package main

import (
	"net/http"
	"net/http/httptest"
	"os"
	"path/filepath"
	"strings"
	"testing"
)

// fakeModel answers with the given replies in order and keeps what it was asked.
type fakeModel struct {
	replies []string
	asked   [][]chatMessage
}

func (f *fakeModel) name() string { return "fake" }
func (f *fakeModel) chat(m []chatMessage, _ map[string]any) (string, error) {
	f.asked = append(f.asked, append([]chatMessage{}, m...))
	r := f.replies[0]
	f.replies = f.replies[1:]
	return r, nil
}

func TestDiagnoseRunsRequestedChecksBeforeAnswering(t *testing.T) {
	srv := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if strings.HasPrefix(r.URL.Path, "/search") {
			w.Write([]byte(`{"results":[{"url":"https://example.com/fix","title":"Server stops at start","content":"set a password"}]}`))
			return
		}
		w.Write([]byte("The server refuses to run without a join password."))
	}))
	defer srv.Close()
	games := t.TempDir()
	os.MkdirAll(filepath.Join(games, "example"), 0o755)
	os.WriteFile(filepath.Join(games, "example", "game.yaml"), []byte("id: example\nname: Example\n"), 0o644)

	m := &fakeModel{replies: []string{
		`{"cause":"unsure","evidence":"no error line","confidence":"low","fix":"","checks":[{"type":"search","query":"example server stops at start"}]}`,
		`{"cause":"the server needs a join password","evidence":"the search result says so","confidence":"high","fix":"give JoinPassword x-generate","checks":[]}`,
	}}
	iv := &investigator{m: m, gameName: "Example", gamesDir: games, id: "example", searx: srv.URL, reader: srv.URL}
	d, err := iv.diagnose("FAILED: server crashed and was restarted 1 time(s)\nError: could not start")
	if err != nil {
		t.Fatal(err)
	}
	if d.Confidence != "high" || !strings.Contains(d.Fix, "x-generate") {
		t.Errorf("diagnosis: %+v", d)
	}
	second := m.asked[1]
	last := second[len(second)-1].Content
	if !strings.Contains(last, "Results of your checks") || !strings.Contains(last, "https://example.com/fix") ||
		!strings.Contains(last, "refuses to run without a join password") {
		t.Errorf("check results not sent back:\n%s", last)
	}
	// The first question already carried the web evidence for the error line
	if first := m.asked[0][1].Content; !strings.Contains(first, "What the web says") {
		t.Errorf("no web evidence in:\n%s", first)
	}
}

func TestAttemptLogRulesOutCausesThatChangedNothing(t *testing.T) {
	iv := &investigator{}
	iv.record(&diagnosis{Cause: "Not enough memory.", Fix: "requiredMemoryMb 8192"})
	iv.outcome(false, "FAILED: server crashed", "FAILED: server crashed")
	if !strings.HasPrefix(iv.log[0].Outcome, "unchanged") {
		t.Errorf("outcome %q", iv.log[0].Outcome)
	}
	if !iv.ruledOut(&diagnosis{Cause: "not enough memory"}) {
		t.Error("the same cause again should be ruled out")
	}
	if iv.ruledOut(&diagnosis{Cause: "the join password is empty"}) {
		t.Error("a new cause is not ruled out")
	}
	if !strings.Contains(iv.logText(), "ruled its cause out") {
		t.Error("log text should tell the model")
	}
	iv.record(&diagnosis{Cause: "empty join password", Fix: "x-generate"})
	iv.outcome(true, "FAILED: server crashed", "")
	if !strings.HasPrefix(iv.log[1].Outcome, "fixed") || iv.ruledOut(&diagnosis{Cause: "empty join password"}) {
		t.Errorf("fixed cause: %+v", iv.log[1])
	}
}

func TestDistinctErrorsDropsTimestampsAndRepeats(t *testing.T) {
	out := "[boot-test] FAILED: container exited\n" +
		"10/26/2026 01:12:02: Error: failed to bind port 30000\n" +
		"10/26/2026 01:12:03: Error: failed to bind port 30001\n" +
		"all fine here\n" +
		"[12:00:01] Fatal: missing config file"
	got := distinctErrors(out, 5)
	if len(got) != 2 || got[0] != "Error: failed to bind port 30000" || got[1] != "Fatal: missing config file" {
		t.Errorf("got %q", got)
	}
}

func TestCopyTemplateWithAppliesTheChange(t *testing.T) {
	src, dst := filepath.Join(t.TempDir(), "example"), filepath.Join(t.TempDir(), "example")
	os.MkdirAll(src, 0o755)
	os.WriteFile(filepath.Join(src, "game.yaml"), []byte("id: example\nname: Example\ndefaultStartupCommand: ./server\ndefaultConfig:\n  JoinPassword: \"\"\n"), 0o644)
	os.WriteFile(filepath.Join(src, "test.yaml"), []byte("timeoutSec: 600\n"), 0o644)
	if err := copyTemplateWith(src, dst, checkRequest{Config: map[string]string{"JoinPassword": "secret1"}, Startup: "./server -verbose"}); err != nil {
		t.Fatal(err)
	}
	g, err := loadMap(filepath.Join(dst, "game.yaml"))
	if err != nil {
		t.Fatal(err)
	}
	if g["defaultStartupCommand"] != "./server -verbose" || g["defaultConfig"].(map[string]any)["JoinPassword"] != "secret1" {
		t.Errorf("got %v", g)
	}
	if _, err := os.Stat(filepath.Join(dst, "test.yaml")); err != nil {
		t.Error("test.yaml not copied")
	}
	if got := describeChange(checkRequest{Config: map[string]string{"JoinPassword": "secret1"}}); got != `JoinPassword="secret1"` {
		t.Errorf("describe: %s", got)
	}
}

func TestFixRequestCarriesTheDiagnosis(t *testing.T) {
	got := strings.Join(fixRequest("FAILED: server crashed\nlog...", &diagnosis{Cause: "c", Evidence: "e", Fix: "f"}), "")
	for _, want := range []string{"FAILED: server crashed", "- cause: c", "- fix: f", "Apply exactly this fix"} {
		if !strings.Contains(got, want) {
			t.Errorf("missing %q in %s", want, got)
		}
	}
}