-- Run with `lua _selfcheck.lua` or `panto lua _selfcheck.lua`; no live terminal writes.
local events, writes, env = {}, {}, {}
local handle, inode, pid = "tty", 10, 100.0
local write_error, partial_limit
os.getenv = function(name) return env[name] end
package.loaded.panto = nil
package.preload.panto = function()
   return { ext = { on = function(name, handler) events[name] = handler end } }
end
package.loaded.luv = nil
package.preload.luv = function()
   return {
      guess_handle = function(fd) assert(fd == 1); return handle end,
      fs_fstat = function(fd) assert(fd == 1); return { dev = 1, ino = inode, rdev = 2 } end,
      os_getpid = function() return pid end,
      os_setenv = function(name, value) env[name] = value end,
      fs_write = function(fd, data, offset)
         assert(fd == 1 and offset == -1)
         if write_error then return nil, "EIO" end
         local chunk = data:sub(1, partial_limit or #data)
         writes[#writes + 1] = chunk
         return #chunk
      end,
   }
end
local entry = assert(loadfile("panto-report-status/init.lua"))()
local function activate()
   events = {}
   entry.activate()
end
local function latest(state, message)
   local last
   for body in table.concat(writes):gmatch("\27%]7501;([^\27]*)\27\\") do last = body end
   assert(last, "missing report")
   assert(last == "state=" .. state .. ":app=panto" .. (message and ":msg=" .. message or ""), last)
end
local function unchanged(fn)
   local count = #writes
   fn()
   assert(#writes == count)
end

for _, kind in ipairs({ "pipe", "file", "unknown" }) do
   handle = kind
   activate()
   assert(next(events) == nil and #writes == 0)
end
handle = "tty"
activate()
assert(env.PANTO_REPORT_STATUS_OWNER == "1:10:2@100")
local registered = 0
for _ in pairs(events) do registered = registered + 1 end
assert(registered == 13)
events.session_ready()
latest("idle")
unchanged(events.session_ready)
unchanged(events.render_compaction)
unchanged(events.background_work_end)
unchanged(function() events.turn_end({ reason = "completed" }) end)

for _, name in ipairs({ "turn_start", "agent_submission", "render_thinking" }) do
   events[name]()
   latest("working", "dGhpbmtpbmc=") -- thinking
   unchanged(events[name])
   events.turn_end({ reason = "completed" })
   latest("done")
end
for _, item in ipairs({
   { "a", "dG9vbDph" }, { "ab", "dG9vbDphYg==" }, { "abc", "dG9vbDphYmM=" },
   { "a\27\n\t\127\194\128", "dG9vbDphPz8/Pz8/" },
}) do
   events.render_tool_details({ tool_name = item[1] })
   latest("working", item[2])
end
events.render_assistant_text()
latest("working", "cmVzcG9uZGluZw==") -- responding
events.render_compaction()
latest("working", "Y29tcGFjdGluZw==") -- compacting
events.turn_end({ reason = "completed" })
latest("done")
unchanged(events.render_compaction)

for _, item in ipairs({
   { "compact", "Y29tcGFjdGluZw==" }, { "!", "c2hlbGw=" },
   { "!!", "c2hlbGw=" }, { "status", "Y21kOnN0YXR1cw==" },
}) do
   events.command_start({ command_name = item[1] })
   latest("working", item[2])
   events.command_end({ command_name = item[1] })
   latest("done")
end

-- Foreground and background work must settle together, including failures.
events.turn_start()
events.background_work_start()
events.background_work_start()
events.turn_end({ reason = "failed" })
latest("working", "YmFja2dyb3VuZA==") -- background
unchanged(events.background_work_end)
events.background_work_end()
latest("error")
unchanged(events.background_work_end)
events.turn_start()
events.turn_end({ reason = "completed" })
latest("done")
for _, reason in ipairs({ "interrupted", "exit_requested" }) do
   events.turn_start()
   events.turn_end({ reason = reason })
   latest("idle")
end
events.background_work_start()
latest("working", "YmFja2dyb3VuZA==")
events.background_work_end()
latest("done")
events.background_work_start()
events.turn_start()
unchanged(events.background_work_end)
latest("working", "dGhpbmtpbmc=")
events.turn_end()
latest("done")

-- An output redirected after activation must remain clean.
handle = "pipe"
unchanged(events.turn_start)
handle = "tty"
events.turn_start()
latest("working", "dGhpbmtpbmc=")
-- A failed write must not mark the new state as successfully sent.
write_error = true
local ok, err = pcall(events.render_assistant_text)
assert(not ok and tostring(err):find("panto-report-status:", 1, true))
write_error = nil
events.render_assistant_text()
latest("working", "cmVzcG9uZGluZw==")
-- Synchronous writes may be short; finish the entire sequence in order.
partial_limit = 3
events.turn_end()
latest("done")
partial_limit = nil
events.session_end()
latest("clear")
unchanged(events.session_end)
unchanged(function() events.turn_start(); events.background_work_start(); events.background_work_end() end)

-- /new in the owning process reports; children in the same terminal do not.
activate()
events.session_ready()
latest("idle")
pid = 200.0
unchanged(activate)
assert(next(events) == nil)
-- A newly created terminal may report, even with an inherited owner marker.
inode = 20
activate()
assert(env.PANTO_REPORT_STATUS_OWNER == "1:20:2@200")
events.session_ready()
latest("idle")
-- Changing terminals after activation cannot redirect an existing reporter.
inode = 30
unchanged(events.turn_start)
print("panto-report-status self-check: ok")