more AI implementation

zig/build.zig

@@ -9,6 +9,43 @@ pub fn build(b: *std.Build) void {
         .optimize = optimize,
     });
 
+    const maxminddb_upstream = b.dependency("maxminddb", .{});
+
+    // Build libmaxminddb as a static library
+    const maxminddb = b.addLibrary(.{
+        .name = "maxminddb",
+        .linkage = .static,
+        .root_module = b.createModule(.{
+            .target = target,
+            .optimize = optimize,
+            .link_libc = true,
+        }),
+    });
+
+    // Generate maxminddb_config.h
+    const maxminddb_config = b.addConfigHeader(.{
+        .style = .blank,
+        .include_path = "maxminddb_config.h",
+    }, .{
+        .PACKAGE_VERSION = "1.11.0",
+        .MMDB_UINT128_USING_MODE = 1,
+    });
+
+    maxminddb.addConfigHeader(maxminddb_config);
+    maxminddb.addIncludePath(maxminddb_upstream.path("include"));
+    maxminddb.addIncludePath(maxminddb_upstream.path("src"));
+
+    maxminddb.addCSourceFiles(.{
+        .root = maxminddb_upstream.path(""),
+        .files = &.{
+            "src/data-pool.c",
+            "src/maxminddb.c",
+        },
+        .flags = &.{},
+    });
+
+    maxminddb.installHeadersDirectory(maxminddb_upstream.path("include"), "", .{});
+
     const exe = b.addExecutable(.{
         .name = "wttr",
         .root_module = b.createModule(.{
@@ -19,6 +56,7 @@ pub fn build(b: *std.Build) void {
     });
 
     exe.root_module.addImport("httpz", httpz.module("httpz"));
+    exe.linkLibrary(maxminddb);
     exe.linkLibC();
 
     b.installArtifact(exe);
@@ -40,6 +78,7 @@ pub fn build(b: *std.Build) void {
         }),
     });
     tests.root_module.addImport("httpz", httpz.module("httpz"));
+    tests.linkLibrary(maxminddb);
     tests.linkLibC();
 
     const run_tests = b.addRunArtifact(tests);

zig/build.zig.zon

@@ -6,6 +6,10 @@
             .url = "https://github.com/karlseguin/http.zig/archive/refs/heads/master.tar.gz",
             .hash = "httpz-0.0.0-PNVzrEktBwCzPoiua-S8LAYo2tILqczm3tSpneEzLQ9L",
         },
+        .maxminddb = .{
+            .url = "https://github.com/maxmind/libmaxminddb/archive/refs/tags/1.11.0.tar.gz",
+            .hash = "N-V-__8AAAYyBQCd9x7qVVFKQIxi01UZ1K8ZFZFfTzj99CvX",
+        },
     },
     .fingerprint = 0x710c2b57e81aa678,
     .minimum_zig_version = "0.15.0",

zig/src/config.zig

@@ -34,3 +34,15 @@ pub const Config = struct {
         allocator.free(self.geolocator_url);
     }
 };
+
+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.expectEqualStrings("http://localhost:8004", cfg.geolocator_url);
+}

zig/src/http/handler.zig

@@ -4,6 +4,7 @@ const Cache = @import("../cache/cache.zig").Cache;
 const WeatherProvider = @import("../weather/provider.zig").WeatherProvider;
 const ansi = @import("../render/ansi.zig");
 const line = @import("../render/line.zig");
+const help = @import("help.zig");
 
 pub const HandleWeatherOptions = struct {
     cache: *Cache,
@@ -24,6 +25,20 @@ pub fn handleWeatherLocation(
     res: *httpz.Response,
 ) !void {
     const location = req.param("location") orelse "London";
+
+    // Handle special endpoints
+    if (std.mem.startsWith(u8, location, ":")) {
+        if (std.mem.eql(u8, location, ":help")) {
+            res.content_type = .TEXT;
+            res.body = help.help_page;
+            return;
+        } else if (std.mem.eql(u8, location, ":translation")) {
+            res.content_type = .TEXT;
+            res.body = help.translation_page;
+            return;
+        }
+    }
+
     try handleWeatherInternal(opts, req, res, location);
 }
 
