#!/usr/bin/env bash

set -e

# Requirements:
#    sudo apt-get install xclip


# e.g. 1908 ROLL
# ./start_dartium_roll.sh --verbose --directory ~/dartium-roll --old-branch 1847 --old-revision 251904 --new-branch 1908 --new-revision 259084 --chrome --pre-roll
# ./start_dartium_roll.sh --verbose --directory ~/dartium-roll --old-branch 1847 --old-revision 251904 --new-branch 1908 --new-revision 259084 --chrome --roll
# ./start_dartium_roll.sh --verbose --directory ~/dartium-roll --old-branch 1847 --old-revision 251904 --new-branch 1908 --new-revision 259084 --chrome --info
# ./start_dartium_roll.sh --verbose --directory ~/dartium-roll --old-branch 1847 --old-revision 167304 --new-branch 1908 --new-revision 169907 --blink --pre-roll
# ./start_dartium_roll.sh --verbose --directory ~/dartium-roll --old-branch 1847 --old-revision 167304 --new-branch 1908 --new-revision 169907 --blink --roll
# ./start_dartium_roll.sh --verbose --directory ~/dartium-roll --old-branch 1847 --old-revision 167304 --new-branch 1908 --new-revision 169907 --blink --info

# e.g., 1916 ROLL
# ~/./start_dartium_roll.sh --verbose --directory /media/TB/dartium-1916 --old-branch 1908 --old-revision 259084 --new-branch 1916 --new-revision 260298 --chrome --pre-roll

# ~/./start_dartium_roll.sh --verbose --directory /media/TB/dartium-1916 --old-branch 1908 --old-revision 169907 --new-branch 1916 --new-revision 170313 --blink --pre-roll

setglobal E_INVALID_ARG = '128'

proc usage {
  echo "Usage: $0 [--options]"
  echo "Options:"
  echo "  --[no-]verbose:           display information about each step"
  echo "  --directory base:         base directory of local git repository"
  echo "                            (e.g., ~/dartium-roll implies directory"
  echo "                            ~/dartium-roll/src and"
  echo "                            ~/dartium-roll/src/third_party/WebKit)**"
  echo "  --chrome:                 for the Chrome branch (not with --blink)**"
  echo "  --blink:                  for the Blink branch (not with --chrome)**"
  echo "  --old-branch name:        name of previous true branch (e.g., use 1847"
  echo "                            for version 34.0.1847.92) *"
  echo "  --old-revision revision:  revision of base trunk for $OLD version *"
  echo "  --new-branch name:        name of new true branch to create *"
  echo "  --new-revision revision:  revision of base trunk for new branch *"
  echo "  --pre-roll:               display commands to prepare for the roll"
  echo "  --roll:                   display Git commands to execute for creating"
  echo "                            branches for the roll"
  echo "  --info:                   display hashes for $BASE and $LAST on each"
  echo "                            branch (stripped$OLD, trunkdata$OLD, and"
  echo "                            trunkdata$NEW)"
  echo "  --help:                   this message"
  echo
  echo "* - required"
  echo
  echo "*  Script will prompt interactively if options not given."
  echo "** Argument must be specified."
  echo
  exit 1
}


proc verbose_message {
  if test $do_verbose = 1 {
    if test $(1) = "" {
      echo
    } else {
      echo -e "...$(1)..."
    }
  }
}


# Does the file src/.git/config contains the added lines pointing to the chrome
# remote dart$OLD and dart$NEW branches for src/ (e.g, dart1847 and dart1908):
#
#     [svn-remote "dart$OLD"]
#             url = svn://svn.chromium.org/chrome/branches/dart/$OLD/src
#             fetch = :refs/remotes/dart1847
#     [svn-remote "dart$NEW"]
#             url = svn://svn.chromium.org/chrome/branches/dart/$NEW/src
#             fetch = :refs/remotes/dart1908
#
# and does the file src/third_party/WebKit/.git/config contains the added lines
# for blink:
#
#     [svn-remote "dart$OLD"]
#             url = svn://svn.chromium.org/blink/branches/dart/$OLD/src
#             fetch = :refs/remotes/dart1847
#     [svn-remote "dart$NEW"]
#             url = svn://svn.chromium.org/blink/branches/dart/$NEW/src
#             fetch = :refs/remotes/dart1908
#
proc validate_remotes {
  verbose_message "Validating Remotes"

