// deno-lint-ignore-file no-explicit-any
const name = Deno.mainModule.replace(/.*\/([^\\]+)\.ts$/, '$1')
try { Deno.statSync('./logs/') } catch { Deno.mkdirSync('./logs/') }
const file = Deno.createSync(`./logs/${name}-${new Date().toJSON().replaceAll(':', '_')}.log`)
const config = {
	dateFormat: 'y-m-d H:M:S.T',
	prefixEmptyLines: false,
	colors: {error: 'red', warn: 'yellow', log: 'lightgray', info: 'blue', debug: 'gray', timer: 'green'}
}
const fmtDate = (date: Date, fmt: string) => {
	const o = {
		'y': date.getFullYear(),
		'm': date.getMonth() + 1,
		'd': date.getDate(),
		'H': date.getHours(),
		'M': date.getMinutes(),
		'S': date.getSeconds(),
		'T': date.getMilliseconds()
	}
	return [...fmt].map(c => o[c as keyof typeof o]?.toString()?.padStart(c === 'T'? 3 : 2, '0') || c).join('')
}
const getPrefix = (type: string) => [`[${fmtDate(new Date, config.dateFormat)}]`, `[${type.padStart(5, ' ')}]`]
const formatParams = (data: any[]) => {
	const records = []
	for (let i = 0; i < data.length; ++i)
		records.push((typeof data[i] === 'string') ? data[i] : Deno.inspect(data[i]))
	return records.join(' ')
}
// count '%c' in a string but ignore '%%c'
const findColorSpecifiers = (s: string) => {
	const r = []
	for (let i = 0; i < s.length - 1; ++i) {
		if (s[i] === '%' && s[i + 1] === 'c' && (i === 0 || s[i - 1] !== '%'))
			r.push(i)
	}
	return r
}
const removeColorSpecifiers = (s: string, removeLimit: number) => {
	const cs = findColorSpecifiers(s).slice(0, removeLimit)
	let r = ''
	let p = 0
	for (const c of cs) {
		r += s.slice(p, c)
		p = c + 2
	}
	r += s.slice(p)
	return r
}

const rawConsole = {...globalThis.console}

const timestampedLeveledLog = (level: keyof typeof config.colors, data: any[]) => {
	const [dp, lp] = getPrefix(level)
	const emptyLineIntention = data.length === 0
	if (data.length === 0) data = ['']

	let fi = 1
	const outputInfo: {l: string, colors: string[]}[] = []
	if (typeof data[0] === 'string') {
		const lines = data[0].split('\n')
		for (const l of lines) {
			const c = findColorSpecifiers(l).length
			outputInfo.push({l, colors: data.slice(fi, fi + c)})
			fi += c
		}
	} else {
		outputInfo.push(...formatParams([data[0]]).split('\n').map(l => ({l, colors: []})))
	}

	if (fi < data.length) {
		const remainingLines = formatParams(data.slice(fi)).split('\n')
		outputInfo[outputInfo.length - 1].l += ' '+ remainingLines.shift()
		for (const l of remainingLines) {
			outputInfo.push({ l, colors: [] })
		}
	}

	const pf = `color:${config.colors[level]}`
	let currentUserColorFormat = pf
	for (let i = 0; i < outputInfo.length; ++i) {
		const c = outputInfo[i]
		const connector = outputInfo.length === 1 ? '─' : (i === 0 ? '┬' : i === outputInfo.length - 1 ? '└' : '├')
		if (config.prefixEmptyLines === false && emptyLineIntention) {
			// if there is only one line and it's empty, don't prefix it
		} else {
			c.l = `%c${dp}${connector}${lp} %c` + c.l
			c.colors = [pf, currentUserColorFormat, ...c.colors]
		}
		if (c.colors.length > 0) {
			currentUserColorFormat = c.colors[c.colors.length - 1]
		}
	}

	const finalContent = outputInfo.map(o => o.l).join('\n')
	const finalColors = outputInfo.flatMap(o => o.colors)
	file.write(new TextEncoder().encode(removeColorSpecifiers(finalContent, finalColors.length) + '\n'))
	rawConsole[level === 'timer'? 'log' : level](finalContent, ...finalColors)
}

for (const k of ['error', 'warn', 'log', 'info', 'debug'] as const) {
	globalThis.console[k] = (...data: any[]) => timestampedLeveledLog(k, data)
}

const timers: Record<string, number> = {}
globalThis.console.time = (label = 'default') => {
	if (timers[label])
		return console.warn(`Timer ${label} already exists.`, timers)
	timers[label] = performance.now()
}
globalThis.console.timeLog = (label = 'default', ...data: any[]) => {
	const logTime = performance.now()
	const startTime = timers[label]
	if (!startTime)
		return console.warn(`Timer ${label} doesn't exist.`, timers)
	timestampedLeveledLog('timer', [`${label}: ${(logTime - startTime).toLocaleString(undefined, { maximumFractionDigits: 0 })}ms`, ...data])
}
globalThis.console.timeEnd = (label = 'default') => {
	const endTime = performance.now()
	const startTime = timers[label]
	if (!startTime)
		return console.warn(`Timer ${label} doesn't exist.`, timers)
	timestampedLeveledLog('timer', [`${label}: ${(endTime - startTime).toLocaleString(undefined, { maximumFractionDigits: 0 })}ms - timer ended`])
	delete timers[label]
}

/** 
 * Set date format for timestamp prefix in log messages
 * Use following single character to represent date parts: y - year, m - month, d - day, H - hour, M - minute, S - second, T - millisecond
 * 
 * e.g. setDateFormat('y-m-d H:M:S.T')
 */
export function setDateFormat(fmt = 'y-m-d H:M:S.T') {
	config.dateFormat = fmt
}

/**
 * Whether to prefix log calls with no parameters, e.g. `console.log()`
 * Set this to `true` will keep writing prefix in this case
 * Set this to `false` will end up with a blank line
 * Default is `false`
 * Note: there will always be prefix for log calls with parameters, even this causes empty line, e.g. `console.log('')`
 */
export function prefixEmptyLines(p = false) {
	config.prefixEmptyLines = p
}

/**
 * Set colors for different log levels
 */
export function setColors(colors: Partial<typeof config.colors>) {
	Object.assign(config.colors, colors)
}

/**
 * Get the raw console object in case you need to use the original console
 */
export const raw = rawConsole