package configuration

import (
	"errors"
	"fmt"
	"net"
	"net/url"
)

// Application configuration which is parsed from config.yaml.
type Configuration struct {
	LogLevel int              `yaml:"logLevel"` // Application log level.
	Host     string           `yaml:"host"`     // Host address that application will bind to.
	Port     uint16           `yaml:"port"`     // Host port which application will listen for HTTP requests.
	PVE      PveConfiguration `yaml:"proxmox"`  // PVE configuration.
}

// PVE token configuration.
type PveTokenConfiguration struct {
	TokenId string `yaml:"tokenId"` // Token ID from PVE API key management.
	Secret  string `yaml:"secret"`  // Secret from PVE API key management.
}

// MetricsConfiguration represents the metrics configuration.
type PveMetricsConfiguration struct {
	ClusterState bool `yaml:"clusterState"` // Enables cluster state metrics collection.
	LXC          bool `yaml:"lxc"`          // Enables LXC container metrics collection.
	QEMU         bool `yaml:"qemu"`         // Enable QEMU virtual machine metrics collection.
	Disk         bool `yaml:"disk"`         // Enable physical disk metrics collection.
	Storage      bool `yaml:"storage"`      // Enable node storage metrics collection.
	NodeStatus   bool `yaml:"nodeStatus"`   // Enable node status metrics collection.
	Subscription bool `yaml:"subscription"` // Enable node subscription detail collection.
	SDN          bool `yaml:"sdn"`          // Enable node software defined network state collection.
}

// PVE configuration.
type PveConfiguration struct {
	Token    PveTokenConfiguration   `yaml:"token"`    // PVE token.
	Hosts    []string                `yaml:"hosts"`    // PVE hosts.
	Interval int                     `yaml:"interval"` // PVE scrape interval.
	Metrics  PveMetricsConfiguration `yaml:"metrics"`  // PVE metrics.
}

// Validate configuration and check for mandaotry field.
func (c *Configuration) Validate() error {
	// Validate host IP
	if net.ParseIP(c.Host) == nil {
		return fmt.Errorf("Host is not a valid IP address: %s", c.Host)
	}

	// Validate PVE hosts
	if len(c.PVE.Hosts) == 0 {
		return errors.New("PVE hosts cannot be empty.")
	}

	for _, host := range c.PVE.Hosts {
		u, err := url.Parse(host)
		if err != nil {
			return fmt.Errorf("PVE host '%s' is not valid URL. Error: %s", host, err)
		}

		if !(u.Scheme == "http" || u.Scheme == "https") {
			return fmt.Errorf("PVE host '%s' must be protocol type of HTTP or HTTPS.", host)
		}
	}

	// Validate PVE token
	if c.PVE.Token.TokenId == "" {
		return errors.New("PVE tokenId cannot be empty")
	}

	if c.PVE.Token.Secret == "" {
		return errors.New("PVE secret cannot be empty")
	}

	return nil
}