if !has("python")
 echo "vim has to be compiled with +python to run this"
 finish
endif

if exists('g:loaded_stackview_plugin')
 finish
endif

" the rest of plugin VimL code goes here
let g:loaded_stackview_plugin = 1

let s:plugin_root_dir = fnamemodify(resolve(expand('<sfile>:p')), ':h')

python << EOF
import sys
from os.path import normpath, join
import vim
plugin_root_dir = vim.eval('s:plugin_root_dir')
python_root_dir = normpath(join(plugin_root_dir, '..', 'python'))
sys.path.insert(0, python_root_dir)
from gdbmi_utils import *
EOF

let StackView_title = "__StackView_List__"
let s:StackView_bufnum = 0
let StackViewTagNameFG ='#43beef'
let StackViewTagFocusFG ='#2e8b57'

"FUNCTION: s:bufInWindows(bnum)
"Determine the number of windows open to this buffer number.
"Care of Yegappan Lakshman. Thanks!
"
"Args:
"bnum: the subject buffers buffer number
function! s:bufInWindows(bnum)
 let cnt = 0
 let winnum = 1
 while 1
 let bufnum = winbufnr(winnum)
 if bufnum < 0
 break
 endif
 if bufnum == a:bnum
 let cnt = cnt + 1
 endif
 let winnum = winnum + 1
 endwhile

 return cnt
endfunction

"FUNCTION: s:isWindowUsable(winnumber)
"Returns 1 if opening a file from the tree in the given window requires it to
"be split
"
"Args:
"winnumber: the number of the window in question
function! s:isWindowUsable(winnumber)
 "gotta split if theres only one window (i.e. the NERD tree)
 if winnr("$") == 1
 return 0
 endif

 let oldwinnr = winnr()
 exec a:winnumber . "wincmd p"
 let specialWindow = getbufvar("%", '&buftype') != '' || getwinvar('%', '&previewwindow')
 let modified = &modified
 exec oldwinnr . "wincmd p"

 "if its a special window e.g. quickfix or another explorer plugin then we
 "have to split
 if specialWindow
 return 0
 endif

 if &hidden
 return 1
 endif

 return !modified || s:bufInWindows(winbufnr(a:winnumber)) >= 2
endfunction

"FUNCTION: s:firstNormalWindow()
"find the window number of the first normal window
function! s:firstNormalWindow()
 let i = 1
 while i <= winnr("$")
 let bnum = winbufnr(i)
 if bnum != -1 && getbufvar(bnum, '&buftype') == ''
 \ && !getwinvar(i, '&previewwindow')
 return i
 endif

 let i += 1
 endwhile
 return -1
endfunction

" StackView_Open_Window
" Create a new window. If it is already open, clear it
function! s:StackView_Open_Window()

 " Cleanup the window listing, if the window is open
 let winnum = bufwinnr(g:StackView_title)
 if winnum != -1
 " Jump to the existing window
 if winnr() != winnum
 exe winnum . 'wincmd w'
 endif
 else
 " If the tag listing temporary buffer already exists, then reuse it.
 " Otherwise create a new buffer
 let bufnum = bufnr(g:StackView_title)
 if bufnum == -1
 " Create a new buffer
 let wcmd = g:StackView_title
 else
 " Edit the existing buffer
 let wcmd = '+buffer' . bufnum
 endif

 let s:StackView_bufnum = bufnum

 " Create the window
 exe 'silent! ' . 'topleft vertical 30 new ' . wcmd

 endif
endfunction

" StackView_Cleanup()
" Cleanup all the window variables.
function! s:StackView_Cleanup()
 if has('syntax')
 silent! syntax clear StackViewTitle
 silent! syntax clear StackViewTagName
 silent! syntax clear StackViewTagFocus
 endif
 match none

 if exists('b:tlist_wp_count') && b:tlist_wp_count != ''
 let line_num = 0
 while line_num < b:tlist_wp_count
 let item_index = 0
 while item_index < b:tlist_fp_{line_num}_count
 unlet! b:tlist_fp_{line_num}_{item_index}_fullname
 unlet! b:tlist_fp_{line_num}_{item_index}_line
 let item_index = item_index + 1
 endwhile
 unlet! b:tlist_fp_{line_num}_list
 let line_num = line_num + 1
 endwhile
 endif

 unlet! b:tlist_wp_start
 unlet! b:tlist_wp_count
 unlet! b:tlist_wp_list
endfunction