  if test $do_which = "chrome" {
    # Ensure remote for old Dartium release exist (e.g., remotes/dart1847)
    setglobal remote_dart_last = $[git branch -a | grep "remotes/dart$(do_old_branch)]
    # Ensure remote for new Dartium release exist (e.g., remotes/dart1908)
    setglobal remote_dart_new = $[git branch -a | grep "remotes/dart$(do_new_branch)]
    if test $remote_dart_last = "" {
      $[display_error "missing old remotes/dart$(do_old_branch)]
      exit -1
    }
    if test $remote_dart_new = "" {
      $[display_error "missing new remotes/dart$(do_new_branch)]
      exit -1
    }
  } elif test $do_which = "blink" {
    # Ensure remote for old Dartium release exist (e.g., remotes/dart1847)
    setglobal remote_dart_last = $[git branch -a | grep "remotes/blink-svn/$(do_old_branch)]
    # Ensure remote for new Dartium release exist (e.g., remotes/dart1908)
    setglobal remote_dart_new = $[git branch -a | grep "remotes/blink-svn/multivm-$(do_new_branch)]

    if test $remote_dart_last = "" {
      $[display_error "missing old remotes/blink-svn/$(do_old_branch)]
      exit -1
    }
    if test $remote_dart_new = "" {
      $[display_error "missing new remotes/blink-svn/multivm-$(do_new_branch)]
      exit -1
    }
  } else {
    $[display_error "--chrome or --blink must be specified]
    exit -1
  }
}

proc stripped_exist {
  var branch_name = $[git branch --no-color --list $[stripped_name] | sed 's/^[ \t\*]*//]
  echo $branch_name
}

# Does the branch trunkdart$OLD or trunkdart$NEW exist where $OLD is previous
# branch (e.g. 1847) and $NEW is new branch to roll (e.g., 1908)
# $(trunk_exist ${do_old_branch})  or  $(trunk_exist ${do_new_branch})
# Strip out the spaces and * (implies current branch) then return the branch name.
proc trunk_exist {
  var branch_name = $[git branch --list --no-color trunkdart$(1) | sed 's/^[ \t\*]*//' | tail -n 1]
  echo $branch_name
}

proc validate_repository {
  verbose_message "Validating Repository"

  setglobal strip_branch = $(stripped_name)

  # Validate that branches exist.
  setglobal stripped_found = $(stripped_exist)
  setglobal old_branch_found = $[trunk_exist $(do_old_branch)]
  setglobal new_branch_found = $[trunk_exist $(do_new_branch)]

  if test $stripped_found != "" {
    $[display_error "branch $(strip_branch) already exist]
    exit -1
  }

  if test $old_branch_found != "" {
    $[display_error "branch trunkdart$(do_old_branch) already exist]
    exit -1
  }

  if test $new_branch_found != "" {
    $[display_error "branch trunkdart$(do_new_branch) already exist]
    exit -1
 }
}

proc display_error {
  echo -e "\n\e[1;31mERROR: $(1)\e[0m\n" > !2
  exit 1
}


# Given a revision number $1 return the trunk's hash code for that revision.
proc hash_trunk_revision {
  # Chrome trunk hash code for [NewChromeCommit]
  setglobal hash_trunk = $[git log master --grep=src@$(1) --pretty=format:'%H' -n 1]
}


# Return the last revision for a branch.  Used by new trunk roll for the
# DEPS file for the last revision to use during build.
proc last_revision {
  echo $[git svn log $(1) --oneline -1 | cut -d '|' -f1 | sed "s/r//]
}


# Return the branch for strippedOOOO use bash line:
#    $(stripped_name)
proc stripped_name {
  echo "stripped$(do_old_branch)"
}


# Give a branch name return the trunk release for that branch.
proc trunkdart_name {
  echo "trunkdart$(1)"
}


# Compute the hash codes for the previous branch hash_base is the first commit
# and hash_last is final commit.
proc hash_codes_base_last {
  # Get the first commit for previous Dartium roll on chrome branch.
  setglobal hash_base = $[git rev-list $(1) --pretty=format:'%H' | tail -n 1]

  # Get the last commit for previous Dartium roll on chrome branch.
  setglobal hash_last = $[git log $(1) --pretty=format:'%H' -1]
}


# Compute the hash codes for the previous branch hash_base is the first commit
# and hash_last is final commit.
proc hash_codes_base2_last2 {
  # Get the last commit for previous Dartium roll on chrome branch.
  setglobal hash_last2 = $[git log $(1) --pretty=format:'%H' -1]

  var search = ''
  if test $do_which = "chrome" {
    set search = ""chrome/trunk/src@$(do_old_revision)""
  } else {
    set search = ""blink/branches/dart/multivm-$(do_new_revision)@$(do_old_revision)""
  }

  # Get the first commit for previous Dartium roll on chrome branch.
  setglobal hash_base2 = $[git log $(1) --grep=@$(do_old_revision) --pretty=format:'%H' | tail -1]
}


