package main

import "core:c"
import "core:fmt"
import "core:os"
import "core:strconv"
import "core:strings"

PPM_MAGIC_NUMBER :: enum {
	P6,
	P3,
}

Ppm_file :: struct {
	magic_num: PPM_MAGIC_NUMBER,
	width:     int,
	height:    int,
	data:      []byte,
}

load_ppm :: proc(ppm_file: ^Ppm_file, filename: string) -> (success: bool) {
	if !strings.has_suffix(filename, ".ppm") {
		fmt.eprintfln("ERROR: File %s does not have a valid ppm extention (.ppm)", filename)
		return false
	}

	succ: bool
	ppm_file.data, succ = os.read_entire_file_from_filename(filename, context.temp_allocator)
	if !succ {
		fmt.eprintfln("ERROR: Failed to load file: %s ", filename)
		return false
	}
	return true
}

ppm_parse :: proc(ppm_file: ^Ppm_file) {

	it := string(ppm_file.data)
	for line in strings.split_lines_iterator(&it) {
		if strings.starts_with(line, "#") {continue} 	//ignore comments
		if strings.starts_with(line, "P") {
			num, _ := strconv.parse_int(strings.trim(line, "P"))
			if num == 3 {
				ppm_file.magic_num = .P3
			} else if num == 6 {
				ppm_file.magic_num = .P6
			}
		}

		w_h_parts := strings.split(line, " ")
		if len(w_h_parts) == 2 {
			ppm_file.width, _ = strconv.parse_int(w_h_parts[0])
			ppm_file.height, _ = strconv.parse_int(w_h_parts[1])

		}
	}
}