package main

import (
	"context"
	"encoding/json"
	"flag"
	"fmt"
	"log"
	"os"
	"strings"

	"git.amiirkhl.ir/starcoach-hackathon/zarinpal-analytics-backend/internal/config"
	"git.amiirkhl.ir/starcoach-hackathon/zarinpal-analytics-backend/internal/database"
	"github.com/jackc/pgx/v5"
)

type rowCount struct {
	Before int64 `json:"before"`
	After  int64 `json:"after"`
}

func main() {
	apply := flag.Bool("apply", false, "commit the reset; without this flag the transaction is rolled back")
	keysFlag := flag.String("terminals", "T83,T88", "comma-separated exact terminal source keys")
	flag.Parse()
	keys := splitKeys(*keysFlag)
	if len(keys) != 2 || keys[0] != "T83" || keys[1] != "T88" {
		log.Fatal("this operation is deliberately scoped to exactly T83,T88")
	}
	cfg, err := config.Load()
	if err != nil {
		log.Fatal(err)
	}
	ctx := context.Background()
	pool, err := database.Open(ctx, cfg.DatabaseURL)
	if err != nil {
		log.Fatal(err)
	}
	defer pool.Close()
	tx, err := pool.BeginTx(ctx, pgx.TxOptions{IsoLevel: pgx.Serializable})
	if err != nil {
		log.Fatal(err)
	}
	defer func() { _ = tx.Rollback(ctx) }()
	if _, err := tx.Exec(ctx, `CREATE TEMP TABLE reset_targets(terminal_id bigint PRIMARY KEY,merchant_id bigint NOT NULL,source_key text NOT NULL UNIQUE) ON COMMIT DROP`); err != nil {
		log.Fatal(err)
	}
	for _, key := range keys {
		var count int
		if err := tx.QueryRow(ctx, `SELECT count(*) FROM terminals WHERE source_key=$1`, key).Scan(&count); err != nil {
			log.Fatal(err)
		}
		if count != 1 {
			log.Fatalf("terminal %s resolved to %d records; refusing reset", key, count)
		}
		if _, err := tx.Exec(ctx, `INSERT INTO reset_targets SELECT id,merchant_id,source_key FROM terminals WHERE source_key=$1`, key); err != nil {
			log.Fatal(err)
		}
	}
	if _, err := tx.Exec(ctx, `CREATE TEMP TABLE reset_entity_ids(entity_id text PRIMARY KEY) ON COMMIT DROP`); err != nil {
		log.Fatal(err)
	}
	if _, err := tx.Exec(ctx, `INSERT INTO reset_entity_ids
		SELECT id FROM growth_coach_profiles WHERE terminal_id IN(SELECT terminal_id FROM reset_targets)
		UNION SELECT id FROM growth_coach_plans WHERE terminal_id IN(SELECT terminal_id FROM reset_targets)
		UNION SELECT id FROM growth_coach_recommendations WHERE terminal_id IN(SELECT terminal_id FROM reset_targets)
		UNION SELECT id FROM golden_steps WHERE terminal_id IN(SELECT terminal_id FROM reset_targets)
		UNION SELECT id FROM monthly_goals WHERE terminal_id IN(SELECT terminal_id FROM reset_targets)
		UNION SELECT s.id FROM goal_subtasks s JOIN monthly_goals g ON g.id=s.goal_id WHERE g.terminal_id IN(SELECT terminal_id FROM reset_targets)
		UNION SELECT p.id FROM goal_deadline_proposals p JOIN monthly_goals g ON g.id=p.goal_id WHERE g.terminal_id IN(SELECT terminal_id FROM reset_targets)
		UNION SELECT id FROM growth_coach_jobs WHERE terminal_id IN(SELECT terminal_id FROM reset_targets)
		UNION SELECT id FROM growth_coach_difficulty_proposals WHERE terminal_id IN(SELECT terminal_id FROM reset_targets)`); err != nil {
		log.Fatal(err)
	}
	counts := map[string]rowCount{}
	for table, predicate := range resetScopes() {
		before, err := countRows(ctx, tx, table, predicate)
		if err != nil {
			log.Fatal(err)
		}
		counts[table] = rowCount{Before: before}
	}
