local process=require("process")
local unicode=require("unicode")
local event=require("event")
local event_mt=getmetatable(event.handlers)



local data={}
local widths={}
local sorted={}
local moved_indexes={}

local elbow=unicode.char(0x2514)

local function thread_id(t,p)
if t then
return tostring(t):gsub("^thread: 0x","")
end

for k,v in pairs(process.list)do
if v==p then
return thread_id(k)
end
end
return"-"
end

local cols=
{
{"PID",thread_id},
{"EVENTS",function(_,p)
local handlers={}
if event_mt.threaded then
handlers=rawget(p.data,"handlers")or{}
elseif not p.parent then
handlers=event.handlers
end
local count=0
for _ in pairs(handlers)do
count=count+1
end
return count==0 and"-"or tostring(count)
end},
{"THREADS",function(_,p)

local count=0
for _,h in ipairs(p.data.handles)do
local mt=getmetatable(h)
if mt and mt.__status then
count=count+1
end
end
return count==0 and"-"or tostring(count)
end},
{"PARENT",function(_,p)
for _,process_info in pairs(process.list)do
for i,handle in ipairs(process_info.data.handles)do
local mt=getmetatable(handle)
if mt and mt.__status then
if mt.process==p then
return thread_id(nil,process_info)
end
end
end
end
return thread_id(nil,p.parent)
end},
{"HANDLES",function(_,p)
local count=#p.data.handles
return count==0 and"-"or tostring(count)
end},
{"CMD",function(_,p)return p.command end},
}

local function add_field(key,value)
if not data[key]then data[key]={}end
table.insert(data[key],value)
widths[key]=math.max(widths[key]or 0,#value)
end

for _,key in ipairs(cols)do
add_field(key[1],key[1])
end

for thread_handle,process_info in pairs(process.list)do
for _,key in ipairs(cols)do
add_field(key[1],key[2](thread_handle,process_info))
end
end

local parent_index
for index,set in ipairs(cols)do
if set[1]=="PARENT"then
parent_index=index
break
end
end
assert(parent_index,"did not find a parent column")

local function move_to_sorted(index)
if moved_indexes[index]then
return false
end
local entry={}
for k,v in pairs(data)do
entry[k]=v[index]
end
sorted[#sorted+1]=entry
moved_indexes[index]=true
return true
end

local function make_elbow(depth)
return(" "):rep(depth-1)..(depth>0 and elbow or"")
end


move_to_sorted(1)

local function update_family(parent,depth)
depth=depth or 0
parent=parent or"-"
for index in ipairs(data.PID)do
local this_parent=data[cols[parent_index][1]][index]
if this_parent==parent then
local dash_cmd=make_elbow(depth)..data.CMD[index]
data.CMD[index]=dash_cmd
widths.CMD=math.max(widths.CMD or 0,#dash_cmd)
if move_to_sorted(index)then
update_family(data.PID[index],depth+1)
end
end
end
end

update_family()
table.remove(cols,parent_index)

for _,set in ipairs(sorted)do
local split=""
for _,key in ipairs(cols)do
local label=key[1]
local format=split.."%-"..tostring(widths[label]).."s"
io.write(string.format(format,set[label]))
split="   "
end
print()
end