/*
htop - ProcessList.c
(C) 2004,2005 Hisham H. Muhammad
Released under the GNU GPLv2, see the COPYING file
in the source distribution for its full text.
*/

#include "ProcessList.h"

#include <assert.h>
#include <string.h>
#include <time.h>

#include "CRT.h"
#include "XUtils.h"


ProcessList* ProcessList_init(ProcessList* this, const ObjectClass* klass, UsersTable* usersTable, Hashtable* pidMatchList, uid_t userId) {
   this->processes = Vector_new(klass, true, DEFAULT_SIZE);
   this->processTable = Hashtable_new(140, false);
   this->usersTable = usersTable;
   this->pidMatchList = pidMatchList;
   this->userId = userId;

   // tree-view auxiliary buffer
   this->processes2 = Vector_new(klass, true, DEFAULT_SIZE);

   // set later by platform-specific code
   this->cpuCount = 0;

   this->scanTs = 0;

#ifdef HAVE_LIBHWLOC
   this->topologyOk = false;
   if (hwloc_topology_init(&this->topology) == 0) {
      this->topologyOk =
         #if HWLOC_API_VERSION < 0x00020000
         /* try to ignore the top-level machine object type */
         0 == hwloc_topology_ignore_type_keep_structure(this->topology, HWLOC_OBJ_MACHINE) &&
         /* ignore caches, which don't add structure */
         0 == hwloc_topology_ignore_type_keep_structure(this->topology, HWLOC_OBJ_CORE) &&
         0 == hwloc_topology_ignore_type_keep_structure(this->topology, HWLOC_OBJ_CACHE) &&
         0 == hwloc_topology_set_flags(this->topology, HWLOC_TOPOLOGY_FLAG_WHOLE_SYSTEM) &&
         #else
         0 == hwloc_topology_set_all_types_filter(this->topology, HWLOC_TYPE_FILTER_KEEP_STRUCTURE) &&
         #endif
         0 == hwloc_topology_load(this->topology);
   }
#endif

   this->following = -1;

   return this;
}

void ProcessList_done(ProcessList* this) {
#ifdef HAVE_LIBHWLOC
   if (this->topologyOk) {
      hwloc_topology_destroy(this->topology);
   }
#endif
   Hashtable_delete(this->processTable);
   Vector_delete(this->processes);
   Vector_delete(this->processes2);
}

void ProcessList_setPanel(ProcessList* this, Panel* panel) {
   this->panel = panel;
}

void ProcessList_printHeader(ProcessList* this, RichString* header) {
   RichString_prune(header);
   const ProcessField* fields = this->settings->fields;
   for (int i = 0; fields[i]; i++) {
      const char* field = Process_fields[fields[i]].title;
      if (!field) {
         field = "- ";
      }

      int color = (!this->settings->treeView && this->settings->sortKey == fields[i]) ?
         CRT_colors[PANEL_SELECTION_FOCUS] : CRT_colors[PANEL_HEADER_FOCUS];
      RichString_append(header, color, field);
      if (COMM == fields[i] && this->settings->showMergedCommand) {
         RichString_append(header, color, "(merged)");
      }
   }
}

void ProcessList_add(ProcessList* this, Process* p) {
   assert(Vector_indexOf(this->processes, p, Process_pidCompare) == -1);
   assert(Hashtable_get(this->processTable, p->pid) == NULL);
   p->processList = this;

   // highlighting processes found in first scan by first scan marked "far in the past"
   p->seenTs = this->scanTs;

   Vector_add(this->processes, p);
   Hashtable_put(this->processTable, p->pid, p);

   assert(Vector_indexOf(this->processes, p, Process_pidCompare) != -1);
   assert(Hashtable_get(this->processTable, p->pid) != NULL);
   assert(Hashtable_count(this->processTable) == Vector_count(this->processes));
}

void ProcessList_remove(ProcessList* this, Process* p) {
   assert(Vector_indexOf(this->processes, p, Process_pidCompare) != -1);
   assert(Hashtable_get(this->processTable, p->pid) != NULL);

