var fs = require('fs'), assert = require('assert'), vm = require('vm');
var cptable, sbcs;

var Buffer_from = function(){};

if(typeof Buffer !== 'undefined') {
  var nbfs = !Buffer.from;
  if(!nbfs) try { Buffer.from("foo", "utf8"); } catch(e) { nbfs = true; }
  Buffer_from = nbfs ? function(buf, enc) { return (enc) ? new Buffer(buf, enc) : new Buffer(buf); } : Buffer.from.bind(Buffer);
}

describe('source', function() {
  it('should load node', function() { cptable = require('./'); });
  it('should load sbcs', function() { sbcs = require('./sbcs'); });
  it('should load excel', function() { excel = require('./cpexcel'); });
  it('should process bits', function() {
    var files = fs.readdirSync('bits').filter(function(x){return x.substr(-3)==".js";});
    files.forEach(function(x) {
      vm.runInThisContext(fs.readFileSync('./bits/' + x));
    });
  });
});
describe('README', function() {
  var readme = function() {
    var unicode_cp10000_255 = cptable[10000].dec[255]; // ˇ
    assert.equal(unicode_cp10000_255, "ˇ");

    var cp10000_711 = cptable[10000].enc[String.fromCharCode(711)]; // 255
    assert.equal(cp10000_711, 255);

    var b1 = [0xbb,0xe3,0xd7,0xdc];
    var s1 = b1.map(function(x) { return String.fromCharCode(x); }).join("");
    var 汇总 = cptable.utils.decode(936, b1);
    var buf =  cptable.utils.encode(936,  汇总);
    assert.equal(汇总,"汇总");
    assert.equal(buf.length, 4);
    for(var i = 0; i != 4; ++i) assert.equal(b1[i], buf[i]);

    var b2 = [0xf0,0x9f,0x8d,0xa3];
    var sushi= cptable.utils.decode(65001, b2);
    var sbuf = cptable.utils.encode(65001, sushi);
    assert.equal(sushi,"🍣");
    assert.equal(sbuf.length, 4);
    for(var i = 0; i != 4; ++i) assert.equal(b2[i], sbuf[i]);

