package repository

import (
	"context"
	"encoding/json"
	"errors"
	"strings"

	"github.com/google/uuid"
	"github.com/jackc/pgx/v5"
	"github.com/jackc/pgx/v5/pgconn"
)

// FunnelDefinitionWriteInput is create/update payload.
type FunnelDefinitionWriteInput struct {
	Code   string
	Title  string
	Active bool
}

// CreateFunnelDefinitionWithAudit inserts and audits.
func (r *AdminRepo) CreateFunnelDefinitionWithAudit(
	ctx context.Context, adminID uuid.UUID, in FunnelDefinitionWriteInput, meta json.RawMessage,
) (*FunnelDefinitionRow, error) {
	tx, err := r.Pool.Begin(ctx)
	if err != nil {
		return nil, err
	}
	defer tx.Rollback(ctx)
	var row FunnelDefinitionRow
	err = tx.QueryRow(ctx, `
		INSERT INTO funnel_definitions(code, title, active, system)
		VALUES ($1,$2,$3,false)
		RETURNING id, code, title, active, system, updated_at`,
		in.Code, in.Title, in.Active,
	).Scan(&row.ID, &row.Code, &row.Title, &row.Active, &row.System, &row.UpdatedAt)
	if err != nil {
		return nil, mapFunnelDefinitionWriteErr(err)
	}
	if meta == nil {
		meta = json.RawMessage(`{}`)
	}
	if _, err := tx.Exec(ctx, `
		INSERT INTO admin_audit_logs(admin_id, action, target_type, target_id, meta)
		VALUES ($1,'growth.funnel_definition.create','funnel_definition',$2,$3)`,
		adminID, row.ID.String(), meta,
	); err != nil {
		return nil, err
	}
	if err := tx.Commit(ctx); err != nil {
		return nil, err
	}
	return &row, nil
}

// UpdateFunnelDefinitionWithAudit updates and audits.
func (r *AdminRepo) UpdateFunnelDefinitionWithAudit(
	ctx context.Context, adminID, id uuid.UUID, in FunnelDefinitionWriteInput, meta json.RawMessage,
) (*FunnelDefinitionRow, error) {
	tx, err := r.Pool.Begin(ctx)
	if err != nil {
		return nil, err
	}
	defer tx.Rollback(ctx)
	var system bool
	var oldCode string
	err = tx.QueryRow(ctx, `SELECT system, code FROM funnel_definitions WHERE id=$1`, id).Scan(&system, &oldCode)
	if errors.Is(err, pgx.ErrNoRows) {
		return nil, pgx.ErrNoRows
	}
	if err != nil {
		return nil, err
	}
	code := in.Code
	if system {
		code = oldCode
	}
	var row FunnelDefinitionRow
	err = tx.QueryRow(ctx, `
		UPDATE funnel_definitions
		SET code=$2, title=$3, active=$4, updated_at=now()
		WHERE id=$1
		RETURNING id, code, title, active, system, updated_at`,
		id, code, in.Title, in.Active,
	).Scan(&row.ID, &row.Code, &row.Title, &row.Active, &row.System, &row.UpdatedAt)
	if err != nil {
		return nil, mapFunnelDefinitionWriteErr(err)
	}
	if meta == nil {
		meta = json.RawMessage(`{}`)
	}
	if _, err := tx.Exec(ctx, `
		INSERT INTO admin_audit_logs(admin_id, action, target_type, target_id, meta)
		VALUES ($1,'growth.funnel_definition.update','funnel_definition',$2,$3)`,
		adminID, id.String(), meta,
	); err != nil {
		return nil, err
	}
	if err := tx.Commit(ctx); err != nil {
		return nil, err
	}
	return &row, nil
}

func mapFunnelDefinitionWriteErr(err error) error {
	var pgErr *pgconn.PgError
	if errors.As(err, &pgErr) && pgErr.Code == "23505" {
		return errString("funnel definition code conflict")
	}
	return err
}

// FunnelDefinitionCodeConflict reports unique violation.
func FunnelDefinitionCodeConflict(err error) bool {
	return err != nil && strings.Contains(err.Error(), "funnel definition code conflict")
}