@@ -44,7 +59,20 @@ fn handleWeatherInternal(
     }
 
     const loc = location orelse "London";
-    const weather = try opts.provider.fetch(allocator, loc);
+    const weather = opts.provider.fetch(allocator, loc) catch |err| {
+        switch (err) {
+            error.LocationNotFound => {
+                res.status = 404;
+                res.body = "Location not found\n";
+                return;
+            },
+            else => {
+                res.status = 500;
+                res.body = "Internal server error\n";
+                return;
+            },
+        }
+    };
     defer weather.deinit();
 
     const query = try req.query();

zig/src/http/help.zig

@@ -0,0 +1,55 @@
+const std = @import("std");
+
+pub const help_page =
+    \\wttr.in - Weather Forecast Service
+    \\
+    \\Usage:
+    \\  curl wttr.in                  # Weather for your location
+    \\  curl wttr.in/London           # Weather for London
+    \\  curl wttr.in/~Eiffel+Tower    # Weather for special location
+    \\  curl wttr.in/@github.com      # Weather for domain location
+    \\  curl wttr.in/muc              # Weather for airport (IATA code)
+    \\
+    \\Query Parameters:
+    \\  ?format=FORMAT    Output format (1,2,3,4,j1,p1,v2)
+    \\  ?lang=LANG        Language code (en,de,fr,etc)
+    \\  ?u                Use USCS units
+    \\  ?m                Use metric units
+    \\  ?t                Transparency for PNG
+    \\
+    \\Special Endpoints:
+    \\  /:help            This help page
+    \\  /:translation     Translation information
+    \\
+    \\Examples:
+    \\  curl wttr.in/Paris?format=3
+    \\  curl wttr.in/Berlin?lang=de
+    \\  curl wttr.in/Tokyo?m
+    \\
+    \\For more information visit: https://github.com/chubin/wttr.in
+    \\
+;
+
+pub const translation_page =
+    \\wttr.in Translation
+    \\
+    \\wttr.in is currently translated into 54 languages.
+    \\
+    \\Language Support:
+    \\  - Automatic detection via Accept-Language header
+    \\  - Manual selection via ?lang=CODE parameter
+    \\  - Subdomain selection (e.g., de.wttr.in)
+    \\
+    \\Contributing:
+    \\  To help translate wttr.in, visit:
+    \\  https://github.com/chubin/wttr.in
+    \\
+;
+
+test "help page exists" {
+    try std.testing.expect(help_page.len > 0);
+}
+
+test "translation page exists" {
+    try std.testing.expect(translation_page.len > 0);
+}

