// Copyright 2024 Matthew Rich <matthewrich.conf@gmail.com>. All rights reserved.

package folio

import (
	"context"
	"encoding/json"
	"fmt"
	"io"
	"net/url"
	"strings"
	"gopkg.in/yaml.v3"
	"decl/internal/codec"
	"decl/internal/data"
	"decl/internal/schema"
)

type ConfigKey string

// Lookup a config value using block.key identifier (E.g. system.GOOS)
func (c ConfigKey) GetValue() (value any, err error) {
	fields := strings.SplitN(string(c), ".", 2)
	if configBlock, ok := DocumentRegistry.ConfigNameMap.Get(fields[0]); ok && len(fields) > 1 {
		return configBlock.GetValue(fields[1])
	} else {
		return nil, fmt.Errorf("%w - %s", data.ErrUnknownConfigurationType, c)
	}
}

func (c ConfigKey) Get() any {
	if v, err := c.GetValue(); err == nil {
		return v
	}
	return nil
}

func (c ConfigKey) GetStringSlice() []string {
	if v, err := c.GetValue(); err == nil {
		return v.([]string)
	}
	return nil
}

type BlockType struct {
	Name string `json:"name" yaml:"name"`
	Type TypeName `json:"type" yaml:"type"`
}

type Block struct {
	Name string `json:"name" yaml:"name"`
	Type TypeName `json:"type" yaml:"type"`
	Values data.Configuration `json:"values" yaml:"values"`
	ConfigurationTypes data.TypesRegistry[data.Configuration] `json:"-" yaml:"-"`
}

func NewBlock() *Block {
	return &Block{ Type: "generic", ConfigurationTypes: DocumentRegistry.ConfigurationTypes }
}

func (b *Block) Clone() data.Block {
	return &Block {
		Type: b.Type,
		Values: b.Values.Clone(),
	}
}

func (b *Block) Load(docData []byte, f codec.Format) (err error) {
	err = f.StringDecoder(string(docData)).Decode(b)
	return
}

func (b *Block) LoadReader(r io.ReadCloser, f codec.Format) (err error) {
	err = f.Decoder(r).Decode(b)
	return
}

func (b *Block) LoadString(docData string, f codec.Format) (err error) {
	err = f.StringDecoder(docData).Decode(b)
	return
}

func (b *Block) LoadBlock(yamlBlock string) (err error) {
	return b.LoadString(yamlBlock, codec.FormatYaml)
}

func (b *Block) JSON() ([]byte, error) {
	var buf strings.Builder
	err := codec.FormatJson.Serialize(b, &buf)
	return []byte(buf.String()), err
}

func (b *Block) YAML() ([]byte, error) {
	var buf strings.Builder
	err := codec.FormatYaml.Serialize(b, &buf)
	return []byte(buf.String()), err
}

func (b *Block) PB() ([]byte, error) {
	var buf strings.Builder
	err := codec.FormatProtoBuf.Serialize(b, &buf)
	return []byte(buf.String()), err
}

func (b *Block) Validate() (err error) {
	var blockJson []byte
	if blockJson, err = b.JSON(); err == nil {
		s := schema.New(fmt.Sprintf("%s-block", b.Type), schemaFiles) // XXX wrong schemaFiles
		err = s.Validate(string(blockJson))
	}
	return
}

func (b *Block) NewConfiguration(uri *string) (err error) {
	if b.ConfigurationTypes == nil {
		panic(fmt.Errorf("Undefined type registry: unable to create new configuration %s", *uri))
	}
	if uri == nil {
		b.Values, err = b.ConfigurationTypes.New(fmt.Sprintf("%s://", b.Type))
	} else {
		b.Values, err = b.ConfigurationTypes.New(*uri)
	}
	return
}

func (b *Block) NewConfigurationFromParsedURI(uri *url.URL) (err error) {
	if uri == nil {
		b.Values, err = b.ConfigurationTypes.New(fmt.Sprintf("%s://", b.Type))
	} else {
		b.Values, err = b.ConfigurationTypes.NewFromParsedURI(uri)
	}
	return
}

func (b *Block) GetValue(key string) (any, error) {
	return b.Values.GetValue(key)
}

func (b *Block) Configuration() data.Configuration {
	return b.Values
}

func (b *Block) ConfigurationType() data.TypeName {
	return data.TypeName(b.Type)
}

func (b *Block) URI() string {
	return b.Values.URI()
}

func (b *Block) SetURI(uri string) (err error) {
	if b.Values == nil {
		if err = b.NewConfiguration(&uri); err != nil {
			return
		}
	}
	if b.Values == nil {
		return fmt.Errorf("%w - %s", data.ErrUnknownConfigurationType, uri)
	}
	b.Type = TypeName(b.Values.Type())
	_,err = b.Values.Read(context.Background())
	return
}

func (b *Block) SetParsedURI(uri data.URIParser) (err error) {
	if b.Values == nil {
		if err = b.NewConfigurationFromParsedURI(uri.URL()); err != nil {
			return
		}
	}
	if b.Values == nil {
		return fmt.Errorf("%w - %s", data.ErrUnknownConfigurationType, uri)
	}
	b.Type = TypeName(b.Values.Type())
	_,err = b.Values.Read(context.Background())
	return
}

func (b *Block) UnmarshalValue(value *BlockType) error {
	if b.ConfigurationTypes == nil {
		panic(fmt.Errorf("Undefined type registry: unable to create new configuration %s", value.Type))
	}
	b.Name = value.Name
	if value.Type == "" {
		b.Type = "generic"
	} else {
		b.Type = value.Type
	}

	newConfig, configErr := b.ConfigurationTypes.New(fmt.Sprintf("%s://", b.Type))
	if configErr != nil {
		return configErr
	}
	b.Values = newConfig
	return nil
}

func (b *Block) UnmarshalYAML(value *yaml.Node) error {
	if b.ConfigurationTypes == nil {
		b.ConfigurationTypes = DocumentRegistry.ConfigurationTypes
	}
	t := &BlockType{}
	if unmarshalConfigurationTypeErr := value.Decode(t); unmarshalConfigurationTypeErr != nil {
		return unmarshalConfigurationTypeErr
	}

	if err := b.UnmarshalValue(t); err != nil {
		return err
	}

	configurationVals := struct {
		Values yaml.Node `json:"values"`
	}{}
	if unmarshalValuesErr := value.Decode(&configurationVals); unmarshalValuesErr != nil {
		return unmarshalValuesErr
	}
	if unmarshalConfigurationErr := configurationVals.Values.Decode(b.Values); unmarshalConfigurationErr != nil {
		return unmarshalConfigurationErr
	}
	_, readErr := b.Values.Read(context.Background())
	return readErr
}

func (b *Block) UnmarshalJSON(jsonData []byte) error {
	if b.ConfigurationTypes == nil {
		b.ConfigurationTypes = DocumentRegistry.ConfigurationTypes
	}
	t := &BlockType{}
	if unmarshalConfigurationTypeErr := json.Unmarshal(jsonData, t); unmarshalConfigurationTypeErr != nil {
		return unmarshalConfigurationTypeErr
	}

	if err := b.UnmarshalValue(t); err != nil {
		return err
	}

	configurationVals := struct {
		Values data.Configuration `json:"values"`
	}{Values: b.Values}
	if unmarshalValuesErr := json.Unmarshal(jsonData, &configurationVals); unmarshalValuesErr != nil {
		return unmarshalValuesErr
	}
	_, readErr := b.Values.Read(context.Background())
	return readErr
}