// NOTE: These fields aren't mandatory in the sense that snippet generation will fail
// if they're not set, but they're really, really, really expected to be there.
var _MANDATORY_PARAMS = {
    scenario: { "SCENARIO_NAME": "scenario name", "SCENARIO_DATE": "scenario date" },
} ;

var _MONTH_NAMES = [ // nb: we assume English :-/
    "January", "February", "March", "April", "May", "June",
    "July", "August", "September", "October", "November", "December"
] ;

// --------------------------------------------------------------------

function generate_snippet( $btn )
{
    // initialize
    storeMsgForTestSuite( "_last-info_", "" ) ;
    storeMsgForTestSuite( "_last-warning_", "" ) ;
    storeMsgForTestSuite( "_last-error_", "" ) ;

    // unload the template parameters
    var params = unload_params() ;
    var template_id = $btn.data( "id" ) ;
    if ( template_id === "ob_setup_1" ) {
        template_id = "ob_setup" ;
        params.OB_SETUP = params.OB_SETUP_1 ;
        params.OB_SETUP_COLOR = gNationalities[params.PLAYER_1].ob_colors[0] ;
        params.OB_SETUP_COLOR_2 = gNationalities[params.PLAYER_1].ob_colors[1] ;
        params.OB_SETUP_WIDTH = params.OB_SETUP_WIDTH_1 ;
    }
    else if ( template_id === "ob_setup_2" ) {
        template_id = "ob_setup" ;
        params.OB_SETUP = params.OB_SETUP_2 ;
        params.OB_SETUP_COLOR = gNationalities[params.PLAYER_2].ob_colors[0] ;
        params.OB_SETUP_COLOR_2 = gNationalities[params.PLAYER_2].ob_colors[1] ;
        params.OB_SETUP_WIDTH = params.OB_SETUP_WIDTH_2 ;
    }

    // extract the scenario date components
    var scenario_date = $("input[name='SCENARIO_DATE']").datepicker( "getDate" ) ;
    if ( scenario_date ) {
        params.SCENARIO_DAY_OF_MONTH = scenario_date.getDate() ;
        params.SCENARIO_MONTH = 1 + scenario_date.getMonth() ;
        params.SCENARIO_MONTH_NAME = _MONTH_NAMES[scenario_date.getMonth()] ;
        params.SCENARIO_YEAR = scenario_date.getFullYear() ;
    }

    // generate PF parameters
    if ( params.SCENARIO_YEAR < 1944 || (params.SCENARIO_YEAR == 1944 && params.SCENARIO_MONTH < 6) )
        params.PF_RANGE = 1 ;
    else if ( params.SCENARIO_YEAR == 1944 )
        params.PF_RANGE = 2 ;
    else
        params.PF_RANGE = 3 ;
    if ( params.SCENARIO_YEAR < 1943 || (params.SCENARIO_YEAR == 1943 && params.SCENARIO_MONTH <= 9) ) {
        params.PF_CHECK_DRM = "+1" ;
        params.PF_CHECK_DR = 4 ;
    } else if ( params.SCENARIO_YEAR >= 1945 ) {
        params.PF_CHECK_DRM = "-1" ;
        params.PF_CHECK_DR = 4 ;
    } else {
        params.PF_CHECK_DRM = "" ;
        params.PF_CHECK_DR = 3 ;
    }

    // generate BAZ parameters
    if ( params.SCENARIO_YEAR >= 1945 ) {
        params.BAZ_TYPE = 45 ;
        params.BAZ_BREAKDOWN = 11 ;
        params.BAZ_TOKILL = 16 ;
        params.BAZ_WP = 6 ;
        params.BAZ_RANGE = 5 ;
    } else if ( params.SCENARIO_YEAR >= 1944 ) {
        params.BAZ_TYPE = 44 ;
        params.BAZ_BREAKDOWN = 11 ;
        params.BAZ_TOKILL = 16 ;
        params.BAZ_RANGE = 4 ;
    } else if ( params.SCENARIO_YEAR == 1943 || (params.SCENARIO_YEAR == 1942 && params.SCENARIO_MONTH >= 11) ) {
        params.BAZ_TYPE = 43 ;
        params.BAZ_BREAKDOWN = 10 ;
        params.BAZ_TOKILL = 13 ;
        params.BAZ_RANGE = 4 ;
    }

