import ViE.App
import ViE.Checkpoint
import ViE.State.Config
import Test.Utils

namespace Test.Checkpoint

open Test.Utils
open ViE

def testLoadSessionInvalid : IO Unit := do
  IO.println "Starting Checkpoint Parse Invalid Test..."
  IO.FS.writeFile ViE.Checkpoint.sessionFile "--ACTIVE--\nnot-a-number\n"
  let loaded <- ViE.Checkpoint.loadSession
  assertEqual "Invalid checkpoint parses as none" none loaded

def testLoadSessionValid : IO Unit := do
  IO.println "Starting Checkpoint Parse Valid Test..."
  let content :=
    "/tmp/file-a.txt\n" ++
    "0 0\n" ++
    "/tmp/file-b.txt\n" ++
    "3 4\n" ++
    "--ACTIVE--\n" ++
    "1\n"
  IO.FS.writeFile ViE.Checkpoint.sessionFile content
  let loaded <- ViE.Checkpoint.loadSession
  let expected : Option (List String × Nat × List (Nat × Nat)) :=
    some (["/tmp/file-a.txt", "/tmp/file-b.txt"], 1, [(0, 0), (3, 4)])
  assertEqual "Valid checkpoint parsing" expected loaded

def testBuildRestoredWorkspace : IO Unit := do
  IO.println "Starting Restored Workspace Build Test..."
  let stamp <- IO.monoMsNow
  let root := s!"/tmp/vie-checkpoint-{stamp}"
  IO.FS.createDirAll root

  let f1 := s!"{root}/a.txt"
  let f2 := s!"{root}/b.txt"
  IO.FS.writeFile f1 "alpha\nbeta\n"
  IO.FS.writeFile f2 "line0\nline1\nline2\n"

  let ws <- ViE.buildRestoredWorkspace ViE.defaultConfig (some root) [f1, f2] 1 [(0, 0), (1, 2)]

  assertEqual "Restored workspace buffer count" 2 ws.buffers.length
  assertEqual "Restored workspace nextBufferId" 2 ws.nextBufferId
  let active := ws.layout.findView ws.activeWindowId |>.getD ViE.initialView
  assertEqual "Restored active buffer id" 1 active.bufferId
  assertEqual "Restored cursor row" 1 active.cursor.row.val
  assertEqual "Restored cursor col" 2 active.cursor.col.val

  match ws.buffers with
  | b1 :: b2 :: _ =>
      assertEqual "Restored first file path" (some f1) b1.filename
      assertEqual "Restored second file path" (some f2) b2.filename
  | _ =>
      throw (IO.userError "Expected two restored buffers")

def testBuildRestoredWorkspaceCustomTabStop : IO Unit := do
  IO.println "Starting Restored Workspace Custom TabStop Test..."
  let stamp <- IO.monoMsNow
  let root := s!"/tmp/vie-checkpoint-tab-{stamp}"
  IO.FS.createDirAll root

  let f1 := s!"{root}/tab.txt"
  IO.FS.writeFile f1 "\talpha\n"
  let settings := { ViE.defaultConfig with tabStop := 8 }

  let ws <- ViE.buildRestoredWorkspace settings (some root) [f1] 0 [(0, 8)]
  let active := ws.layout.findView ws.activeWindowId |>.getD ViE.initialView
  assertEqual "Restored custom tabStop cursor row" 0 active.cursor.row.val
  assertEqual "Restored custom tabStop cursor col" 8 active.cursor.col.val

def test : IO Unit := do
  testLoadSessionInvalid
  testLoadSessionValid
  testBuildRestoredWorkspace
  testBuildRestoredWorkspaceCustomTabStop

end Test.Checkpoint