/* -*- Mode: Java; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- /
/* vim: set shiftwidth=2 tabstop=2 autoindent cindent expandtab: */

/*
 * A Test Driver for PDF.js
 */

'use strict';

var appPath, browser, canvas, currentTaskIdx, manifest, stdout;

function queryParams() {
    var qs = window.location.search.substring(1);
    var kvs = qs.split("&");
    var params = { };
    for (var i = 0; i < kvs.length; ++i) {
        var kv = kvs[i].split("=");
        params[unescape(kv[0])] = unescape(kv[1]);
    }
    return params;
}

function load() {
    var params = queryParams();
    browser = params.browser;
    var manifestFile = params.manifestFile;
    appPath = params.path;

    canvas = document.createElement("canvas");
    canvas.mozOpaque = true;
    stdout = document.getElementById("stdout");

    log("load...\n");

    log("Harness thinks this browser is '"+ browser + "' with path " + appPath + "\n");
    log("Fetching manifest "+ manifestFile +"...");

    var r = new XMLHttpRequest();
    r.open("GET", manifestFile, false);
    r.onreadystatechange = function(e) {
        if (r.readyState == 4) {
            log("done\n");
            manifest = JSON.parse(r.responseText);
            currentTaskIdx = 0, nextTask();
        }
    };
    r.send(null);
}
window.onload = load;

function nextTask() {
    if (currentTaskIdx == manifest.length) {
        return done();
    }
    var task = manifest[currentTaskIdx];
    task.round = 0;

    log("Loading file "+ task.file +"\n");

    var r = new XMLHttpRequest();
    r.open("GET", task.file);
    r.mozResponseType = r.responseType = "arraybuffer";
    r.onreadystatechange = function() {
        var failure;
        if (r.readyState == 4) {
            var data = r.mozResponseArrayBuffer || r.mozResponse ||
                r.responseArrayBuffer || r.response;

            try {
                task.pdfDoc = new PDFDoc(new Stream(data));
            } catch(e) {
                failure = 'load PDF doc: '+ e.toString();
            }

            task.pageNum = 1, nextPage(task, failure);
        }
    };
    r.send(null);
}

function isLastPage(task) {
    return (!task.pdfDoc || (task.pageNum > task.pdfDoc.numPages));
}

function nextPage(task, loadError) {
    if (isLastPage(task)) {
	      if (++task.round < task.rounds) {
	          log("  Round "+ (1 + task.round) +"\n");
	          task.pageNum = 1;
	      } else {
	          ++currentTaskIdx, nextTask();
	          return;
        }
    }

    var failure = loadError || '';

    var ctx = null;
    var page = null;
    if (!failure) {
        try {
            log("    loading page "+ task.pageNum +"/"+ task.pdfDoc.numPages +"... ");
            ctx = canvas.getContext("2d");
            page = task.pdfDoc.getPage(task.pageNum);

            var pdfToCssUnitsCoef = 96.0 / 72.0;
            // using mediaBox for the canvas size
            var pageWidth = page.width;
            var pageHeight = page.height;
            canvas.width = pageWidth * pdfToCssUnitsCoef;
            canvas.height = pageHeight * pdfToCssUnitsCoef;
            clear(ctx);

            page.startRendering(
              ctx,
              function(e) {
                snapshotCurrentPage(page, task,
                                    (!failure && e) ? ('render: '+ e) : failure);
              });
        } catch(e) {
            failure = 'page setup: '+ e.toString();
        }
    }

    if (failure) {
        // Skip right to snapshotting if there was a failure, since the
        // fonts might be in an inconsistent state.
        snapshotCurrentPage(page, task, failure);
    }
}

function snapshotCurrentPage(page, task, failure) {
    log("done, snapshotting... ");

    sendTaskResult(canvas.toDataURL("image/png"), task, failure);
    log("done"+ (failure ? " (failed!: "+ failure +")" : "") +"\n");

    // Set up the next request
    var backoff = (inFlightRequests > 0) ? inFlightRequests * 10 : 0;
    setTimeout(function() {
        ++task.pageNum, nextPage(task);
    },
    backoff
  );
}

function sendQuitRequest() {
  var r = new XMLHttpRequest();
  r.open("POST", "/tellMeToQuit?path=" + escape(appPath), false);
  r.send("");
}

function quitApp() {
  log("Done!");
  document.body.innerHTML = "Tests are finished.  <h1>CLOSE ME!</h1>";
  if (window.SpecialPowers) {
    SpecialPowers.quitApplication();
  } else {
    sendQuitRequest();
    window.close();
  }
}

function done() {
  if (inFlightRequests > 0) {
    document.getElementById("inFlightCount").innerHTML = inFlightRequests;
    setTimeout(done, 100);
  } else {
    setTimeout(quitApp, 100);
  }
}

var inFlightRequests = 0;
function sendTaskResult(snapshot, task, failure) {
  var result = { browser: browser,
                 id: task.id,
                 numPages: task.pdfDoc.numPages,
                 failure: failure,
                 file: task.file,
                 round: task.round,
                 page: task.pageNum,
                 snapshot: snapshot };

  var r = new XMLHttpRequest();
  // (The POST URI is ignored atm.)
  r.open("POST", "/submit_task_results", true);
  r.setRequestHeader("Content-Type", "application/json");
  r.onreadystatechange = function(e) {
    if (r.readyState == 4) {
      inFlightRequests--;
    }
  }
  document.getElementById("inFlightCount").innerHTML = inFlightRequests++;
  r.send(JSON.stringify(result));
}

function clear(ctx) {
  ctx.save();
  ctx.fillStyle = "rgb(255, 255, 255)";
  ctx.fillRect(0, 0, canvas.width, canvas.height);
  ctx.restore();
}

/* Auto-scroll if the scrollbar is near the bottom, otherwise do nothing. */
function checkScrolling() {
  if ((stdout.scrollHeight - stdout.scrollTop) <= stdout.offsetHeight) {
    stdout.scrollTop = stdout.scrollHeight;
  }
}

function log(str) {
  stdout.innerHTML += str;
  checkScrolling();
}
