3

function dispatch_value(index, value) {

     4

    console.log("dispatch_value("+index+value+")");

     5

};

     7

// Open WebSocket to relative "/ws" address

     8

var ws = new WebSocket(window.location.href.replace(/^http(s?:\/\/[^\/]*)\/.*$/, 'ws$1/ws'));

     9

ws.binaryType = 'arraybuffer';

    11

const dvgetters = {

    12

    INT: [DataView.prototype.getInt16, 2],

    13

    BOOL: [DataView.prototype.getInt8, 1]

    14

    /* TODO */

    15

};

    16

    17

// Register message reception handler 

    18

ws.onmessage = function (evt) {

    19

    20

    let data = evt.data;

    21

    let dv = new DataView(data);

    22

    let i = 0;

    23

    for(let hash_int of hmi_hash) {

    24

        if(hash_int != dv.getUint8(i)){

    25

            console.log("Recv non maching hash. Reload.");

    26

    27

            // 1003 is for "Unsupported Data"

    28

            ws.close(1003,"Hash doesn't match");

    29

    30

            // TODO : remove debug alert ?

    31

            alert("HMI will be reloaded.");

    32

    33

            // force reload ignoring cache

    34

            location.reload(true);

    35

        };

    36

        i++;

    39

    while(i < data.length){

    40

        let index = dv.getUint32(i);

    41

        i += 4;

    42

        let iectype = hmitree_types[index];

    43

        let [dvgetter, bytesize] = dvgetters[iectypes];

    44

        value = dvgetter.call(dv,i);

    45

        dispatch_value(index, value);

    46

        i += bytesize;

    47

    };

    48

};

    51

function send_blob(data) {

    52

    if(data.length > 0) {

    53

        ws.send(new Blob([

    54

            new Uint8Array(hmi_hash), 

    55

            data]));

    57

};

    58

    59

const typedarray_types = {

    60

    INT: Int16Array,

    61

    BOOL: Uint8Array

    62

    /* TODO */

    63

};

    64

    65

function send_reset() {

    66

    send_blob(new Uint8Array([1])); /* reset = 1 */

    67

};

    68

    69

// subscription state, as it should be in hmi server

    70

// hmitree indexed array of integers

    71

var subscriptions =  hmitree_types.map(_ignored => 0);

    72

    73

// subscription state as needed by widget now

    74

// hmitree indexed array of Sets of widgets objects

    75

var subscribers = hmitree_types.map(_ignored => new Set());

    76

    77

function update_subscriptions() {

    78

    let delta = [];

    79

    for(let index = 0; index < subscribers.length; index++){

    80

        let widgets = subscribers[index];

    81

    82

        // periods are in ms

    83

        let previous_period = subscriptions[index];

    84

    85

        let new_period;

    86

        if(widgets.size > 0) {

    87

            let maxfreq = 0;

    88

            for(let widget of widgets)

    89

                if(maxfreq < widgets.frequency)

    90

                    maxfreq = widgets.frequency;

    91

    92

            new_period = 1000/maxfreq;

    93

        } else {

    94

            new_period = 0;

    95

        }

    96

    97

        if(previous_period != new_period) {

    98

            subscriptions[index] = new_period;

    99

            delta.push([

   100

                new Uint8Array([2]), /* subscribe = 2 */

   101

                new Uint32Array([index]), 

   102

                new Uint16Array([new_period])]);

   103

        }

   104

   105

    }

   106

    send_blob(delta);

   107

};

   108

   109

function update_value(index, value) {

   110

    iectype = hmitree_types[index];

   111

    jstype = typedarray_types[iectypes];

   112

    send_blob([

   113

        new Uint8Array([0]),  /* setval = 0 */

   114

        new jstype([value])

   115

        ]);

   116

   117

};

   118

   119

var current_page;

   120

   121

function switch_page(page_name) {

   122

    let old_desc = page_desc[current_page];

   123

    let new_desc = page_desc[page_name];

   124

    /* TODO hide / show widgets */

   125

    /* TODO move viewport */

   126

   127

    /* remove subsribers of previous page if any */

   128

    if(old_desc) for(let widget of old_desc.widgets){

   129

        for(let index of widget.indexes){

   130

            subscribers[index].delete(widget);

   131

        }

   132

    }

   133

    /* add new subsribers if any */

   134

    if(new_desc) for(let widget of new_desc.widgets){

   135

        for(let index of widget.indexes){

   136

            subscribers[index].add(widget);

   137

        }

   138

    }

   139

   140

    current_page = page_name;

   141

   142

    update_subscriptions();

   143

};

   144

   145

   146

// Once connection established

   147

ws.onopen = function (evt) {

   148

    send_reset();

   149

    // show main page

   150

    switch_page(default_page);

   151

   152

};

   153