# Pad right/left up to 80 spaces.
#   Parameter $1 string to pad.
#   Parameter $2 is max length to post-pad with spaces.
#   Parameter $3 if specified padd to the right otherwise pad to the right.
#   Returns string right padded with spaces.
proc space_pad {
  var spaces = $[printf '%0.1s' " "{1..80}]
  var spaces_pad = $(spaces:0:$2)
  var padding = $[printf "%s" $(spaces_pad:${#1})]

  if [[ "$3" = "" ]] {
    # Pad to the right [default].
    echo "$(1)$(padding)"
  } else {
    # Pad to the left.
    echo "$(padding)$(1)"
  }
}


# Format the line '|  URL:  <url>   |'.
#   Paramter $1 - url to format
#   Returns the formatted and space padded line for display_hashes.
proc display_url {
  # Line length is 65, skipped # 9 characters at beginning '|  URL:  '
  # and last character '|'. Up to 55 characters of padding.
  var format_url = $[space_pad $1 55]
  var valid_url = $[valid_branch_url $1]
  if [[ "$valid_url" = "" ]] {
    # Error format padding is same as above remote_url 55;
    var format_err = $[space_pad "WARNING ON TRUNK - FIX IMMEDIATELY" 55]
    # Output in red, the problem, both lines the URL and the warning message.
    echo -e "|  URL:  \e[1;31m$(format_url)\e[0m|\n|        \e[1;31m$(format_err)\e[0m|"
  } else {
    # URL looks good.
    echo "|  URL:  $(format_url)|"
  }
}


proc display_hashes {
  if test $do_info_hashes = 1 {
    var format_which = $[space_pad $do_which 6 1]
    setglobal stripped_branch = $[stripped_name]
    # stripped$OLD found
    setglobal stripped_found = $[stripped_exist]
    if test $stripped_found != "" {
      hash_codes_base_last $(stripped_branch)
      hash_trunk_revision $(do_old_revision)
      # Display the first/last commit hash for stripped$OLD branch and the
      # trunk hash for $OLD@do_last_revsion.
      echo "================================================================="
      var format_branch = $[space_pad $stripped_branch 32 1]
      echo "|  \$OLD: $(format_which) dart$(do_old_branch)@$(do_old_revision)$(format_branch) |"
      var remote_url = $[url_branch $stripped_branch]

# TODO(terry): Testing failure below remove before checkin
#      local remote_url=$(url_branch "master")

      echo $[display_url $remote_url]
      echo "|---------------------------------------------------------------|"
      var format_hash = $[space_pad $hash_base 51]
      echo "|  \$BASE  | $(format_hash) |"
      echo "|---------------------------------------------------------------|"
      set format_hash = $[space_pad $hash_last 51]
      echo "|  \$LAST  | $(format_hash) |"
      echo "================================================================="
      echo
    } else {
      echo "$(stripped_branch) not found"
      echo
    }

    # trunkdart$OLD found
    setglobal branch_trunkdart_old = $[trunkdart_name $(do_old_branch)]
    setglobal old_branch_found = $[trunk_exist $(do_old_branch)]
    if test $old_branch_found != "" {
      hash_codes_base2_last2 $(branch_trunkdart_old)
      hash_trunk_revision $(do_old_revision)
      # Display the first/last commit hash for trunkdart$OLD branch and the
      # trunk hash for $OLD@do_last_revsion.
      echo "================================================================="
      var format_branch = $[space_pad $branch_trunkdart_old 32 1]
      echo "|  \$OLD  $(format_which) dart$(do_old_branch)@$(do_old_revision)$(format_branch) |"
      var remote_url = $[url_branch $branch_trunkdart_old]
      echo $[display_url $remote_url]
      echo "|---------------------------------------------------------------|"
      var format_base2 = $[space_pad $hash_base2 51]
      echo "|  \$BASE2 | $(format_base2) |"
      echo "|---------------------------------------------------------------|"
      var format_last2 = $[space_pad $hash_last2 51]
      echo "|  \$LAST2 | $(format_last2) |"
      echo "================================================================="
      echo
    } else {
      echo "$(branch_trunkdart_old) not found"
      echo
    }

