const std = @import("std");
const Dir = std.Io.Dir;

const elfy = @import("elfy");
const mvzr = @import("mvzr");

pub fn main(init: std.process.Init) !void {
    var gpa: std.heap.DebugAllocator(.{}) = .init;
    const allocator = gpa.allocator();
    defer _ = gpa.deinit();

    const args = try init.minimal.args.toSlice(init.arena.allocator());

    if (args.len != 5) {
        std.debug.print("Usage: {s} <source_file> <pattern> <prefix> <output_file>\n", .{args[0]});
        std.process.exit(1);
    }
    const input_path = args[1];
    const pattern = args[2];
    const prefix = args[3];
    const output_path = args[4];
    const re = mvzr.compile(pattern) orelse @panic("Failed to compile regex pattern");
    
    var file = try Dir.cwd().createFile(init.io, output_path, .{ .truncate = true });
    defer file.close(init.io);
    var w = file.writer(init.io, &[0]u8{});
    
    _ = try w.interface.write("/* Auto-generated symbol extract header */\n#pragma once\n");
    var binary = try elfy.Elf.init(init.io, input_path, .ReadOnly, allocator);
    defer binary.deinit();

    var symbols = try binary.getIterator(elfy.ElfSymbol);
    while (try symbols.next()) |symbol| {
        const name = try binary.getSymbolName(symbol);
        if (re.isMatch(name)) {
            try w.interface.print("#define {s}{s} 0x{x}\n", .{prefix, name, symbol.getValue()});
        }
    }
    try w.interface.flush();
}