   Process* pp = Hashtable_remove(this->processTable, p->pid);
   assert(pp == p); (void)pp;

   unsigned int pid = p->pid;
   int idx = Vector_indexOf(this->processes, p, Process_pidCompare);
   assert(idx != -1);

   if (idx >= 0) {
      Vector_remove(this->processes, idx);
   }

   assert(Hashtable_get(this->processTable, pid) == NULL); (void)pid;
   assert(Hashtable_count(this->processTable) == Vector_count(this->processes));
}

Process* ProcessList_get(ProcessList* this, int idx) {
   return (Process*) (Vector_get(this->processes, idx));
}

int ProcessList_size(ProcessList* this) {
   return (Vector_size(this->processes));
}

static void ProcessList_buildTree(ProcessList* this, pid_t pid, int level, int indent, int direction, bool show) {
   Vector* children = Vector_new(Class(Process), false, DEFAULT_SIZE);

   for (int i = Vector_size(this->processes) - 1; i >= 0; i--) {
      Process* process = (Process*) (Vector_get(this->processes, i));
      if (process->show && Process_isChildOf(process, pid)) {
         process = (Process*) (Vector_take(this->processes, i));
         Vector_add(children, process);
      }
   }
   int size = Vector_size(children);
   for (int i = 0; i < size; i++) {
      Process* process = (Process*) (Vector_get(children, i));
      if (!show) {
         process->show = false;
      }

      int s = Vector_size(this->processes2);
      if (direction == 1) {
         Vector_add(this->processes2, process);
      } else {
         Vector_insert(this->processes2, 0, process);
      }

      assert(Vector_size(this->processes2) == s+1); (void)s;

      int nextIndent = indent | (1 << level);
      ProcessList_buildTree(this, process->pid, level+1, (i < size - 1) ? nextIndent : indent, direction, show ? process->showChildren : false);

      if (i == size - 1) {
         process->indent = -nextIndent;
      } else {
         process->indent = nextIndent;
      }
   }
   Vector_delete(children);
}

static long ProcessList_treeProcessCompare(const void* v1, const void* v2) {
   const Process *p1 = (const Process*)v1;
   const Process *p2 = (const Process*)v2;

   return p1->pid - p2->pid;
}

void ProcessList_sort(ProcessList* this) {
   if (!this->settings->treeView) {
      Vector_insertionSort(this->processes);
   } else {
      // Save settings
      int direction = this->settings->direction;
      // Sort by PID
      Vector_quickSortCustomCompare(this->processes, ProcessList_treeProcessCompare);
      int vsize = Vector_size(this->processes);
      // Find all processes whose parent is not visible
      int size;
      while ((size = Vector_size(this->processes))) {
         int i;
         for (i = 0; i < size; i++) {
            Process* process = (Process*)(Vector_get(this->processes, i));
            // Immediately consume not shown processes
            if (!process->show) {
               process = (Process*)(Vector_take(this->processes, i));
               process->indent = 0;
               Vector_add(this->processes2, process);
               ProcessList_buildTree(this, process->pid, 0, 0, direction, false);
               break;
            }
            pid_t ppid = Process_getParentPid(process);
            // Bisect the process vector to find parent
            int l = 0, r = size;
            // If PID corresponds with PPID (e.g. "kernel_task" (PID:0, PPID:0)
            // on Mac OS X 10.11.6) cancel bisecting and regard this process as
            // root.
            if (process->pid == ppid)
               r = 0;

            while (l < r) {
               int c = (l + r) / 2;
               pid_t pid = ((Process*)(Vector_get(this->processes, c)))->pid;
               if (ppid == pid) {
                  break;
               } else if (ppid < pid) {
                  r = c;
               } else {
                  l = c + 1;
               }
            }
            // If parent not found, then construct the tree with this root
            if (l >= r) {
               process = (Process*)(Vector_take(this->processes, i));
               process->indent = 0;
               Vector_add(this->processes2, process);
               ProcessList_buildTree(this, process->pid, 0, 0, direction, process->showChildren);
               break;
            }
         }
         // There should be no loop in the process tree
         assert(i < size);
      }
      assert(Vector_size(this->processes2) == vsize); (void)vsize;
      assert(Vector_size(this->processes) == 0);
      // Swap listings around
      Vector* t = this->processes;
      this->processes = this->processes2;
      this->processes2 = t;
   }
}


