package scrapeconfig

import (
	"fmt"
	"gitee.com/tianmaotalk/promtail_embedded/pkg/omclient/promtail/discovery"
	"gitee.com/tianmaotalk/promtail_embedded/pkg/omclient/promtail/discovery/file"
	"gitee.com/tianmaotalk/promtail_embedded/pkg/omclient/promtail/discovery/relabel"
	"gitee.com/tianmaotalk/promtail_embedded/pkg/omclient/promtail/logentry/stages"
	"reflect"

	"github.com/prometheus/common/model"
)

// Config describes a job to scrape.
type Config struct {
	JobName                string                 `yaml:"job_name,omitempty"`
	PipelineStages         stages.PipelineStages  `yaml:"pipeline_stages,omitempty"`
	JournalConfig          *JournalTargetConfig   `yaml:"journal,omitempty"`
	RelabelConfigs         []*relabel.Config      `yaml:"relabel_configs,omitempty"`
	ServiceDiscoveryConfig ServiceDiscoveryConfig `yaml:",inline"`
}

type ServiceDiscoveryConfig struct {
	// List of static configurations
	StaticConfigs discovery.StaticConfig `yaml:"static_configs"`
	// List of file service discovery configurations.
	FileSDConfigs []*file.SDConfig `yaml:"file_sd_configs,omitempty"`
}

func (cfg ServiceDiscoveryConfig) Configs() (res discovery.Configs) {
	if x := cfg.StaticConfigs; len(x) > 0 {
		res = append(res, x)
	}
	for _, x := range cfg.FileSDConfigs {
		res = append(res, x)
	}
	return res
}

// JournalTargetConfig describes systemd journal records to scrape.
type JournalTargetConfig struct {
	// MaxAge determines the oldest relative time from process start that will
	// be read and sent to Loki. Values like 14h means no entry older than
	// 14h will be read. If unspecified, defaults to 7h.
	//
	// A relative time specified here takes precedence over the saved position;
	// if the cursor is older than the MaxAge value, it will not be used.
	MaxAge string `yaml:"max_age"`

	// JSON forces the output message of entries read from the journal to be
	// JSON. The message will contain all original fields from the source
	// journal entry.
	JSON bool `yaml:"json"`

	// Labels optionally holds labels to associate with each record coming out
	// of the journal.
	Labels model.LabelSet `yaml:"labels"`

	// Path to a directory to read journal entries from. Defaults to system path
	// if empty.
	Path string `yaml:"path"`
}

// DefaultScrapeConfig is the default Config.
var DefaultScrapeConfig = Config{
	PipelineStages: stages.PipelineStages{},
}

// HasServiceDiscoveryConfig checks to see if the service discovery used for
// file targets is non-zero.
func (c *Config) HasServiceDiscoveryConfig() bool {
	return !reflect.DeepEqual(c.ServiceDiscoveryConfig, ServiceDiscoveryConfig{})
}

// UnmarshalYAML implements the yaml.Unmarshaler interface.
func (c *Config) UnmarshalYAML(unmarshal func(interface{}) error) error {

	*c = DefaultScrapeConfig

	type plain Config
	if err := unmarshal((*plain)(c)); err != nil {
		return err
	}

	if len(c.JobName) == 0 {
		return fmt.Errorf("job_name is empty")
	}

	return nil
}