package main

import "core:fmt"
import "core:os"
import "core:os/os2"
import "core:strings"
import "core:strconv"
import "core:sys/windows"


dayrate : f64 = 3500
aliases : map[string]string
exe_dir : string
data_dir : string
alias_dir : string
ics_cache_dir : string

when ODIN_OS == .Windows {
	SEPARATOR :: "\\"
} else {
	SEPARATOR :: "/"
}

Arg_Type :: enum {
	NONE,
	FROM,
	TO,
	IN,
	SUBSTRING,
	ALIAS,
}
Arg_Flags :: bit_set[Arg_Type]

Range_Flags_Enum :: enum {
	YEAR,
	MONTH,
	DAY,
	HOUR,
	MINUTE,
}
Range_Flags :: bit_set[Range_Flags_Enum]

Filter :: struct {
	ranges : Range_Flags,
	time : Moment,
}

main :: proc() {
	when ODIN_OS == .Windows {
		windows.SetConsoleOutputCP(windows.CODEPAGE.UTF8)
	}
	exe_dir, _ = os2.get_executable_directory(context.allocator)
	data_dir      = fmt.tprint(exe_dir,  "statics_data",  sep = SEPARATOR)
	alias_dir     = fmt.tprint(data_dir, "aliases",       sep = SEPARATOR)
	ics_cache_dir = fmt.tprint(data_dir, "ics_cache",     sep = SEPARATOR)
	
	arg_count := len(os.args)-1
	filters : Arg_Flags = {}
	parsing : Arg_Type = .NONE
	
	verbose := false
	
	to_filter : Filter
	from_filter : Filter
	in_filter : Filter
	in_filter_out : Filter
	substring : string
	
	files_to_process : [dynamic]string
	
	flag_start := 0
	for &arg, i in os.args[1:] {
		if len(arg) == 2 {
			if arg[0] == '-' {
				flag_start = i
				break
			}
		}
		
		lower := strings.to_lower(arg, context.allocator)
		
		file_exists := os.is_file(arg)
		if file_exists {
			if lower[max(0, len(lower)-4):len(lower)] == ".ics" {
				append(&files_to_process, arg)
			} else {
				fmt.eprintln("ERROR: [{}] is not .ics file!", arg)
			}
		}
		if !file_exists {
			path := get_from_alias(arg)
			if path != "" {
				append(&files_to_process, path)
			} else {
				fmt.eprintfln("ERROR: [{}] is neither a file nor alias!", arg)
			}
		}
	}
	
	for &arg, i in os.args[flag_start:] {
		switch parsing {
			case .NONE:
				lower := strings.to_lower(arg, context.temp_allocator)
				switch lower {
					case "-t":
						parsing = .TO
					case "-f":
						parsing = .FROM
					case "-i":
						parsing = .IN
					case "-s":
						parsing = .SUBSTRING
					case "-v":
						verbose = true
					case "-h":
						fmt.println("statICS by Sander J. Skjegstad\n")
						
						fmt.println("Usage:")
						fmt.println("statics path/to/file.ics path/to/another_file.ics [FLAGS]")
						
						fmt.println("\nFlags:")
						fmt.println("\t-t     To: Filter up to and NOT including a specific time.")
						fmt.println("\t-f     From: Filter from and including a specific time.")
						fmt.println("\t-i     In: Filter to inside a specific year, month, etc.")
						fmt.println("\t-s     Substring: Case sensitive filter based on event names.")
						fmt.println("\t-a     Alias: Save an ICS URL to fetch via internet.")
						// TODO: fmt.println("\t-l     List: Lists saved aliases.")
						// TODO: fmt.println("\t-d     Delete: Deletes an alias.")
						fmt.println("\t-v     Verbose: Prints more info.")
						fmt.println("\t-h     Help: Show this screen.")
						
						fmt.println("\nFilter syntax:")
						fmt.println("Filters currently only filter based on the event start time.")
						fmt.println("Specify only as much as you want to filter by.")
						fmt.println("   YYYY-MM-DD-Hr-Mn")
						fmt.println("-t 2015-12-31-12-45 will not count anything from that point and out.")
						fmt.println("-i 2018-12 will only count things within December of 2018.")
						
						fmt.println("\nAlias syntax:")
						fmt.println("-a Project https://example.org/project.ics")
						fmt.println("This will save the URL under the alias Project.")
						fmt.println("Later you can then specify Project instead of a path/to/a_file.ics,")
						fmt.println("and it will fetch the ICS from the web via the saved link.")
						fmt.println("The URL and latest ICS from it will be stored next to the executable.")
						fmt.println("Depending on OS, be careful about special characters like / escaping.")
						
