// Copyright Joyent, Inc. and other Node contributors.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and associated documentation files (the
// "Software"), to deal in the Software without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Software, and to permit
// persons to whom the Software is furnished to do so, subject to the
// following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Software.
//
// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
// OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
// MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN
// NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM,
// DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
// OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
// USE OR OTHER DEALINGS IN THE SOFTWARE.

var sketchSpecifics = require('./sketch-specifics')

// we only expose the posix implementation since Sketch only runs on macOS

var CHAR_FORWARD_SLASH = 47
var CHAR_DOT = 46

// Resolves . and .. elements in a path with directory names
function normalizeString(path, allowAboveRoot) {
  var res = ''
  var lastSegmentLength = 0
  var lastSlash = -1
  var dots = 0
  var code
  for (var i = 0; i <= path.length; i += 1) {
    if (i < path.length) code = path.charCodeAt(i)
    else if (code === CHAR_FORWARD_SLASH) break
    else code = CHAR_FORWARD_SLASH
    if (code === CHAR_FORWARD_SLASH) {
      if (lastSlash === i - 1 || dots === 1) {
        // NOOP
      } else if (lastSlash !== i - 1 && dots === 2) {
        if (
          res.length < 2 ||
          lastSegmentLength !== 2 ||
          res.charCodeAt(res.length - 1) !== CHAR_DOT ||
          res.charCodeAt(res.length - 2) !== CHAR_DOT
        ) {
          if (res.length > 2) {
            var lastSlashIndex = res.lastIndexOf('/')
            if (lastSlashIndex !== res.length - 1) {
              if (lastSlashIndex === -1) {
                res = ''
                lastSegmentLength = 0
              } else {
                res = res.slice(0, lastSlashIndex)
                lastSegmentLength = res.length - 1 - res.lastIndexOf('/')
              }
              lastSlash = i
              dots = 0
              continue
            }
          } else if (res.length === 2 || res.length === 1) {
            res = ''
            lastSegmentLength = 0
            lastSlash = i
            dots = 0
            continue
          }
        }
        if (allowAboveRoot) {
          if (res.length > 0) res += '/..'
          else res = '..'
          lastSegmentLength = 2
        }
      } else {
        if (res.length > 0) res += '/' + path.slice(lastSlash + 1, i)
        else res = path.slice(lastSlash + 1, i)
        lastSegmentLength = i - lastSlash - 1
      }
      lastSlash = i
      dots = 0
    } else if (code === CHAR_DOT && dots !== -1) {
      ++dots
    } else {
      dots = -1
    }
  }
  return res
}

function _format(sep, pathObject) {
  var dir = pathObject.dir || pathObject.root
  var base =
    pathObject.base || (pathObject.name || '') + (pathObject.ext || '')
  if (!dir) {
    return base
  }
  if (dir === pathObject.root) {
    return dir + base
  }
  return dir + sep + base
}

var posix = {
  // path.resolve([from ...], to)
  resolve: function resolve() {
    var resolvedPath = ''
    var resolvedAbsolute = false
    var cwd

    for (var i = arguments.length - 1; i >= -1 && !resolvedAbsolute; i -= 1) {
      var path
      if (i >= 0) {
        path = arguments[i]
      } else {
        if (cwd === undefined) {
          cwd = posix.dirname(sketchSpecifics.cwd())
        }
        path = cwd
      }

      path = sketchSpecifics.getString(path, 'path')

      // Skip empty entries
      if (path.length === 0) {
        continue
      }

      resolvedPath = path + '/' + resolvedPath
      resolvedAbsolute = path.charCodeAt(0) === CHAR_FORWARD_SLASH
    }

    // At this point the path should be resolved to a full absolute path, but
    // handle relative paths to be safe (might happen when process.cwd() fails)

    // Normalize the path
    resolvedPath = normalizeString(resolvedPath, !resolvedAbsolute)

    if (resolvedAbsolute) {
      if (resolvedPath.length > 0) return '/' + resolvedPath
      else return '/'
    } else if (resolvedPath.length > 0) {
      return resolvedPath
    } else {
      return '.'
    }
  },

  normalize: function normalize(path) {
    path = sketchSpecifics.getString(path, 'path')

    if (path.length === 0) return '.'

    var isAbsolute = path.charCodeAt(0) === CHAR_FORWARD_SLASH
    var trailingSeparator =
      path.charCodeAt(path.length - 1) === CHAR_FORWARD_SLASH

    // Normalize the path
    path = normalizeString(path, !isAbsolute)

    if (path.length === 0 && !isAbsolute) path = '.'
    if (path.length > 0 && trailingSeparator) path += '/'

    if (isAbsolute) return '/' + path
    return path
  },

  isAbsolute: function isAbsolute(path) {
    path = sketchSpecifics.getString(path, 'path')
    return path.length > 0 && path.charCodeAt(0) === CHAR_FORWARD_SLASH
  },

  join: function join() {
    if (arguments.length === 0) return '.'
    var joined
    for (var i = 0; i < arguments.length; i += 1) {
      var arg = arguments[i]
      arg = sketchSpecifics.getString(arg, 'path')
      if (arg.length > 0) {
        if (joined === undefined) joined = arg
        else joined += '/' + arg
      }
    }
    if (joined === undefined) return '.'
    return posix.normalize(joined)
  },

  relative: function relative(from, to) {
    from = sketchSpecifics.getString(from, 'from path')
    to = sketchSpecifics.getString(to, 'to path')

    if (from === to) return ''

    from = posix.resolve(from)
    to = posix.resolve(to)

    if (from === to) return ''