ProcessField ProcessList_keyAt(const ProcessList* this, int at) {
   int x = 0;
   const ProcessField* fields = this->settings->fields;
   ProcessField field;
   for (int i = 0; (field = fields[i]); i++) {
      const char* title = Process_fields[field].title;
      if (!title) {
         title = "- ";
      }

      int len = strlen(title);
      if (at >= x && at <= x + len) {
         return field;
      }
      x += len;
   }
   return COMM;
}

void ProcessList_expandTree(ProcessList* this) {
   int size = Vector_size(this->processes);
   for (int i = 0; i < size; i++) {
      Process* process = (Process*) Vector_get(this->processes, i);
      process->showChildren = true;
   }
}

void ProcessList_rebuildPanel(ProcessList* this) {
   const char* incFilter = this->incFilter;

   int currPos = Panel_getSelectedIndex(this->panel);
   pid_t currPid = this->following != -1 ? this->following : 0;
   int currScrollV = this->panel->scrollV;

   Panel_prune(this->panel);
   int size = ProcessList_size(this);
   int idx = 0;
   for (int i = 0; i < size; i++) {
      bool hidden = false;
      Process* p = ProcessList_get(this, i);

      if ( (!p->show)
         || (this->userId != (uid_t) -1 && (p->st_uid != this->userId))
         || (incFilter && !(String_contains_i(Process_getCommand(p), incFilter)))
         || (this->pidMatchList && !Hashtable_get(this->pidMatchList, p->tgid)) )
         hidden = true;

      if (!hidden) {
         Panel_set(this->panel, idx, (Object*)p);
         if ((this->following == -1 && idx == currPos) || (this->following != -1 && p->pid == currPid)) {
            Panel_setSelected(this->panel, idx);
            this->panel->scrollV = currScrollV;
         }
         idx++;
      }
   }
}

Process* ProcessList_getProcess(ProcessList* this, pid_t pid, bool* preExisting, Process_New constructor) {
   Process* proc = (Process*) Hashtable_get(this->processTable, pid);
   *preExisting = proc;
   if (proc) {
      assert(Vector_indexOf(this->processes, proc, Process_pidCompare) != -1);
      assert(proc->pid == pid);
   } else {
      proc = constructor(this->settings);
      assert(proc->comm == NULL);
      proc->pid = pid;
   }
   return proc;
}

void ProcessList_scan(ProcessList* this, bool pauseProcessUpdate) {
   struct timespec now;

   // in pause mode only gather global data for meters (CPU/memory/...)
   if (pauseProcessUpdate) {
      ProcessList_goThroughEntries(this, true);
      return;
   }

   // mark all process as "dirty"
   for (int i = 0; i < Vector_size(this->processes); i++) {
      Process* p = (Process*) Vector_get(this->processes, i);
      p->updated = false;
      p->wasShown = p->show;
      p->show = true;
   }

   this->totalTasks = 0;
   this->userlandThreads = 0;
   this->kernelThreads = 0;
   this->runningTasks = 0;


   // set scanTs
   static bool firstScanDone = false;
   if (!firstScanDone) {
      this->scanTs = 0;
      firstScanDone = true;
   } else if (clock_gettime(CLOCK_MONOTONIC, &now) == 0) {
      this->scanTs = now.tv_sec;
   }

   ProcessList_goThroughEntries(this, false);

   for (int i = Vector_size(this->processes) - 1; i >= 0; i--) {
      Process* p = (Process*) Vector_get(this->processes, i);
      if (p->tombTs > 0) {
         // remove tombed process
         if (this->scanTs >= p->tombTs) {
            ProcessList_remove(this, p);
         }
      } else if (p->updated == false) {
         // process no longer exists
         if (this->settings->highlightChanges && p->wasShown) {
            // mark tombed
            p->tombTs = this->scanTs + this->settings->highlightDelaySecs;
         } else {
            // immediately remove
            ProcessList_remove(this, p);
         }
      } else {
         p->updated = false;
      }
   }
}