import hljs from 'highlight.js/lib/core'
// Configs
import gradle from 'highlight.js/lib/languages/gradle'
// Coding
import groovy from 'highlight.js/lib/languages/groovy'
import ini from 'highlight.js/lib/languages/ini'
import java from 'highlight.js/lib/languages/java'
// Scripting
import javascript from 'highlight.js/lib/languages/javascript'
import json from 'highlight.js/lib/languages/json'
import kotlin from 'highlight.js/lib/languages/kotlin'
import lua from 'highlight.js/lib/languages/lua'
import properties from 'highlight.js/lib/languages/properties'
import python from 'highlight.js/lib/languages/python'
import scala from 'highlight.js/lib/languages/scala'
import xml from 'highlight.js/lib/languages/xml'
import yaml from 'highlight.js/lib/languages/yaml'
import mcfunction from 'highlightjs-mcfunction'

import type { ComponentRenderFn } from '@comark/html/render'
import type { ElementNode } from 'comark'

import { createModrinthHtmlRenderer, getFenceCodeText, getFenceLanguage } from '../markdown/parse'
import skript from './skript'

/* REGISTRATION */
// Scripting
hljs.registerLanguage('javascript', javascript)
hljs.registerLanguage('python', python)
hljs.registerLanguage('lua', lua)
hljs.registerLanguage('skript', skript)
hljs.registerLanguage('mcfunction', mcfunction)
// Coding
hljs.registerLanguage('java', java)
hljs.registerLanguage('kotlin', kotlin)
hljs.registerLanguage('scala', scala)
hljs.registerLanguage('groovy', groovy)
// Configs
hljs.registerLanguage('gradle', gradle)
hljs.registerLanguage('json', json)
hljs.registerLanguage('ini', ini)
hljs.registerLanguage('yaml', yaml)
hljs.registerLanguage('xml', xml)
hljs.registerLanguage('properties', properties)

/* ALIASES */
// Scripting
hljs.registerAliases(['js'], { languageName: 'javascript' })
hljs.registerAliases(['py'], { languageName: 'python' })
hljs.registerAliases(['sk'], { languageName: 'skript' })
hljs.registerAliases(['command'], { languageName: 'mcfunction' })
hljs.registerAliases(['kubejs'], { languageName: 'javascript' })
// Coding
hljs.registerAliases(['kt'], { languageName: 'kotlin' })
// Configs
hljs.registerAliases(['json5'], { languageName: 'json' })
hljs.registerAliases(['toml'], { languageName: 'ini' })
hljs.registerAliases(['yml'], { languageName: 'yaml' })
hljs.registerAliases(['html', 'htm', 'xhtml', 'mcui', 'fxml'], { languageName: 'xml' })

export { hljs }

function escapeHtml(value: string): string {
	return value.replace(/[&<>"']/g, (char) => {
		switch (char) {
			case '&':
				return '&amp;'
			case '<':
				return '&lt;'
			case '>':
				return '&gt;'
			case '"':
				return '&quot;'
			default:
				return '&#39;'
		}
	})
}

const highlightedPreComponent: ComponentRenderFn = (node) => {
	const preNode = node as ElementNode
	const codeText = getFenceCodeText(preNode)
	const language = getFenceLanguage(preNode)

	let inner: string
	let className: string | undefined

	if (language && hljs.getLanguage(language)) {
		try {
			inner = hljs.highlight(codeText, { language }).value
			className = `hljs language-${language}`
		} catch {
			inner = escapeHtml(codeText)
			className = `language-${language}`
		}
	} else {
		inner = escapeHtml(codeText)
		className = language ? `language-${language}` : undefined
	}

	return `<pre><code${className ? ` class="${className}"` : ''}>${inner}</code></pre>`
}

export const renderHighlightedString = createModrinthHtmlRenderer({ pre: highlightedPreComponent })

export const highlightCodeLines = (code: string, language: string): string[] => {
	if (!code) return []

	if (!hljs.getLanguage(language)) {
		return code.split('\n')
	}

	try {
		const highlighted = hljs.highlight(code, { language }).value
		const openTags: string[] = []

		const processedHtml = highlighted.replace(/(<span [^>]+>)|(<\/span>)|(\n)/g, (match) => {
			if (match === '\n') {
				return '</span>'.repeat(openTags.length) + '\n' + openTags.join('')
			}

			if (match === '</span>') {
				openTags.pop()
			} else {
				openTags.push(match)
			}

			return match
		})

		return processedHtml.split('\n')
	} catch {
		return code.split('\n')
	}
}