package app

import (
	"context"
	"log"
	"time"
)

// The address table holds a stranger's door number and phone. Keeping that
// after the job is over buys nothing and costs a lot if the database ever
// leaks, so a finished task schedules its address for erasure and this worker
// carries it out. The city and street stay: they are what the history reads
// from, and they were public on the listing anyway.

func (a *App) scheduleAddressPurge(ctx context.Context) int64 {
	days := a.configInt(ctx, "pet.address_purge_days", 7)
	if days < 1 {
		days = 7
	}
	// 只给"没有任何进行中任务"的地址排期；主人常用的地址不会因为一次任务结束就被清空。
	result, err := a.db.ExecContext(ctx, `UPDATE pet_addresses addr
		JOIN (SELECT address_id,MAX(updated_at) AS finished FROM pet_feed_tasks
			WHERE status IN ('SETTLED','REFUNDED','CANCELLED','ARBITRATED') GROUP BY address_id) ended
		ON ended.address_id=addr.id
		SET addr.purge_at=DATE_ADD(ended.finished,INTERVAL ? DAY)
		WHERE addr.purge_at IS NULL
		AND NOT EXISTS (SELECT 1 FROM pet_feed_tasks live WHERE live.address_id=addr.id
			AND live.status IN ('CREATED','ESCROWED','ASSIGNED','SERVING','COMPLETED','DISPUTED'))`, days)
	if err != nil {
		log.Printf("pet address purge scheduling failed: %v", err)
		return 0
	}
	affected, _ := result.RowsAffected()
	return affected
}

func (a *App) purgeDueAddresses(ctx context.Context) int64 {
	// 一个地址重新被用于新任务时会清掉 purge_at；这里再确认一次没有活任务，
	// 免得排期和复用之间抢到一起。
	result, err := a.db.ExecContext(ctx, `UPDATE pet_addresses addr
		SET addr.detail_cipher='',addr.contact_cipher='',addr.emergency_cipher=NULL,addr.vet_hospital='',
			addr.latitude=NULL,addr.longitude=NULL,addr.purge_at=NULL
		WHERE addr.purge_at IS NOT NULL AND addr.purge_at<=NOW(3)
		AND NOT EXISTS (SELECT 1 FROM pet_feed_tasks live WHERE live.address_id=addr.id
			AND live.status IN ('CREATED','ESCROWED','ASSIGNED','SERVING','COMPLETED','DISPUTED'))`)
	if err != nil {
		log.Printf("pet address purge failed: %v", err)
		return 0
	}
	affected, _ := result.RowsAffected()
	if affected > 0 {
		log.Printf("pet address purge: cleared plaintext for %d addresses", affected)
	}
	return affected
}

func (a *App) startAddressPurgeWorker(ctx context.Context) {
	go func() {
		ticker := time.NewTicker(time.Hour)
		defer ticker.Stop()
		for {
			select {
			case <-ctx.Done():
				return
			case <-ticker.C:
				a.scheduleAddressPurge(ctx)
				a.purgeDueAddresses(ctx)
			}
		}
	}()
}