-- Stub just enough of the reaper API to exercise the pure logic in the lib.
local ext = { root = "0", scale = "1" }
reaper = {
  GetExtState = function(_, k) return ext[k] or "" end,
  SetExtState = function(_, k, v) ext[k] = v end,
  APIExists = function() return false end,
  ShowConsoleMsg = function() end,
  SNM_GetIntConfigVar = function(_, d) return 1 end,
  GetCursorPosition = function() return 0 end,
  TimeMap_GetTimeSigAtTime = function() return 4, 4 end,
}

local G = dofile("D:\\code\\midigrid\\midigrid_lib.lua")

local fails = 0
local function eq(got, want, label)
  if got ~= want then
    print(("FAIL %s: got %s want %s"):format(label, tostring(got), tostring(want)))
    fails = fails + 1
  end
end

-- Note naming: with midioctoffs=1, note 60 reads as C5 (Reaper's default).
eq(G.noteName(60), "C5", "noteName 60")
eq(G.noteName(61), "C#5", "noteName 61")
eq(G.noteName(72), "C6", "noteName 72")
eq(G.noteName(48), "C4", "noteName 48")

-- C major: stepping up from C5 walks the scale, not semitones.
ext.root, ext.scale = "0", "1"
local p, seq = 60, {}
for _ = 1, 7 do p = G.scaleStep(p, 1); seq[#seq + 1] = p end
eq(table.concat(seq, ","), "62,64,65,67,69,71,72", "C major ascending")

p, seq = 60, {}
for _ = 1, 3 do p = G.scaleStep(p, -1); seq[#seq + 1] = p end
eq(table.concat(seq, ","), "59,57,55", "C major descending")

-- An off-scale note must not trap the cursor: C#5 in C major steps to D5.
eq(G.scaleStep(61, 1), 62, "off-scale up")
eq(G.scaleStep(61, -1), 60, "off-scale down")

-- Pentatonic skips more than a tone.
ext.scale = "10" -- major pentatonic
eq(G.scaleStep(60, 1), 62, "pentatonic C->D")
eq(G.scaleStep(64, 1), 67, "pentatonic E->G")

-- Chromatic behaves like plain semitones.
ext.scale = "14"
eq(G.scaleStep(60, 1), 61, "chromatic up")

-- Root transposition: A natural minor.
ext.root, ext.scale = "9", "2"
eq(G.inScale(69), true, "A in A minor")
eq(G.inScale(70), false, "A# not in A minor")
eq(G.scaleName(), "A natural minor", "scale name")

-- Range clamping at the extremes of the MIDI range.
ext.root, ext.scale = "0", "1"
eq(G.scaleStep(127, 1), nil, "top of range")
eq(G.scaleStep(0, -1), nil, "bottom of range")

-- Grid labels in 4/4: one bar is 4 QN.
eq(G.gridLabel(4), "1 bar", "grid 1 bar")
eq(G.gridLabel(8), "2 bars", "grid 2 bars")
eq(G.gridLabel(1), "1/4", "grid quarter")
eq(G.gridLabel(0.25), "1/16", "grid sixteenth")
eq(G.gridLabel(0.5), "1/8", "grid eighth")

print(fails == 0 and "ALL PASS" or (fails .. " FAILURES"))