import { createElement, Fragment } from 'react'
import type { Chapter } from '../../ui/types.ts'
import driver from '../onedim/driver.m?raw'
import script from './highorder.m?raw'
import text from './text.md?raw'
import { Convergence, WorkPrecision, fmtErr, type SweepOut } from '../onedim/panels.tsx'
import { KIND_CONTROL } from '../shared.ts'

const NS = [16, 64, 256, 1024, 4096, 16384]

export const ch03: Chapter = {
  id: 'higher-order',
  nav: 'Two more orders, almost free',
  part: 'One dimension',
  title: 'Two more orders, almost free',
  blurb: 'The compact fourth-order scheme, and how to read a work-precision diagram.',
  text,
  labs: [
    {
      id: 'orders',
      title: 'Second order against fourth',
      caption:
        'Both schemes solve the same tridiagonal system; only the right-hand side differs. The second figure is the one that decides anything.',
      driver,
      script,
      editorOpen: true,
      controls: [KIND_CONTROL],
      defaults: { kind: 'smooth', mode: 'sweep', ns: NS, nmaxs: [16384, 16384], timed: 1 },
      render: (d: SweepOut) =>
        createElement(
          Fragment,
          null,
          createElement(Convergence, {
            key: 'c',
            data: d,
            style: {
              slots: ['fd2', 'fd4'],
              refs: [
                { p: -2, label: 'slope −2' },
                { p: -4, label: 'slope −4' },
              ],
            },
          }),
          createElement(WorkPrecision, { key: 'w', data: d, style: { slots: ['fd2', 'fd4'] } }),
        ),
      summary: (d: SweepOut) => [
        { label: 'best 2nd order', value: fmtErr(Math.min(...(d.E[0].filter((v) => v != null) as number[]))) },
        { label: 'best 4th order', value: fmtErr(Math.min(...(d.E[1].filter((v) => v != null) as number[]))) },
      ],
    },
  ],
}