package main

import (
	"context"
	"errors"
	"strings"
	"testing"
	"time"

	tea "github.com/charmbracelet/bubbletea"
	"github.com/charmbracelet/x/ansi"
)

type healthTestService struct {
	components []HealthComponent
	rate       RateLimitSnapshot
}

func (s *healthTestService) ListPullRequests(
	context.Context, string, string, int, bool,
) ([]PullRequest, error) {
	return nil, nil
}

func (s *healthTestService) GetPullRequest(
	context.Context, string, string, int,
) (PRDetails, error) {
	return PRDetails{}, nil
}

func (s *healthTestService) HealthReport() []HealthComponent {
	return append([]HealthComponent(nil), s.components...)
}

func (s *healthTestService) RateLimit() RateLimitSnapshot { return s.rate }

func TestHealthScreenReportsComponentsRateLimitAndEvents(t *testing.T) {
	service := &healthTestService{
		components: []HealthComponent{{
			Name: "GitHub API", Level: healthOK, Summary: "request succeeded",
		}},
		rate: RateLimitSnapshot{
			Limit: 5000, Remaining: 42, UpdatedAt: time.Now(),
			ResetAt: time.Now().Add(time.Hour),
		},
	}
	settings := defaultAppSettings()
	settings.ReadState = loadReadState(t.TempDir() + "/state.json")
	settings.Drafts = loadDraftStore(t.TempDir() + "/drafts.json")
	app := NewAppWithSettings(service, "o", "r", false, 50, time.Minute, settings)
	app.width, app.height = 64, 30
	app.details = PRDetails{
		PullRequest: PullRequest{ID: "pr", UpdatedAt: time.Now()},
		DataIssues:  []DataIssue{{Component: "timeline", Message: "unavailable"}},
	}
	app.recordHealth("timeline", healthWarning, "a deliberately long warning that must remain readable")

	lines := app.healthLines()
	plain := ansi.Strip(strings.Join(lines, "\n"))
	for _, wanted := range []string{
		"configuration", "read state", "draft persistence", "GitHub API",
		"rate limit", "42/5000", "PR core data", "timeline",
	} {
		if !strings.Contains(plain, wanted) {
			t.Fatalf("health output missing %q:\n%s", wanted, plain)
		}
	}
	for _, line := range lines {
		if ansi.StringWidth(line) > app.width-2 {
			t.Fatalf("health line width = %d, want <= %d: %q", ansi.StringWidth(line), app.width-2, line)
		}
	}
}

func TestHealthScreenOpensAndReturnsToPreviousScreen(t *testing.T) {
	app := NewApp(nil, "", "", false, 50, time.Minute)
	app.screen = dashboardScreen
	app.scroll = 7
	app.width, app.height = 100, 30

	updated, _ := app.Update(runeKey("H"))
	app = updated.(App)
	if app.screen != healthScreen || app.healthReturn != dashboardScreen || app.scroll != 7 {
		t.Fatalf("health navigation = screen %v return %v", app.screen, app.healthReturn)
	}
	view := ansi.Strip(app.View())
	if !strings.Contains(view, "Application health") ||
		!strings.Contains(view, "╭") || !strings.Contains(view, "╰") {
		t.Fatalf("health is not rendered as a modal:\n%s", view)
	}
	updated, _ = app.Update(tea.KeyMsg{Type: tea.KeyEsc})
	app = updated.(App)
	if app.screen != dashboardScreen || app.scroll != 7 {
		t.Fatalf("health back returned to screen %v at scroll %d", app.screen, app.scroll)
	}
}

func TestHealthRefreshLineIsStableAndInformational(t *testing.T) {
	app := NewApp(nil, "", "", false, 50, time.Minute)
	app.width, app.height = 100, 30
	app.loading = false
	idle := app.healthLines()
	app.loading = true
	loading := app.healthLines()

