#!/usr/bin/env python3
import argparse
import jinja2
import re

TEMPLATE = """\
///
///  Icon images.
///

//
//                     GENERATED BY xpm2rs.py -- DO NOT EDIT!
//
#[repr(u8)]
#[derive(Clone, Copy, Debug)]
pub enum XpmColor {
    Transparent = 0,
    Black = 1,
    White = 2,
}

#[derive(Clone)]
pub struct XpmImage {
    pub width: usize,
    pub height: usize,
    pub bitmap: &'static [XpmColor],
}

pub struct Icons {
{%- for icon in icons %}
    pub {{ icon.name }}: XpmImage,
{%- endfor %}
}

pub const ICONS: Icons = Icons {
{%- for icon in icons %}
{{ icon.comment }}
    {{ icon.name }}: XpmImage {
        width: {{ icon.width }},
        height: {{ icon.height }},
        #[rustfmt::skip]
        bitmap: &[
            {%- for bit in icon.bitmap -%}
                XpmColor::{{ bit }},
            {%- endfor -%}
        ],
    },
{%- endfor %}
};
"""

COLORS = {
    "black": "Black",
    "white": "White",
    "none": "Transparent",
}

def parse_xpm(xpm: str):
    state = "start"
    for line in xpm.splitlines():
        if state == "start":
            if m := re.match(r'static char \* (?P<name>.+)_xpm\[\] = {', line):
                name = m.groupdict()["name"]
                state = "size"
        elif state == "size":
            d = re.match(r'"(?P<width>\d+) (?P<height>\d+) (?P<num_colors>\d+) \d+",', line).groupdict()
            width = int(d["width"])
            height = int(d["height"])
            num_colors = int(d["num_colors"])
            height_remaining = height
            colors = {}
            state = "colors"
        elif state == "colors":
            d = re.match(r'"(?P<char>.)\tc (?P<color>[a-zA-Z]+)",', line).groupdict()
            colors[d["char"]] = COLORS[d["color"].lower()]
            num_colors -= 1
            if num_colors <= 0:
                bitmap = []
                comment = ""
                state = "bitmap"
        elif state == "bitmap":
            if height_remaining == 0:
                break
            else:
                for ch in re.match(r'"(?P<row>[^"]+)"(,|};)', line).groupdict()["row"]:
                    bitmap.append(colors[ch])
                    comment += ch
                comment += "\n"
                height_remaining -= 1
        else:
            assert "unreachable"

    return {
        "name": name,
        "width": width,
        "height": height,
        "bitmap": bitmap,
        "comment": "\n".join(map(lambda l: f"    // \"{l}\"", comment.strip("\n").splitlines())),
    }

def main():
    parser = argparse.ArgumentParser()
    parser.add_argument("xpm_files", nargs="+")
    args = parser.parse_args()

    icons = []
    for path in args.xpm_files:
        icons.append(parse_xpm(open(path).read()))

    print(jinja2.Template(TEMPLATE).render(icons=icons))


if __name__ == "__main__":
    main()