						fmt.println("")
						os.exit(0)
					case "-a":
						parsing = .ALIAS
				}
			case .FROM:
				text := strings.clone(arg)
				parse_to_filter(text, &from_filter)
				filters |= {.FROM}
				fmt.println("FROM filter set up from", momentToString(from_filter.time))
				parsing = .NONE
			case .TO:
				text := strings.clone(arg)
				parse_to_filter(text, &to_filter)
				filters |= {.TO}
				fmt.println("TO filter set up to", momentToString(to_filter.time))
				filter_maxx(&to_filter)
				parsing = .NONE
			case .IN:
				text := strings.clone(arg)
				parse_to_filter(text, &in_filter)
				in_filter_out = in_filter
				filter_maxx(&in_filter_out)
				filters |= {.IN}
				fmt.println("IN filter set up from", momentToString(in_filter.time), "to", momentToString(in_filter_out.time))
				parsing = .NONE
			case .SUBSTRING:
				substring = arg
				fmt.printfln("SUBSTRING filter set to \"{}\"", substring)
				filters |= {.SUBSTRING}
				parsing = .NONE
			case .ALIAS:
				@static alias_stage := 0
				@static alias_name := ""
				switch alias_stage {
					case 0:
						// Save name
						alias_name = arg
						alias_stage = 1
					case 1:
						save_alias(alias_name, arg)
						alias_stage = 0
						parsing = .NONE
				}
		}
	}
	
	
	total_minutes : int = 0;
	
	fmt.println()
	
	for file_path, i in files_to_process {
		
		fmt.printf("%d: ", i+1)
		fmt.println(file_path)
		
		timeblocks, ok := importICS(file_path)
		
		if ok {
			minutes : int = 0
			for each_block in timeblocks {
				pass := true
				pass_from      : bool = true
				pass_to        : bool = true
				pass_in        : bool = true
				pass_substring : bool = true
				if .FROM in filters {
					pass_from = greatEq(each_block.start, from_filter.time)
					pass &= pass_from
				}
				if .TO in filters {
					pass_to = lessEq(each_block.start, to_filter.time)
					pass &= pass_to
				}
				if .IN in filters {
					pass_in = lessEq(in_filter.time, each_block.start) && lessEq(each_block.start, in_filter_out.time)
					pass &= pass_in
				}
				if .SUBSTRING in filters {
					pass_substring = strings.contains(each_block.title, substring)
					pass &= pass_substring
				}
				icon := pass ? "✅" : "🚫"
				if verbose do fmt.println(icon, timeblockToString(each_block))
				if verbose && !pass_from      do fmt.println("   FILTERED by from-filter.")
				if verbose && !pass_to        do fmt.println("   FILTERED by to-filter.")
				if verbose && !pass_in        do fmt.println("   FILTERED by in-filter.")
				if verbose && !pass_substring do fmt.println("   FILTERED by substring-filter.")
				
				if !pass do continue
				
				minutes += minutecount(each_block)
			}
			display_minutes    : int = minutes%60
			display_hours      : int = (minutes-display_minutes)/60
			display_hour_count : f64 = f64(minutes)/60
			fmt.printf("     Hour count: %f\nHours & Minutes: %d:%02d\n\n",
				display_hour_count, display_hours, display_minutes)
			total_minutes += minutes
		} else {
			// Noffin i guess
			fmt.printf("\n\n")
		}
	}
	
	if len(files_to_process)>0 {
		fmt.println("\n------- SUM TOTAL -------")
		
		display_minutes    : int = total_minutes%60
		display_hours      : int = (total_minutes-display_minutes)/60
		display_hour_count : f64 = f64(total_minutes)/60
		
		fmt.printf("     Hour count: %f\nHours & Minutes: %d:%02d\n\n",
			display_hour_count, display_hours, display_minutes)
	}
	
	os.exit(0)
}


parse_to_filter :: proc(input : string, filter : ^Filter) {
	input := input
	i : int = 0
	ok : bool
	for substring in strings.split_iterator(&input, "-") {
		switch i {
			case 0:
				filter.time.year,    ok = strconv.parse_int(substring)
				if !ok {fmt.eprintln("ERROR: Failed to parse year:", substring)}
				filter.ranges |= {.YEAR}
			case 1:
				filter.time.month,   ok = strconv.parse_int(substring)
				if !ok {fmt.eprintln("ERROR: Failed to parse month:", substring)}
				filter.ranges |= {.MONTH}
			case 2:
				filter.time.day,     ok = strconv.parse_int(substring)
				if !ok {fmt.eprintln("ERROR: Failed to parse day:", substring)}
				filter.ranges |= {.DAY}
			case 3:
				filter.time.hours,   ok = strconv.parse_int(substring)
				if !ok {fmt.eprintln("ERROR: Failed to parse hours:", substring)}
				filter.ranges |= {.HOUR}
			case 4:
				filter.time.minutes, ok = strconv.parse_int(substring)
				if !ok {fmt.eprintln("ERROR: Failed to parse minutes:", substring)}
				filter.ranges |= {.MINUTE}
		}
		i += 1
		if !ok do os.exit(1)
	}
}

