package main

import math "core:math"
import "core:fmt"
import "core:strings"
import "core:strconv"
import "core:slice"

//
// --- STRUCTURES ---
//

Weekday : enum{
	Monday,
	Tuesday,
	Wednesday,
	Thursday,
	Friday,
	Saturday,
	Sunday
}

Delta :: struct {
	minutes : int,
	hours   : int,
	days    : int,
}

Moment :: struct {
	minutes : int,
	hours   : int,
	day     : int,
	month   : int,
	year    : int,
}

Timeblock :: struct {
	start : Moment,
	end   : Moment,
	valuefactor : f32,
	price_reason : string,
}

Workday :: struct {
	call		 : Moment,
	wrap		 : Moment,
	planned_wrap : Moment,
	
	blocks : [15]Timeblock,
	total_timeblocks : int,
}

//
// --- BASIC OPERATIONS ---
//

windIndividual :: proc(input_moment: ^Moment,
			 minutes:	int,
			 hours: 	int,
			 days:		int) {
	
	// Adding minutes
	input_moment.minutes += minutes
	for input_moment.minutes > 59 {
		input_moment.minutes -= 60
		input_moment.hours += 1
	}
	for input_moment.minutes < 0 {
		input_moment.minutes += 60
		input_moment.hours -= 1
	}
	
	// Adding hours
	input_moment.hours += hours
	for input_moment.hours > 23 {
		input_moment.hours -= 24
		input_moment.day += 1
	}
	for input_moment.hours < 0 {
		input_moment.hours += 24
		input_moment.day -= 1
	}
	
	// Adding days
	input_moment.day += days
	current_month_length: int = days_in(input_moment.month, input_moment.year)
	
	for input_moment.day > current_month_length {
		input_moment.day -= current_month_length
		input_moment.month += 1
		if input_moment.month > 12 {
			input_moment.month -= 12
			input_moment.year += 1
		}
		current_month_length = days_in(input_moment.month, input_moment.year)
	}
	
	for input_moment.day < 1 {
		input_moment.month -= 1
		if input_moment.month < 1 {
			input_moment.month += 12
			input_moment.year -= 1
		}
		current_month_length = days_in(input_moment.month, input_moment.year)
		input_moment.day += current_month_length
	}
	
	return
}
windDelta :: proc(moment: ^Moment, delta: Delta) {
	using delta
	wind(moment, minutes, hours, days)
	return
}
wind :: proc{windIndividual, windDelta}


add :: proc(moment: Moment, delta: Delta) -> (output: Moment) {
	output = moment
	wind(&output, delta)
	return
}
sub :: proc(moment: Moment, delta: Delta) -> (output: Moment) {
	output = moment
	using delta
	wind(&output, minutes*-1, hours*-1, days*-1)
	return
}

gtMoment :: proc(moment_a: Moment, moment_b: Moment) -> bool {
	// TODO: This is wrong
	return true
}
gtDelta :: proc(delta_a: Delta, delta_b: Delta) -> bool {
	// TODO: This is wrong
	return true
}
gt :: proc{gtMoment, gtDelta}

diff :: proc(moment_a: Moment, moment_b: Moment) -> (acc: Delta) {
	
	acc = {0, 0, 0}
	if moment_a == moment_b do return
	
	// Uses what I call an accumulator-decumulator design
	// Count how long it takes to approach a benchmark,
	// and that count is the difference
	
	reverse: bool = gt(moment_b, moment_a)
	
	
	// TODO: Finish writing this
	
	
	return
}

sortableTimeDelta :: proc(delta: Delta) -> int {
	using delta
	return strconv.atoi(fmt.tprintf("%2i%2i%2i", days, hours, minutes))
}
sortableTimeMoment :: proc(moment: Moment) -> int {
	using moment
	return strconv.atoi(fmt.tprintf("%4i%2i%2i%2i%2i", year, month, day, hours, minutes))
}

deltaToString :: proc(delta: Delta) -> (output: string) {
	using delta
	
	if hours == 0 &&
	   days == 0 &&
	   minutes == 0 {
			return "None"
	   }
	
	cat_array : [dynamic]string
	printed_prev : bool = false
	
	if days>0 {
		buf: [5]byte
		append(&cat_array, fmt.tprint(days))
		if days < 2 {
			append(&cat_array, " day")
		} else {
			append(&cat_array, " days")
		}
		printed_prev = true
	}
	
	if hours>0 {
		
		if printed_prev do append(&cat_array, ", ")
		
		buf: [5]byte
		append(&cat_array, fmt.tprint(hours))
		if hours < 2 {
			append(&cat_array, " hour")
		} else {
			append(&cat_array, " hours")
		}
		printed_prev = true
	}
	
	if minutes>0 {
		
		if printed_prev do append(&cat_array, ", ")
		
		buf: [5]byte
		append(&cat_array, fmt.tprint(minutes))
		if minutes < 2 {
			append(&cat_array, " minute")
		} else {
			append(&cat_array, " minutes")
		}
	}
	
	output = strings.concatenate(cat_array[:])
	return
	
}


momentToString :: proc(moment: Moment) -> (output: string) {
	using moment
	
	cat_array: [dynamic]string
	
	output = fmt.tprintf("%i-%2i-%2i %2i:%2i", year, month, day, hours, minutes)
	
	return
}
timeblockToString :: proc(block: Timeblock) -> (output: string) {
	using block
	s: [3]string = {toString(start), " -> ", toString(end)}
	output = strings.concatenate(s[:])
	return
}
toString :: proc{deltaToString, momentToString, timeblockToString}



clockprintMoment :: proc(moment: Moment) -> string {
	using moment
	return fmt.tprintf("%2i:%2i", hours, minutes)
}
clockprintTimeblock :: proc(block: Timeblock) -> string {
	using block
	return fmt.tprintf("%s -> %s", timeprint(start), timeprint(end))
}
timeprint :: proc{clockprintTimeblock, clockprintMoment}


//
// --- PROCEDURES ---
//

days_in :: proc(month: int, year: int) -> int {
	switch month {
		case 1:
			return 31;
		case 2:
			if (((year % 4 == 0) && (year % 100 != 0)) || (year % 400 == 0)){
				return 29;
			}
			return 28;
		case 3:
			return 31;
		case 4:
			return 30;
		case 5:
			return 31;
		case 6:
			return 30;
		case 7:
			return 31;
		case 8:
			return 31;
		case 9:
			return 30;
		case 10:
			return 31;
		case 11:
			return 30;
		case 12:
			return 31;
	}
	fmt.printf("You just found month nr: %i. Something is very wrong.\n", month)
	assert(month < 13 &&  month > 0)
	return 30
}

new_workday :: proc(previous_wrap    : Moment,
					calltime         : Moment,
					wraptime         : Moment,
					planned_wraptime : Moment) -> (workday: Workday) {
	
	workday.call = calltime
	workday.wrap = wraptime
	workday.planned_wrap = planned_wraptime
	
	/*
	initial_block: Timeblock = {
		math.max(
			math.clamp(),
			)
	}
	*/
	
	return
}