" The purpose of creating this autoload is with functions like git_branch_log
" which opens another 'git' filetype buffer defining such a function in
" after/ftplugin/ft.vim results in a complain about duplicated function since
" anything defined there will be loaded again. See :help autoload.

" Delete the branch on the current line in the output of Git branch -a.
function! git#git_branch_delete() abort
  let line = trim(getline('.'))
  let branch = split(line, "/")
  if len(branch) == 1
    " Handles the case for local branch
    execute "Git branch -D " . branch[0]
  else
    " Handles the case for remote remotes/remote_name/branch_name
    let remote = branch[1]
    let branch = branch[2]
    execute "Git push -d " . remote . " " . branch
    execute "Git branch -D " . branch
  endif
  silent execute "bw"
endfunction

" Checkout the branch on the current line in the output of Git branch -a.
function! git#git_branch_checkout() abort
  let line = trim(getline('.'))
  let branch = split(line, "/")
  if len(branch) == 1
    " Handles the case for local branch
    silent execute "Git checkout " . branch[0]
  else
    " Handles the case for remote remotes/remote_name/branch_name
    let remote = join(branch[1:2], "/")
    silent execute "Git checkout " . remote
    silent execute "Git checkout -b " . branch[2]
  endif
  silent execute "bw"
endfunction

" Get the log of the branch on current line in the output of Git branch -a.
function! git#git_branch_log() abort
  let line = trim(getline('.'))
  let branch = split(line, "/")
  " Close the buffer opened by Git branch -a
  silent execute "bw"
  if len(branch) == 1
    " Handles the case for local branch
    execute "Git log " . branch[0]
  else
    " Handles the case for remote remotes/remote_name/branch_name
    let remote = join(branch[1:2], "/")
    execute "Git log " . remote
  endif
endfunction

" Get the log of the branch on current line in the output of Git branch -a.
" This one returns a log where a line has the form <SHA> <commit-msg>. This
" acts as a precursor to what we run cherry-pick on.
function! git#git_branch_log_pretty() abort
  let line = trim(getline('.'))
  let branch = split(line, "/")
  " Close the buffer opened by Git branch -a
  silent execute "bw"
  if len(branch) == 1
    " Handles the case for local branch
    execute "Git log --pretty=oneline --no-merges " . branch[0]
  else
    " Handles the case for remote remotes/remote_name/branch_name
    let remote = join(branch[1:2], "/")
    execute "Git log --pretty=oneline --no-merges " . remote
  endif
endfunction

" Run Git cherry-pick on the commit in the line which we are at. To be used
" after running some variation of Git log.
function! git#git_cherry_pick() abort
  " A line in Git log is of the form commit <SHA>
  let line = trim(getline('.'))
  let commit = split(line, " ")
  silent execute "Git cherry-pick " . commit[1]
endfunction

" Git cherry-pick a range of commits. To be run on output of Git log
" --pretty=oneline. See git_branch_log_pretty.
function! git#git_cherry_pick_range() abort
  let [lnum1, col1] = getpos("'<")[1:2]
  let [lnum2, col2] = getpos("'>")[1:2]
  let lines = reverse(getline(lnum1, lnum2))
  if len(lines) == 0
    return ''
  endif
  let oldCommit = split(lines[0], " ")[:0][0]
  let newCommit = split(lines[-1], " ")[:0][0]
  execute "Git cherry-pick " . oldCommit . "^.." . newCommit
  silent execute "bw"
endfunction

" Run Git difftool on the commit in the line which we are at. To be used after
" running some variation of Git log.
function! git#git_diff_commit() abort
  " A line in Git log is of the form commit <SHA>
  let line = trim(getline('.'))
  let commit = split(line, " ")
  silent execute "Git difftool -y " . commit[1] . "^!"
endfunction

" Run DiffviewOpen on the commit in the line which we are at. To be used after
" running some variation of Git log.
function! git#git_diffview_commit() abort
  " A line in Git log is of the form commit <SHA>
  let line = trim(getline('.'))
  let commit = split(line, " ")
  silent execute "DiffviewOpen " . commit[1] . "^!"
endfunction

