package repository

import (
	"database/sql"
	"pc-monitor-server/model"
	"time"
)

type AlertRepository struct {
	db *sql.DB
}

func NewAlertRepository(db *sql.DB) *AlertRepository {
	return &AlertRepository{db: db}
}

func (r *AlertRepository) CreateRule(rule *model.AlertRule) error {
	_, err := r.db.Exec(
		`INSERT INTO alert_rules (id, device_id, metric, operator, threshold, duration, created_at)
		 VALUES (?, ?, ?, ?, ?, ?, ?)`,
		rule.ID, rule.DeviceID, rule.Metric, rule.Operator, rule.Threshold, rule.Duration, rule.CreatedAt,
	)
	return err
}

func (r *AlertRepository) GetRulesByDevice(deviceID string) ([]model.AlertRule, error) {
	rows, err := r.db.Query(
		`SELECT id, device_id, metric, operator, threshold, duration, created_at
		 FROM alert_rules WHERE device_id=?`, deviceID)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var rules []model.AlertRule
	for rows.Next() {
		var rule model.AlertRule
		if err := rows.Scan(&rule.ID, &rule.DeviceID, &rule.Metric, &rule.Operator,
			&rule.Threshold, &rule.Duration, &rule.CreatedAt); err != nil {
			return nil, err
		}
		rules = append(rules, rule)
	}
	return rules, nil
}

func (r *AlertRepository) DeleteRule(id string) error {
	_, err := r.db.Exec("DELETE FROM alert_rules WHERE id=?", id)
	return err
}

func (r *AlertRepository) CreateAlert(alert *model.Alert) error {
	_, err := r.db.Exec(
		`INSERT INTO alerts (id, device_id, rule_id, metric, value, message, status, created_at)
		 VALUES (?, ?, ?, ?, ?, ?, ?, ?)`,
		alert.ID, alert.DeviceID, alert.RuleID, alert.Metric,
		alert.Value, alert.Message, alert.Status, alert.CreatedAt,
	)
	return err
}

func (r *AlertRepository) GetActiveAlerts() ([]model.Alert, error) {
	rows, err := r.db.Query(
		`SELECT id, device_id, rule_id, metric, value, message, status, created_at, resolved_at
		 FROM alerts WHERE status='active' ORDER BY created_at DESC`)
	if err != nil {
		return nil, err
	}
	defer rows.Close()

	var alerts []model.Alert
	for rows.Next() {
		var a model.Alert
		if err := rows.Scan(&a.ID, &a.DeviceID, &a.RuleID, &a.Metric,
			&a.Value, &a.Message, &a.Status, &a.CreatedAt, &a.ResolvedAt); err != nil {
			return nil, err
		}
		alerts = append(alerts, a)
	}
	return alerts, nil
}

func (r *AlertRepository) ResolveAlert(id string) error {
	now := time.Now()
	_, err := r.db.Exec(
		`UPDATE alerts SET status='resolved', resolved_at=? WHERE id=?`, now, id)
	return err
}