template.js

LyBBS基于Struts1.3/Ajax的架构

/**
 * TrimPath Template. Release 1.0.38.
 * Copyright (C) 2004, 2005 Metaha.
 * 
 * TrimPath Template is licensed under the GNU General Public License
 * and the Apache License, Version 2.0, as follows:
 *
 * This program is free software; you can redistribute it and/or 
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * 
 * This program is distributed WITHOUT ANY WARRANTY; without even the 
 * implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  
 * See the GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
var TrimPath;

// TODO: Debugging mode vs stop-on-error mode - runtime flag.
// TODO: Handle || (or) characters and backslashes.
// TODO: Add more modifiers.

(function() {               // Using a closure to keep global namespace clean.
    if (TrimPath == null)
        TrimPath = new Object();
    if (TrimPath.evalEx == null)
        TrimPath.evalEx = function(src) { return eval(src); };

    var UNDEFINED;
    if (Array.prototype.pop == null)  // IE 5.x fix from Igor Poteryaev.
        Array.prototype.pop = function() {
            if (this.length === 0) {return UNDEFINED;}
            return this[--this.length];
        };
    if (Array.prototype.push == null) // IE 5.x fix from Igor Poteryaev.
        Array.prototype.push = function() {
            for (var i = 0; i < arguments.length; ++i) {this[this.length] = arguments[i];}
            return this.length;
        };

    TrimPath.parseTemplate = function(tmplContent, optTmplName, optEtc) {
        if (optEtc == null)
            optEtc = TrimPath.parseTemplate_etc;
        var funcSrc = parse(tmplContent, optTmplName, optEtc);
        var func = TrimPath.evalEx(funcSrc, optTmplName, 1);
        if (func != null)
            return new optEtc.Template(optTmplName, tmplContent, funcSrc, func, optEtc);
        return null;
    }
    
    try {
        String.prototype.process = function(context, optFlags) {
            var template = TrimPath.parseTemplate(this, null);
            if (template != null)
                return template.process(context, optFlags);
            return this;
        }
    } catch (e) { // Swallow exception, such as when String.prototype is sealed.
    }
    
    TrimPath.parseTemplate_etc = {};            // Exposed for extensibility.
    TrimPath.parseTemplate_etc.statementTag = "forelse|for|if|elseif|else|var|macro";
    TrimPath.parseTemplate_etc.statementDef = { // Lookup table for statement tags.
        "if"     : { delta:  1, prefix: "if (", suffix: ") {", paramMin: 1 },
        "else"   : { delta:  0, prefix: "} else {" },
        "elseif" : { delta:  0, prefix: "} else if (", suffix: ") {", paramDefault: "true" },
        "/if"    : { delta: -1, prefix: "}" },
        "for"    : { delta:  1, paramMin: 3, 
                     prefixFunc : function(stmtParts, state, tmplName, etc) {
                        if (stmtParts[2] != "in")
                            throw new etc.ParseError(tmplName, state.line, "bad for loop statement: " + stmtParts.join(' '));
                        var iterVar = stmtParts[1];
                        var listVar = "__LIST__" + iterVar;
                        return [ "var ", listVar, " = ", stmtParts[3], ";",
                             // Fix from Ross Shaull for hash looping, make sure that we have an array of loop lengths to treat like a stack.
                             "var __LENGTH_STACK__;",
                             "if (typeof(__LENGTH_STACK__) == 'undefined' || !__LENGTH_STACK__.length) __LENGTH_STACK__ = new Array();", 
                             "__LENGTH_STACK__[__LENGTH_STACK__.length] = 0;", // Push a new for-loop onto the stack of loop lengths.
                             "if ((", listVar, ") != null) { ",
                             "var ", iterVar, "_ct = 0;",       // iterVar_ct variable, added by B. Bittman     
                             "for (var ", iterVar, "_index in ", listVar, ") { ",
                             iterVar, "_ct++;",
                             "if (typeof(", listVar, "[", iterVar, "_index]) == 'function') {continue;}", // IE 5.x fix from Igor Poteryaev.
                             "__LENGTH_STACK__[__LENGTH_STACK__.length - 1]++;",
                             "var ", iterVar, " = ", listVar, "[", iterVar, "_index];" ].join("");
                     } },
        "forelse" : { delta:  0, prefix: "} } if (__LENGTH_STACK__[__LENGTH_STACK__.length - 1] == 0) { if (", suffix: ") {", paramDefault: "true" },
        "/for"    : { delta: -1, prefix: "} }; delete __LENGTH_STACK__[__LENGTH_STACK__.length - 1];" }, // Remove the just-finished for-loop from the stack of loop lengths.
        "var"     : { delta:  0, prefix: "var ", suffix: ";" },
        "macro"   : { delta:  1, 
                      prefixFunc : function(stmtParts, state, tmplName, etc) {
                          var macroName = stmtParts[1].split('(')[0];
                          return [ "var ", macroName, " = function", 
                                   stmtParts.slice(1).join(' ').substring(macroName.length),
                                   "{ var _OUT_arr = []; var _OUT = { write: function(m) { if (m) _OUT_arr.push(m); } }; " ].join('');
                     } }, 
        "/macro"  : { delta: -1, prefix: " return _OUT_arr.join(''); };" }
    }
    TrimPath.parseTemplate_etc.modifierDef = {
        "eat"        : function(v)    { return ""; },
        "escape"     : function(s)    { return String(s).replace(/&/g, "&amp;").replace(/</g, "&lt;").replace(/>/g, "&gt;"); },
        "capitalize" : function(s)    { return String(s).toUpperCase(); },
        "default"    : function(s, d) { return s != null ? s : d; }
    }
    TrimPath.parseTemplate_etc.modifierDef.h = TrimPath.parseTemplate_etc.modifierDef.escape;

