git ssb

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var h = require('mutant/h')
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var pull = require('pull-stream')
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var mime = require('simple-mime')('application/octect-stream')
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var split = require('split-buffer')
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var nest = require('depnest')
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module.exports = {
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  needs: nest({
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    'sbot.async.addBlob': 'first'
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  }),
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  gives: nest('blob.html.input'),
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  create: function (api) {
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    return nest('blob.html.input', function FileInput (onAdded, opts = {}) {
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      return h('input', {
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        accept: opts.accept,
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        type: 'file',
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        'ev-change': function (ev) {
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          var file = ev.target.files[0]
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          if (!file) return
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          var mimeType = mime(file.name)
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          var fileName = file.name
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          // handle exif orientation data and resize
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          getOrientation(file, (orientation) => {
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            if (orientation >= 3 || opts.resize) {
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              getImage(file, (image) => {
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                image = rotate(image, orientation)
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                if (opts.resize) {
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                  image = resize(image, opts.resize.width, opts.resize.height)
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                }
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                if (image.toBlob) {
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                  if (mimeType !== 'image/jpeg' || mimeType !== 'image/png') {
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                    mimeType = 'image/jpeg'
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                  }
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                  image.toBlob(blob => {
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                    next(blob)
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                  }, mimeType, 0.85)
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                } else {
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                  next(file)
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                }
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              })
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            } else {
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              // don't process
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              next(file)
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            }
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          })
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          function next (file) {
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            var reader = new global.FileReader()
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            reader.onload = function () {
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              var stream = pull.values(split(new Buffer(reader.result), 64 * 1024))
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              api.sbot.async.addBlob(stream, function (err, blob) {
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                if (err) return console.error(err)
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                onAdded({
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                  link: blob,
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                  name: fileName,
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                  size: reader.result.length || reader.result.byteLength,
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                  type: mimeType
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                })
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              })
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            }
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            reader.readAsArrayBuffer(file)
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          }
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        }
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      })
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    })
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  }
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}
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function getImage (file, cb) {
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  var image = document.createElement('img')
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  image.onload = () => cb(image)
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  image.src = global.URL.createObjectURL(file)
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  image.style.display = 'block'
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  if (image.complete) cb(image)
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}
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function resize (image, width, height) {
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  var imageHeight = image.height
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  var imageWidth = image.width
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  var multiplier = (height / image.height)
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  if (multiplier * imageWidth < width) {
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    multiplier = width / image.width
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  }
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  var finalWidth = imageWidth * multiplier
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  var finalHeight = imageHeight * multiplier
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  var offsetX = (finalWidth - width) / 2
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  var offsetY = (finalHeight - height) / 2
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  var canvas = document.createElement('canvas')
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  canvas.width = width
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  canvas.height = height
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  var ctx = canvas.getContext('2d')
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  ctx.drawImage(image, -offsetX, -offsetY, finalWidth, finalHeight)
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  return canvas
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}
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function getOrientation (file, callback) {
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  var reader = new global.FileReader()
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  reader.onload = function (e) {
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    var view = new DataView(e.target.result)
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    if (view.getUint16(0, false) !== 0xFFD8) return callback(-2)
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    var length = view.byteLength
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    var offset = 2
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    while (offset < length) {
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      var marker = view.getUint16(offset, false)
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      offset += 2
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      if (marker === 0xFFE1) {
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        if (view.getUint32(offset += 2, false) !== 0x45786966) return callback(-1)
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        var little = view.getUint16(offset += 6, false) === 0x4949
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        offset += view.getUint32(offset + 4, little)
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        var tags = view.getUint16(offset, little)
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        offset += 2
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        for (var i = 0; i < tags; i++) {
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          if (view.getUint16(offset + (i * 12), little) === 0x0112) {
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            return callback(view.getUint16(offset + (i * 12) + 8, little))
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          }
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        }
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      } else if ((marker & 0xFF00) !== 0xFF00) {
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        break
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      } else {
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        offset += view.getUint16(offset, false)
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      }
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    }
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    return callback(-1)
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  }
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  reader.readAsArrayBuffer(file)
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}
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function rotate (img, orientation) {
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  var canvas = document.createElement('canvas')
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  var ctx = canvas.getContext('2d')
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  if (orientation === 6 || orientation === 8) {
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    canvas.width = img.height
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    canvas.height = img.width
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    ctx.translate(img.height / 2, img.width / 2)
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    if (orientation === 6) {
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      ctx.rotate(0.5 * Math.PI)
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    } else {
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      ctx.rotate(1.5 * Math.PI)
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    }
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  } else if (orientation === 3) {
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    canvas.width = img.width
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    canvas.height = img.height
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    ctx.rotate(1 * Math.PI)
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    ctx.translate(img.width / 2, img.height / 2)
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  } else {
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    return img
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  }
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  ctx.drawImage(img, -img.width / 2, -img.height / 2)
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  return canvas
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}
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