    // Trim any leading backslashes
    var fromStart = 1
    for (; fromStart < from.length; fromStart += 1) {
      if (from.charCodeAt(fromStart) !== CHAR_FORWARD_SLASH) break
    }
    var fromEnd = from.length
    var fromLen = fromEnd - fromStart

    // Trim any leading backslashes
    var toStart = 1
    for (; toStart < to.length; toStart += 1) {
      if (to.charCodeAt(toStart) !== CHAR_FORWARD_SLASH) break
    }
    var toEnd = to.length
    var toLen = toEnd - toStart

    // Compare paths to find the longest common path from root
    var length = fromLen < toLen ? fromLen : toLen
    var lastCommonSep = -1
    var i = 0
    for (; i <= length; i += 1) {
      if (i === length) {
        if (toLen > length) {
          if (to.charCodeAt(toStart + i) === CHAR_FORWARD_SLASH) {
            // We get here if `from` is the exact base path for `to`.
            // For example: from='/foo/bar'; to='/foo/bar/baz'
            return to.slice(toStart + i + 1)
          } else if (i === 0) {
            // We get here if `from` is the root
            // For example: from='/'; to='/foo'
            return to.slice(toStart + i)
          }
        } else if (fromLen > length) {
          if (from.charCodeAt(fromStart + i) === CHAR_FORWARD_SLASH) {
            // We get here if `to` is the exact base path for `from`.
            // For example: from='/foo/bar/baz'; to='/foo/bar'
            lastCommonSep = i
          } else if (i === 0) {
            // We get here if `to` is the root.
            // For example: from='/foo'; to='/'
            lastCommonSep = 0
          }
        }
        break
      }
      var fromCode = from.charCodeAt(fromStart + i)
      var toCode = to.charCodeAt(toStart + i)
      if (fromCode !== toCode) break
      else if (fromCode === CHAR_FORWARD_SLASH) lastCommonSep = i
    }

    var out = ''
    // Generate the relative path based on the path difference between `to`
    // and `from`
    for (i = fromStart + lastCommonSep + 1; i <= fromEnd; i += 1) {
      if (i === fromEnd || from.charCodeAt(i) === CHAR_FORWARD_SLASH) {
        if (out.length === 0) out += '..'
        else out += '/..'
      }
    }

    // Lastly, append the rest of the destination (`to`) path that comes after
    // the common path parts
    if (out.length > 0) return out + to.slice(toStart + lastCommonSep)
    else {
      toStart += lastCommonSep
      if (to.charCodeAt(toStart) === CHAR_FORWARD_SLASH) toStart += 1
      return to.slice(toStart)
    }
  },

  toNamespacedPath: function toNamespacedPath(path) {
    // Non-op on posix systems
    return path
  },

  dirname: function dirname(path) {
    path = sketchSpecifics.getString(path, 'path')
    if (path.length === 0) return '.'
    var code = path.charCodeAt(0)
    var hasRoot = code === CHAR_FORWARD_SLASH
    var end = -1
    var matchedSlash = true
    for (var i = path.length - 1; i >= 1; i -= 1) {
      code = path.charCodeAt(i)
      if (code === CHAR_FORWARD_SLASH) {
        if (!matchedSlash) {
          end = i
          break
        }
      } else {
        // We saw the first non-path separator
        matchedSlash = false
      }
    }

    if (end === -1) return hasRoot ? '/' : '.'
    if (hasRoot && end === 1) return '//'
    return path.slice(0, end)
  },

  basename: function basename(path, ext) {
    if (ext !== undefined)
      ext = sketchSpecifics.getString(ext, 'ext')
    path = sketchSpecifics.getString(path, 'path')

    var start = 0
    var end = -1
    var matchedSlash = true
    var i

    if (ext !== undefined && ext.length > 0 && ext.length <= path.length) {
      if (ext.length === path.length && ext === path) return ''
      var extIdx = ext.length - 1
      var firstNonSlashEnd = -1
      for (i = path.length - 1; i >= 0; i -= 1) {
        var code = path.charCodeAt(i)
        if (code === CHAR_FORWARD_SLASH) {
          // If we reached a path separator that was not part of a set of path
          // separators at the end of the string, stop now
          if (!matchedSlash) {
            start = i + 1
            break
          }
        } else {
          if (firstNonSlashEnd === -1) {
            // We saw the first non-path separator, remember this index in case
            // we need it if the extension ends up not matching
            matchedSlash = false
            firstNonSlashEnd = i + 1
          }
          if (extIdx >= 0) {
            // Try to match the explicit extension
            if (code === ext.charCodeAt(extIdx)) {
              if (--extIdx === -1) {
                // We matched the extension, so mark this as the end of our path
                // component
                end = i
              }
            } else {
              // Extension does not match, so our result is the entire path
              // component
              extIdx = -1
              end = firstNonSlashEnd
            }
          }
        }
      }

