const std = @import("std");

pub const Config = struct {
    listen_host: []const u8,
    listen_port: u16,
    cache_size: usize,
    cache_dir: []const u8,
    geolite_path: []const u8,
    geocache_file: ?[]const u8,

    pub fn load(allocator: std.mem.Allocator) !Config {
        var env = try std.process.getEnvMap(allocator);
        defer env.deinit();
        return Config{
            .listen_host = env.get("WTTR_LISTEN_HOST") orelse try allocator.dupe(u8, "0.0.0.0"),
            .listen_port = if (env.get("WTTR_LISTEN_PORT")) |p|
                try std.fmt.parseInt(u16, p, 10)
            else
                8002,
            .cache_size = if (env.get("WTTR_CACHE_SIZE")) |s|
                try std.fmt.parseInt(usize, s, 10)
            else
                10_000,
            .cache_dir = try allocator.dupe(u8, env.get("WTTR_CACHE_DIR") orelse "/tmp/wttr-cache"),
            .geolite_path = try allocator.dupe(u8, env.get("WTTR_GEOLITE_PATH") orelse "./GeoLite2-City.mmdb"),
            .geocache_file = if (env.get("WTTR_GEOCACHE_FILE")) |v| try allocator.dupe(u8, v) else null,
        };
    }

    pub fn deinit(self: Config, allocator: std.mem.Allocator) void {
        allocator.free(self.listen_host);
        allocator.free(self.cache_dir);
        allocator.free(self.geolite_path);
        if (self.geocache_file) |f| allocator.free(f);
    }
};

test "config loads defaults" {
    const allocator = std.testing.allocator;
    const cfg = try Config.load(allocator);
    defer cfg.deinit(allocator);

    try std.testing.expectEqualStrings("0.0.0.0", cfg.listen_host);
    try std.testing.expectEqual(@as(u16, 8002), cfg.listen_port);
    try std.testing.expectEqual(@as(usize, 10_000), cfg.cache_size);
    try std.testing.expectEqualStrings("./GeoLite2-City.mmdb", cfg.geolite_path);
    try std.testing.expect(cfg.geocache_file == null);
}