package config

import (
	"errors"
	"reflect"
	"time"
)

// JSCKServerTimeouts is the server timeouts section's configuration key.
const JSCKServerTimeouts string = "timeouts"

// JSCServerTimeouts configures the server's HTTP timeouts, as those of
// http.Server: ReadHeaderTimeout for reading a request's headers,
// ReadTimeout for the whole request, WriteTimeout for writing the response
// and IdleTimeout for waiting for the next request on a keep-alive
// connection. 0 or less means no limit, except that ReadHeaderTimeout must be
// greater than 0 (see validate). ShutdownTimeout is how long shutdown waits
// for clients to close; 0 or less means it waits until they have.
type JSCServerTimeouts struct {
	ReadHeaderTimeout time.Duration `cfg:"read_header" default:"5s"`
	ReadTimeout       time.Duration `cfg:"read"        default:"15s"`
	WriteTimeout      time.Duration `cfg:"write"       default:"30s"`
	IdleTimeout       time.Duration `cfg:"idle"        default:"2m"`
	ShutdownTimeout   time.Duration `cfg:"shutdown"    default:"15s"`
}

// ---------- Section methods (see Section) ----------

// Map implements Section.
func (c JSCServerTimeouts) Map() map[string]any { return mapOf(c) }

// Flatten implements Section.
func (c JSCServerTimeouts) Flatten() map[string]any {
	return flattenOf(JSCKServerTimeouts, c)
}

// TypeOf implements Section.
func (c JSCServerTimeouts) TypeOf(key string) (reflect.Kind, error) {
	return typeOf(c, key)
}

// ValueOf implements Section.
func (c JSCServerTimeouts) ValueOf(key string) (any, error) {
	return valueOf(c, key)
}

// SetValue implements Section.
func (c *JSCServerTimeouts) SetValue(key string, value any) error {
	return setValue(c, key, value)
}

// ---------- Section specific methods ----------

// validate checks values before they are stored (see validator).
// read_header must be greater than 0: without it a client could hold a
// connection open for ever by sending its headers slowly (slowloris).
func (c *JSCServerTimeouts) validate(key string, value any) error {
	if key == "read_header" && value.(time.Duration) <= 0 {
		return errors.New(
			"config: read_header must be greater than 0, as a client could otherwise hold a connection open for ever",
		)
	}
	return nil
}