      if (start === end) end = firstNonSlashEnd
      else if (end === -1) end = path.length
      return path.slice(start, end)
    } else {
      for (i = path.length - 1; i >= 0; --i) {
        if (path.charCodeAt(i) === CHAR_FORWARD_SLASH) {
          // If we reached a path separator that was not part of a set of path
          // separators at the end of the string, stop now
          if (!matchedSlash) {
            start = i + 1
            break
          }
        } else if (end === -1) {
          // We saw the first non-path separator, mark this as the end of our
          // path component
          matchedSlash = false
          end = i + 1
        }
      }

      if (end === -1) return ''
      return path.slice(start, end)
    }
  },

  extname: function extname(path) {
    path = sketchSpecifics.getString(path, 'path')
    var startDot = -1
    var startPart = 0
    var end = -1
    var matchedSlash = true
    // Track the state of characters (if any) we see before our first dot and
    // after any path separator we find
    var preDotState = 0
    for (var i = path.length - 1; i >= 0; --i) {
      var code = path.charCodeAt(i)
      if (code === CHAR_FORWARD_SLASH) {
        // If we reached a path separator that was not part of a set of path
        // separators at the end of the string, stop now
        if (!matchedSlash) {
          startPart = i + 1
          break
        }
        continue
      }
      if (end === -1) {
        // We saw the first non-path separator, mark this as the end of our
        // extension
        matchedSlash = false
        end = i + 1
      }
      if (code === CHAR_DOT) {
        // If this is our first dot, mark it as the start of our extension
        if (startDot === -1) startDot = i
        else if (preDotState !== 1) preDotState = 1
      } else if (startDot !== -1) {
        // We saw a non-dot and non-path separator before our dot, so we should
        // have a good chance at having a non-empty extension
        preDotState = -1
      }
    }

    if (
      startDot === -1 ||
      end === -1 ||
      // We saw a non-dot character immediately before the dot
      preDotState === 0 ||
      // The (right-most) trimmed path component is exactly '..'
      (preDotState === 1 && startDot === end - 1 && startDot === startPart + 1)
    ) {
      return ''
    }
    return path.slice(startDot, end)
  },

  format: function format(pathObject) {
    if (pathObject === null || typeof pathObject !== 'object') {
      throw new Error('pathObject should be an Object')
    }
    return _format('/', pathObject)
  },

  parse: function parse(path) {
    path = sketchSpecifics.getString(path, 'path')

    var ret = { root: '', dir: '', base: '', ext: '', name: '' }
    if (path.length === 0) return ret
    var code = path.charCodeAt(0)
    var isAbsolute = code === CHAR_FORWARD_SLASH
    var start
    if (isAbsolute) {
      ret.root = '/'
      start = 1
    } else {
      start = 0
    }
    var startDot = -1
    var startPart = 0
    var end = -1
    var matchedSlash = true
    var i = path.length - 1

    // Track the state of characters (if any) we see before our first dot and
    // after any path separator we find
    var preDotState = 0

    // Get non-dir info
    for (; i >= start; --i) {
      code = path.charCodeAt(i)
      if (code === CHAR_FORWARD_SLASH) {
        // If we reached a path separator that was not part of a set of path
        // separators at the end of the string, stop now
        if (!matchedSlash) {
          startPart = i + 1
          break
        }
        continue
      }
      if (end === -1) {
        // We saw the first non-path separator, mark this as the end of our
        // extension
        matchedSlash = false
        end = i + 1
      }
      if (code === CHAR_DOT) {
        // If this is our first dot, mark it as the start of our extension
        if (startDot === -1) startDot = i
        else if (preDotState !== 1) preDotState = 1
      } else if (startDot !== -1) {
        // We saw a non-dot and non-path separator before our dot, so we should
        // have a good chance at having a non-empty extension
        preDotState = -1
      }
    }

    if (
      startDot === -1 ||
      end === -1 ||
      // We saw a non-dot character immediately before the dot
      preDotState === 0 ||
      // The (right-most) trimmed path component is exactly '..'
      (preDotState === 1 && startDot === end - 1 && startDot === startPart + 1)
    ) {
      if (end !== -1) {
        if (startPart === 0 && isAbsolute)
          ret.base = ret.name = path.slice(1, end)
        else ret.base = ret.name = path.slice(startPart, end)
      }
    } else {
      if (startPart === 0 && isAbsolute) {
        ret.name = path.slice(1, startDot)
        ret.base = path.slice(1, end)
      } else {
        ret.name = path.slice(startPart, startDot)
        ret.base = path.slice(startPart, end)
      }
      ret.ext = path.slice(startDot, end)
    }

    if (startPart > 0) ret.dir = path.slice(0, startPart - 1)
    else if (isAbsolute) ret.dir = '/'

    return ret
  },

  sep: '/',
  delimiter: ':',
  win32: null,
  posix: null,

  resourcePath: sketchSpecifics.resourcePath,
}

module.exports = posix
module.exports.posix = posix