    // check for mandatory parameters
    if ( template_id in _MANDATORY_PARAMS ) {
        var missing_params = [] ;
        for ( var param_id in _MANDATORY_PARAMS[template_id] ) {
            if ( ! (param_id in params && params[param_id].length > 0) )
                missing_params.push( _MANDATORY_PARAMS[template_id][param_id] ) ;
        }
        if ( missing_params.length > 0 ) {
            var buf = [ "Missing parameters:<ul>" ] ;
            for ( var i=0 ; i < missing_params.length ; ++i )
                buf.push( "<li>" + escapeHTML(missing_params[i]) ) ;
            buf.push( "</ul>" ) ;
            showWarningMsg( buf.join("") ) ;
        }
    }

    // check for date-specific parameters
    if ( template_id === "pf" ) {
        if ( params.SCENARIO_DATE === "" || params.SCENARIO_YEAR <= 1942 || (params.SCENARIO_YEAR == 1943 && params.SCENARIO_MONTH <= 9) )
            showWarningMsg( "PF are only available after September 1943." ) ;
    }
    if ( template_id === "baz" ) {
        if ( params.SCENARIO_DATE === "" || params.SCENARIO_YEAR <= 1941 || (params.SCENARIO_YEAR == 1942 && params.SCENARIO_MONTH < 11) )
        showWarningMsg( "BAZ are only available from November 1942." ) ;
    }

    // check that the players have different nationalities
    if ( params.PLAYER_1 === params.PLAYER_2 )
        showWarningMsg( "Both players have the same nationality!" ) ;

    // get the template to generate the snippet from
    var templ ;
    if ( template_id in gUserDefinedTemplates )
        templ = gUserDefinedTemplates[template_id] ;
    else if ( template_id in gDefaultTemplates )
        templ = gDefaultTemplates[template_id] ;
    else {
        showErrorMsg( "Unknown template: " + escapeHTML(template_id) ) ;
        return ;
    }
    var func, val ;
    try {
        func = jinja.compile( templ ).render ;
    }
    catch( ex ) {
        showErrorMsg( "Can't compile template:<pre>" + escapeHTML(ex) + "</pre>" ) ;
        return ;
    }

    // process the template
    try {
        val = func( params ) ;
        val = val.trim() ;
    }
    catch( ex ) {
        showErrorMsg( "Can't process template <em>\"" + template_id + "\"</em>:<pre>" + escapeHTML(ex) + "</pre>" ) ;
        return ;
    }
    try {
        copyToClipboard( val ) ;
    }
    catch( ex ) {
        showErrorMsg( "Can't copy to the clipboard:<pre>" + escapeHTML(ex) + "</pre>" ) ;
        return ;
    }
    showInfoMsg( "The HTML snippet has been copied to the clipboard." ) ;
}

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

function unload_params()
{
    // collect all the template parameters
    var params = {} ;
    add_param = function($elem) { params[ $elem.attr("name") ] = $elem.val() ; } ;
    $("input[type='text'].param").each( function() { add_param($(this)) ; } ) ;
    $("textarea.param").each( function() { add_param($(this)) ; } ) ;
    $("select.param").each( function() { add_param($(this)) ; } ) ;

    // collect the SSR's
    params.SSR = [] ;
    $("#ssr-sortable li").each( function() {
        params.SSR.push( $(this).text() ) ;
    } ) ;

    return params ;
}

// --------------------------------------------------------------------

function on_load_scenario()
{
    // FIXME! confirm this operation if the scenario is dirty

    // FOR TESTING PORPOISES! We can't control a file upload from Selenium (since
    // the browser will use native controls), so we store the result in a <div>).
    if ( getUrlParam( "scenario_persistence" ) ) {
        var $elem = $( "#scenario_persistence" ) ; // nb: must have already been created
        do_load_scenario( JSON.parse( $elem.val() ) ) ;
        return ;
    }

