/**
 * try to parse a GCode config string into a number
 * @param str the string to try parsing
 * @returns a number if parsing happened correctly or undefined
 */
function parseNumber(str: string): number | undefined {
	if (!/^(\d|\.)+$/g.test(str)) {
		return undefined
	}
	const float = parseFloat(str)
	const int = parseInt(str, 10)
	if (isNaN(int)) {
		return undefined
	}
	if (int !== float) {
		return float
	}
	return int
}

/**
 * decode a print time to a number of seconds
 * @param text the text to decode
 * @returns the number of seconds in the text
 */
function decodeTime(text: string): number {
	let timeInSec = 0
	for (const it of text.split(' ')) {
		const lastChar = it.charAt(it.length - 1)
		const time = parseInt(it.slice(0, it.length - 1), 10)
		switch (lastChar) {
			case 'm':
				timeInSec += time * 60
				break;
			case 's':
				timeInSec += time
				break;
			case 'h':
				timeInSec += time * 60 * 60
				break;
			case 'd':
				timeInSec += time * 60 * 60 * 24
				break;
			default:
				throw new Error(`error parsing time ${it} (${time})`)
		}
	}
	return timeInSec
}

export function getParams(data: string) {
	// get the configuration lines
	const lines = data.split('\n').filter((it) => it.startsWith(';') && it.includes('='))
	// create the config object
	const obj: Record<string, string | number> = {}
	// loop through eacj config
	for (const line of lines) {
		// get its key and value
		const [key, value] = line.split('=', 2).map((it) => it.slice(1).trim())
		// sip if it has no key or value
		if (!key || !value) {
			continue
		}
		// process the key
		let realKey = key
			// replace spaces by _
			.replace(/ /g, '_')
			// remove unparseable characters
			.replace(/\[|\]|\(|\)/g, '')
		// process the value
		const realValue = parseNumber(value) ?? value
		// add an offset if the key is already cited
		let offset = 0
		while (obj[`${realKey}${offset > 0 ? `_${offset}` : ''}`] && obj[`${realKey}${offset > 0 ? `_${offset}` : ''}`] !== realValue) {
			offset++
		}
		// chnge the key to add the offset
		if (offset > 0) {
			realKey = `${realKey}_${offset}`
		}
		// detect key collisions
		if (obj[realKey] && obj[realKey] !== realValue) {
			throw new Error(`Key collision ${key}=${realValue} ${realKey}=${obj[realKey]}`)
		}
		// set the value to the key
		obj[realKey] = realValue
		// transform the time to a number of seconds
		if (realKey === 'estimated_printing_time_normal_mode') {
			obj['estimated_printing_time_seconds'] = decodeTime(value)
		}
	}
	return obj
}