import ts=require("typescript");
import tsm=require("./tsASTMatchers");
import path=require("path");
import fs=require("fs");

import tsStructureParser=require("./tsStructureParser");
import {HelperMethod} from "./helpers";
import {Meta} from "./helpers";
import {Arg} from "./helpers";

export function getHelperMethods(srcPath:string):HelperMethod[]{

    var result:HelperMethod[] = [];
    var content = fs.readFileSync(path.resolve(srcPath)).toString();

    var mod = ts.createSourceFile("sample.ts",content,ts.ScriptTarget.ES3,true);

    tsm.Matching.visit(mod,x=>{

        var node = <any>x;
        if(node.kind==ts.SyntaxKind.FunctionDeclaration){

            var meta = getMeta(node,content);
            if(!meta){
                return;
            }
            var originalName = node.name.text;
            var wrapperMethodName = originalName;
            if(meta.name){
                wrapperMethodName = meta.name;
            }
            else{
                meta.name = originalName;
            }
            var wrapperMethodName = meta.name ? meta.name : originalName;
            var args = node.parameters ? node.parameters.map(a=>readArg(a,srcPath)) : [];
            var override = meta.override ? meta.override : false;
            var returnType = tsStructureParser.buildType(node.type, srcPath);
            result.push( new HelperMethod(originalName,wrapperMethodName, returnType,args,meta) );
        }
    });
    return result;
}

var refineComment = function (comment) {
    return comment.replace(/^\s*\/\*+/g,'').replace(/\*+\/\s*$/g,'').split('\n')
        .map(x=>x.replace(/^\s*\/\//g, '').replace(/^\s*\* {0,1}/g,'')).join('\n').trim();
};
function getMeta(node,content:string):Meta{

    var cRange:any = ts.getLeadingCommentRanges(content,node.pos);
    if(!cRange){
        return null;
    }

    var comment = cRange.map(x=>content.substring(x.pos,x.end)).join('\n');

    var ind = comment.indexOf('__$helperMethod__');
    if(ind<0){
        return null;
    }
    ind += '__$helperMethod__'.length;

    var indMeta = comment.indexOf('__$meta__');
    if(indMeta<0){
        return { comment: refineComment(comment.substring(ind)) };
    }

    var commentStr = refineComment(comment.substring(ind,indMeta));

    var indMetaObj = comment.indexOf('{',indMeta);
    if(indMetaObj<0){
        return { comment: commentStr};
    }

    try{
        var meta = JSON.parse(refineComment(comment.substring(indMetaObj)));
        meta.comment = commentStr.trim().length >0 ? commentStr : null;
        meta.override = meta.override || false
        meta.primary = meta.primary || false
        meta.deprecated = meta.deprecated || false;
        return meta;
    }
    catch(e){
        console.log(e);
    }

    return {};
}

function readArg(node,srcPath:string):Arg{

    var name = node.name.text;

    var type = tsStructureParser.buildType(node.type,srcPath);
    
    var defaultValue;    
    var optional = node.questionToken != null;
    if(node.initializer != null){
        defaultValue = tsStructureParser.parseArg(node.initializer);
        optional = true;
    }
    return {
        name:name,
        type:type,
        defaultValue: defaultValue,
        optional: optional
    }


}