local Y=require("yaru.core")
local gfx=require("yaru.gfx")
local ui=require("yaru.ui")
local computer=require("computer")
local component=require("component")
local fs=require("filesystem")
local unicode=require("unicode")

local M={}
local TABS={{"proc","Processes"},{"res","Resources"},{"fs","File Systems"},{"comp","Devices"}}
local BARS={" ","▁","▂","▃","▄","▅","▆","▇","█"}

local function graph(x,y,w,h,hist,maxv,fg,bg)
gfx.fill(x,y,w,h,bg)
local n=#hist
for i=1,math.min(w,n)do
local v=hist[n-i+1]/maxv
local cells=v*h
local col=x+w-i
for r=0,h-1 do
local fillAmt=cells-r
if fillAmt>=1 then gfx.cell(col,y+h-1-r,"█",fg,bg)
elseif fillAmt>0 then gfx.cell(col,y+h-1-r,BARS[1+math.floor(fillAmt*8)],fg,bg)end
end
end
end

local function processes()
local process=require("process")
local r={}
for co,p in pairs(process.list)do
local tid=tostring(co):gsub("^thread: 0x","")
local isThread=false
for _,q in pairs(process.list)do
for _,h in ipairs(q.data.handles or{})do
local mt=getmetatable(h)
if mt and mt.process==p then isThread=true end
end
end
local data=p.data
local term=rawget(data,"yaruTerm")
r[#r+1]={id=tid:sub(-6),cmd=p.command or tostring(p.path),thread=isThread,term=term,
status=coroutine.status(co),handles=#(data.handles or{})}
end
table.sort(r,function(a,b)return a.cmd<b.cmd end)
return r
end

function M.open()
local st={tab="res",mem={},energy={},top=0}
local win=Y.newWindow{app="monitor",title="System Monitor",w=86,h=26,minW=60,minH=14}
local function sample()
local tot,free=computer.totalMemory(),computer.freeMemory()
st.mem[#st.mem+1]=tot-free
st.energy[#st.energy+1]=computer.energy()
if#st.mem>120 then table.remove(st.mem,1);table.remove(st.energy,1)end
end
sample()
win.tickInterval=2
function win.tick(w)sample();Y.redraw(w)end

function win.header(w,hw)
local x=3
for _,tb in ipairs(TABS)do
local sel=st.tab==tb[1]
x=x+ui.button(w,x,1,tb[2],function()st.tab=tb[1];st.top=0 end,sel and nil or"flat")+1
end
end

function win.draw(w,cw,ch)
local t=Y.theme
gfx.fill(1,1,cw,ch,t.view)
if st.tab=="res"then
local tot,free=computer.totalMemory(),computer.freeMemory()
local used=tot-free
gfx.text(2,1,"Memory",t.fg,t.view)
local ms=string.format("%s used of %s (%d%%)",ui.size(used),ui.size(tot),used*100//tot)
gfx.text(cw-1-unicode.len(ms),1,ms,t.dim,t.view)
local gh=math.max(3,(ch-8)//2)
ui.graph(2,2,cw-3,gh,st.mem,tot,t.accent)
local y=3+gh
local me=computer.maxEnergy()
gfx.text(2,y,"Energy",t.fg,t.view)
local es=me>0 and string.format("%.0f of %.0f (%d%%)",computer.energy(),me,computer.energy()*100//me)or"n/a"
gfx.text(cw-1-unicode.len(es),y,es,t.dim,t.view)
ui.graph(2,y+1,cw-3,gh,st.energy,math.max(1,me),t.success)
y=y+gh+2
local gs=gfx.stats
gfx.text(2,y,string.format("Desktop: last frame %.1f ms, %d GPU runs  •  total GPU set %d fill %d copy %d, colour changes %d",
Y.stats.lastFrameMs or 0,Y.stats.lastRuns or 0,gs.set,gs.fill,gs.copy,gs.fg+gs.bg),t.dim,t.view)
gfx.text(2,y+1,string.format("Uptime %d:%02d:%02d  •  windows %d  •  loaded app modules: %s",math.floor(computer.uptime()//3600),
math.floor(computer.uptime()//60%60),math.floor(computer.uptime()%60),#Y.windows,(function()
local l={}for k in pairs(Y.modules)do l[#l+1]=k end return table.concat(l,", ")end)()),t.dim,t.view)
elseif st.tab=="proc"then
local list=processes()
gfx.fill(1,1,cw,1,t.sidebar)
gfx.text(2,1,"ID",t.dim,t.sidebar);gfx.text(10,1,"Command",t.dim,t.sidebar)
gfx.text(cw-28,1,"Type",t.dim,t.sidebar);gfx.text(cw-16,1,"State",t.dim,t.sidebar)
for i=1,ch-1 do
local p=list[st.top+i]
if not p then break end
local y=i+1
gfx.text(2,y,p.id,t.dim,t.view)
gfx.text(10,y,ui.trunc(p.cmd,cw-40),t.fg,t.view)
gfx.text(cw-28,y,p.term and("terminal "..p.term)or(p.thread and"thread"or"process"),t.dim,t.view)
gfx.text(cw-16,y,p.status,p.status=="running"and t.success or t.dim,t.view)
end
ui.scrollbar(cw,2,ch-1,st.top,ch-1,#list)
elseif st.tab=="fs"then
local y=1
local seen={}
for proxy,path in fs.mounts()do
if not seen[proxy.address]and y+2<=ch then
seen[proxy.address]=true
local total,used=proxy.spaceTotal(),proxy.spaceUsed()
local label=proxy.getLabel()or proxy.address:sub(1,8)
gfx.text(2,y,ui.trunc(path.."  "..label..(proxy.isReadOnly()and"  (read-only)"or""),cw-30),t.fg,t.view)
local s=total==math.huge and ui.size(used).." used"or string.format("%s of %s",ui.size(used),ui.size(total))
gfx.text(cw-1-unicode.len(s),y,s,t.dim,t.view)
gfx.fill(2,y+1,cw-3,1,t.sep)
if total>0 and total~=math.huge then gfx.fill(2,y+1,math.max(1,math.floor((cw-3)*used/total)),1,t.accent)end
y=y+3
end
end
else
local list={}
for addr,typ in component.list()do list[#list+1]={typ,addr}end
table.sort(list,function(a,b)return a[1]<b[1]end)
for i=1,ch do
local c=list[st.top+i]
if not c then break end
gfx.text(2,i,ui.pad(c[1],20),t.fg,t.view)
gfx.text(24,i,c[2],t.dim,t.view)
local primary=component.isAvailable(c[1])and component.getPrimary(c[1]).address==c[2]
if primary then gfx.text(cw-10,i,"primary",t.accent,t.view)end
end
ui.scrollbar(cw,1,ch,st.top,ch,#list)
end
end
function win.scroll(w,x,y,dir)st.top=math.max(0,st.top-dir*3)end
function win.key(w,char,code)
local K=Y.K
if code==K.down then st.top=st.top+1 elseif code==K.up then st.top=math.max(0,st.top-1)
elseif code==K.tab or code==K.right then
for i,tb in ipairs(TABS)do if tb[1]==st.tab then st.tab=TABS[i%#TABS+1][1];break end end
st.top=0
end
end
return win
end

return M