package rules

import (
	"encoding/json"
	"fmt"
	"log"

	"git.beisel.it/florian/hostname-service/db"
)

type HostnameRule interface {
	Generate(params map[string]interface{}) (string, []byte, error)
	Insert(category string, params map[string]interface{}) (string, error)
	Update(category string, oldhostname string, params map[string]interface{}) (string, error)
}

type BaseRule struct{}

func (br *BaseRule) baseInsert(rule HostnameRule, category string, params map[string]interface{}) (string, error) {
	// Generate the hostname using the passed rule's Generate method
	hostname, paramsJSON, err := rule.Generate(params)
	if err != nil {
		return "", err
	}

	exists, err := db.HostnameExists(category, hostname)
	if err != nil {
		log.Printf("error checking existence of hostname: %v", err)
		return "", err
	}
	if exists {
		log.Printf("hostname %s does not exist in category %s", hostname, category)
		return "", fmt.Errorf("hostname-exists")
	}

	// Insert the hostname into the database
	err = db.InsertHostname(category, hostname, paramsJSON)
	if err != nil {
		log.Printf("Error inserting hostname into DB: %v", err)
		return "", err
	}

	return hostname, nil
}

// baseUpdate method for BaseRule
func (br *BaseRule) baseUpdate(rule HostnameRule, category string, oldhostname string, params map[string]interface{}) (string, error) {
	// Generate the new hostname using the passed rule's Generate method
	newHostname, paramsJSON, err := rule.Generate(params)
	if err != nil {
		return "", err
	}

	// Update the hostname in the database
	err = db.UpdateHostname(category, oldhostname, newHostname, paramsJSON)
	if err != nil {
		log.Printf("Error updating hostname in DB: %v", err)
		return "", err
	}

	return newHostname, nil
}

func StructToJSON(v interface{}) (string, error) {
	bytes, err := json.Marshal(v)
	if err != nil {
		return "", err
	}
	return string(bytes), nil
}