local core = require "core"

---@class runner
local runner = {
  new = function(self, o)
    o = o or {}
    setmetatable(o, self)
    self.__index = self
    return o
  end,

  caps = {
    can_pause = false,
    can_continue = false,
    can_step_in = false,
    can_step_over = false,
    can_step_out = false,
    can_breakpoints = false,
    has_stack = false,
    has_locals = false,
    can_eval = false,
  },

  run = function(self, target, name) end,  ---@meta
  pause = function(self) end, --@meta
  continue = function(self) end, --@meta
  step_in = function(self) end, --@meta
  step_over = function(self) end, --@meta
  step_out = function(self) end, --@meta

  wait = function(self, time) end,  ---@meta 
  kill = function(self) end, ---@meta 
  terminate = function(self) end, ---@meta

  -- Callbacks
  log = function(msg) end, ---@meta
  error = function(msg) end, ---@meta
  on_stdout = function(msg) end, ---@meta
  on_stderr = function(msg) end, ---@meta
  on_exit = function(exitcode) end, ---@meta
  on_state = function(state) end, ---@meta
  on_break = function(file, line, reason) end, --@meta
  on_stack = function(frames) end, ---@meta
  on_locals = function(frame, vars) end, ---@meta
  on_evaluated = function(expr, ok, value) end, ---@meta
}

local debugger = {
  runner = runner, -- Set here as member to let runners extend this base class
  debugwindow = nil, ---@type JPDebugView
  debugrunner = nil, ---@type runner|nil
}

function debugger.log(msg)
  core.log("[jpdebug][debugger] %s", msg)
  if debugger.debugwindow then debugger.debugwindow:push("meta", "debugger] "..msg) end
end

function debugger.error(msg)
  core.error("[jpdebug][debugger]"..msg)
  if debugger.debugwindow then debugger.debugwindow:push("meta", "debugger] ERROR: "..msg) end
end

function debugger.on_stdout(msg)
  if debugger.debugwindow then debugger.debugwindow:push("stdout", msg) end
end

function debugger.on_stderr(msg)
  if debugger.debugwindow then debugger.debugwindow:push("stderr", msg) end
end

function debugger.is_running()
  return debugger.debugrunner~=nil
end

function debugger.run(target, name, r, view)
  if debugger.debugrunner then
    debugger.error("Already an active session")
    return
  end
  debugger.debugwindow = view
  debugger.debugwindow:clear()
  debugger.log(string.format("Running %s", name))

  -- Create new runner object
  debugger.debugrunner = r:new({
    -- Set callbacks
    log = debugger.log,
    error = debugger.error,
    on_stdout = debugger.on_stdout,
    on_stderr = debugger.on_stderr,
    on_exit = debugger.on_exit,
  })
  -- And run
  debugger.debugrunner:run(target, name)
end

function debugger.stop()
  if debugger.debugrunner then
    debugger.debugrunner.on_exit = function() end
    debugger.debugrunner:kill()
    local exitcode = debugger.debugrunner:wait(1000)
    -- TODO terminate if needed
    debugger.log(string.format("... Stoped with exit code %d", exitcode))
  end
  debugger.debugrunner = nil
end

function debugger.on_exit(exitcode)
  debugger.log(string.format("exit: %d", exitcode))
  debugger.debugrunner = nil
end

return debugger