package db

import "strings"

// FailureAtlasPattern is one conditioned failure bucket in SQLite.
type FailureAtlasPattern struct {
	FingerprintBucket string
	Condition         string
	Tier              string
	FailCount         int
}

func (d *Database) UpsertFailureAtlasPattern(fingerprintBucket, condition, tier string) error {
	if d == nil {
		return nil
	}
	_, err := d.Exec(`
		INSERT INTO failure_atlas (fingerprint_bucket, condition, tier, fail_count, updated_at)
		VALUES (?, ?, ?, 1, CURRENT_TIMESTAMP)
		ON CONFLICT(fingerprint_bucket, condition, tier) DO UPDATE SET
		  fail_count = fail_count + 1,
		  updated_at = CURRENT_TIMESTAMP`,
		fingerprintBucket, condition, tier,
	)
	return err
}

func (d *Database) ListFailureAtlasPatterns(fingerprintBucket, goos string) ([]FailureAtlasPattern, error) {
	if d == nil {
		return nil, nil
	}
	out, err := d.queryFailureAtlasPatterns(`fingerprint_bucket = ?`, fingerprintBucket)
	if err != nil {
		return nil, err
	}
	if len(out) > 0 {
		return out, nil
	}
	if strings.TrimSpace(goos) == "" {
		return nil, nil
	}
	return d.queryFailureAtlasPatterns(`fingerprint_bucket LIKE ?`, strings.ToLower(goos)+"|%")
}

func (d *Database) queryFailureAtlasPatterns(whereClause string, arg interface{}) ([]FailureAtlasPattern, error) {
	query := `
		SELECT fingerprint_bucket, condition, tier, fail_count
		FROM failure_atlas
		WHERE ` + whereClause + `
		ORDER BY fail_count DESC, tier ASC`
	rows, err := d.Query(query, arg)
	if err != nil {
		return nil, err
	}
	defer rows.Close()
	var out []FailureAtlasPattern
	for rows.Next() {
		var p FailureAtlasPattern
		if err := rows.Scan(&p.FingerprintBucket, &p.Condition, &p.Tier, &p.FailCount); err != nil {
			return nil, err
		}
		out = append(out, p)
	}
	return out, rows.Err()
}