package bot

import (
	"context"
	"errors"
	"strings"
	"sync"
	"testing"

	"bellhop/internal/arr"

	"maunium.net/go/mautrix/id"
)

type stubClient struct {
	results []arr.Result
	addErr  error
	srchErr error

	searched string
	added    []arr.Result
}

func (s *stubClient) Search(_ context.Context, term string) ([]arr.Result, error) {
	s.searched = term
	if s.srchErr != nil {
		return nil, s.srchErr
	}
	return s.results, nil
}

func (s *stubClient) Add(_ context.Context, r arr.Result) error {
	if s.addErr != nil {
		return s.addErr
	}
	s.added = append(s.added, r)
	return nil
}

type stubReplier struct {
	mu       sync.Mutex
	plain    string
	htmlBody string
	calls    int
}

func (r *stubReplier) PostThreadedReply(_ context.Context, _ id.RoomID, _ id.EventID, plain, htmlBody string) error {
	r.mu.Lock()
	defer r.mu.Unlock()
	r.calls++
	r.plain = plain
	r.htmlBody = htmlBody
	return nil
}

func newDispatcher(prefix string, services Services, replier Replier) *Dispatcher {
	return New(context.Background(), prefix, services, replier)
}

const (
	room   = id.RoomID("!room:example.org")
	event  = id.EventID("$evt")
	sender = id.UserID("@alice:example.org")
)

func TestParseCommand(t *testing.T) {
	cases := []struct {
		body            string
		wantCmd, wantQ  string
		wantOk          bool
	}{
		{"!movie dune", "movie", "dune", true},
		{"  !movie  dune part two  ", "movie", "dune part two", true},
		{"!HELP", "help", "", true},
		{"hello world", "", "", false},
		{"!", "", "", false},
		{"!  ", "", "", false},
	}
	for _, c := range cases {
		cmd, q, ok := parseCommand("!", c.body)
		if cmd != c.wantCmd || q != c.wantQ || ok != c.wantOk {
			t.Errorf("parseCommand(%q) = (%q,%q,%v); want (%q,%q,%v)",
				c.body, cmd, q, ok, c.wantCmd, c.wantQ, c.wantOk)
		}
	}
}

func TestDispatchMovieTopHit(t *testing.T) {
	radarr := &stubClient{results: []arr.Result{
		{Title: "Dune", Year: 2021},
		{Title: "Dune", Year: 1984},
	}}
	rep := &stubReplier{}
	d := newDispatcher("!", Services{Radarr: radarr}, rep)

	d.Handle(room, event, sender, "!movie dune")

	if radarr.searched != "dune" {
		t.Fatalf("search term = %q", radarr.searched)
	}
	if len(radarr.added) != 1 || radarr.added[0].Year != 2021 {
		t.Fatalf("expected top hit added, got %+v", radarr.added)
	}
	if !strings.Contains(rep.plain, "Dune (2021)") || !strings.Contains(rep.plain, "Radarr") {
		t.Fatalf("reply missing expected content: %q", rep.plain)
	}
}

func TestDispatchNoResults(t *testing.T) {
	sonarr := &stubClient{}
	rep := &stubReplier{}
	d := newDispatcher("!", Services{Sonarr: sonarr}, rep)

	d.Handle(room, event, sender, "!tv obscure show")

	if len(sonarr.added) != 0 {
		t.Fatal("should not add when no results")
	}
	if !strings.Contains(rep.plain, "No Sonarr results") {
		t.Fatalf("unexpected reply: %q", rep.plain)
	}
}

func TestDispatchUnconfigured(t *testing.T) {
	rep := &stubReplier{}
	d := newDispatcher("!", Services{}, rep)

	d.Handle(room, event, sender, "!music radiohead")

	if !strings.Contains(rep.plain, "Lidarr is not configured") {
		t.Fatalf("unexpected reply: %q", rep.plain)
	}
}

func TestDispatchEmptyQuery(t *testing.T) {
	radarr := &stubClient{}
	rep := &stubReplier{}
	d := newDispatcher("!", Services{Radarr: radarr}, rep)

	d.Handle(room, event, sender, "!movie")

	if radarr.searched != "" {
		t.Fatal("should not search with empty query")
	}
	if !strings.Contains(rep.plain, "Usage:") {
		t.Fatalf("unexpected reply: %q", rep.plain)
	}
}

func TestDispatchAddError(t *testing.T) {
	radarr := &stubClient{
		results: []arr.Result{{Title: "Dune", Year: 2021}},
		addErr:  errors.New("boom"),
	}
	rep := &stubReplier{}
	d := newDispatcher("!", Services{Radarr: radarr}, rep)

	d.Handle(room, event, sender, "!movie dune")

	if !strings.Contains(rep.plain, "failed to add") || !strings.Contains(rep.plain, "boom") {
		t.Fatalf("unexpected reply: %q", rep.plain)
	}
}

func TestDispatchSearchError(t *testing.T) {
	radarr := &stubClient{srchErr: errors.New("network down")}
	rep := &stubReplier{}
	d := newDispatcher("!", Services{Radarr: radarr}, rep)

	d.Handle(room, event, sender, "!movie dune")

	if !strings.Contains(rep.plain, "search failed") {
		t.Fatalf("unexpected reply: %q", rep.plain)
	}
}

func TestDispatchHelp(t *testing.T) {
	rep := &stubReplier{}
	d := newDispatcher("!", Services{}, rep)

	d.Handle(room, event, sender, "!help")

	for _, want := range []string{"!movie", "!tv", "!music", "!help"} {
		if !strings.Contains(rep.plain, want) {
			t.Errorf("help missing %q: %q", want, rep.plain)
		}
	}
}

func TestDispatchUnknown(t *testing.T) {
	rep := &stubReplier{}
	d := newDispatcher("!", Services{}, rep)

	d.Handle(room, event, sender, "!frobnicate stuff")

	if !strings.Contains(rep.plain, "Unknown command") {
		t.Fatalf("unexpected reply: %q", rep.plain)
	}
}

func TestNonCommandIgnored(t *testing.T) {
	rep := &stubReplier{}
	d := newDispatcher("!", Services{}, rep)

	d.Handle(room, event, sender, "just chatting")

	if rep.calls != 0 {
		t.Fatalf("expected no reply, got %d", rep.calls)
	}
}

func TestDispatchAlreadyInLibrary(t *testing.T) {
	radarr := &stubClient{results: []arr.Result{{Title: "Dune", Year: 2021, Exists: true}}}
	rep := &stubReplier{}
	d := newDispatcher("!", Services{Radarr: radarr}, rep)

	d.Handle(room, event, sender, "!movie dune")

	if len(radarr.added) != 0 {
		t.Fatalf("should not re-add existing item, got %d adds", len(radarr.added))
	}
	if !strings.Contains(rep.plain, "already has") || !strings.Contains(rep.plain, "Dune (2021)") {
		t.Fatalf("unexpected reply: %q", rep.plain)
	}
}

func TestCustomPrefix(t *testing.T) {
	radarr := &stubClient{results: []arr.Result{{Title: "Dune", Year: 2021}}}
	rep := &stubReplier{}
	d := newDispatcher(".bh ", Services{Radarr: radarr}, rep)

	d.Handle(room, event, sender, ".bh movie dune")

	if len(radarr.added) != 1 {
		t.Fatalf("expected add, got %d", len(radarr.added))
	}
}