" StackView_Init_Window
" Set the default options for the window
function! s:StackView_Init_Window(filename)
 " Set report option to a huge value to prevent informations messages
 " while deleting the lines
 let old_report = &report
 set report=99999

 " Mark the buffer as modifiable
 setlocal modifiable

 " Delete the contents of the buffer to the black-hole register
 silent! %delete _

 " Mark the buffer as not modifiable
 setlocal nomodifiable

 " Restore the report option
 let &report = old_report

 " Clean up all the old variables used for the last filetype
 call <SID>StackView_Cleanup()

 " Mark the buffer as modifiable
 setlocal modifiable

 call append(0, '" StackView')
 let txt = fnamemodify(a:filename, ':t') . ' (' .
 \ fnamemodify(a:filename, ':p:h') . ')'
 silent! put! =txt

 " Mark the buffer as not modifiable
 setlocal nomodifiable

 " Highlight the comments
 if has('syntax')
 syntax match StackViewComment '^" .*'
 syntax match StackViewFileName '^[^" ].*$'

 " Colors to highlight comments and titles
 highlight clear StackViewComment
 highlight link StackViewComment Comment
 highlight clear StackViewTitle
 highlight link StackViewTitle Title
 if hlexists('MyStackViewFileName')
 highlight link StackViewFileName MyStackViewFileName
 else
 highlight clear StackViewFileName
 highlight default StackViewFileName guibg=Grey ctermbg=darkgray
 \ guifg=white ctermfg=white
 endif
 endif

 " Folding related settings
 if has('folding')
 setlocal foldenable
 setlocal foldmethod=manual
 setlocal foldcolumn=2
 setlocal foldtext=v:folddashes.getline(v:foldstart)
 endif

 " Mark buffer as scratch
 silent! setlocal buftype=nofile
 silent! setlocal bufhidden=delete
 silent! setlocal noswapfile
 " Due to a bug in Vim 6.0, the winbufnr() function fails for unlisted
 " buffers. So if the list buffer is unlisted, multiple list
 " windows will be opened. This bug is fixed in Vim 6.1 and above
 if v:version >= 601
 silent! setlocal nobuflisted
 endif

 silent! setlocal nowrap

 " If the 'number' option is set in the source window, it will affect the
 " list window. So forcefully disable 'number' option for the list
 " window
 silent! setlocal nonumber

 silent! setlocal winfixwidth

 silent! setlocal nospell
 iabc <buffer>

 nnoremap <buffer> <silent> <2-LeftMouse> :call <SID>StackView_Jump_To_Tag(0)<CR>
endfunction

function! s:StackView_Window_Refresh(bkfile)
 " Mark the buffer as modifiable
 setlocal modifiable
 normal! ggdG
 " Mark the buffer as not modifiable
 setlocal nomodifiable

 " Initialize the list window
 call s:StackView_Init_Window(a:bkfile)

 " List the tags defined in a file
 call s:StackView_Explore_File(a:bkfile)
endfunction

" StackView_Explore_File()
" List the tags defined in the specified file in a Vim window
function! s:StackView_Explore_File(filename)
 let bufnum = s:StackView_bufnum

 let ftype = fnamemodify(a:filename, ':e')

 " Check for valid filename and valid filetype
 if a:filename == '' || !filereadable(a:filename) || ftype == ''
 return
 endif

 " Set report option to a huge value to prevent informational messages
 " while adding lines to the list window
 let old_report = &report
 set report=99999

 " Mark the buffer as modifiable
 setlocal modifiable

 if !exists('b:curr_wp_select')
 let b:curr_wp_select = 0
 endif

 call LoadConfig(a:filename)

 silent! put ='focus'
 let b:tlist_wp_start = line('.')
 silent! put = b:tlist_wp_list

 " create a fold for focus
 if has('folding')
 let fold_start = b:tlist_wp_start
 let fold_end = fold_start + b:tlist_wp_count
 exe fold_start . ',' . fold_end . 'fold'
 endif