	statements := []string{
		`INSERT INTO ai_generation_holds(terminal_id,merchant_id,reason) SELECT terminal_id,merchant_id,'ONBOARDING_REQUIRED' FROM reset_targets ON CONFLICT(terminal_id) DO UPDATE SET reason='ONBOARDING_REQUIRED',created_at=now()`,
		`DELETE FROM growth_report_idempotency i USING growth_reports r,reset_targets t WHERE i.report_id=r.id AND r.terminal_id=t.terminal_id`,
		`DELETE FROM growth_reports r USING reset_targets t WHERE r.terminal_id=t.terminal_id`,
		`DELETE FROM ai_insight_refresh_attempts a USING reset_targets t WHERE a.merchant_id=t.merchant_id AND a.terminal_source_key=t.source_key`,
		`DELETE FROM ai_insight_snapshots s USING reset_targets t WHERE s.terminal_id=t.terminal_id`,
		`DELETE FROM goal_deadline_proposals p USING monthly_goals g,reset_targets t WHERE p.goal_id=g.id AND g.terminal_id=t.terminal_id`,
		`DELETE FROM goal_subtasks s USING monthly_goals g,reset_targets t WHERE s.goal_id=g.id AND g.terminal_id=t.terminal_id`,
		`DELETE FROM monthly_goals g USING reset_targets t WHERE g.terminal_id=t.terminal_id`,
		`DELETE FROM growth_coach_progress_snapshots p USING golden_steps s,reset_targets t WHERE p.action_id=s.id AND s.terminal_id=t.terminal_id`,
		`DELETE FROM golden_steps s USING reset_targets t WHERE s.terminal_id=t.terminal_id`,
		`DELETE FROM growth_coach_outcome_reviews o USING growth_coach_plans p,reset_targets t WHERE o.plan_id=p.id AND p.terminal_id=t.terminal_id`,
		`DELETE FROM growth_coach_recommendations r USING reset_targets t WHERE r.terminal_id=t.terminal_id`,
		`DELETE FROM growth_coach_events e USING reset_targets t WHERE e.terminal_id=t.terminal_id`,
		`DELETE FROM growth_coach_difficulty_proposals p USING reset_targets t WHERE p.terminal_id=t.terminal_id`,
		`DELETE FROM growth_coach_jobs j USING reset_targets t WHERE j.terminal_id=t.terminal_id`,
		`DELETE FROM growth_coach_plans p USING reset_targets t WHERE p.terminal_id=t.terminal_id`,
		`DELETE FROM growth_coach_idempotency i USING reset_targets t WHERE i.merchant_id=t.merchant_id AND (i.response::text LIKE '%"terminalId":"'||t.source_key||'"%' OR EXISTS(SELECT 1 FROM reset_entity_ids e WHERE i.response::text LIKE '%'||e.entity_id||'%'))`,
		`DELETE FROM growth_coach_profiles p USING reset_targets t WHERE p.terminal_id=t.terminal_id`,
	}
	for _, statement := range statements {
		if _, err := tx.Exec(ctx, statement); err != nil {
			log.Fatal(err)
		}
	}
	for table, predicate := range resetScopes() {
		after, err := countRows(ctx, tx, table, predicate)
		if err != nil {
			log.Fatal(err)
		}
		value := counts[table]
		value.After = after
		counts[table] = value
	}
	var holds int64
	if err := tx.QueryRow(ctx, `SELECT count(*) FROM ai_generation_holds h JOIN reset_targets t ON t.terminal_id=h.terminal_id WHERE h.reason='ONBOARDING_REQUIRED'`).Scan(&holds); err != nil {
		log.Fatal(err)
	}
	result := map[string]any{"mode": "dry-run", "terminals": keys, "rows": counts, "paymentsDeleted": 0, "generationHolds": holds}
	if *apply {
		if err := tx.Commit(ctx); err != nil {
			log.Fatal(err)
		}
		result["mode"] = "applied"
	} else if err := tx.Rollback(ctx); err != nil {
		log.Fatal(err)
	}
	encoded, _ := json.MarshalIndent(result, "", "  ")
	_, _ = os.Stdout.Write(append(encoded, '\n'))
}