    # trunkdart$NEW found
    setglobal branch_trunkdart_new = $[trunkdart_name $(do_new_branch)]
    setglobal new_branch_found = $[trunk_exist $(do_new_branch)]
    if test $new_branch_found != "" {
      hash_trunk_revision $(do_new_revision)
      # Display the trunk hash for $NEW@do_new_revsion.
      echo "================================================================="
      var format_branch = $[space_pad $branch_trunkdart_new 32 1]
      echo "|  \$NEW  $(format_which) dart$(do_new_branch)@$(do_new_revision)$(format_branch) |"
      var remote_url = $[url_branch $branch_trunkdart_new]
      echo $[display_url $remote_url]
      echo "|---------------------------------------------------------------|"
      var revision = $[last_revision $branch_trunkdart_new]
      var format_revision = $[space_pad $revision 43]
      echo "|  last revision  | $(format_revision) |"
      echo "================================================================="
      echo
    } else {
      echo "$(branch_trunkdart_new) not found"
      echo
    }
  }
}


proc switch_branch {
  $[git checkout $(1) --quiet]
  var curr_branch = $[git name-rev --name-only HEAD]
  if [[ "$curr_branch" != "$1" ]] {
    $[display_error "Unable to switch to branch $1 - pending commits/add?]
    exit -1
  }
  echo $curr_branch
}


# Check that the branch is not pointing to either blink or chrome trunk.
# These branches should be pointing to either:
#     svn://svn.chromium.org/chrome/branches/dart/NNNN
#     svn://svn.chromium.org/blink/branches/dart/NNNN
#
# $1 parameter - branch-name to make current branch and check repository
#                name.
proc check_branch {
  var old_branch = $[git name-rev --name-only HEAD]
  var curr_branch = $[switch_branch $1]
  var trunk_url = '';

  if test $do_which = "chrome" {
    # Chrome
    set trunk_url = ''Committing to svn://svn.chromium.org/chrome/trunk/src ...''
  } elif test $do_which = "blink" {
    # Blink
    set trunk_url = ''Committing to svn://svn.chromium.org/blink/trunk ...''
  } else {
    $[display_error "Neither blink or chrome specified]
    exit -1
  }

  var remote_commit = $[git svn dcommit --dry-run | head -1 | grep $(trunk_url)]

  set curr_branch = $[switch_branch $old_branch]
  if [[ "$curr_branch" != "$old_branch" ]] {
    $[display_error "Unable to switch back to original branch $(old_branch)]
    exit -1
  }

  if [[ "$remote_commit" != "" ]] {
    $[display_error "Branch $(1) is NOT pointing to the Dart branch repository but pointing to trunk.]
    exit -1
  }

  echo "Local branch '$(1)' is based on the remote branch/dart repository."
}


# Given an URL of a remote repository passed as parameter $1 (e.g., from
# url_branch function) return the URL passed in if valid or return empty
# string "".
proc valid_branch_url {
  # Compute what the remote repository should be:
  #    svn://svn.chromium.org/${do_which}/branches/dart/${do_old_branch}/src
  #    e.g., svn://svn.chromium.org/chrome/branches/dart/1847/src
  # or blink:
  #    svn://svn.chromium.org/blink/branches/dart/${do_old_branch}
  #    e.g., svn://svn.chromium.org/blink/branches/dart/1847
  var src_dir = ''""
  if [[ "$do_which" = "chrome" ]] {
    set src_dir = '"/src'"
  }
  var old_remote = ""svn://svn.chromium.org/$(do_which)/branches/dart/$(do_old_branch)$(src_dir)""
  var new_remote = ""svn://svn.chromium.org/$(do_which)/branches/dart/$(do_new_branch)$(src_dir)""

  echo $[echo $1 | grep -e $(old_remote) -e $(new_remote)]
}


# Returns the remote repository URL associated with a branch.
# Parameter $1 is the branch name.
proc url_branch {
  var old_branch = $[git name-rev --name-only HEAD]
  var curr_branch = $[switch_branch $1]

  var remote_commit = $[git svn dcommit --dry-run | head -1 | sed 's/Committing to //' | sed 's/ ...//]

  set curr_branch = $[switch_branch $old_branch]

  echo $(remote_commit)
}


# Ensure that any created branches (stripped$OLD, trunkdart$OLD and
# trunkdart$NEW) are not pointing to either the blink or chrome trunks.
proc validate_branches {
  # stripped branch
  var stripped_found = $[stripped_exist]
  if test $stripped_found != "" {
    var branch_name = $[stripped_name]
    var check_result = $[check_branch $(branch_name)]
    printf "%s\n" $check_result
  }

  # trunkdart$OLD
  var branch_trunkdart_old = $[trunkdart_name $(do_old_branch)]
  var old_branch_found = $[trunk_exist $(do_old_branch)]
  if test $old_branch_found != "" {
    var check_result = $[check_branch $branch_trunkdart_old]
    printf "%s\n" $check_result
  }

