package rigctld

import (
	"bufio"
	"fmt"
	"net"
	"strings"
	"sync"
	"testing"
)

// fakeRig stands in for the CAT manager.
type fakeRig struct {
	mu       sync.Mutex
	freq     int64
	mode     string
	split    bool
	txFreq   int64
	ptt      bool
	setFreqs []int64
	setModes []string
	failSet  bool
}

func (f *fakeRig) Freq() int64          { f.mu.Lock(); defer f.mu.Unlock(); return f.freq }
func (f *fakeRig) Mode() string         { f.mu.Lock(); defer f.mu.Unlock(); return f.mode }
func (f *fakeRig) Split() (bool, int64) { f.mu.Lock(); defer f.mu.Unlock(); return f.split, f.txFreq }
func (f *fakeRig) SetFreq(hz int64) error {
	f.mu.Lock()
	defer f.mu.Unlock()
	if f.failSet {
		return fmt.Errorf("rig refused")
	}
	f.freq = hz
	f.setFreqs = append(f.setFreqs, hz)
	return nil
}
func (f *fakeRig) SetMode(m string) error {
	f.mu.Lock()
	defer f.mu.Unlock()
	if f.failSet {
		return fmt.Errorf("rig refused")
	}
	f.mode = m
	f.setModes = append(f.setModes, m)
	return nil
}
func (f *fakeRig) SetPTT(on bool) error {
	f.mu.Lock()
	defer f.mu.Unlock()
	if f.failSet {
		return fmt.Errorf("rig refused")
	}
	f.ptt = on
	return nil
}

// The command table. These exact strings are what WSJT-X and MSHV put on the
// wire, so they are the contract — a reply in the wrong shape does not degrade
// gracefully, the client simply refuses to work with the rig.
func TestHandleCommands(t *testing.T) {
	rig := &fakeRig{freq: 14074000, mode: "FT8", split: true, txFreq: 14100000}
	s := New(0, rig, nil)

	cases := []struct{ in, want string }{
		{"f", "14074000\n"},
		{"\\get_freq", "14074000\n"},
		{"m", "PKTUSB\n3000\n"}, // a digital mode reads as PKTUSB
		{"t", "0\n"},            // PTT always reads RX — see the comment
		{"v", "VFOA\n"},
		{"s", "1\nVFOB\n"},  // split on, TX on B
		{"i", "14100000\n"}, // split TX frequency
		{"F 14200000", "RPRT 0\n"},
		{"F 14200000.000000", "RPRT 0\n"}, // the float form clients also send
		{"M USB 2400", "RPRT 0\n"},
		{"T 1", "RPRT 0\n"},
		{"V VFOB", "RPRT 0\n"}, // accepted and ignored, never an error
		{"S 1 VFOB", "RPRT 0\n"},
		{"\\chk_vfo", "CHKVFO 0\n"},
		{"F", "RPRT -1\n"}, // missing argument
		{"F not_a_number", "RPRT -1\n"},
		{"Z", "RPRT -11\n"}, // unknown → answered, never silence
		{"", ""},
	}
	for _, c := range cases {
		got, _ := s.handle(c.in)
		if got != c.want {
			t.Errorf("handle(%q) = %q, want %q", c.in, got, c.want)
		}
	}
	if q := func() bool { _, q := s.handle("q"); return q }(); !q {
		t.Error("q must end the session")
	}
}

// A rig that refuses must produce an error report, not a success — a client told
// "RPRT 0" believes the radio moved and will log the wrong frequency.
func TestHandleReportsBackendFailure(t *testing.T) {
	s := New(0, &fakeRig{failSet: true}, nil)
	for _, in := range []string{"F 14200000", "M USB 2400", "T 1"} {
		if got, _ := s.handle(in); got != "RPRT -9\n" {
			t.Errorf("handle(%q) with a failing rig = %q, want RPRT -9", in, got)
		}
	}
}

