package com.battery.device.bts;

import static org.junit.jupiter.api.Assertions.assertEquals;
import static org.junit.jupiter.api.Assertions.assertFalse;
import static org.junit.jupiter.api.Assertions.assertThrows;
import static org.junit.jupiter.api.Assertions.assertTrue;
import java.math.BigDecimal;
import java.time.Instant;
import java.time.ZoneId;
import java.util.List;
import java.util.Map;
import java.util.Set;
import org.junit.jupiter.api.Test;
import com.battery.device.api.model.ChannelIdentity;
import com.battery.device.api.model.DeviceWorkStatus;
import com.battery.device.api.model.RealtimeSnapshot;

class BtsXmlCodecTest
{
    private final BtsXmlCodec codec = new BtsXmlCodec("lab-bts", ZoneId.of("Asia/Hong_Kong"));

    @Test
    void parsesDeviceDiscoveryAndChannelIdentity()
    {
        String xml = "<bts version=\"1.0\"><cmd>getdevinfo_resp</cmd><middle count=\"1\">"
                + "<channel ip=\"192.168.1.35\" devtype=\"22\" devid=\"1\" subdevid=\"2\" Channelid=\"3\">true</channel>"
                + "</middle></bts>";

        var channels = codec.parseDeviceInfo(xml);

        assertEquals(1, channels.size());
        assertEquals(new ChannelIdentity("lab-bts", 22, 1, 2, 3), channels.get(0).identity());
        assertEquals("192.168.1.35", channels.get(0).serverIp());
    }

    @Test
    void rejectsInvalidDiscoveryAvailability()
    {
        String xml = "<bts><cmd>getdevinfo_resp</cmd><middle count=\"1\">"
                + "<channel ip=\"192.168.1.35\" devtype=\"22\" devid=\"1\" subdevid=\"2\" Channelid=\"3\">maybe</channel>"
                + "</middle></bts>";

        BtsProtocolException exception = assertThrows(BtsProtocolException.class,
                () -> codec.parseDeviceInfo(xml));

        assertEquals(BtsProtocolException.Reason.INVALID_VALUE, exception.reason());
    }

    @Test
    void parsesRealtimeCoreDynamicAndDbcMeasurements()
    {
        String xml = "<bts version=\"1.0\"><cmd>inquire_resp</cmd><list count=\"1\">"
                + "<inquire dev=\"22-3-2-7-0\" cycle_id=\"2\" step_id=\"4\" step_type=\"cc\" workstatus=\"working\" "
                + "current=\"1.2\" voltage=\"3.5\" capacity=\"0.1\" energy=\"0.35\" T1=\"23.4\" log_code=\"0\">"
                + "<DBC message_name=\"Frame1\" signal_name=\"Soc\" value=\"88.5\" unit=\"%\"/></inquire>"
                + "</list></bts>";

        Map<ChannelIdentity, RealtimeSnapshot> result = codec.parseSnapshots(xml, Instant.parse("2026-08-25T10:00:00Z"));
        RealtimeSnapshot snapshot = result.values().iterator().next();

        assertEquals(DeviceWorkStatus.WORKING, snapshot.workStatus());
        assertEquals(new BigDecimal("1.2"), snapshot.currentA());
        assertEquals(new BigDecimal("23.4"), snapshot.measurements().get("T1").value());
        assertEquals("%", snapshot.measurements().get("DBC:Frame1:Soc").unit());
    }

    @Test
    void mapsUnknownWorkStatusWithoutDiscardingSnapshot()
    {
        String xml = "<bts><cmd>inquire_resp</cmd><list count=\"1\"><inquire dev=\"22-1-1-1-0\" workstatus=\"futureState\"/></list></bts>";

        RealtimeSnapshot snapshot = codec.parseSnapshots(xml, Instant.EPOCH).values().iterator().next();

        assertEquals(DeviceWorkStatus.UNKNOWN, snapshot.workStatus());
    }

    @Test
    void mapsFinishAsNormalCompletion()
    {
        String xml = "<bts><cmd>inquire_resp</cmd><list count=\"1\">"
                + "<inquire dev=\"22-1-1-1-0\" workstatus=\"finish\"/></list></bts>";

        RealtimeSnapshot snapshot = codec.parseSnapshots(xml, Instant.EPOCH).values().iterator().next();

        assertEquals(DeviceWorkStatus.FINISHED, snapshot.workStatus());
    }




    @Test
    void rejectsIllegalNumericData()
    {
        String xml = "<bts><cmd>inquire_resp</cmd><list count=\"1\"><inquire dev=\"22-1-1-1-0\" current=\"bad\"/></list></bts>";

        BtsProtocolException exception = assertThrows(BtsProtocolException.class,
                () -> codec.parseSnapshots(xml, Instant.EPOCH));

        assertEquals(BtsProtocolException.Reason.INVALID_VALUE, exception.reason());
    }

    @Test
    void classifiesWrongCommandAndMalformedXml()
    {
        BtsProtocolException wrongCommand = assertThrows(BtsProtocolException.class,
                () -> codec.parseSnapshots("<bts><cmd>download_resp</cmd></bts>", Instant.EPOCH));
        BtsProtocolException malformed = assertThrows(BtsProtocolException.class,
                () -> codec.parseSnapshots("<bts><cmd>inquire_resp</cmd>", Instant.EPOCH));

        assertEquals(BtsProtocolException.Reason.UNEXPECTED_COMMAND, wrongCommand.reason());
        assertEquals(BtsProtocolException.Reason.MALFORMED_XML, malformed.reason());
    }

    @Test
    void reportsMissingRequiredField()
    {
        String xml = "<bts><cmd>inquire_resp</cmd><list count=\"1\"><inquire workstatus=\"working\"/></list></bts>";

        BtsProtocolException exception = assertThrows(BtsProtocolException.class,
                () -> codec.parseSnapshots(xml, Instant.EPOCH));

        assertEquals(BtsProtocolException.Reason.MISSING_FIELD, exception.reason());
    }

    @Test
    void rejectsResponsesMissingRequiredContainers()
    {
        BtsProtocolException discovery = assertThrows(BtsProtocolException.class,
                () -> codec.parseDeviceInfo("<bts><cmd>getdevinfo_resp</cmd></bts>"));
        BtsProtocolException realtime = assertThrows(BtsProtocolException.class,
                () -> codec.parseSnapshots("<bts><cmd>inquire_resp</cmd></bts>", Instant.EPOCH));
        assertEquals(BtsProtocolException.Reason.MISSING_FIELD, discovery.reason());
        assertEquals(BtsProtocolException.Reason.MISSING_FIELD, realtime.reason());
    }

    @Test
    void rejectsDoctypeAndExternalEntities()
    {
        String xml = "<!DOCTYPE bts [<!ENTITY xxe SYSTEM \"file:///etc/passwd\">]><bts><cmd>inquire_resp</cmd>&xxe;</bts>";

        BtsProtocolException exception = assertThrows(BtsProtocolException.class,
                () -> codec.parseSnapshots(xml, Instant.EPOCH));
        assertFalse(exception.getMessage().isBlank());
    }
}