  # trunkdart$NEW
  var branch_trunkdart_new = $[trunkdart_name $(do_new_branch)]
  var new_branch_found = $[trunk_exist $(do_new_branch)]
  if test $new_branch_found != "" {
    var check_result = $[check_branch $branch_trunkdart_new]
    printf "%s\n" $check_result
  }
}


proc display_roll_commands {
  if test $roll_branches = 1 {
    if test $do_which = "chrome" {
      roll_chrome_commands
    } elif test $do_which = "blink" {
      roll_blink_commands
    }
  }
}


# Show commands to create SVN branch folder and remote repository for new roll.
proc display_remote_repository_creation {
# TODO(terry): Use the diretory passed in instead of hard-coded dartium-NNNN
# TODO(terry): Should execute each command with a Y or N and command runs.
# TODO(terry): Echo output from commands especially clone and rebase using "OUTPUT=$(git cl rebase); echo $OUTPUT"
# TODO(terry): Add ability to copy to clipboard programmatically us 'echo "hi" | xclip -selection clipboard'
#              copies hi to clipboard.
  echo "Do the following pre-roll setup"
  if test $do_which = "chrome" {
    echo "  mkdir dartium-$(do_new_branch)"
    echo "  cd dartium-$(do_new_branch)"
    echo "  svn mkdir -m \"Preparing Chrome 35/$(do_new_branch) branch\" "\
         "svn://svn.chromium.org/chrome/branches/dart/$(do_new_branch)"
    echo "  svn cp -m \"Branching for $(do_new_branch) @$(do_new_revision)\" "\
         "svn://svn.chromium.org/chrome/trunk/src@$(do_new_revision) "\
         "svn://svn.chromium.org/chrome/branches/dart/$(do_new_branch)/src"
    echo "  git svn clone -r241107 svn://svn.chromium.org/chrome/trunk/src src"
    echo
    echo "  cd src"
    echo "  git cl rebase"
    echo
    echo "-----After rebase finishes-----"
    echo
    echo " 1. Add the below lines to src/.git/config"
    echo
    echo "[svn-remote \"dart$(do_old_branch)\"]"
    echo "      url = svn://svn.chromium.org/chrome/branches/dart/$(do_old_branch)/src"
    echo "      fetch = :refs/remotes/dart$(do_old_branch)"
    echo "[svn-remote \"dart$(do_new_branch)\"]"
    echo "      url = svn://svn.chromium.org/chrome/branches/dart/$(do_new_branch)/src"
    echo "      fetch = :refs/remotes/dart$(do_new_branch)"
    echo
    echo " 2. Get the code"
    echo
    echo "    cd src"
    echo "    git svn fetch dart$(do_old_branch) && git svn fetch dart$(do_new_branch)"
  } elif test $do_which = "blink" {
    echo "  Directory dartium-$(do_new_branch) exists."
    echo "  cd dartium-$(do_new_branch)"
    echo "  svn cp -m \"Branching $(do_new_branch) @$(do_new_revision)\" "\
         "svn://svn.chromium.org/blink/trunk@$(do_new_revision) "\
         "svn://svn.chromium.org/blink/branches/dart/$(do_new_branch)"

    echo "  git svn clone --trunk=trunk --branches=branches/dart"\
         " --prefix=blink-svn/ -r165883:HEAD " \
         "svn://svn.chromium.org/blink src/third_party/WebKit"
    echo
    echo "  cd src/third_party/WebKit"
    echo "  git cl rebase"
    echo
    echo "-----After rebase finishes-----"
    echo
    echo " 1. Add the below lines to src/third_party/WebKit/.git/config"
    echo
    echo "[svn-remote \"dart$(do_old_branch)\"]"
    echo "      url = svn://svn.chromium.org/blink/branches/dart/$(do_old_branch)"
    echo "      fetch = :refs/remotes/dart$(do_old_branch)"
    echo "[svn-remote \"dart$(do_new_branch)\"]"
    echo "      url = svn://svn.chromium.org/blink/branches/dart/$(do_new_branch)"
    echo "      fetch = :refs/remotes/dart$(do_new_branch)"
    echo
    echo " 2. Get the code"
    echo
    echo "    cd src/third_party/WebKit"
    #TODO(terry): Should the fetch be remotes/blink-svn/multivm-${do_new_branch}
    echo "    git svn fetch dart$(do_old_branch) && git svn fetch dart$(do_new_branch)"
  }
}