filter_maxx :: proc(filter : ^Filter) {
	// Super evil retarded bad hack, but it works!
	if .MONTH not_in filter.ranges { filter.time.month = 99 }
	if .DAY not_in filter.ranges { filter.time.day = 99 }
	if .HOUR not_in filter.ranges { filter.time.hours = 99 }
	if .MINUTE not_in filter.ranges { filter.time.minutes = 99 }
}


save_alias :: proc(name, url : string) -> bool {
	data := transmute([]u8)url
	
	output_file_path := fmt.tprint(alias_dir, name,      sep=SEPARATOR)
	
	just_fucking_make_the_directory(alias_dir)
	os.write_entire_file(output_file_path, data)
	
	fmt.printfln("Saved alias [%s -> %s] to: %s", name, url, output_file_path)
	return true
}

// Returns false if no aliases exist
load_aliases :: proc() -> bool {
	w := os2.walker_create(alias_dir)
	defer os2.walker_destroy(&w)
	
	found_alias := false
	
	for info in os2.walker_walk(&w) {
		if path, err := os2.walker_error(&w); err != nil {
			fmt.eprintfln("ERROR: Failed to walk %s: %s", path, err)
			continue
		}
		
		file_data, err := os2.read_entire_file_from_path(info.fullpath, allocator=context.allocator)
		if err != nil {
			fmt.eprintln("ERROR: Failed to load data from %s: %s", info.fullpath, err)
		} else {
			found_alias = true
			aliases[strings.clone(info.name, context.allocator)] = string(file_data)
		}
	}
	
	return found_alias
}

/*
This will return a path to a freshly downloaded ICS from an alias if it exists.
If the alias doesn't exist, the string will be empty.
*/
get_from_alias :: proc(alias : string) -> string {
	@static loaded := false
	if !loaded {
		aliases_exist := load_aliases()
		if !aliases_exist {
			return ""
		}
		loaded = true
	}
	
	url, ok := aliases[alias]
	if !ok {
		fmt.eprintfln("ERROR: Could not find alias '%s' among:", alias)
		i:=0
		for key, value in aliases {
			fmt.eprintfln(" %d: %s -> %s...", i, key, value[:min(len(value), 64)])
			i+=1
		}
		return ""
	}
	
	just_fucking_make_the_directory(ics_cache_dir)
	download_path := fmt.tprint(ics_cache_dir, SEPARATOR, alias, ".ics", sep="")
	dl_ok := download_file(url, download_path)
	
	if !dl_ok {
		fmt.eprintfln("ERROR: Failed to download '%s' from: %s", alias, url)
		return ""
	}
	
	return download_path
}


import "core:path/filepath"

// RECURSIVELY CREATES ANY DIRECTORY LIKE GOD INTENDED
just_fucking_make_the_directory :: proc(path : string) -> (directory_now_exists : bool) {
    path_clean := filepath.clean(path)
    
    if os.is_dir(path_clean) {
        return true
    }
    
    // Get parent directory
    parent := filepath.dir(path_clean)
    
    // If parent doesn't exist, create it recursively
    if parent != path_clean && !os.is_dir(parent) {
        ok := just_fucking_make_the_directory(parent)
        if !ok {
            return false
        }
    }
    
    err := os.make_directory(path_clean, 0o755)
    return err == os.ERROR_NONE
}




exec :: proc(command: ^[]string) -> bool {
	desc := os2.Process_Desc{
		command = command^,
		// Inherit parent's print pipes
		stdout = os2.stdout,
		stderr = os2.stderr,
		stdin = os2.stdin,
	}
	
	process, err := os2.process_start(desc)
	if err != nil {
		fmt.printf("Failed to start process: %v\n", err)
		return false
	}
	defer {
		if close_err := os2.process_close(process); close_err != nil {
			fmt.printf("Failed to close process: %v\n", close_err)
		}
	}
	
	state, wait_err := os2.process_wait(process)
	if wait_err != nil {
		fmt.printf("Error waiting for process: %v\n", wait_err)
		return false
	}
	
	return state.success && state.exit_code == 0
}

// TODO: Don't call out to the system's curl, ship my own
download_file :: proc(url: string, output_path: string) -> (ok: bool) {
    command : []string = {"curl", "-L", "-s", "-o", output_path, url}
	exec(&command)
	return os.exists(output_path)
}