package server

import (
	"net/http"
	"net/http/httptest"
	"testing"

	"github.com/pingcap/agent-git-service/internal/tenant"
)

func testTenantBinding(id, baseURL string, aliases ...string) tenantDomainBinding {
	return tenantDomainBinding{
		Info: tenant.Info{
			ID:               tenant.ID(id),
			CanonicalBaseURL: baseURL,
		},
		Aliases: aliases,
	}
}

func TestTenantResolverIsStrictWithOneTenant(t *testing.T) {
	resolver, err := newTenantResolver([]tenantDomainBinding{
		testTenantBinding("clawmem", "https://git.clawmem.ai"),
	}, false)
	if err != nil {
		t.Fatalf("newTenantResolver: %v", err)
	}

	known := httptest.NewRequest(http.MethodGet, "http://internal/api/v3", nil)
	known.Host = "git.clawmem.ai"
	if got := resolver.resolve(known); !got.OK || got.Tenant.ID != "clawmem" || got.Source != "host" {
		t.Fatalf("known resolution = %#v", got)
	}

	unknown := httptest.NewRequest(http.MethodGet, "http://internal/api/v3", nil)
	unknown.Host = "internal"
	if got := resolver.resolve(unknown); got.OK || got.Reason != "unknown_host" {
		t.Fatalf("unknown resolution = %#v", got)
	}
}

func TestTenantResolverUsesAliasesWithoutChangingTenantIdentity(t *testing.T) {
	resolver, err := newTenantResolver([]tenantDomainBinding{
		testTenantBinding("engineering", "https://git.ags.ai", "https://code.ags.ai"),
	}, false)
	if err != nil {
		t.Fatalf("newTenantResolver: %v", err)
	}

	req := httptest.NewRequest(http.MethodGet, "http://internal/api/v3", nil)
	req.Host = "code.ags.ai"
	got := resolver.resolve(req)
	if !got.OK || got.Tenant.ID != "engineering" || got.Tenant.BaseURL() != "https://git.ags.ai" {
		t.Fatalf("alias resolution = %#v", got)
	}
}

func TestTenantResolverTreatsForwardedHostAsAuthoritative(t *testing.T) {
	resolver, err := newTenantResolver([]tenantDomainBinding{
		testTenantBinding("clawmem", "https://git.clawmem.ai"),
		testTenantBinding("engineering", "https://git.ags.ai"),
	}, true)
	if err != nil {
		t.Fatalf("newTenantResolver: %v", err)
	}

	req := httptest.NewRequest(http.MethodGet, "http://internal/api/v3", nil)
	req.Host = "git.clawmem.ai"
	req.Header.Set("X-Forwarded-Host", "unknown.example")
	if got := resolver.resolve(req); got.OK || got.Source != "x_forwarded_host" || got.Reason != "unknown_host" {
		t.Fatalf("unknown forwarded resolution = %#v", got)
	}

	req.Header.Set("X-Forwarded-Host", "git.ags.ai, git.clawmem.ai")
	if got := resolver.resolve(req); got.OK || got.Reason != "invalid_host" {
		t.Fatalf("ambiguous forwarded resolution = %#v", got)
	}

	req.Header.Del("X-Forwarded-Host")
	if got := resolver.resolve(req); got.OK || got.Source != "x_forwarded_host" || got.Reason != "invalid_host" {
		t.Fatalf("missing forwarded resolution = %#v", got)
	}

	req.Header.Add("X-Forwarded-Host", "git.ags.ai")
	req.Header.Add("X-Forwarded-Host", "git.clawmem.ai")
	if got := resolver.resolve(req); got.OK || got.Reason != "invalid_host" {
		t.Fatalf("duplicate forwarded resolution = %#v", got)
	}
}

func TestTenantResolverRejectsDuplicateOrMalformedBindings(t *testing.T) {
	if _, err := newTenantResolver([]tenantDomainBinding{
		testTenantBinding("clawmem", "https://git.clawmem.ai"),
		testTenantBinding("engineering", "https://git.clawmem.ai"),
	}, false); err == nil {
		t.Fatal("expected duplicate host error")
	}

	if _, err := newTenantResolver([]tenantDomainBinding{
		testTenantBinding("engineering", "https://git.ags.ai/path"),
	}, false); err == nil {
		t.Fatal("expected malformed origin error")
	}
}

func TestTenantHostKeysNormalizeDefaultPorts(t *testing.T) {
	for _, tc := range []struct {
		origin string
		want   string
	}{
		{origin: "https://git.ags.ai:443", want: "git.ags.ai"},
		{origin: "http://git.ags.ai:80", want: "git.ags.ai"},
	} {
		keys, err := tenantOriginHostKeys(tc.origin)
		if err != nil {
			t.Fatalf("tenantOriginHostKeys(%q): %v", tc.origin, err)
		}
		found := false
		for _, key := range keys {
			if key == tc.want {
				found = true
			}
		}
		if !found {
			t.Fatalf("tenantOriginHostKeys(%q) = %#v, want %q", tc.origin, keys, tc.want)
		}
	}
}