Refactor hunk functionality.

autoload/hunk.vim

@@ -1,5 +1,14 @@
 " number of lines [added, modified, removed]
 let s:summary = [0, 0, 0]
+let s:hunks = []
+
+function! hunk#set_hunks(hunks)
+  let s:hunks = a:hunks
+endfunction
+
+function! hunk#hunks()
+  return s:hunks
+endfunction
 
 function! hunk#summary()
   return s:summary
@@ -21,4 +30,53 @@ function! hunk#increment_lines_removed(count)
   let s:summary[2] += a:count
 endfunction
 
+function! hunk#next_hunk(count)
+  if utility#is_active()
+    let current_line = line('.')
+    let hunk_count = 0
+    for hunk in s:hunks
+      if hunk[2] > current_line
+        let hunk_count += 1
+        if hunk_count == a:count
+          execute 'normal!' hunk[2] . 'G'
+          break
+        endif
+      endif
+    endfor
+  endif
+endfunction
+
+function! hunk#prev_hunk(count)
+  if utility#is_active()
+    let current_line = line('.')
+    let hunk_count = 0
+    for hunk in reverse(copy(s:hunks))
+      if hunk[2] < current_line
+        let hunk_count += 1
+        if hunk_count == a:count
+          execute 'normal!' hunk[2] . 'G'
+          break
+        endif
+      endif
+    endfor
+  endif
+endfunction
+
+" Returns the hunk the cursor is currently in or 0 if the cursor isn't in a
+" hunk.
+function! hunk#current_hunk()
+  let current_hunk = []
+  let current_line = line('.')
+
+  for hunk in s:hunks
+    if current_line >= hunk[2] && current_line < hunk[2] + (hunk[3] == 0 ? 1 : hunk[3])
+      let current_hunk = hunk
+      break
+    endif
+  endfor
+
+  if len(current_hunk) == 4
+    return current_hunk
+  endif
+endfunction