zig/src/location/geoip.zig

@@ -0,0 +1,148 @@
+const std = @import("std");
+
+pub const Coordinates = struct {
+    latitude: f64,
+    longitude: f64,
+};
+
+pub const MMDB = extern struct {
+    filename: [*:0]const u8,
+    flags: u32,
+    file_content: ?*anyopaque,
+    file_size: usize,
+    data_section: ?*anyopaque,
+    data_section_size: u32,
+    metadata_section: ?*anyopaque,
+    metadata_section_size: u32,
+    full_record_byte_size: u16,
+    depth: u16,
+    ipv4_start_node: extern struct {
+        node_value: u32,
+        netmask: u16,
+    },
+    metadata: extern struct {
+        node_count: u32,
+        record_size: u16,
+        ip_version: u16,
+        database_type: [*:0]const u8,
+        languages: extern struct {
+            count: usize,
+            names: [*][*:0]const u8,
+        },
+        binary_format_major_version: u16,
+        binary_format_minor_version: u16,
+        build_epoch: u64,
+        description: extern struct {
+            count: usize,
+            descriptions: [*]?*anyopaque,
+        },
+    },
+};
+
+pub const MMDBLookupResult = extern struct {
+    found_entry: bool,
+    entry: MMDBEntry,
+    netmask: u16,
+};
+
+pub const MMDBEntry = extern struct {
+    mmdb: *MMDB,
+    offset: u32,
+};
+
+pub const MMDBEntryData = extern struct {
+    has_data: bool,
+    data_type: u32,
+    offset: u32,
+    offset_to_next: u32,
+    data_size: u32,
+    utf8_string: [*:0]const u8,
+    double_value: f64,
+    bytes: [*]const u8,
+    uint16: u16,
+    uint32: u32,
+    int32: i32,
+    uint64: u64,
+    uint128: u128,
+    boolean: bool,
+    float_value: f32,
+};
+
+extern fn MMDB_open(filename: [*:0]const u8, flags: u32, mmdb: *MMDB) c_int;
+extern fn MMDB_close(mmdb: *MMDB) void;
+extern fn MMDB_lookup_string(mmdb: *MMDB, ipstr: [*:0]const u8, gai_error: *c_int, mmdb_error: *c_int) MMDBLookupResult;
+extern fn MMDB_get_value(entry: *MMDBEntry, entry_data: *MMDBEntryData, ...) c_int;
+extern fn MMDB_strerror(error_code: c_int) [*:0]const u8;
+
+pub const GeoIP = struct {
+    mmdb: MMDB,
+
+    pub fn init(db_path: []const u8) !GeoIP {
+        var mmdb: MMDB = undefined;
+        const path_z = try std.heap.c_allocator.dupeZ(u8, db_path);
+        defer std.heap.c_allocator.free(path_z);
+
+        const status = MMDB_open(path_z.ptr, 0, &mmdb);
+        if (status != 0) {
+            return error.CannotOpenDatabase;
+        }
+
+        return GeoIP{ .mmdb = mmdb };
+    }
+
+    pub fn deinit(self: *GeoIP) void {
+        MMDB_close(&self.mmdb);
+    }
+
+    pub fn lookup(self: *GeoIP, ip: []const u8) !?Coordinates {
+        const ip_z = try std.heap.c_allocator.dupeZ(u8, ip);
+        defer std.heap.c_allocator.free(ip_z);
+
+        var gai_error: c_int = 0;
+        var mmdb_error: c_int = 0;
+
+        const result = MMDB_lookup_string(&self.mmdb, ip_z.ptr, &gai_error, &mmdb_error);
+
+        if (gai_error != 0 or mmdb_error != 0) {
+            return null;
+        }
+
+        if (!result.found_entry) {
+            return null;
+        }
+
+        return try self.extractCoordinates(result.entry);
+    }
+
+    fn extractCoordinates(self: *GeoIP, entry: MMDBEntry) !Coordinates {
+        _ = self;
+        var entry_mut = entry;
+        var latitude_data: MMDBEntryData = undefined;
+        var longitude_data: MMDBEntryData = undefined;
+
+        const lat_path = [_][*:0]const u8{ "location", "latitude", null };
+        const lon_path = [_][*:0]const u8{ "location", "longitude", null };
+
+        const lat_status = MMDB_get_value(&entry_mut, &latitude_data, lat_path[0], lat_path[1], lat_path[2]);
+        const lon_status = MMDB_get_value(&entry_mut, &longitude_data, lon_path[0], lon_path[1], lon_path[2]);
+
+        if (lat_status != 0 or lon_status != 0 or !latitude_data.has_data or !longitude_data.has_data) {
+            return error.CoordinatesNotFound;
+        }
+
+        return Coordinates{
+            .latitude = latitude_data.double_value,
+            .longitude = longitude_data.double_value,
+        };
+    }
+};
+
+test "MMDB functions are callable" {
+    const mmdb_error = MMDB_strerror(0);
+    try std.testing.expect(mmdb_error[0] != 0);
+}
+
+test "GeoIP init with invalid path fails" {
+    const result = GeoIP.init("/nonexistent/path.mmdb");
+    try std.testing.expectError(error.CannotOpenDatabase, result);
+}

