package geoip

import (
	"net/http"
	"testing"

	"github.com/carlosframework/platform/internal/geo"
)

func TestFromSnapshotStates(t *testing.T) {
	if a := FromSnapshot(geo.Snapshot{}); a.State != StateOff {
		t.Fatalf("not loaded = %+v, want off", a)
	}
	if a := FromSnapshot(geo.Snapshot{Loaded: true, Source: "DBIP-City-Lite"}); a.State != StateMiss || a.Source != "DBIP-City-Lite" {
		t.Fatalf("loaded miss = %+v", a)
	}
	hit := FromSnapshot(geo.Snapshot{Loaded: true, Found: true, Source: "GeoLite2-City",
		Result: geo.Result{Country: "GB", Subdivision: "GB-ENG", Point: geo.Point{Lat: 51.5074, Lon: -0.1278}, HasPoint: true}})
	if hit.State != StateHit || hit.Lat != 51.51 || hit.Lon != -0.13 {
		t.Fatalf("hit = %+v (coordinates must be rounded to 2 places)", hit)
	}
}

func TestWriteAppHeaders(t *testing.T) {
	h := http.Header{}
	h.Set(HeaderCountry, "XX") // stale value must go
	Answer{State: StateHit, Country: "IE", Source: "DBIP-City-Lite", Lat: 53.34, Lon: -6.27, HasPoint: true}.WriteApp(h)
	if h.Get(HeaderCountry) != "IE" || h.Get(HeaderLat) != "53.34" || h.Get(HeaderLon) != "-6.27" ||
		h.Get(HeaderSource) != "DBIP-City-Lite" || h.Get(HeaderSubdivision) != "" || h.Get(HeaderHop) != "" {
		t.Fatalf("headers = %v", h)
	}
	h2 := http.Header{}
	h2.Set(HeaderSource, "forged")
	Answer{State: StateMiss, Source: "DBIP-City-Lite"}.WriteApp(h2)
	if len(h2) != 0 {
		t.Fatalf("a miss sends no app headers, not even Source: %v", h2)
	}
}

func TestHopValueRoundTrip(t *testing.T) {
	for _, a := range []Answer{
		{State: StateHit, Country: "GB", Subdivision: "GB-ENG", Source: "GeoLite2-City", Lat: 51.51, Lon: -0.09, HasPoint: true},
		{State: StateHit, Source: "GeoLite2-City", Lat: 10, Lon: 20, HasPoint: true}, // coordinate-only (codex R3-3)
		{State: StateMiss, Source: "DBIP-City-Lite"},
		Off(),
	} {
		h := http.Header{}
		a.WriteApp(h)
		h.Set(HeaderHop, a.HopValue())
		got := Capture(h).Adopt()
		if got != a {
			t.Errorf("round trip %+v -> %+v", a, got)
		}
		if len(h) != 0 {
			t.Errorf("Capture must strip every geo header, left %v", h)
		}
	}
}

func TestAdoptRefusesWhatItCannotTrust(t *testing.T) {
	cases := map[string]http.Header{
		"no hop value":         {HeaderCountry: {"GB"}, HeaderSource: {"x"}},
		"malformed hop value":  {HeaderHop: {"maybe"}},
		"hit with nothing":     {HeaderHop: {"hit;src=x"}},
		"hit with bad country": {HeaderHop: {"hit;src=x"}, HeaderCountry: {"gb"}},
		"bad source":           {HeaderHop: {"hit;src=a b"}, HeaderCountry: {"GB"}},
	}
	for name, h := range cases {
		if got := Capture(h).Adopt(); got.State != StateOff {
			t.Errorf("%s: adopted %+v, want off", name, got)
		}
	}
	// Field-level: an invalid subdivision or half a coordinate pair is
	// dropped on its own, the rest survives.
	h := http.Header{HeaderHop: {"hit;src=GeoLite2-City"}, HeaderCountry: {"GB"},
		HeaderSubdivision: {"FR-IDF"}, HeaderLat: {"91"}, HeaderLon: {"0"}}
	got := Capture(h).Adopt()
	if got.State != StateHit || got.Country != "GB" || got.Subdivision != "" || got.HasPoint {
		t.Fatalf("partial = %+v", got)
	}
}

// Plan review R1-1: the whole reserved namespace goes, not just today's names.
func TestStripAllRemovesTheWholeNamespace(t *testing.T) {
	h := http.Header{}
	h.Set("X-Carlos-Geo-City", "Atlantis")
	h.Set("X-Carlos-Geo-Country", "KP")
	h["x-carlos-geo-asn"] = []string{"1"} // non-canonical key, as a hand-built map might hold
	h.Set(HeaderHop, "hit;src=x")
	h.Set("X-Carlos-Version", "keep me")
	h.Set("X-Geo-Country", "keep me too")
	StripAll(h)
	if len(h) != 2 || h.Get("X-Carlos-Version") == "" || h.Get("X-Geo-Country") == "" {
		t.Fatalf("after strip = %v", h)
	}
	h2 := http.Header{}
	h2.Set("X-Carlos-Geo-City", "Atlantis")
	Capture(h2)
	if len(h2) != 0 {
		t.Fatalf("Capture must strip the namespace too: %v", h2)
	}
}

// Code review R12-1: underscore spellings are the same header to CGI/WSGI.
func TestStripAllCatchesUnderscoreSpellings(t *testing.T) {
	h := http.Header{}
	for _, k := range []string{"X_Carlos_Geo_Country", "X_CARLOS_GEO_SOURCE", "X-Carlos_Geo-Lat", "X_Carlos_Hop_Geo", "x_carlos_hop_geo"} {
		h[k] = []string{"forged"}
	}
	h.Set("X-Carlos-Version", "keep")
	h["X_Forwarded_For"] = []string{"keep"}
	StripAll(h)
	if len(h) != 2 {
		t.Fatalf("after strip = %v", h)
	}
}