func splitKeys(value string) []string {
	parts := strings.Split(value, ",")
	result := make([]string, 0, len(parts))
	for _, part := range parts {
		if item := strings.TrimSpace(part); item != "" {
			result = append(result, item)
		}
	}
	return result
}

func resetScopes() map[string]string {
	return map[string]string{
		"growth_reports":                    `terminal_id IN(SELECT terminal_id FROM reset_targets)`,
		"growth_report_idempotency":         `report_id IN(SELECT id FROM growth_reports WHERE terminal_id IN(SELECT terminal_id FROM reset_targets))`,
		"ai_insight_snapshots":              `terminal_id IN(SELECT terminal_id FROM reset_targets)`,
		"ai_insight_jobs":                   `snapshot_id IN(SELECT id FROM ai_insight_snapshots WHERE terminal_id IN(SELECT terminal_id FROM reset_targets))`,
		"ai_insight_events":                 `job_id IN(SELECT id FROM ai_insight_jobs WHERE snapshot_id IN(SELECT id FROM ai_insight_snapshots WHERE terminal_id IN(SELECT terminal_id FROM reset_targets)))`,
		"ai_insight_refresh_attempts":       `(merchant_id,terminal_source_key) IN(SELECT merchant_id,source_key FROM reset_targets)`,
		"growth_coach_profiles":             `terminal_id IN(SELECT terminal_id FROM reset_targets)`,
		"growth_coach_plans":                `terminal_id IN(SELECT terminal_id FROM reset_targets)`,
		"growth_coach_recommendations":      `terminal_id IN(SELECT terminal_id FROM reset_targets)`,
		"golden_steps":                      `terminal_id IN(SELECT terminal_id FROM reset_targets)`,
		"monthly_goals":                     `terminal_id IN(SELECT terminal_id FROM reset_targets)`,
		"goal_subtasks":                     `goal_id IN(SELECT id FROM monthly_goals WHERE terminal_id IN(SELECT terminal_id FROM reset_targets))`,
		"goal_deadline_proposals":           `goal_id IN(SELECT id FROM monthly_goals WHERE terminal_id IN(SELECT terminal_id FROM reset_targets))`,
		"growth_coach_progress_snapshots":   `action_id IN(SELECT id FROM golden_steps WHERE terminal_id IN(SELECT terminal_id FROM reset_targets))`,
		"growth_coach_jobs":                 `terminal_id IN(SELECT terminal_id FROM reset_targets)`,
		"growth_coach_events":               `terminal_id IN(SELECT terminal_id FROM reset_targets)`,
		"growth_coach_difficulty_proposals": `terminal_id IN(SELECT terminal_id FROM reset_targets)`,
		"growth_coach_outcome_reviews":      `plan_id IN(SELECT id FROM growth_coach_plans WHERE terminal_id IN(SELECT terminal_id FROM reset_targets))`,
		"growth_coach_idempotency":          `EXISTS(SELECT 1 FROM reset_targets t WHERE growth_coach_idempotency.merchant_id=t.merchant_id AND (growth_coach_idempotency.response::text LIKE '%"terminalId":"'||t.source_key||'"%' OR EXISTS(SELECT 1 FROM reset_entity_ids e WHERE growth_coach_idempotency.response::text LIKE '%'||e.entity_id||'%')))`,
	}
}

func countRows(ctx context.Context, tx pgx.Tx, table, predicate string) (int64, error) {
	var count int64
	err := tx.QueryRow(ctx, fmt.Sprintf("SELECT count(*) FROM %s WHERE %s", table, predicate)).Scan(&count)
	return count, err
}