zig/src/location/resolver.zig

@@ -0,0 +1,171 @@
+const std = @import("std");
+const GeoIP = @import("geoip.zig").GeoIP;
+
+pub const Location = struct {
+    name: []const u8,
+    latitude: f64,
+    longitude: f64,
+};
+
+pub const LocationType = enum {
+    city_name,
+    airport_code,
+    special_location,
+    ip_address,
+    domain_name,
+};
+
+pub const Resolver = struct {
+    allocator: std.mem.Allocator,
+    geoip: ?*GeoIP,
+    geolocator_url: []const u8,
+
+    pub fn init(allocator: std.mem.Allocator, geoip: ?*GeoIP, geolocator_url: []const u8) Resolver {
+        return .{
+            .allocator = allocator,
+            .geoip = geoip,
+            .geolocator_url = geolocator_url,
+        };
+    }
+
+    pub fn resolve(self: *Resolver, query: []const u8) !Location {
+        const location_type = detectType(query);
+
+        return switch (location_type) {
+            .ip_address => try self.resolveIP(query),
+            .domain_name => try self.resolveDomain(query[1..]), // Skip '@'
+            .special_location => try self.resolveGeocoded(query[1..]), // Skip '~'
+            .airport_code => try self.resolveAirport(query),
+            .city_name => try self.resolveGeocoded(query),
+        };
+    }
+
+    fn detectType(query: []const u8) LocationType {
+        if (query.len == 0) return .city_name;
+        if (query[0] == '@') return .domain_name;
+        if (query[0] == '~') return .special_location;
+        if (query.len == 3 and isAlpha(query)) return .airport_code;
+        if (isIPAddress(query)) return .ip_address;
+        return .city_name;
+    }
+
+    fn resolveIP(self: *Resolver, ip: []const u8) !Location {
+        if (self.geoip) |geoip| {
+            if (try geoip.lookup(ip)) |coords| {
+                return Location{
+                    .name = try self.allocator.dupe(u8, ip),
+                    .latitude = coords.latitude,
+                    .longitude = coords.longitude,
+                };
+            }
+        }
+        return error.LocationNotFound;
+    }
+
+    fn resolveDomain(self: *Resolver, domain: []const u8) !Location {
+        // Use std.net to resolve domain to IP
+        const addr_list = std.net.getAddressList(self.allocator, domain, 0) catch {
+            return error.LocationNotFound;
+        };
+        defer addr_list.deinit();
+
+        if (addr_list.addrs.len == 0) {
+            return error.LocationNotFound;
+        }
+
+        // Format IP address
+        const ip_str = try std.fmt.allocPrint(self.allocator, "{}", .{addr_list.addrs[0].any});
+        defer self.allocator.free(ip_str);
+
+        return self.resolveIP(ip_str);
+    }
+
+    fn resolveGeocoded(self: *Resolver, name: []const u8) !Location {
+        // Call external geocoding service
+        const client = std.http.Client{ .allocator = self.allocator };
+        defer client.deinit();
+
+        const url = try std.fmt.allocPrint(
+            self.allocator,
+            "{s}/geocode?q={s}",
+            .{ self.geolocator_url, name },
+        );
+        defer self.allocator.free(url);
+
+        var response = std.ArrayList(u8).init(self.allocator);
+        defer response.deinit();
+
+        const result = client.fetch(.{
+            .location = .{ .url = url },
+            .response_storage = .{ .dynamic = &response },
+        }) catch {
+            return error.GeocodingFailed;
+        };
+
+        if (result.status != .ok) {
+            return error.LocationNotFound;
+        }
+
+        // Parse JSON response: {"name": "...", "lat": ..., "lon": ...}
+        const parsed = std.json.parseFromSlice(
+            struct { name: []const u8, lat: f64, lon: f64 },
+            self.allocator,
+            response.items,
+            .{},
+        ) catch {
+            return error.InvalidGeocodingResponse;
+        };
+        defer parsed.deinit();
+
+        return Location{
+            .name = try self.allocator.dupe(u8, parsed.value.name),
+            .latitude = parsed.value.lat,
+            .longitude = parsed.value.lon,
+        };
+    }
+
+    fn resolveAirport(self: *Resolver, code: []const u8) !Location {
+        // For now, treat as geocoded location
+        return self.resolveGeocoded(code);
+    }
+
+    fn isAlpha(s: []const u8) bool {
+        for (s) |c| {
+            if (!std.ascii.isAlphabetic(c)) return false;
+        }
+        return true;
+    }
+
+    fn isIPAddress(s: []const u8) bool {
+        // Simple check for IPv4
+        var dots: u8 = 0;
+        for (s) |c| {
+            if (c == '.') {
+                dots += 1;
+            } else if (!std.ascii.isDigit(c)) {
+                return false;
+            }
+        }
+        return dots == 3;
+    }
+};
+
+test "detect IP address" {
+    try std.testing.expect(Resolver.isIPAddress("192.168.1.1"));
+    try std.testing.expect(!Resolver.isIPAddress("not.an.ip"));
+}
+
+test "detect location type" {
+    try std.testing.expectEqual(LocationType.ip_address, Resolver.detectType("8.8.8.8"));
+    try std.testing.expectEqual(LocationType.domain_name, Resolver.detectType("@github.com"));
+    try std.testing.expectEqual(LocationType.special_location, Resolver.detectType("~Eiffel+Tower"));
+    try std.testing.expectEqual(LocationType.airport_code, Resolver.detectType("muc"));
+    try std.testing.expectEqual(LocationType.city_name, Resolver.detectType("London"));
+}
+
+test "resolver init" {
+    const allocator = std.testing.allocator;
+    const resolver = Resolver.init(allocator, null, "http://localhost:8004");
+    try std.testing.expect(resolver.geoip == null);
+    try std.testing.expectEqualStrings("http://localhost:8004", resolver.geolocator_url);
+}

zig/src/main.zig

@@ -5,6 +5,7 @@ const MetNo = @import("weather/metno.zig").MetNo;
 const types = @import("weather/types.zig");
 const Server = @import("http/server.zig").Server;
 const RateLimiter = @import("http/rate_limiter.zig").RateLimiter;
+const GeoIP = @import("location/geoip.zig").GeoIP;
 
 pub const std_options: std.Options = .{
     .log_level = .info,
@@ -25,8 +26,17 @@ pub fn main() !void {
     try stdout.print("wttr starting on {s}:{d}\n", .{ cfg.listen_host, cfg.listen_port });
     try stdout.print("Cache size: {d}\n", .{cfg.cache_size});
     try stdout.print("Cache dir: {s}\n", .{cfg.cache_dir});
+    try stdout.print("GeoLite2 path: {s}\n", .{cfg.geolite_path});
     try stdout.flush();
 