  };
  it('should be correct', function() {
    cptable.utils.cache.encache();
    readme();
    cptable.utils.cache.decache();
    readme();
  });
});
describe('consistency', function() {
  cptable = require('./');
  U = cptable.utils;
  var chk = function(cptable, cacheit) { return function(x) {
    it('should consistently process CP ' + x, function() {
      var cp = cptable[x], D = cp.dec, E = cp.enc;
      if(cacheit) cptable.utils.cache.encache();
      else cptable.utils.cache.decache();
      Object.keys(D).forEach(function(d) {
        if(E[D[d]] != d) {
          if(typeof E[D[d]] !== "undefined") return;
          if(D[d].charCodeAt(0) == 0xFFFD) return;
          if(D[E[D[d]]] === D[d]) return;
          throw new Error(x + " e.d[" + d + "] = " + E[D[d]] + "; d[" + d + "]=" + D[d] + "; d.e.d[" + d + "] = " + D[E[D[d]]]);
        }
      });
      Object.keys(E).forEach(function(e) {
        if(D[E[e]] != e) {
          throw new Error(x + " d.e[" + e + "] = " + D[E[e]] + "; e[" + e + "]=" + E[e] + "; e.d.e[" + e + "] = " + E[D[E[e]]]);
        }
      });
      var corpus = ["foobar"];
      corpus.forEach(function(w){
        assert.equal(U.decode(x,U.encode(x,w)),w);
      });
      cptable.utils.cache.encache();
    });
  }; };
  describe('cached', function() {
    Object.keys(cptable).filter(function(w) { return w == +w; }).forEach(chk(cptable, true));
  });
  describe('direct', function() {
    Object.keys(cptable).filter(function(w) { return w == +w; }).forEach(chk(cptable, false));
  });
});
describe('entry conditions', function() {
  it('should fail to load utils if cptable unavailable', function() {
    var sandbox = {};
    var ctx = vm.createContext(sandbox);
    assert.throws(function() {
      vm.runInContext(fs.readFileSync('cputils.js','utf8'),ctx);
    });
  });
  it('should load utils if cptable is available', function() {
    var sandbox = {};
    var ctx = vm.createContext(sandbox);
    vm.runInContext(fs.readFileSync('cpexcel.js','utf8'),ctx);
    vm.runInContext(fs.readFileSync('cputils.js','utf8'),ctx);
  });
  var chken = function(cp, i) {
    var c = function(cp, i, e) {
      var str = cptable.utils.encode(cp,i,e);
      var arr = cptable.utils.encode(cp,i.split(""),e);
      assert.deepEqual(str,arr);
      if(typeof Buffer === 'undefined') return;
      var buf = cptable.utils.encode(cp,Buffer_from(i),e);
      assert.deepEqual(str,buf);
    };
    cptable.utils.cache.encache();
    c(cp,i);
    c(cp,i,'buf');
    c(cp,i,'arr');
    c(cp,i,'str');
    cptable.utils.cache.decache();
    c(cp,i);
    c(cp,i,'buf');
    c(cp,i,'arr');
    c(cp,i,'str');
  };
  describe('encode', function() {
    it('CP  1252 : sbcs', function() { chken(1252,"foo•bþr"); });
    it('CP   708 : sbcs', function() { chken(708,"ت and ث smiley faces");});
    it('CP   936 : dbcs', function() { chken(936, "这是中文字符测试");});
  });
  var chkde = function(cp, i) {
    var c = function(cp, i) {
      var s;
      if(typeof Buffer !== 'undefined' && i instanceof Buffer) s = [].map.call(i, function(s){return String.fromCharCode(s); });
      else s=(i.map) ? i.map(function(s){return String.fromCharCode(s); }) : i;
      var str = cptable.utils.decode(cp,i);
      var arr = cptable.utils.decode(cp,s.join?s.join(""):s);
      assert.deepEqual(str,arr);
      if(typeof Buffer === 'undefined') return;
      var buf = cptable.utils.decode(cp,Buffer_from(i));
      assert.deepEqual(str,buf);
    };
    cptable.utils.cache.encache();
    c(cp,i);
    cptable.utils.cache.decache();
    c(cp,i);
  };
  describe('decode', function() {
    it('CP  1252 : sbcs', function() { chkde(1252,[0x66, 0x6f, 0x6f, 0x62, 0x61, 0x72]); }); /* "foobar" */
    if(typeof Buffer !== 'undefined') it('CP   708 : sbcs', function() { chkde(708, Buffer_from([0xca, 0x20, 0x61, 0x6e, 0x64, 0x20, 0xcb, 0x20, 0x73, 0x6d, 0x69, 0x6c, 0x65, 0x79, 0x20, 0x66, 0x61, 0x63, 0x65, 0x73])); }); /* ("ت and ث smiley faces") */
    it('CP   936 : dbcs', function() { chkde(936, [0xd5, 0xe2, 0xca, 0xc7, 0xd6, 0xd0, 0xce, 0xc4, 0xd7, 0xd6, 0xb7, 0xfb, 0xb2, 0xe2, 0xca, 0xd4]);}); /* "这是中文字符测试" */
  });
});
function testfile(f,cp,type,skip) {
  var d = fs.readFileSync(f);
  var x = fs.readFileSync(f, type);
  var a = x.split("");
  var chk = function(cp) {
    var y = cptable.utils.decode(cp, d);
    assert.equal(x,y);
    var z = cptable.utils.encode(cp, x);
    if(z.length != d.length) throw new Error(f + " " + JSON.stringify(z) + " != " + JSON.stringify(d) + " : " + z.length + " " + d.length);
