#! /usr/bin/env node

/**
Entrypoint for the task graph extension / decisions for gaia tests.
*/

var decorate = require('../lib/decorate_task');
var yaml = require('js-yaml');
var fs = require('fs');
var fsPath = require('path');
var taskcluster = require('taskcluster-client');
var util = require('util');
var template = require('json-templater-fix/object');

// Cache for task definitions...
var TASK_DEFINITIONS = {};
function loadTask(name, parameters) {
  if (!TASK_DEFINITIONS[name]) {
    var path = fsPath.resolve(__dirname + '/../tasks/' + name + '.yml');
    TASK_DEFINITIONS[name] = yaml.safeLoad(fs.readFileSync(path));
  }
  return decorate(TASK_DEFINITIONS[name], parameters);
}

function params() {
  return Array.prototype.slice.call(arguments).reduce(function(target, props) {
    for (var key in props) target[key] = props[key];
    return target;
  }, {});
}

// List of all the possible definitions...
var config = yaml.safeLoad(fs.readFileSync(__dirname + '/../tasks.yml'));

// Map of task ids to task names.
var taskIdMap = {};

// Final task graph definition place holder...
var graph = {
  tasks: []
};

// XXX: When extending the task graph the scopes and metadata fields are invalid
// according to the schema so for local testing we need the --full option so the
// task graph can be submitted.
if (process.argv[2] == '--full') {
  graph.scopes = [
    'docker-worker:cache:resources',

    util.format(
      'queue:define-task:%s/%s',
      config.params.provisionerId, config.params.workerType
    ),

    util.format(
      'queue:create-task:%s/%s',
      config.params.provisionerId, config.params.workerType
    ),
  ];

  graph.metadata = {
    source: process.env.GITHUB_HEAD_GIT + '/blob/tests/taskcluster/bin/graph',
    owner: 'jlal@mozilla.com', // TODO: Obviously change this...
    description: 'Generated task graph for gaia',
    name: 'Gaia'
  };
}

var nextYear = new Date(Date.now());
nextYear.setFullYear(nextYear.getFullYear() + 1);
nextYear = nextYear.toJSON();

var currentTaskId = process.env.TASK_ID;
var currentRunId = process.env.RUN_ID;

//////////////////////
// Boostrap the graph
//////////////////////
taskIdMap['bootstrap'] = taskcluster.slugid();
var packageUrl = 'https://queue.taskcluster.net/v1/task/' + currentTaskId +
                 '/runs/' + currentRunId + '/artifacts/public/package.json';
var bootstrapTask = loadTask('../bootstrap', params(config.params, {
  process: process,
  nextYear: nextYear,
  packageUrl: packageUrl,
  taskId: taskIdMap['bootstrap']
}));
bootstrapTask.taskId = taskIdMap['bootstrap'];
graph.tasks.push(bootstrapTask);

///////////////////////
// Add dependent tasks
///////////////////////

// Expand all tasks based on the `tasks.yml` file...
Object.keys(config.definitions).forEach(function(name) {
  var definition = config.definitions[name];

  // If we are not using chunks don't loop.
  if (!definition || !definition.chunks) {
    taskIdMap[name] = taskcluster.slugid();
    var task = loadTask(name, params(config.params, {
      // Useful for environment variables.
      process: process,
      // For dependencies.
      nextYear: nextYear
    }));
    task.taskId = taskIdMap[name];
    task.requires = [taskIdMap['bootstrap']];
    graph.tasks.push(task);
    return;
  }

  // Handle all chunking options...
  for (var chunk = 1; chunk <= definition.chunks; chunk++) {
    // In practice relying on chunks in the graph is probably a bad idea unless
    // doing it explicitly with some sort of specific logic but here for
    // consistency.
    var taskId = taskIdMap[name + '-' + chunk] = taskcluster.slugid();
    var task = loadTask(name, params(config.params, {
      // Allow process to be used in variables useful for process.env.
      process: process,
      nextYear: nextYear,

      // Chunk parameters
      chunk: chunk,
      totalChunks: definition.chunks
    }));
    task.requires = [taskIdMap['bootstrap']];
    graph.tasks.push(task);
  }
});

graph.tasks = graph.tasks.map(function(task) {
  return template(task, { tasks: taskIdMap });
});

// Output the entire task graph for extension....
process.stdout.write(JSON.stringify(graph, null, 2));