    TrimPath.parseTemplate_etc.Template = function(tmplName, tmplContent, funcSrc, func, etc) {
        this.process = function(context, flags) {
            if (context == null)
                context = {};
            if (context._MODIFIERS == null)
                context._MODIFIERS = {};
            if (context.defined == null)
                context.defined = function(str) { return (context[str] != undefined); };
            for (var k in etc.modifierDef) {
                if (context._MODIFIERS[k] == null)
                    context._MODIFIERS[k] = etc.modifierDef[k];
            }
            if (flags == null)
                flags = {};
            var resultArr = [];
            var resultOut = { write: function(m) { resultArr.push(m); } };
            try {
                func(resultOut, context, flags);
            } catch (e) {
                if (flags.throwExceptions == true)
                    throw e;
                var result = new String(resultArr.join("") + "[ERROR: " + e.toString() + (e.message ? '; ' + e.message : '') + "]");
                result["exception"] = e;
                return result;
            }
            return resultArr.join("");
        }
        this.name       = tmplName;
        this.source     = tmplContent; 
        this.sourceFunc = funcSrc;
        this.toString   = function() { return "TrimPath.Template [" + tmplName + "]"; }
    }
    TrimPath.parseTemplate_etc.ParseError = function(name, line, message) {
        this.name    = name;
        this.line    = line;
        this.message = message;
    }
    TrimPath.parseTemplate_etc.ParseError.prototype.toString = function() { 
        return ("TrimPath template ParseError in " + this.name + ": line " + this.line + ", " + this.message);
    }
    
    var parse = function(body, tmplName, etc) {
        body = cleanWhiteSpace(body);
        var funcText = [ "var TrimPath_Template_TEMP = function(_OUT, _CONTEXT, _FLAGS) { with (_CONTEXT) {" ];
        var state    = { stack: [], line: 1 };                              // TODO: Fix line number counting.
        var endStmtPrev = -1;
        while (endStmtPrev + 1 < body.length) {
            var begStmt = endStmtPrev;
            // Scan until we find some statement markup.
            begStmt = body.indexOf("{", begStmt + 1);
            while (begStmt >= 0) {
                var endStmt = body.indexOf('}', begStmt + 1);
                var stmt = body.substring(begStmt, endStmt);
                var blockrx = stmt.match(/^\{(cdata|minify|eval)/); // From B. Bittman, minify/eval/cdata implementation.
                if (blockrx) {
                    var blockType = blockrx[1]; 
                    var blockMarkerBeg = begStmt + blockType.length + 1;
                    var blockMarkerEnd = body.indexOf('}', blockMarkerBeg);
                    if (blockMarkerEnd >= 0) {
                        var blockMarker;
                        if( blockMarkerEnd - blockMarkerBeg <= 0 ) {
                            blockMarker = "{/" + blockType + "}";
                        } else {
                            blockMarker = body.substring(blockMarkerBeg + 1, blockMarkerEnd);
                        }                        
                        
                        var blockEnd = body.indexOf(blockMarker, blockMarkerEnd + 1);
                        if (blockEnd >= 0) {                            
                            emitSectionText(body.substring(endStmtPrev + 1, begStmt), funcText);
                            
                            var blockText = body.substring(blockMarkerEnd + 1, blockEnd);
                            if (blockType == 'cdata') {
                                emitText(blockText, funcText);
                            } else if (blockType == 'minify') {
                                emitText(scrubWhiteSpace(blockText), funcText);
                            } else if (blockType == 'eval') {
                                if (blockText != null && blockText.length > 0) // From B. Bittman, eval should not execute until process().