" The next two functions allow scoping diffs by line range of a file and named
" block in a file. Inspired by reading the following article.
" https://susanpotter.net/software/tracking-diffs-by-scoping-to-file-range-function-method-or-class-changes-in-git/

" Use these two links as reference to come up with this function
" https://vi.stackexchange.com/questions/17606/vmap-and-visual-block-how-do-i-write-a-function-to-operate-once-for-the-entire
" https://stackoverflow.com/questions/41238238/how-to-map-vim-visual-mode-to-replace-my-selected-text-parts
function! git#git_log_range() abort
  let [lnum1, col1] = getpos("'<")[1:2]
  let [lnum2, col2] = getpos("'>")[1:2]
  silent execute "Git log --no-patch -L " . lnum1 . "," . lnum2 . ":%"
endfunction

" Taken from https://learnvimscriptthehardway.stevelosh.com/chapters/33.html.
" Modified and stripped to do what I needed.
function! git#git_log_named_block() abort
  normal! `<v`>y
  silent execute "Git log --no-patch -L :" . trim(shellescape(@@)) . ":%"
endfunction

" Compares current branch against master. For eg. git log master..current.
" This combined with Git difftool -y are helpful for MR reviews.
function! git#git_log_compare() abort
  let default = split(trim(system('git symbolic-ref refs/remotes/origin/HEAD')), '/')
  let current = trim(system('git branch --show-current'))
  let are_we_on_default = match(default[3], current)
  if (are_we_on_default == 0)
    echom "We are already on default branch. Nothing to compare."
  else
    silent execute "Git log " . default[3] . ".." . current
  endif
endfunction

" Merge remote origin:master/main into local:master/main
function! git#git_fetch_origin_merge() abort
  let default = split(trim(system('git symbolic-ref refs/remotes/origin/HEAD')), '/')
  execute "Git fetch origin " . default[3] . ":" . default[3]
endfunction

" Figures out whether default branch is main or master and runs git merge.
function! git#git_merge_origin() abort
  let default = split(trim(system('git symbolic-ref refs/remotes/origin/HEAD')), '/')
  let current = trim(system("git branch --show-current"))
  let are_we_on_default = match(default[3], current)
  if (are_we_on_default == 0)
    echom "Merging origin/" . default[3]
    execute "Git merge origin/" . default[3]
  else
    echom "Not on " . default[3]
  endif
endfunction

" Rebase the current checked out branch to the branch on the current line.
" Git branch -a should be run before this.
function! git#git_rebase_branch() abort
  let line = trim(getline('.'))
  let branch = split(line, "/")
  if len(branch) == 1
    " Handles the case for local branch
    execute "Git rebase " . branch[0]
  else
    " Handles the case for remote remotes/remote_name/branch_name
    let remote = branch[1]
    let branch = branch[2]
    execute "Git rebase " . remote . "/" . branch
  endif
  silent execute "bw"
endfunction

" Git reflog should be run first before invoking this
function! git#git_reflog_restore() abort
  let line = trim(getline('.'))
  " A line in git reflog is of the form below
  " f6a8c7ed4 HEAD@{73}: rebase (pick): gst-rtmp: Add mux queues to stats gathering
  let sl1 = split(line, ":")
  " sl1[0] will give f6a8c7ed4 HEAD@{73} for above example
  let sl2 = split(sl1[0], " ")
  " sl2[0] will have f6a8c7ed4 and sl2[1] will have HEAD@{73}
  echom "Command executed will be: Git reset --hard " . sl2[1]
  call inputsave()
  let restore = input('Restore to: ' . line . '. Enter y to proceed: ')
  call inputrestore()
  let to_restore = match(restore, 'y')
  if (to_restore == 0)
    execute "Git reset --hard " . sl2[1]
  else
    echom "Not restoring to " . line
  endif
endfunction

" Figures out whether default branch is main or master and runs git rebase.
function! git#git_rebase_origin() abort
  let default = split(trim(system('git symbolic-ref refs/remotes/origin/HEAD')), '/')
  echom "Rebasing current branch on origin/" . default[3]
  execute "Git rebase origin/" . default[3]
endfunction