+    // Initialize GeoIP database
+    var geoip = GeoIP.init(cfg.geolite_path) catch |err| {
+        std.log.warn("Failed to load GeoIP database: {}", .{err});
+        std.log.warn("IP-based location resolution will be unavailable", .{});
+        return err;
+    };
+    defer geoip.deinit();
+
     var cache = try Cache.init(allocator, .{
         .max_entries = cfg.cache_size,
         .cache_dir = cfg.cache_dir,
@@ -53,8 +63,13 @@ pub fn main() !void {
 
 test {
     std.testing.refAllDecls(@This());
+    _ = @import("config.zig");
     _ = @import("cache/lru.zig");
     _ = @import("weather/mock.zig");
     _ = @import("http/rate_limiter.zig");
+    _ = @import("http/query.zig");
+    _ = @import("http/help.zig");
     _ = @import("render/line.zig");
+    _ = @import("location/geoip.zig");
+    _ = @import("location/resolver.zig");
 }

zig/src/render/json.zig

@@ -1,11 +1,73 @@
 const std = @import("std");
 const types = @import("../weather/types.zig");
 
-pub fn render(allocator: std.mem.Allocator, data: types.WeatherData) ![]const u8 {
-    var output: std.ArrayList(u8) = .empty;
-    errdefer output.deinit(allocator);
+pub fn render(allocator: std.mem.Allocator, weather: types.WeatherData) ![]const u8 {
+    var output = std.ArrayList(u8).init(allocator);
+    errdefer output.deinit();
 
-    try std.json.stringify(data, .{}, output.writer(allocator));
+    try std.json.stringify(.{
+        .current_condition = .{
+            .temp_C = weather.current.temp_c,
+            .temp_F = weather.current.temp_f,
+            .weatherCode = weather.current.weather_code,
+            .weatherDesc = .{.{ .value = weather.current.condition }},
+            .humidity = weather.current.humidity,
+            .windspeedKmph = weather.current.wind_kph,
+            .winddirDegree = weather.current.wind_dir,
+            .pressure = weather.current.pressure_mb,
+            .precipMM = weather.current.precip_mm,
+        },
+        .weather = blk: {
+            var forecast_array = std.ArrayList(struct {
+                date: []const u8,
+                maxtempC: f32,
+                mintempC: f32,
+                weatherCode: u16,
+                weatherDesc: []const u8,
+            }).init(allocator);
+            defer forecast_array.deinit();
 
-    return output.toOwnedSlice(allocator);
+            for (weather.forecast) |day| {
+                try forecast_array.append(.{
+                    .date = day.date,
+                    .maxtempC = day.max_temp_c,
+                    .mintempC = day.min_temp_c,
+                    .weatherCode = day.weather_code,
+                    .weatherDesc = day.condition,
+                });
+            }
+
+            break :blk try forecast_array.toOwnedSlice();
+        },
+    }, .{}, output.writer());
+
+    return output.toOwnedSlice();
+}
+
+test "render json format" {
+    const allocator = std.testing.allocator;
+
+    const weather = types.WeatherData{
+        .location = "London",
+        .current = .{
+            .temp_c = 15.0,
+            .temp_f = 59.0,
+            .condition = "Partly cloudy",
+            .weather_code = 116,
+            .humidity = 72,
+            .wind_kph = 13.0,
+            .wind_dir = "SW",
+            .pressure_mb = 1013.0,
+            .precip_mm = 0.0,
+        },
+        .forecast = &[_]types.ForecastDay{},
+        .allocator = allocator,
+    };
+
+    const output = try render(allocator, weather);
+    defer allocator.free(output);
+
+    try std.testing.expect(output.len > 0);
+    try std.testing.expect(std.mem.indexOf(u8, output, "temp_C") != null);
+    try std.testing.expect(std.mem.indexOf(u8, output, "15") != null);
 }

zig/src/weather/types.zig

@@ -1,5 +1,11 @@
 const std = @import("std");
 
+pub const WeatherError = error{
+    LocationNotFound,
+    ApiError,
+    NetworkError,
+};
+
 pub const WeatherData = struct {
     location: []const u8,
     current: CurrentCondition,