    for(var i = 0; i != d.length; ++i) if(d[i] !== z[i]) throw new Error("" + i + " " + d[i] + "!=" + z[i]);
    if(skip) return;
    z = cptable.utils.encode(cp, a);
    if(z.length != d.length) throw new Error(f + " " + JSON.stringify(z) + " != " + JSON.stringify(d) + " : " + z.length + " " + d.length);
    for(var i = 0; i != d.length; ++i) if(d[i] !== z[i]) throw new Error("" + i + " " + d[i] + "!=" + z[i]);
    if(f.indexOf("cptable.js") == -1) {
      cptable.utils.encode(cp, d, 'str');
      cptable.utils.encode(cp, d, 'arr');
    }
  }
  cptable.utils.cache.encache();
  chk(cp);
  if(skip) return;
  cptable.utils.cache.decache();
  chk(cp);
  cptable.utils.cache.encache();
}
describe('node natives', function() {
  var node = [[65001, 'utf8',1], [1200, 'utf16le',1], [20127, 'ascii',0]];
  var unicodefiles = ['codepage.md','README.md','cptable.js'];
  var asciifiles = ['cputils.js'];
  node.forEach(function(w) {
    describe(w[1], function() {
      cptable = require('./');
      asciifiles.forEach(function(f) {
        it('should process ' + f, function() { testfile('./misc/'+f+'.'+w[1],w[0],w[1]); });
      });
      if(!w[2]) return;
      unicodefiles.forEach(function(f) {
        it('should process ' + f, function() { testfile('./misc/'+f+'.'+w[1],w[0],w[1]); });
      });
      if(w[1] === 'utf8') it('should process bits', function() {
        var files = fs.readdirSync('bits').filter(function(x){return x.substr(-3)==".js";});
        files.forEach(function(f) { testfile('./bits/' + f,w[0],w[1],true); });
      });
    });
  });
});
var m = cptable.utils.magic;
function cmp(x,z) {
  assert.equal(x.length, z.length);
  for(var i = 0; i != z.length; ++i) assert.equal(i+"/"+x.length+""+x[i], i+"/"+z.length+""+z[i]);
}
Object.keys(m).forEach(function(t){if(t != 16969) describe(m[t], function() {
  it("should process codepage.md." + m[t], fs.existsSync('./misc/codepage.md.' + m[t]) ?
    function() {
      var b = fs.readFileSync('./misc/codepage.md.utf8', "utf8");
      if(m[t] === "ascii") b = b.replace(/[\u0080-\uffff]*/g,"");
      var x = fs.readFileSync('./misc/codepage.md.' + m[t]);
      var y, z;
      cptable.utils.cache.encache();
      y = cptable.utils.decode(t, x);
      assert.equal(y,b);
      z = cptable.utils.encode(t, y);
      if(t != 65000) cmp(x,z);
      else { assert.equal(y, cptable.utils.decode(t, z)); }
      cptable.utils.cache.decache();
      y = cptable.utils.decode(t, x);
      assert.equal(y,b);
      z = cptable.utils.encode(t, y);
      if(t != 65000) cmp(x,z);
      else { assert.equal(y, cptable.utils.decode(t, z)); }
      cptable.utils.cache.encache();
      cptable.utils.encode(t, y, 'str');
      cptable.utils.encode(t, y, 'arr');
      cptable.utils.cache.decache();
      cptable.utils.encode(t, y, 'str');
      cptable.utils.encode(t, y, 'arr');
      cptable.utils.cache.encache();
    }
  : null);
  it("should process README.md." + m[t], fs.existsSync('./misc/README.md.' + m[t]) ?
    function() {
      var b = fs.readFileSync('./misc/README.md.utf8', "utf8");
      if(m[t] === "ascii") b = b.replace(/[\u0080-\uffff]*/g,"");
      var x = fs.readFileSync('./misc/README.md.' + m[t]);
      x = [].slice.call(x);
      cptable.utils.cache.encache();
      var y = cptable.utils.decode(t, x);
      assert.equal(y,b);
      cptable.utils.cache.decache();
      var y = cptable.utils.decode(t, x);
      assert.equal(y,b);
      cptable.utils.cache.encache();
    }
  : null);
});});
describe('failures', function() {
  it('should fail to find CP 6969', function() {
    assert.throws(function(){cptable[6969].dec});
    assert.throws(function(){cptable[6969].enc});
  });
  it('should fail using utils', function() {
    assert(!cptable.utils.hascp(6969));
    assert.throws(function(){return cptable.utils.encode(6969, "foobar"); });
    assert.throws(function(){return cptable.utils.decode(6969, [0x20]); });
  });
  it('should fail with black magic', function() {
    assert(cptable.utils.hascp(16969));
    assert.throws(function(){return cptable.utils.encode(16969, "foobar"); });
    assert.throws(function(){return cptable.utils.decode(16969, [0x20]); });
  });
  it('should fail when presented with invalid char codes', function() {
    assert.throws(function(){cptable.utils.cache.decache(); return cptable.utils.encode(20127, [String.fromCharCode(0xAA)]);});
  });
  it('should fail to propagate UTF8 BOM in UTF7', function() {
    ["+/v8-abc", "+/v9"].forEach(function(m) { assert.throws(function() {
      assert.equal(m, cptable.utils.encode(65000, cptable.utils.decode(65000, m)));
    }); });
  });
});