    // ask the user to upload the scenario file
    $("#load-scenario").trigger( "click" ) ;
}

function on_load_scenario_file_selected()
{
    // read the selected file
    var fileReader = new FileReader() ;
    fileReader.onload = function() {
        var data ;
        try {
            data = JSON.parse( fileReader.result ) ;
        } catch( ex ) {
            showErrorMsg( "Can't load the scenario file:<div>" + escapeHTML(ex) + "</div>" ) ;
            return ;
        }
        do_load_scenario( data ) ;
        showInfoMsg( "The scenario was loaded." ) ;
    } ;
    fileReader.readAsText( $("#load-scenario").prop("files")[0] ) ;
}

function do_load_scenario( params )
{
    // load the scenario parameters
    on_new_scenario( false ) ;
    var params_loaded = {} ;
    var set_param = function( $elem, key ) { $elem.val(params[key]) ; params_loaded[key]=true ; return $elem ; } ;
    for ( var key in params ) {
        if ( key === "SSR" ) {
            for ( var i=0 ; i < params[key].length ; ++i ) {
                var $ssr = $( "<li></li>" ) ;
                $ssr.text( params[key][i] ) ;
                $("#ssr-sortable").append( $ssr ) ;
                init_ssr( $ssr ) ;
            }
            update_ssr_hint() ;
            params_loaded[key] = true ;
            continue ;
        }
        //jshint loopfunc: true
        var $elem = $("input[type='text'][name='"+key+"'].param").each( function() {
            set_param( $(this), key ) ;
        } ) ;
        $elem = $("textarea[type='text'][name='"+key+"'].param").each( function() {
            set_param( $(this), key ) ;
        } ) ;
        $elem = $("select[name='"+key+"'].param").each( function() {
            set_param( $(this), key ).trigger( "change" ) ;
        } ) ;
    }

    // look for unrecognized keys
    var buf = [] ;
    for ( key in params ) {
        if ( ! (key in params_loaded) )
            buf.push( "<li>" + key + " = '" + escapeHTML(params[key]) + "'" ) ;
    }
    if ( buf.length > 0 )
        showWarningMsg( "Unknown keys in the scenario file:<ul>" + buf.join("") + "</ul>" ) ;
}

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

function on_save_scenario()
{
    // unload the template parameters
    var params = unload_params() ;
    var data = JSON.stringify( params ) ;

    // FOR TESTING PORPOISES! We can't control a file download from Selenium (since
    // the browser will use native controls), so we store the result in a <div>).
    if ( getUrlParam( "scenario_persistence" ) ) {
        var $elem = $( "#scenario_persistence" ) ;
        if ( $elem.length === 0 ) {
            // NOTE: The <div> we store the message in must be visible, otherwise
            // Selenium doesn't return any text for it :-/
            $elem = $( "<textarea id='scenario_persistence' style='z-index-999;'></textarea>" ) ;
            $("body").append( $elem ) ;
        }
        $elem.val( data ) ;
        return ;
    }

    // return the parameters to the user as a downloadable file
    download( data, "scenario.json", "application/json" ) ;
}

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

function on_new_scenario( verbose )
{
    // FIXME! confirm this operation if the scenario is dirty

    // reset all the template parameters
    $("input[type='text'].param").each( function() { $(this).val("") ; } ) ;
    $("textarea.param").each( function() { $(this).val("") ; } ) ;

    // reset all the template parameters
    on_player_change( $("select[name='PLAYER_1']").val( "german" ) ) ;
    $("select[name='PLAYER_1_ELR']").val( 5 ) ;
    $("select[name='PLAYER_1_SAN']").val( 2 ) ;
    on_player_change( $("select[name='PLAYER_2']").val( "russian" ) ) ;
    $("select[name='PLAYER_2_ELR']").val( 5 ) ;
    $("select[name='PLAYER_2_SAN']").val( 2 ) ;

    // reset all the template parameters
    $("#ssr-sortable li").each( function() {
        $(this).remove() ;
    } ) ;
    update_ssr_hint() ;
    if ( verbose )
        showInfoMsg( "The scenario was reset." ) ;
}

// --------------------------------------------------------------------

function on_template_pack()
{
    // FOR TESTING PORPOISES! We can't control a file upload from Selenium (since
    // the browser will use native controls), so we store the result in a <div>).
    if ( getUrlParam( "template_pack_persistence" ) ) {
        var data = $( "#template_pack_persistence" ).val() ; // nb: must have already been created
        var pos = data.indexOf( "|" ) ;
        var fname = data.substring( 0, pos ).trim() ;
        data = data.substring( pos+1 ).trim() ;
        if ( fname.substring(fname.length-4) == ".zip" )
            data = atob( data ) ;
        do_load_template_pack( fname, data ) ;
        return ;
    }

    // ask the user to upload the template pack
    $("#load-template-pack").trigger( "click" ) ;
}

