package page_test

import (
	"context"
	"errors"
	"fmt"

	"github.com/stephenafamo/bob"
	"github.com/stephenafamo/bob/dialect/sqlite"
	sd "github.com/stephenafamo/bob/dialect/sqlite/dialect"
	"github.com/stephenafamo/bob/dialect/sqlite/sm"
	"github.com/stephenafamo/bob/expr"
	"github.com/stephenafamo/scan"
	"go.auvem.com/corestack/page"
)

func Example() {
	ctx := context.Background()
	db, err := bob.Open("sqlite3", ":memory:")
	if err != nil {
		panic(err)
	}
	defer db.Close()
	db.SetMaxOpenConns(1)
	if _, err := db.ExecContext(ctx, "CREATE TABLE orders (id BIGINT PRIMARY KEY, priority BIGINT NOT NULL, tenant BIGINT NOT NULL)"); err != nil {
		panic(err)
	}
	if _, err := db.ExecContext(ctx, "INSERT INTO orders VALUES (1,10,7),(2,10,7),(3,5,7),(4,20,8)"); err != nil {
		panic(err)
	}
	type Order struct {
		ID       int64
		Priority int64
	}
	sort := page.Sort{ID: "orders/priority/v1", Columns: []page.Column{
		{Expression: expr.Quote("priority"), Direction: page.Desc},
		{Expression: expr.Quote("id"), Direction: page.Asc, Unique: true},
	}}
	// With Bob-generated models, use their column references for these expressions.
	// The key must independently match their order and actual stored value types.
	key := func(o Order) []any { return []any{o.Priority, o.ID} }
	p, err := page.Prepare(sort, key, page.Request{Size: 2}, page.Limits{Default: 2, Maximum: 100})
	if err != nil {
		panic(err)
	}
	q := sqlite.Select(sm.Columns("id", "priority"), sm.From("orders"), page.Mod[*sd.SelectQuery](p))
	q.Apply(sm.Where(sqlite.Quote("tenant").EQ(sqlite.Arg(int64(7)))))
	rows, err := bob.All(ctx, db, q, scan.StructMapper[Order]())
	if err != nil {
		panic(err)
	}
	result, err := p.Page(rows)
	if err != nil {
		panic(err)
	}
	fmt.Println(result.Items, result.HasNext, result.HasPrevious)
	// Continue with Forward + result.EndCursor, or Backward + result.StartCursor.
	// A mismatched key returns no partial Page, including for an overflow row.
	bad, err := page.Prepare(sort, func(o Order) []any { return []any{o.ID} }, page.Request{}, page.Limits{Default: 2, Maximum: 100})
	if err != nil {
		panic(err)
	}
	_, err = bad.Page(rows)
	var keyError *page.KeyError
	fmt.Println(errors.As(err, &keyError), keyError.Expected, keyError.Actual)
	// Output:
	// [{1 10} {2 10}] true false
	// true 2 1
}