(local json (require :json))
(local inspect (require :inspect))
(local l6502 (require :l6502-lua))

(fn slurp [path]
  (let [f (io.open path)]
    (f:read "*all")))

(fn must-match [fnm a e]
  (if (= a e) true
    (io.stderr:write (.. "\n -> in field " fnm ", expected " (tostring e) " but found " (tostring a) "\n"))
    (os.exit 1)))

(fn u8-flag? [v f] (not (= (band v f) 0)))

(fn run-test [e tc]
  (io.stderr:write (.. "running test: " tc.name "..."))
  (let [i tc.initial]
    (e:set-pc i.pc)
    (e:set-reg l6502.reg.SP i.s)
    (e:set-reg l6502.reg.A i.a)
    (e:set-reg l6502.reg.X i.x)
    (e:set-reg l6502.reg.Y i.y)
    (e:set-reg l6502.reg.FLAGS i.p)
    (each [_ [addr v] (ipairs i.ram)]
      (e:write addr v)))
  (e:emulate)
  (let [f tc.final]
    (must-match :pc (e:pc) f.pc)
    (must-match :sp (e:reg l6502.reg.SP) f.s)
    (must-match :a (e:reg l6502.reg.A) f.a)
    (must-match :x (e:reg l6502.reg.X) f.x)
    (must-match :y (e:reg l6502.reg.Y) f.y))
  (io.stderr:write " done\n")
  )

(fn run-tests-file [e p]
  (let [tcs (json.decode (slurp p))]
    (each [_ tc (ipairs tcs)]
      (run-test e tc))))

(let [e (l6502.new)]
  (for [i 0x00 0xff]
    (run-tests-file e (string.format "testcases/6502/v1/%02x.json" i))
    ))