// dump_state is parsed POSITIONALLY by Hamlib clients: WSJT-X reads the first
// line as the protocol version and refuses to continue if the block is short or
// misshapen. Pinning its shape is what stops a well-meaning edit from silently
// breaking every client.
func TestDumpStateShape(t *testing.T) {
	lines := strings.Split(strings.TrimRight(dumpState, "\n"), "\n")
	if len(lines) < 20 {
		t.Fatalf("dump_state has %d lines — clients expect the full capability block", len(lines))
	}
	if lines[0] != "0" {
		t.Errorf("dump_state protocol version = %q, want \"0\"", lines[0])
	}
	// The frequency-range lines must carry seven fields, or the client's parse
	// slides and every later capability is read from the wrong place.
	for _, i := range []int{3, 5} {
		if n := len(strings.Fields(lines[i])); n != 7 {
			t.Errorf("dump_state line %d has %d fields, want 7: %q", i, n, lines[i])
		}
	}
}

// End to end over a real socket, because the framing (one reply per line,
// flushed immediately) is as much a part of the contract as the text.
func TestServerOverTCP(t *testing.T) {
	rig := &fakeRig{freq: 7074000, mode: "SSB"}
	s := New(0, rig, nil)
	ln, err := net.Listen("tcp", "127.0.0.1:0")
	if err != nil {
		t.Fatalf("listen: %v", err)
	}
	s.mu.Lock()
	s.ln = ln
	s.mu.Unlock()
	go func() {
		for {
			c, err := ln.Accept()
			if err != nil {
				return
			}
			go s.serve(c)
		}
	}()
	defer s.Stop()

	c, err := net.DialTimeout("tcp", ln.Addr().String(), dialTimeout)
	if err != nil {
		t.Fatalf("dial: %v", err)
	}
	defer c.Close()
	r := bufio.NewReader(c)

	if _, err := c.Write([]byte("f\n")); err != nil {
		t.Fatalf("write: %v", err)
	}
	line, err := r.ReadString('\n')
	if err != nil {
		t.Fatalf("read: %v", err)
	}
	if strings.TrimSpace(line) != "7074000" {
		t.Errorf("get_freq over TCP = %q, want 7074000", strings.TrimSpace(line))
	}

	if _, err := c.Write([]byte("F 14074000\n")); err != nil {
		t.Fatalf("write: %v", err)
	}
	line, _ = r.ReadString('\n')
	if strings.TrimSpace(line) != "RPRT 0" {
		t.Errorf("set_freq over TCP = %q, want RPRT 0", strings.TrimSpace(line))
	}
	if got := rig.Freq(); got != 14074000 {
		t.Errorf("rig frequency = %d, want 14074000 — the command never reached it", got)
	}
}

func TestModeMapping(t *testing.T) {
	for _, c := range []struct{ adif, hamlib string }{
		{"SSB", "USB"}, {"LSB", "LSB"}, {"CW", "CW"}, {"RTTY", "RTTY"},
		{"FT8", "PKTUSB"}, {"JS8", "PKTUSB"}, {"", "USB"},
	} {
		if got := adifToHamlib(c.adif); got != c.hamlib {
			t.Errorf("adifToHamlib(%q) = %q, want %q", c.adif, got, c.hamlib)
		}
	}
	// Digital comes back as DATA, never as a specific sub-mode: the CAT backend
	// applies the operator's own digital default, so a client that switches the
	// rig to data does not relabel a JS8 operator's QSOs as FT8.
	for _, c := range []struct{ hamlib, adif string }{
		{"PKTUSB", "DATA"}, {"PKTLSB", "DATA"}, {"DIGU", "DATA"},
		{"USB", "USB"}, {"CWR", "CW"}, {"FMN", "FM"},
	} {
		if got := hamlibToADIF(c.hamlib); got != c.adif {
			t.Errorf("hamlibToADIF(%q) = %q, want %q", c.hamlib, got, c.adif)
		}
	}
}