
/*
 * weinre is available under *either* the terms of the modified BSD license *or* the
 * MIT License (2008). See http://opensource.org/licenses/alphabetical for full text.
 * 
 * Copyright (c) 2010, 2011 IBM Corporation
 */

requireClass ../common/Binding

//-----------------------------------------------------------------------------
class SqlStepper(steps)
    if (!(this instanceof SqlStepper)) return new SqlStepper(steps)
    
    this.__context = {}
    
    var context = this.__context
    context.steps = steps
    
//-----------------------------------------------------------------------------
method run(db, errorCallback)
    var context = this.__context
    
    if (context.hasBeenRun) 
        throw new Ex(arguments, "stepper has already been run")
        
    context.hasBeenRun = true
        
    context.db            = db
    context.errorCallback = errorCallback
    context.nextStep      = 0
    
    context.ourErrorCallback = new Binding(this, ourErrorCallback)
    context.runStep          = new Binding(this, runStep)
    this.executeSql          = new Binding(this, executeSql)
    
    db.transaction(context.runStep)
    
//-----------------------------------------------------------------------------
function executeSql(statement, data)
    var context = this.__context
    
    context.tx.executeSql(statement, data, context.runStep, context.ourErrorCallback)

//-----------------------------------------------------------------------------
function ourErrorCallback(tx, sqlError)
    var context = this.__context
    
    context.errorCallback.call(this, sqlError)
    
//-----------------------------------------------------------------------------
function runStep(tx, resultSet)
    var context = this.__context
    
    if (context.nextStep >= context.steps.length) return
    
    context.tx = tx
    
    context.currentStep = context.nextStep
    context.nextStep++
    
    var step = context.steps[context.currentStep]
    
    step.call(this, resultSet)

//-----------------------------------------------------------------------------
static method example(db, id)
    function step1() {
        this.executeSql("SELECT name FROM sqlite_master WHERE type='table'")
    }
    
    function step2(resultSet) {
        var rows = resultSet.rows
        var result = []
        for (var i=0; i<rows.length; i++) {
            var name = rows.item(i).name
            if (name == "__WebKitDatabaseInfoTable__") continue
        
            result.push(name)
        }
        
        console.log("[" + this.id + "] table names: " + result.join(", "))
    }

    function errorCb(sqlError) {
        
        console.log("[" + this.id + "] sql error:" + sqlError.code + ": " + sqlError.message)
    }
    
    var stepper = new SqlStepper([step1, step2])
    stepper.id = id
    stepper.run(db, errorCb)