	findRefresh := func(lines []string) (int, string) {
		for index, line := range lines {
			plain := ansi.Strip(line)
			if strings.Contains(plain, "refresh") {
				return index, plain
			}
		}
		return -1, ""
	}
	idleIndex, idleLine := findRefresh(idle)
	loadingIndex, loadingLine := findRefresh(loading)
	if idleIndex < 0 || idleIndex != loadingIndex {
		t.Fatalf("refresh line moved from %d to %d", idleIndex, loadingIndex)
	}
	if !strings.Contains(idleLine, "OK") || !strings.Contains(loadingLine, "INFO") ||
		strings.Contains(loadingLine, "WARN") {
		t.Fatalf("refresh states: idle=%q loading=%q", idleLine, loadingLine)
	}
}

func TestAdaptivePollingHonorsRateLimitBackoff(t *testing.T) {
	now := time.Unix(1000, 0)
	service := &healthTestService{rate: RateLimitSnapshot{
		Limit: 5000, Remaining: 100, UpdatedAt: now,
	}}
	app := NewApp(service, "", "", false, 50, 10*time.Second)
	got := app.adaptivePollInterval(now)
	if got < 72*time.Second || got > 88*time.Second {
		t.Fatalf("low-budget interval = %s, want about 80s with jitter", got)
	}

	service.rate.RetryAfter = now.Add(2 * time.Minute)
	got = app.adaptivePollInterval(now)
	if got < 108*time.Second || got > 132*time.Second {
		t.Fatalf("retry-after interval = %s, want about 2m with jitter", got)
	}
}

func TestRequestCoordinatorCancelsSupersededRequest(t *testing.T) {
	var coordinator requestCoordinator
	first, cancelFirst, firstID := coordinator.start(time.Minute)
	defer cancelFirst()
	_, cancelSecond, secondID := coordinator.start(time.Minute)
	defer cancelSecond()
	select {
	case <-first.Done():
	default:
		t.Fatal("superseded request context was not canceled")
	}
	if coordinator.current(firstID) || !coordinator.current(secondID) {
		t.Fatalf("current request ids: first=%t second=%t",
			coordinator.current(firstID), coordinator.current(secondID))
	}
	if !errors.Is(first.Err(), context.Canceled) {
		t.Fatalf("first context error = %v", first.Err())
	}
}

func TestPartialRefreshPreservesLastCompleteSubsections(t *testing.T) {
	previous := PRDetails{
		PullRequest:   PullRequest{Owner: "o", Repository: "r", Number: 1},
		HeadOID:       "head",
		BaseOID:       "base",
		Threads:       []ReviewThread{{ID: "old-thread"}, {ID: "second-thread"}},
		Conversation:  []PRComment{{ID: "old-comment"}, {ID: "second-comment"}},
		ConflictFiles: []string{"conflicted.go"},
		Checks: []Check{{
			ID: "check", Annotations: []CheckAnnotation{{Path: "problem.go"}},
		}},
	}
	fresh := PRDetails{
		PullRequest:  PullRequest{Owner: "o", Repository: "r", Number: 1},
		HeadOID:      "head",
		BaseOID:      "base",
		Threads:      []ReviewThread{{ID: "first-page-only"}},
		Conversation: []PRComment{{ID: "first-page-only"}},
		Checks:       []Check{{ID: "check"}},
		DataIssues: []DataIssue{
			{Component: "review threads", Message: "page failed"},
			{Component: "conversation", Message: "page failed"},
		},
	}
	merged := preservePartialPRData(fresh, previous)
	if len(merged.Threads) != 2 || merged.Threads[0].ID != "old-thread" {
		t.Fatalf("preserved threads = %#v", merged.Threads)
	}
	if len(merged.Conversation) != 2 || merged.Conversation[0].ID != "old-comment" {
		t.Fatalf("preserved conversation = %#v", merged.Conversation)
	}
	if len(merged.DataIssues) != 2 {
		t.Fatalf("partial markers were lost: %#v", merged.DataIssues)
	}
	if len(merged.ConflictFiles) != 1 || len(merged.Checks[0].Annotations) != 1 {
		t.Fatalf("secondary data flickered during core refresh: %#v", merged)
	}
}