# Displays each of the 3 steps, of GIT commands, to create the
# branches for a Dartium roll.
#
# Givin the following Dartium roll information:
#   Previous Dartium roll 1847 @251094      ($OLD)
#   New Dartium roll to make 1908 @ 259084  ($NEW)
#
# Three branches will be created a stripped[$OLD], trunkdart[$OLD]
# and trunkdart[$NEW].
#
#  |==============================================|
#  | $OLD       |     1847                        |
#  |----------------------------------------------|
#  | $OLD_REV   |     251094                      |
#  |----------------------------------------------|
#  | $NEW       |     1908                        |
#  |----------------------------------------------|
#  | $NEW_REV   |     259084                      |
#  |==============================================|
#
# stripped$OLD  - Branch with upstream patches stripped out.
# trunkdart$OLD - Branch with all patches for $OLD.
# trunkdart$NEW - Branch of a new Chromium/Blink release with
#                 cherry-picked $OLD commits from trunkdart$OLD.
#
# stripped$OLD, trunkdart$OLD points the SVN remote repository
#
#    svn://svn.chromium.org/chrome/branches/dart/1847/src
#
# trunkdart$NEW points to the SVN remote repository
#    svn://svn.chromium.org/chrome/branches/dart/1908/src
#
# STEP 1.
# -------
# Create the stripped$OLD:
#     > git checkout -b stripped$OLD dart$OLD
#     > git rebase -i $BASE
#
#     e.g., git checkout -b stripped1847 dart1847
#           git rebase -i 3345f6a26911beda2ed352e887549bc514acb4bd
#
# Rebasing with -i will launch an editor, show all commits after $BASE and let
# you interactively remove any upstream commits from trunk.  Upstream commits
# have a format of "Incrementing VERSION to 32.0.1847.78".  Then save and quit
# the editor.
#
# $BASE and $LAST are computed by this script and is returned in the
# 'git rebase -i <hash-code>' command.
#
#      NOTE: How $BASE and $LAST are computed:
#      ---------------------------------------
#      $BASE, first commit in $OLD, is computed by:
#           > git rev-list stripped1847 --pretty=format:'%H' | tail -n 1
#      Return a GIT hash code e.g., 3345f6a26911beda2ed352e887549bc514acb4bd
#
#      $LAST, last commit in $NEW, is computed by:
#           > git log stripped1847 --pretty=format:'%H' -1
#      Return a GIT hash code e.g., 44d12cd4b7e041f8d06f8735f1af08abb66825c4
#
# STEP 2.
# -------
# Create the trunkdart$OLD e.g.,
#     > git checkout -b trunkdart$OLD $BASE
#     > git cherry-pick $BASE..$LAST
#
#     e.g., git checkout -b trunkdart1847
#
# Create branch trunkdart$OLD and reapplies all Dart-related work on $OLD (from
# the stripped branch created in Step1.).  This cherry-pick should not have any
# conflicts as you are rebasing onto exactly the same source code layout.
#
# STEP 3.
# -------
# Create the branch for $NEW (trunkdart$NEW):
#    > git checkout -b trunkdart$NEW dart$NEW
#    > git cherry-pick $BASE2..$LAST2
#
# Important points trunkdart$NEW is attached to the remote SVN repository created
# in pre-steps.
#
#    e.g., git checkout -b trunkdart1908 dart1908
#          git cherry-pick xxxx..xxxx
#
# $BASE2 should be the same as $BASE to validate with:
#
#    > git log trunkdart$OLD --grep=@$OLD_REV --pretty=format:'%H' | tail -1
#
#    e.g., git log trunkdart1847 --grep=251094 --pretty=format:'%H' | tail -1
#          3345f6a26911beda2ed352e887549bc514acb4bd
#
# $LAST2 is the last commit in $OLD in trunkdart$OLD computed by:
#
#    > git log trunkdart$OLD --pretty=format:'%H' -1
#
#    e.g., > git log trunkdart1847 --pretty=format:'%H' -1
#          2549d8ecd211ee6fed6699d70f319e077b425be4
#
# The we'll cherry-pick commits from $OLD.
#   e.g.,
#   > git cherry-pick 3345f6a26911beda2ed352e887549bc514acb4bd..2549d8ecd211ee6fed6699d70f319e077b425be4
#
# Cherry picking is an iterative process.  Each commit in the $OLD branch is
# applied to the $NEW branch any conflicts will need to fixed.
#
# Fix each file conflict(s) in a particular commit:
#
#   > vim <filename>
#   > git add <filename>
#
# When all file conflicts for a particular commit are done then:
#
#   > git commit -a -m "Merged $OLD"
#
# Continue the original cherry-picking
#   > git cherry-pick --continue
#
#
# ********************************************************************
# *                            IMPORTANT:                            *
# ********************************************************************
#
# When all commits are made to our new trunk (trunkdart$NEW).  Then try an
# initial dcommit with the --dry-run option.
#
#     > git svn dcommit --dry-run
#
#     e.g., git svn dcommit --dry-run
#           Committing to svn://svn.chromium.org/chrome/branches/dart/1908/src ...
#           diff-tree 48e85b5f247696c432d9dbb55c37f88f4df8a06a~1 48e85b5f247696c432d9dbb55c37f88f4df8a06a
#           ...
#
# It is important to check the first line "Committing to " the repository
# should be the new remote SVN e.g., svn://svn.chromium.org/chrome/branches/dart/1908/src ...
#
# IT SHOULD NOT BE "svn://svn.chromium.org/chrome/trunk/src ..." this will
# dcommit the changes to the chrome trunk and break the chromium build.
#
proc roll_chrome_commands {
  setglobal stripped_found = $[stripped_exist]
  setglobal old_branch_found = $[trunk_exist $(do_old_branch)]
  setglobal new_branch_found = $[trunk_exist $(do_new_branch)]

