package main

import "core:fmt"
import "core:os"
import "core:sys/unix"

foreign import libc "system:c"

// Terminal codes
CLEAR_CODE  :: "\033[2J"
HIDE_CURSOR :: "\033[?25l"
RESET       :: "\0033[0m"

TIOCGWINSZ :: 0x5413

winsize :: struct {
    ws_row: u16,
    ws_col: u16,
    ws_xpixel: u16,
    ws_ypixel: u16,
}

@(default_calling_convention="c")
foreign libc {
    ioctl  :: proc(fd: i32, request: u64, #c_vararg args: ..any) -> i32 ---
    signal :: proc(signum: i32, handler: proc "c" (i32)) -> rawptr ---
}

SIGWINCH :: 28

resize_occurred := false

signal_handler :: proc "c" (sig: i32) {
    resize_occurred = true
}

get_terminal_size :: proc() -> (rows, cols: int, ok: bool) {
    ws: winsize

    result := ioctl(i32(os.stdout), TIOCGWINSZ, &ws)

    if result == -1 {
        return 0, 0, false
    }

    return int(ws.ws_row), int(ws.ws_col), true
}

main :: proc() {
    signal(SIGWINCH, signal_handler)

	if len(os.args) != 2 {
		fmt.eprintln("INCORRECT NUMBER OF COMMAND LINE ARGUMENTS")
		return
	}

	filename := os.args[1]
	data, ok := os.read_entire_file_from_filename(os.args[1])
	if !ok {
		fmt.eprintfln("ERROR: failed to open file: %s", filename)
	}

    for {
        if resize_occurred {
            resize_occurred = false
            rows, cols, ok := get_terminal_size()
            if ok {
                fmt.printf("Terminal resized! New size: %d rows x %d cols\n", rows, cols)
            }
        }
    }
}