	case ast.IntegerType:
		o.Kind = ScalarNode
		o.Tag = "!!int"
	case ast.FloatType:
		o.Kind = ScalarNode
		o.Tag = "!!float"
	case ast.BoolType:
		o.Kind = ScalarNode
		o.Tag = "!!bool"
	case ast.NullType:
		log.Debugf("its a null type with value %v", node.GetToken().Value)
		o.Kind = ScalarNode
		o.Tag = "!!null"
		o.Value = node.GetToken().Value
	case ast.StringType:
		o.Kind = ScalarNode
		o.Tag = "!!str"
		switch node.GetToken().Type {
		case goccyToken.SingleQuoteType:
			o.Style = SingleQuotedStyle
		case goccyToken.DoubleQuoteType:
			o.Style = DoubleQuotedStyle
		}
		o.Value = node.(*ast.StringNode).Value
		log.Debugf("string value %v", node.(*ast.StringNode).Value)
	case ast.LiteralType:
		o.Kind = ScalarNode
		o.Tag = "!!str"
		o.Style = LiteralStyle
		astLiteral := node.(*ast.LiteralNode)
		log.Debugf("astLiteral.Start.Type %v", astLiteral.Start.Type)
		if astLiteral.Start.Type == goccyToken.FoldedType {
			log.Debugf("folded Type %v", astLiteral.Start.Type)
			o.Style = FoldedStyle
		}
		log.Debug("start value: %v ", node.(*ast.LiteralNode).Start.Value)
		log.Debug("start value: %v ", node.(*ast.LiteralNode).Start.Type)
		// TODO: here I could put the original value with line breaks
		// to solve the multiline > problem
		o.Value = astLiteral.Value.Value
	case ast.TagType:
		if err := o.UnmarshalGoccyYAML(node.(*ast.TagNode).Value, cm, anchorMap); err != nil {
			return err
		}
		o.Tag = node.(*ast.TagNode).Start.Value
	case ast.MappingType:
		log.Debugf("UnmarshalYAML -  a mapping node")
		o.Kind = MappingNode
		o.Tag = "!!map"

		mappingNode := node.(*ast.MappingNode)
		if mappingNode.IsFlowStyle {
			o.Style = FlowStyle
		}
		for _, mappingValueNode := range mappingNode.Values {
			err := o.goccyProcessMappingValueNode(mappingValueNode, cm, anchorMap)
			if err != nil {
				return ast.ErrInvalidAnchorName
			}
		}
		if mappingNode.FootComment != nil {
			log.Debugf("mapping node has a foot comment of: %v", mappingNode.FootComment)
			o.FootComment = mappingNode.FootComment.String()
		}
	case ast.MappingValueType:
		log.Debugf("UnmarshalYAML -  a mapping node")
		o.Kind = MappingNode
		o.Tag = "!!map"
		mappingValueNode := node.(*ast.MappingValueNode)
		err := o.goccyProcessMappingValueNode(mappingValueNode, cm, anchorMap)
		if err != nil {
			return ast.ErrInvalidAnchorName
		}
	case ast.SequenceType:
		log.Debugf("UnmarshalYAML -  a sequence node")
		o.Kind = SequenceNode
		o.Tag = "!!seq"
		sequenceNode := node.(*ast.SequenceNode)
		if sequenceNode.IsFlowStyle {
			o.Style = FlowStyle
		}
		astSeq := sequenceNode.Values
		o.Content = make([]*CandidateNode, len(astSeq))
		for i := 0; i < len(astSeq); i++ {
			keyNode := o.CreateChild()
			keyNode.IsMapKey = true
			keyNode.Tag = "!!int"
			keyNode.Kind = ScalarNode
			keyNode.Value = fmt.Sprintf("%v", i)

			valueNode, err := o.goccyDecodeIntoChild(astSeq[i], cm, anchorMap)
			if err != nil {
				return err
			}

			valueNode.Key = keyNode
			o.Content[i] = valueNode
		}
	case ast.AnchorType:
		log.Debugf("UnmarshalYAML -  an anchor node")
		anchorNode := node.(*ast.AnchorNode)
		err := o.UnmarshalGoccyYAML(anchorNode.Value, cm, anchorMap)
		if err != nil {
			return err
		}
		o.Anchor = anchorNode.Name.String()
		anchorMap[o.Anchor] = o

	case ast.AliasType:
		log.Debugf("UnmarshalYAML -  an alias node")
		aliasNode := node.(*ast.AliasNode)
		o.Kind = AliasNode
		o.Value = aliasNode.Value.String()
		o.Alias = anchorMap[o.Value]

