package models

import (
	"crypto/sha256"
	"encoding/json"
	"errors"
	"fmt"
	"sort"
	"strings"
)

type AttributeList map[string]string

type Participant struct {
	Meta

	Firstname string
	Lastname  string

	Token string

	Attributes AttributeList `csv:"Attributes"`
}

func (p *Participant) String() string {
	return fmt.Sprintf("%s %s", p.Lastname, p.Firstname)
}

func (p *Participant) GetHash() string {
	return fmt.Sprintf("%x", sha256.Sum256([]byte(strings.Join(append([]string{p.Lastname, p.Firstname}, p.AttributesToSlice()...), ""))))
}

func (p *Participant) AttributesToSlice() []string {
	result := make([]string, 0)

	for k, v := range p.Attributes {
		result = append(result, k, v)
	}

	return result
}

func (p *Participant) Marshal() ([]byte, error) {
	return json.Marshal(p)

}

func (p *Participant) Unmarshal(data []byte) error {
	return json.Unmarshal(data, p)
}

func (al AttributeList) MarshalCSV() (string, error) {
	result := convertMapToKeyValueOrderedString(al)
	return result, nil
}

func (al *AttributeList) UnmarshalCSV(csv string) error {
	if *al == nil {
		*al = make(AttributeList)
	}

	pairs := strings.Split(csv, ",")

	for _, pair := range pairs {
		attrVal := strings.Split(pair, ":")
		if len(attrVal) != 2 {
			return errors.New("Invalid input format for attribute list.")
		}

		attr := strings.TrimSpace(attrVal[0])
		val := strings.TrimSpace(attrVal[1])

		(*al)[attr] = val
	}

	return nil
}

func (al AttributeList) Get(key string) string {
	return al[key]
}

func (al AttributeList) String() string {
	result := make([]string, 0)
	for k, v := range al {
		result = append(result, fmt.Sprintf("%s: %s", k, v))
	}
	return strings.Join(result, ",")
}

func convertMapToKeyValueOrderedString(m map[string]string) string {
	keys := make([]string, 0, len(m))
	for key := range m {
		keys = append(keys, key)
	}

	sort.Strings(keys)

	var result strings.Builder
	for _, key := range keys {
		result.WriteString(key)
		result.WriteString(":")
		result.WriteString(m[key])
		result.WriteString(",")
	}

	return strings.TrimSuffix(result.String(), ",")
}