  echo
  echo "================================================"
  echo "|             git commands to run:             |"
  echo "================================================"

  setglobal remoteOld = "dart$(do_old_branch)"
  setglobal strip_branch = $[stripped_name]

  if test $stripped_found = "" {
    echo "------------------ Step 1. ---------------------"
    echo

    # Git command to create stripped old branch.
    echo "git checkout -b $(strip_branch) $(remoteOld)"

    # Get hashes for base for do_old_branch.
    hash_codes_base_last $(remoteOld)

    echo "git rebase -i $(hash_base)"
    echo
  } elif test $old_branch_found = "" {
    echo "------------------ Step 2. ---------------------"
    echo

    # Get hashes for base, last and base hash from trunk for the last branch.
    hash_codes_base_last $(strip_branch)

    # Git command to create old branch with only changes from base to last
    # commits for that branch.  Checkout based on stripped$OLD first commit
    # $BASE.
    setglobal branch_trunkdart_old = $[trunkdart_name $(do_old_branch)]
    echo "git checkout -b $(branch_trunkdart_old) $(hash_base)"

    echo "git cherry-pick $(hash_base)..$(hash_last)"
    echo
  } elif test $new_branch_found = "" {
    echo "------------------ Step 3. ---------------------"
    echo

    # Git command to create new branch to roll.
    setglobal branch_trunkdart_new = $[trunkdart_name $(do_new_branch)]

    # get base and last commit hashes of the trunkdart$OLD
    hash_codes_base2_last2 $(branch_trunkdart_old)

    echo "git checkout -b $(branch_trunkdart_new) $(remoteOld)"

    echo "git cherry-pick $(hash_base2)..$(hash_last2)"
    echo
  } else {
    echo "===== Nothing to do - Roll setup complete. ====="
  }

  echo "================================================"
}


proc roll_blink_commands {
  setglobal stripped_found = $[stripped_exist]
  setglobal old_branch_found = $[trunk_exist $(do_old_branch)]
  setglobal new_branch_found = $[trunk_exist $(do_new_branch)]

  echo
  echo "================================================"
  echo "|             git commands to run:             |"
  echo "================================================"

  setglobal remoteOld = "dart$(do_old_branch)"
  setglobal strip_branch = $[stripped_name]

  if test $stripped_found = "" {
    echo "------------------ Step 1. ---------------------"
    echo

    # Git command to create stripped old branch.
    echo "git checkout -b $(strip_branch) $(remoteOld)"

    # Get hashes for base dir do_old_branch.
    hash_codes_base_last $(remoteOld)

    eho "git rebase -i $(hash_base)"
    echo
  } elif test $old_branch_found = "" {
    echo "------------------ Step 2. ---------------------"
    echo

    # Get hashes for base, last and base hash from trunk for the last branch.
    hash_codes_base_last $(strip_branch)

    # Git command to create old branch with only changes from base to last
    # commits for that branch.  Checkout based on stripped$OLD first commit
    # $BASE.
    setglobal branch_trunkdart_old = $[trunkdart_name $(do_old_branch)]
    echo "git checkout -b $(branch_trunkdart_old) $(hash_base)"

    echo "git cherry-pick $(hash_base)..$(hash_last)"
    echo
  } elif test $new_branch_found = "" {
    echo "------------------ Step 3. ---------------------"
    echo


    # Git command to create new branch to roll.
    setglobal branch_trunkdart_new = $[trunkdart_name $(do_new_branch)]

    # get base and last commit hashes of the trunkdart$OLD
    hash_codes_base2_last2 $(branch_trunkdart_old)

    echo "git checkout -b $(branch_trunkdart_new) $(remoteOld)"

    echo "git cherry-pick $(hash_base2)..$(hash_last2)"
    echo
  } else {
    echo "===== Nothing to do - Roll setup complete. ====="
  }

  echo "================================================"
}


# checkout strippedOOOO and trunkdartNNNN
setglobal create_branches = '0'

setglobal do_info_hashes = '0'

setglobal base_dir = ''""

