package repository

import (
	"database/sql"

	"github.com/ClusterCockpit/cc-backend/log"
	"github.com/ClusterCockpit/cc-backend/schema"
	sq "github.com/Masterminds/squirrel"
	"github.com/jmoiron/sqlx"
)

type JobRepository struct {
	DB *sqlx.DB
}

// Find executes a SQL query to find a specific batch job.
// The job is queried using the batch job id, the cluster name,
// and the start time of the job in UNIX epoch time seconds.
// It returns a pointer to a schema.Job data structure and an error variable.
// If the job was not found nil is returned for the job pointer.
func (r *JobRepository) Find(
	jobId int64,
	cluster string,
	startTime int64) (*schema.Job, error) {
	qb := sq.Select(schema.JobColumns...).From("job").
		Where("job.job_id = ?", jobId).
		Where("job.cluster = ?", cluster).
		Where("job.start_time = ?", startTime)

	sqlQuery, args, err := qb.ToSql()
	if err != nil {
		return nil, err
	}

	job, err := schema.ScanJob(r.DB.QueryRowx(sqlQuery, args...))

	// Reset error if no job is found as this is indicated by nil job ptr
	if err == sql.ErrNoRows {
		err = nil
	}
	return job, err
}

// FindById executes a SQL query to find a specific batch job.
// The job is queried using the database id.
// It returns a pointer to a schema.Job data structure and an error variable.
// If the job was not found nil is returned for the job pointer.
func (r *JobRepository) FindById(
	jobId int64) (*schema.Job, error) {
	sqlQuery, args, err := sq.Select(schema.JobColumns...).
		From("job").Where("job.id = ?", jobId).ToSql()
	if err != nil {
		return nil, err
	}

	job, err := schema.ScanJob(r.DB.QueryRowx(sqlQuery, args...))

	// Reset error if no job is found as this is indicated by nil job ptr
	if err == sql.ErrNoRows {
		err = nil
	}
	return job, err
}

func (r *JobRepository) Start(job schema.JobMeta) (res sql.Result, err error) {
	res, err = r.DB.NamedExec(`INSERT INTO job (
		job_id, user, project, cluster, `+"`partition`"+`, array_job_id, num_nodes, num_hwthreads, num_acc,
		exclusive, monitoring_status, smt, job_state, start_time, duration, resources, meta_data
	) VALUES (
		:job_id, :user, :project, :cluster, :partition, :array_job_id, :num_nodes, :num_hwthreads, :num_acc,
		:exclusive, :monitoring_status, :smt, :job_state, :start_time, :duration, :resources, :meta_data
	);`, job)
	return
}

func (r *JobRepository) Stop(
	jobId int64,
	duration int32,
	state schema.JobState,
	metricStats map[string]schema.JobStatistics) {

	stmt := sq.Update("job").
		Set("job_state", state).
		Set("duration", duration).
		Where("job.id = ?", jobId)

	for metric, stats := range metricStats {
		switch metric {
		case "flops_any":
			stmt = stmt.Set("flops_any_avg", stats.Avg)
		case "mem_used":
			stmt = stmt.Set("mem_used_max", stats.Max)
		case "mem_bw":
			stmt = stmt.Set("mem_bw_avg", stats.Avg)
		case "load":
			stmt = stmt.Set("load_avg", stats.Avg)
		case "net_bw":
			stmt = stmt.Set("net_bw_avg", stats.Avg)
		case "file_bw":
			stmt = stmt.Set("file_bw_avg", stats.Avg)
		}
	}

	sql, args, err := stmt.ToSql()

	if err != nil {
		log.Errorf("archiving job (dbid: %d) failed: %s", jobId, err.Error())
	}

	if _, err := r.DB.Exec(sql, args...); err != nil {
		log.Errorf("archiving job (dbid: %d) failed: %s", jobId, err.Error())
	}
}

func (r *JobRepository) AddTag(jobId int64, tagId int64) error {
	_, err := r.DB.Exec(`INSERT INTO jobtag (job_id, tag_id) VALUES (?, ?)`, jobId, tagId)
	return err
}

func (r *JobRepository) TagExists(tagType string, tagName string) (exists bool, tagId int64) {
	exists = true
	if err := sq.Select("id").From("tag").
		Where("tag.tag_type = ?", tagType).Where("tag.tag_name = ?", tagName).
		RunWith(r.DB).QueryRow().Scan(&tagId); err != nil {
		exists = false
		return exists, tagId
	} else {
		return exists, tagId
	}
}