import { readFileSync, readdirSync, statSync } from 'node:fs'
import { join } from 'node:path'
import { describe, expect, it } from 'vitest'

const root = process.cwd()

function walk(dir: string, found: string[] = []): string[] {
	for (const name of readdirSync(dir)) {
		const path = join(dir, name)

		if (statSync(path).isDirectory()) {
			walk(path, found)
			continue
		}

		if (name.endsWith('.tsx') || name.endsWith('.ts')) {
			found.push(path)
		}
	}

	return found
}

const sources = walk(join(root, 'src'))

function read(path: string): string {
	return readFileSync(path, 'utf8')
}

function offenders(test: (text: string, path: string) => boolean): string[] {
	return sources.filter(path => test(read(path), path)).map(path => path.replace(`${root}/`, ''))
}

const css = read(join(root, 'src/app/globals.css'))

describe('Farbmodus', () => {
	it('setzt data-theme nicht fest ins Server-HTML, sonst überschreibt React die gespeicherte Wahl', () => {
		expect(offenders(text => /<html[^>]*\sdata-theme=/u.test(text))).toEqual([])
	})

	it('definiert jede Farbe für beide Modi', () => {
		const block = (start: string): string => {
			const from = css.indexOf(start)

			return from === -1 ? '' : css.slice(from, css.indexOf('\n}', from))
		}

		const names = (text: string): string[] =>
			[...text.matchAll(/--color-([a-z0-9-]+):/gu)]
				.map(match => match[1])
				.filter((name): name is string => name !== undefined)

		const light = names(block('@theme {'))
		const dark = new Set(names(block(':root[data-theme="dark"] {')))
		const missing = light.filter(name => !dark.has(name) && !name.startsWith('shot'))

		expect(missing).toEqual([])
	})

	it('mischt Schatten nicht aus der Tintenfarbe, weil die im Dunkeln hell ist', () => {
		expect(offenders(text => /shadow-ink|shadow-\[.*var\(--color-ink/u.test(text))).toEqual([])
	})

	it('führt Schatten über ein Token, das den Modus kennt', () => {
		expect(css).toContain('--shadow-lift')
		expect(css.match(/--shadow-lift/gu)?.length ?? 0).toBeGreaterThanOrEqual(2)
	})
})

describe('Aufbau', () => {
	it('hält den Fuß unten, auch wenn die Seite kurz ist', () => {
		expect(read(join(root, 'src/components/layout/SiteFooter.tsx'))).toContain('mt-auto')
		expect(read(join(root, 'src/components/layout/AppShell.tsx'))).toContain('min-h-full')
	})

	it('benutzt für alle Bereiche dieselbe Hülle', () => {
		const site = read(join(root, 'src/app/(site)/layout.tsx'))
		const admin = read(join(root, 'src/app/admin/layout.tsx'))

		expect(site).toContain('AppShell')
		expect(admin).toContain('AppShell')
	})

	it('kennt genau zwei Breiten und keine erfundenen', () => {
		expect(css).toContain('--container-page')
		expect(css).toContain('--container-read')
		expect(offenders(text => /max-w-\[\d/u.test(text))).toEqual([])
	})
})

describe('Schreibweisen', () => {
	it('benutzt keine Pixelangaben in Klassen', () => {
		expect(offenders(text => /(?:w|h|p|m|gap|text|top|left|right|bottom)-\[\d+px\]/u.test(text))).toEqual([])
	})

	it('lässt keine Kommentare im Quelltext', () => {
		expect(offenders((text, path) => !path.endsWith('.d.ts') && /^\s*\/\//mu.test(text))).toEqual([])
	})

	it('benutzt keine Gedankenstriche', () => {
		const files = [...sources, join(root, 'messages/de.json'), join(root, 'messages/en.json')]
		const hits = files.filter(path => /[–—]/u.test(read(path))).map(path => path.replace(`${root}/`, ''))

		expect(hits).toEqual([])
	})

	it('schreibt Umlaute aus', () => {
		const de = read(join(root, 'messages/de.json'))

		expect(de).not.toMatch(/\b(ueber|fuer|koennen|muessen|groesse|waehlen)\b/u)
	})

	it('benutzt keine Emojis', () => {
		const files = [...sources, join(root, 'messages/de.json'), join(root, 'messages/en.json')]
		const hits = files.filter(path => /\p{Extended_Pictographic}/u.test(read(path))).map(path => path.replace(`${root}/`, ''))

		expect(hits).toEqual([])
	})
})

describe('Bedienbarkeit', () => {
	it('führt jeden scrollbaren Bereich über den Scroller statt nativ', () => {
		expect(offenders(text => /overflow-(?:y|x)-(?:auto|scroll)/u.test(text))).toEqual([])
	})

	it('hält das globale Stylesheet klein', () => {
		expect(css.split('\n').length).toBeLessThanOrEqual(200)
	})

	it('macht den Tastaturfokus sichtbar', () => {
		expect(css).toMatch(/:focus-visible/u)
	})

	it('nimmt Rücksicht auf abgeschaltete Bewegung', () => {
		const moving = offenders(text => /animate-rise|transition-/u.test(text))
		const careless = moving.filter(path => !/motion-reduce/u.test(read(join(root, path))))

		expect(careless).toEqual([])
	})
})

describe('Sprache der Oberfläche', () => {
	it('hält beide Sprachdateien auf denselben Schlüsseln', () => {
		const keys = (value: unknown, prefix = ''): string[] => {
			if (typeof value !== 'object' || value === null) {
				return [prefix]
			}

			return Object.entries(value as Record<string, unknown>).flatMap(([key, inner]) =>
				keys(inner, prefix === '' ? key : `${prefix}.${key}`))
		}

		const de = keys(JSON.parse(read(join(root, 'messages/de.json')))).sort()
		const en = keys(JSON.parse(read(join(root, 'messages/en.json')))).sort()

		expect(de.filter(key => !en.includes(key))).toEqual([])
		expect(en.filter(key => !de.includes(key))).toEqual([])
	})
})