# Display the pre-roll commands; if specified nothing else is displayed.
setglobal do_pre_roll = '0'

# which branch chrome or blink
setglobal do_which = ''""

# Display detail information about all major steps
setglobal do_verbose = '0'

# $OLD branch
setglobal do_old_branch = ''""
setglobal do_old_revision = ''""

# $NEW branch
setglobal do_new_branch = ''""
setglobal do_new_revision = ''""

setglobal curr_switch = ''""
for var in [@Argv]
{
  match $var {
  with --help
    usage
    exit
    
  with --verbose
    setglobal do_verbose = '1'
    setglobal curr_switch = ''""
    
  with --no-verbose
    setglobal do_verbose = '0'
    setglobal curr_switch = ''""
    
  with --chrome
    if test $do_which != "" {
      $[display_error "--chrome can not be specified with --blink]
      exit $E_INVALID_ARG
    }
    setglobal do_which = '"chrome'"
    setglobal curr_switch = ''""
    
  with --blink
    if test $do_which != "" {
      $[display_error "--blink can not be specified with --chrome]
      exit $E_INVALID_ARG
    }
    setglobal do_which = '"blink'"
    setglobal curr_switch = ''""
    
  with --pre-roll
    setglobal do_pre_roll = '1'
    setglobal curr_switch = ''""
    
  with --roll
    setglobal roll_branches = '1'
    setglobal curr_switch = ''""
    
  with --info
    setglobal do_info_hashes = '1'
    setglobal curr_switch = ''""
    
  with --directory
    setglobal curr_switch = '"base-directory'"   # takes an argument.
    
  with --old-branch
    setglobal curr_switch = '"old-branch'"       # takes an argument.
    
  with --new-branch
    setglobal curr_switch = '"new-branch'"       # takes an argument.
    
  with --old-revision
    setglobal curr_switch = '"old-revision'"     # takes an argument.
    
  with --new-revision
    setglobal curr_switch = '"new-revision'"     # takes an argument.
    
  with *
    setglobal prefix = $(var:0:2)
    if test $prefix = "--" {
      $[display_error "unexpected switch $(var)]
      exit $E_INVALID_ARG
    }
    match $curr_switch {
      with base-directory
        setglobal base_dir = $(var)
        
      with old-branch
        setglobal do_old_branch = $(var)
        
      with old-revision
        setglobal do_old_revision = $(var)
        
      with new-branch
        setglobal do_new_branch = $(var)
        
      with new-revision
        setglobal do_new_revision = $(var)
        
      with *
        if test $curr_switch != "" {
          $[display_error "unexpected paramter for $(curr_switch)]
          exit $E_INVALID_ARG
        } else {
          $[display_error "unexpected switch $(var)]
          exit $E_INVALID_ARG
        }
        
    }
    setglobal curr_switch = ''""
    
  }
}

# Insure that everything is known otherwise prompt information.
if test $base_dir = "" {
  echo "--directory switch must be specified."
  exit $E_INVALID_ARG
}

if test $do_which == "" {
  echo "--chrome or --blink switch must be specified."
  exit $E_INVALID_ARG
}

if test $do_old_branch = "" {
  echo "Enter LAST $(do_which) true branch (e.g., Chrome version 34.0.1847.92 true branch is 1847)"
  read do_old_branch
}

if test $do_old_revision = "" {
  echo "Enter LAST $(do_which) base trunk revision #"
  read do_old_revision
}

if test $do_new_branch = "" {
  echo "Enter NEW $(do_which) true branch (e.g., Chrome version 35.0.1908.4 true branch is 1908)"
  read do_new_branch
}

if test $do_new_revision = "" {
  echo "Enter NEW $(do_which) base trunk revision #"
  read do_new_revision
}

echo
echo "Rolling new branch $(do_new_branch)@$(do_new_revision)"

verbose_message
verbose_message "Previous branch $(do_old_branch)@$(do_old_revision)"
verbose_message "New branch $(do_new_branch)@$(do_new_revision)"
verbose_message

if [[ "$do_pre_roll" = "1" ]] {
  display_remote_repository_creation
  exit 1
}

pushd . > /dev/null

if test $base_dir != "" {
  cd $(base_dir)
}

cd src

if test $do_which = "blink" {
  cd third_party/WebKit
}

# Disable ^C and ^Z while running script.
trap '' INT
trap '' TSTP

validate_remotes

display_roll_commands

display_hashes

# Insure that all local branches for the roll are NOT based on the chrome or
# blink trunks.
validate_branches

# Re-enable ^C and ^Z.
trap - INT
trap - TSTP

popd > /dev/null