	case ast.MergeKeyType:
		log.Debugf("UnmarshalYAML -  a merge key")
		o.Kind = ScalarNode
		o.Tag = "!!merge" // note - I should be able to get rid of this.
		o.Value = "<<"

	default:
		log.Debugf("UnmarshalYAML -  no idea of the type!!\n%v: %v", node.Type(), node.String())
	}
	log.Debugf("KIND: %v", o.Kind)
	return nil
}

func (o *CandidateNode) goccyProcessMappingValueNode(mappingEntry *ast.MappingValueNode, cm yaml.CommentMap, anchorMap map[string]*CandidateNode) error {
	log.Debug("UnmarshalYAML MAP KEY entry %v", mappingEntry.Key)

	// AddKeyValueFirst because it clones the nodes, and we want to have the real refs when Unmarshalling
	// particularly for the anchorMap
	keyNode, valueNode := o.AddKeyValueChild(&CandidateNode{}, &CandidateNode{})

	if err := keyNode.UnmarshalGoccyYAML(mappingEntry.Key, cm, anchorMap); err != nil {
		return err
	}

	log.Debug("UnmarshalYAML MAP VALUE entry %v", mappingEntry.Value)
	if err := valueNode.UnmarshalGoccyYAML(mappingEntry.Value, cm, anchorMap); err != nil {
		return err
	}

	if mappingEntry.FootComment != nil {
		valueNode.FootComment = mappingEntry.FootComment.String()
	}

	return nil
}

func (o *CandidateNode) MarshalGoccyYAML() (ast.Node, error) {
	marshaller := &goccyMarshaller{}
	return marshaller.Marshal("$", o)
}

type goccyMarshaller struct {
	currentToken *goccyToken.Token
}

func (m *goccyMarshaller) PushToken(t *goccyToken.Token) *goccyToken.Token {
	if m.currentToken == nil {
		m.currentToken = t
		return m.currentToken
	}

	m.currentToken.Next = t
	t.Prev = m.currentToken
	m.currentToken = t

	return m.currentToken
}

func (m *goccyMarshaller) Marshal(path string, o *CandidateNode) (ast.Node, error) {
	var node ast.Node
	var err error
	switch o.Kind {
	case AliasNode:
		node, err = m.marshalAlias(path, o)
		if err != nil {
			return nil, err
		}
	case ScalarNode:
		node, err = m.marshalScalar(path, o)
		if err != nil {
			return nil, err
		}
	case SequenceNode:
		node, err = m.marshalSequence(path, o)
		if err != nil {
			return nil, err
		}
	case MappingNode:
		node, err = m.marshalMapping(path, o)
	}

	// TODO: Fix Tag and Anchor tokens
	if o.Tag != "" && !strings.HasPrefix(o.Tag, "!!") {
		tag := ast.Tag(goccyToken.Tag(o.Tag, o.Tag, &goccyToken.Position{}))
		tag.Value = node
		node = tag
	}

	if o.Anchor != "" {
		anc := ast.Anchor(goccyToken.Anchor(o.Anchor, &goccyToken.Position{}))
		anc.Value = node
		node = anc
	}

	node.SetPath(path)

	return node, nil
}

func (_ *goccyMarshaller) getPosition(o *CandidateNode) *goccyToken.Position {
	return &goccyToken.Position{
		Line:   o.Line,
		Column: o.Column,
	}
}

func (m *goccyMarshaller) marshalAlias(path string, o *CandidateNode) (ast.Node, error) {
	t := m.PushToken(goccyToken.Alias(o.Value, m.getPosition(o)))
	var value ast.Node
	var err error
	value, err = m.Marshal(path, o.Content[0])
	if err != nil {
		return nil, err
	}

	alias := ast.Alias(t)
	alias.Value = value
	return alias, nil
}

func (m *goccyMarshaller) marshalSequence(path string, o *CandidateNode) (ast.Node, error) {
	isFlowStyle := o.Style == FlowStyle
	seq := ast.Sequence(
		nil,
		isFlowStyle,
	)

	if isFlowStyle {
		seq.Start = m.PushToken(goccyToken.SequenceStart("[", &goccyToken.Position{}))
	}

	var err error
	values := make([]ast.Node, len(o.Content))
	for i, content := range o.Content {
		if !isFlowStyle {
			entryToken := goccyToken.SequenceEntry("-", &goccyToken.Position{Line: content.Line, Column: o.Column})
			m.PushToken(entryToken)
			if seq.Start == nil {
				seq.Start = entryToken
			}
		}

