var system = require('system');
var fs = require('fs');

if (system.args.length !== 2) {
    console.log('Not enough args: [config_infile]');
    phantom.exit();
}

var resource_log = {};

var infile = system.args[1];
var config = JSON.parse(fs.read(infile));

var url = config.url;
var imgfile = config.imgfile;  // PhantomJS won't actually take the screenshot unless the destination file ends in ".png"
var htmlfile = config.htmlfile;

cookies = config["cookies"];
for(var cookie_index in cookies) {
    var could_store = phantom.addCookie(cookies[cookie_index]);
}

console.log("");
console.log("Screenshotting " + url + " to " + imgfile);
var page = require('webpage').create();
// Route "console.log()" calls from within the Page context to the main Phantom context (i.e. current "this")

// Log JavaScript console messages from the page to the command line
page.onConsoleMessage = function(msg) {
    console.log(msg);
};

// Store the HTTP status code for the requested page
page.onResourceReceived = function(res) {
    if(typeof page.httpstatus == "undefined") {  // PhantomJS calls this callback for every resource on the page. First resource is the page itself.
        //console.log(JSON.stringify(res, null, 4));
        page.httpstatus = res.status;
    }
};

function dump_html(page, htmlfile) {
    // TODO: Add logic here to validate that the size of the HTML the screenshot script captures is sane and not abusable
    fs.write(htmlfile, page.content);
}

function render_page(page, imgfile) {
    console.log("Page HTTP status: " + page.httpstatus);
    var could_screenshot = page.render(imgfile);
    console.log("Imgfile: " + imgfile);
    console.log("Could screenshot:" + could_screenshot);
    if(could_screenshot === true) {
        console.log("Screenshotted!");
    }

    return could_screenshot;
}

function log_resource_requested(request) {
    //console.log("request started: " + request.id);
    resource_log[request.id] = true;
}

function log_resource_received(response) {
    //console.log("response started: " + response.id);
    delete resource_log[response.id];
}

function screenshot_page(force_go) {
    if(Object.keys(resource_log).length !== 0) {
        //console.log("Waiting for resources to finish...");
        return setTimeout(function() {
            screenshot_page();
        }, 50);
    }

    if(force_go !== true) {  // All resources finished loading. Give page 400s more to load any more before we screenshot it.
        //console.log("Giving page one last chance to lead resources...");
        return setTimeout(function() {
            screenshot_page(true);
        }, 400);
    }

    //console.log("Screenshotting page");
    dump_html(page, htmlfile);
    var could_screenshot = render_page(page, imgfile);
    if(!could_screenshot) {
        phantom.exit(2);
        return;
    }

    phantom.exit(0);
}

page.viewportSize = {width: 960, height: 768};
page.onResourceRequested = log_resource_requested;
page.onResourceReceived = log_resource_received;

page.open(url, function(status) {
    console.log("Page opened: " + status);
    if(status != "success") {
        phantom.exit(1);
        return; // phantom.exit(n) doesn't reliably return that code if it's not the last call to exit() in the script. So. Stupid.
    }

    setTimeout(screenshot_page, 150);
});