 " Syntax highlight the focus names
 if has('syntax')
 exe 'syntax match StackViewTitle /\%' . b:tlist_wp_start . 'l.*/'
 silent! syntax clear StackViewTagFocus
 silent! exe 'highlight StackViewTagFocus term=bold ctermfg=Cyan guifg=' . g:StackViewTagFocusFG . ' gui=bold'
 let l:hl_line = b:tlist_wp_start + b:curr_wp_select + 1
 silent! exe 'syntax match StackViewTagFocus /\%' . l:hl_line . 'l.*/'
 endif

 silent! put =''

 let b:tlist_fp_start = line('.') + 1
 silent! put ='stack_list'
 silent! put = b:tlist_fp_{b:curr_wp_select}_list

 " create a fold for stack_list
 if has('folding')
 let fold_start = b:tlist_fp_start
 let fold_end = fold_start + b:tlist_fp_{b:curr_wp_select}_count
 exe fold_start . ',' . fold_end . 'fold'
 endif

 " Syntax highlight the stack_list names
 if has('syntax')
 exe 'syntax match StackViewTitle /\%' . b:tlist_fp_start . 'l.*/'
 endif

 normal! Gdd

 " Mark the buffer as not modifiable
 setlocal nomodifiable

 " Restore the report option
 let &report = old_report

 " Initially open all the folds
 if has('folding')
 silent! %foldopen!
 endif

 " Goto the first line in the buffer
 go

 return
endfunction

" StackView_Toggle_Window()
" Open a StackView window
function! s:StackView_Toggle_Window(bkfile)
 if a:bkfile == ""
 echo 'Please specify a file[*.bkpt] path!'
 return
 endif

 let curline = line('.')

 " If list window is open then close it.
 let winnum = bufwinnr(g:StackView_title)
 if winnum != -1
 if winnr() == winnum
 " Already in the list window. Close it and return
 close
 else
 " Goto the list window, close it and then come back to the
 " original window
 let curbufnr = bufnr('%')
 exe winnum . 'wincmd w'
 close
 " Need to jump back to the original window only if we are not
 " already in that window
 let winnum = bufwinnr(curbufnr)
 if winnr() != winnum
 exe winnum . 'wincmd w'
 endif
 endif
 return
 endif

 " Open the list window
 call s:StackView_Open_Window()

 " Initialize the list window
 call s:StackView_Init_Window(a:bkfile)

 " List the tags defined in a file
 call s:StackView_Explore_File(a:bkfile)
endfunction

" StackView_Jump_To_Tag()
" Jump to the location of the current tag
function! s:StackView_Jump_To_Tag(new_window)
 " Do not process comment lines and empty lines
 let curline = line('.') - 1

 if curline >= b:tlist_fp_start
 let l:tag_num = curline - b:tlist_fp_start
 let l:tag_fullname = b:tlist_fp_{b:curr_wp_select}_{l:tag_num}_fullname
 let l:tag_line = b:tlist_fp_{b:curr_wp_select}_{l:tag_num}_line

 silent! syntax clear StackViewTagName
 silent! exe 'highlight StackViewTagName term=bold ctermfg=Cyan guifg=' . g:StackViewTagNameFG . ' gui=bold'
 silent! exe 'syntax match StackViewTagName /\%' . line('.') . 'l.*/'

 if !s:isWindowUsable(winnr("#"))
 exec s:firstNormalWindow() . "wincmd w"
 else
 wincmd p
 endif

 exec ("edit " . l:tag_fullname)

 " Jump to the tag
 silent call cursor(l:tag_line, 0)
 elseif curline >= b:tlist_wp_start && curline < b:tlist_wp_start + b:tlist_wp_count
 let b:curr_wp_select = curline - b:tlist_wp_start
 call s:StackView_Window_Refresh(s:stackview_config_path)
 else
 return
 endif

endfunction

function! LoadConfig(filename)
 let s:stackview_config_path = a:filename
 python load_config()
endfunction

command! -n=? -complete=file StackView :call s:StackView_Toggle_Window('<args>')