const std = @import("std");

const Allocator = std.mem.Allocator;

pub fn resolvePath(allocator: Allocator, name: []const u8) ![]u8 {
    return std.fs.cwd().realpathAlloc(allocator, name) catch |err| switch (err) {
        error.FileNotFound => if (name.len == 0) {
            return error.FileNotFound;
        } else if (name[0] == std.fs.path.sep) {
            // Already is an absolute path
            return allocator.dupe(u8, name);
        } else if (name[0] == '~') {
            if (name.len == 1) {
                return error.FileNotFound;
            } else if (name[1] == std.fs.path.sep) {
                var env_map = try std.process.getEnvMap(allocator);
                defer env_map.deinit();

                if (env_map.get("HOME")) |home| {
                    return try std.fs.path.join(allocator, &.{ home, name[2..] });
                } else {
                    std.log.err("No $HOME environment variable available!", .{});
                    return error.FileNotFound;
                }
            } else {
                // TODO: Currently only doing ~/paths no ~user/paths
                return error.FileNotFound;
            }
        } else {
            const cwd = try std.process.getCwdAlloc(allocator);
            defer allocator.free(cwd);

            return std.fmt.allocPrint(allocator, "{s}{s}{s}", .{cwd, std.fs.path.sep_str, name});
        },
        else => return err,
    };
}