		values[i], err = m.Marshal(path+"["+strconv.Itoa(i)+"]", content)
		if err != nil {
			return nil, err
		}

		if isFlowStyle && i < len(o.Content)-1 {
			m.PushToken(goccyToken.CollectEntry(",", &goccyToken.Position{}))
		}
	}

	if isFlowStyle {
		seq.End = m.PushToken(goccyToken.SequenceEnd("]", &goccyToken.Position{}))
	}

	seq.Values = values
	seq.ValueHeadComments = []*ast.CommentGroupNode{ast.CommentGroup([]*goccyToken.Token{goccyToken.Comment(o.HeadComment, o.HeadComment, &goccyToken.Position{})})}
	if o.FootComment != "" {
		seq.FootComment = goccyMarshalFootComment(o.FootComment)
	}

	return seq, nil
}

func (m *goccyMarshaller) marshalMapping(path string, o *CandidateNode) (ast.Node, error) {
	isFlowStyle := o.Style == FlowStyle
	mapping := ast.Mapping(nil, isFlowStyle)

	if isFlowStyle {
		mapping.Start = m.PushToken(goccyToken.MappingStart("{", &goccyToken.Position{}))
	}

	values := make([]*ast.MappingValueNode, len(o.Content)/2)
	var err error
	for i := 0; i < len(o.Content); i += 2 {
		var childNode *ast.MappingValueNode
		childNode, err = m.marshalMappingValueNode(path, o, o.Content[i], o.Content[i+1])
		if err != nil {
			return nil, err
		}

		if o.Content[i].FootComment != "" {
			childNode.FootComment = goccyMarshalFootComment(o.Content[i].FootComment)
		}

		values[i/2] = childNode
		if isFlowStyle && i < len(o.Content)/2-1 {
			m.PushToken(goccyToken.CollectEntry(",", &goccyToken.Position{}))
		}
	}

	mapping.Values = values

	if !isFlowStyle && len(values) > 0 {
		mapping.Start = values[0].Start
	}

	if isFlowStyle {
		mapping.End = m.PushToken(goccyToken.MappingEnd("}", &goccyToken.Position{}))
	}

	if o.FootComment != "" {
		mapping.FootComment = goccyMarshalFootComment(o.FootComment)
	}

	return mapping, nil
}

func (m *goccyMarshaller) marshalMappingValueNode(path string, entryNode, keyNode, valueNode *CandidateNode) (*ast.MappingValueNode, error) {
	var key ast.MapKeyNode
	var err error
	key, err = m.marshalMapKeyNode(path, keyNode)
	if err != nil {
		return nil, err
	}

	separatorToken := m.PushToken(goccyToken.MappingValue(m.getPosition(entryNode)))

	value, err := m.Marshal(key.GetPath(), valueNode)
	if err != nil {
		return nil, err
	}

	childNode := ast.MappingValue(
		separatorToken,
		key,
		value,
	)
	childNode.SetPath(key.GetPath())

	return childNode, nil
}

func goccyMarshalFootComment(comment string) *ast.CommentGroupNode {
	// TODO: Fix Tokens
	return ast.CommentGroup([]*goccyToken.Token{goccyToken.Comment(comment, comment, &goccyToken.Position{})})
}

func (m *goccyMarshaller) marshalMapKeyNode(path string, o *CandidateNode) (ast.MapKeyNode, error) {
	if o.Kind != ScalarNode {
		return nil, fmt.Errorf("cannot unmarshal non-scalar node to MapKeyNode")
	}

	key, err := m.marshalScalar(path, o)
	if err != nil {
		return nil, err
	}
	key.SetPath(path + "." + key.String())

	return key, nil
}

func (m *goccyMarshaller) marshalScalar(path string, o *CandidateNode) (ast.ScalarNode, error) {
	v, err := o.GetValueRep()
	if err != nil {
		return nil, err
	}

	scalarToken := m.PushToken(goccyToken.Literal(o.Value, o.Value, m.getPosition(o)))

	if v == nil {
		n := ast.Null(scalarToken)
		n.SetPath(path)
		return n, nil
	}

	var n ast.ScalarNode
	switch v.(type) {
	case float64:
		n = ast.Float(scalarToken)
	case int64:
		n = ast.Integer(scalarToken)
	case bool:
		n = ast.Bool(scalarToken)
	case string:
		n = ast.String(scalarToken)
	}

	if n != nil {
		n.SetPath(path)
		return n, nil
	}

	return nil, fmt.Errorf("unknown scalar value type")
}