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

function on_template_pack_file_selected()
{
    // read the selected file
    var MAX_FILE_SIZE = 2 ; // nb: MB
    var file = $("#load-template-pack").prop("files")[0] ;
    if ( file.size > 1024*1024*MAX_FILE_SIZE ) {
        showErrorMsg( "Template pack is too large (must be no larger than " + MAX_FILE_SIZE + "MB)." ) ;
        return ;
    }
    var fileReader = new FileReader() ;
    fileReader.onload = function() {
        var data = fileReader.result ;
        do_load_template_pack( file.name, data ) ;
    } ;
    fileReader.readAsArrayBuffer( file ) ;
}

// - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - -

function do_load_template_pack( fname, data )
{
    // initialize
    var invalid_filename_extns = [] ;
    var unknown_template_ids = [] ;
    var new_templates = {} ;

    // initialize
    function on_new_template( fname, data ) {
        // make sure the filename is valid
        if ( fname.substring(fname.length-3) != ".j2" ) {
            invalid_filename_extns.push( fname ) ;
            return ;
        }
        var template_id = fname.substring( 0, fname.length-3 ).toLowerCase() ;
        if ( ! (template_id in gDefaultTemplates) ) {
            unknown_template_ids.push( fname ) ;
            return ;
        }
        // save the new template file
        new_templates[template_id] = data ;
    }

    // initialize
    function install_new_templates( success_msg ) {
        // check if there were any errors
        var ok = true ;
        var buf, tid, i ;
        if ( invalid_filename_extns.length > 0 ) {
            buf = [] ;
            buf.push(
                "Invalid template ",
                pluralString( invalid_filename_extns.length, "extension:", "extensions:" ),
                "<div class='pre'>"
            ) ;
            for ( i=0 ; i < invalid_filename_extns.length ; ++i )
                buf.push( escapeHTML(invalid_filename_extns[i]) + "<br>" ) ;
            buf.push( "</div>" ) ;
            buf.push( 'Must be <span class="pre">".zip"</span> or <span class="pre">".j2"</span>.' ) ;
            showErrorMsg( buf.join("") ) ;
            ok = false ;
        }
        if ( unknown_template_ids.length > 0 ) {
            buf = [] ;
            buf.push(
                "Invalid template ",
                pluralString( unknown_template_ids.length, "filename:", "filenames:" ),
                "<div class='pre'>"
            ) ;
            for ( i=0 ; i < unknown_template_ids.length ; ++i )
                buf.push( escapeHTML(unknown_template_ids[i]) + "<br>" ) ;
            buf.push( "</div>" ) ;
            buf.push( "Must be one of:<div class='pre'><ul>" ) ;
            for ( tid in gDefaultTemplates )
                buf.push( "<li>" + escapeHTML(tid) + ".j2" ) ;
            buf.push( "</ul></div>" ) ;
            showErrorMsg( buf.join("") ) ;
            ok = false ;
        }
        if ( ! ok )
            return ;
        // all good - install the new templates
        for ( tid in new_templates ){
            gUserDefinedTemplates[tid] = new_templates[tid] ;
        }
        showInfoMsg( success_msg ) ;
    }

    // check if we have a ZIP file
    fname = fname.toLowerCase() ;
    if ( fname.substring(fname.length-4) == ".zip" ) {
        // yup - process each file in the ZIP
        var nFiles = 0 ;
        JSZip.loadAsync( data ).then( function( zip ) {
            zip.forEach( function( relPath, zipEntry ) {
                ++ nFiles ;
                zipEntry.async( "string" ).then( function( data ) {
                    // extract the filename (i.e. we ignore sub-directories)
                    fname = zipEntry.name ;
                    var pos = Math.max( fname.lastIndexOf("/"), fname.lastIndexOf("\\") ) ;
                    if ( pos === fname.length-1 )
                        return ; // nb: ignore directory entries
                    if ( pos !== -1 )
                        fname = fname.substring( pos+1 ) ;
                    on_new_template( fname, data ) ;
                } ).then( function() {
                    if ( --nFiles === 0 ) {
                        install_new_templates( "The template pack was loaded." ) ;
                    }
                } ) ;
            } ) ;
        } ).catch( function(ex) {
            showErrorMsg( "Can't unpack the ZIP:<div class='pre'>" + escapeHTML(ex) + "</div>" ) ;
        } ) ;
    }
    else {
        // nope - assume an individual template file
        on_new_template( fname, data ) ;
        install_new_templates( "The template file was loaded." ) ;
    }

}