reasampler/src/main.cpp

// main.cpp — the SINGLE translation unit that OWNS the REAPER API pointers.
//
// This file is the entire contract between REAPER and the extension:
//   * At startup REAPER scans UserPlugins/ for reaper_*.dll|dylib|so and
//     dlopen()s each one, then looks up ONE exported symbol: ReaperPluginEntry
//     (that name is produced by the REAPER_PLUGIN_ENTRYPOINT macro).
//   * REAPER calls it, handing over `rec` — a small dispatch struct.
//       - rec->GetFunc(name)      resolves any REAPER API function to a pointer
//       - rec->Register(what,ptr) plugs OUR callbacks into REAPER
//   * REAPERAPI_LoadAPI(rec->GetFunc) walks reaper_plugin_functions.h and
//     fills in every global function pointer (ShowConsoleMsg, InsertMedia...).
//
// Exactly ONE .cpp defines REAPERAPI_IMPLEMENT (this one) — that allocates
// storage for those global pointers. Every other .cpp includes
// reaper_plugin_functions.h WITHOUT the define and gets `extern` declarations.

#define REAPERAPI_IMPLEMENT
#include "reaper_plugin.h"
#include "reaper_plugin_functions.h"

#include <string>

#include "bank_model.h"
#include "bank_panel.h"
#include "capture.h"
#include "persist.h"

// Persistent action-id prefix for the ReaSampler action family.
// Every bindable action (capture / insert / slot / verify) mints its command id
// from a string beginning with this prefix, e.g. "CEREBELLUM_REASAMPLER_CAPTURE_MASTER".
// FOREVER-STABLE once shipped: user keybindings key off these strings, so the
// prefix and any minted id must never change after release.
#define REASAMPLER_ACTION_PREFIX "CEREBELLUM_REASAMPLER_"

// Globals other files reference via `extern`.
REAPER_PLUGIN_HINSTANCE g_hInst = nullptr;  // this module's instance handle
reaper_plugin_info_t*   g_rec   = nullptr;  // REAPER's dispatch struct

// ---- Action registration seam (M3 spike: capture master mix) ---------------
// First live use of the action pattern the seam left templated. The full capture
// action family (selected tracks/items/razor, wet/dry, tail) is M7; this is ONE
// temporary action driving the M3 offline-render spike.

// Command id for "ReaSampler: capture master mix (spike)". FOREVER-STABLE string
// (user keybindings key off it) — see the prefix note above.
static int g_cmdCaptureMasterSpike = 0;

// Command id for "ReaSampler: toggle bank panel" (M5). FOREVER-STABLE string.
// The docked grid window is display-only this wave (Wave A) — the action just
// shows/hides it; it never captures, inserts, or mutates the bank.
static int g_cmdToggleBankPanel = 0;

// The persistence session (M4): owns the in-memory BankIndex and bridges it to
// project ext state. A timer tick drives g_session.poll() to detect project
// load / Save-As; capture adds Samples to g_session.bank(); after a capture we
// serialize the bank back into the active project's ext state so it travels with
// the .rpp. Replaces the M3 session-only g_bank.
static reasampler::ReaSamplerSession g_session;

// The timer callback REAPER runs periodically (registered via "timer"). It only
// forwards to the session poll — cheap per tick (reads the active project id and
// its .rpp path, acts only on a change).
static void OnTimer()
{
    g_session.poll();
    // Reflect a live bank change (capture / project load) in the docked grid.
    // Cheap when the bank is unchanged (a fingerprint compare); repaints only on
    // an actual change. No-op when the panel is closed.
    reasampler::bankPanelRefresh();
}

// Runs the M3 spike: render the time-selection master mix, add the Sample, log.
static void RunCaptureMasterSpike()
{
    // Time selection -> exact render bounds (no rounding). GetSet_LoopTimeRange
    // with isSet=false reads the current time selection (isLoop=false).
    double start = 0.0, end = 0.0;
    GetSet_LoopTimeRange(false, false, &start, &end, false);

    reasampler::CaptureRequest req;
    req.sourceMode   = reasampler::SourceMode::TimeSelection;
    req.startSeconds = start;
    req.endSeconds   = end;
    req.wetDry       = 1.0;                              // wet master mix
    req.renderTail   = false;                            // exact bounds, no tail
    req.sampleRate   = 0;                                // follow project rate
    req.channelCount = 2;
    req.bitDepth     = reasampler::WavBitDepth::Float32; // deterministic, no dither
    req.baseName     = "master_mix";

    reasampler::OfflineRenderBackend backend;
    reasampler::CaptureResult res = backend.capture(req);

    if (res.status != reasampler::CaptureStatus::Ok)
    {
        ShowConsoleMsg(("ReaSampler capture failed: " + res.message + "\n").c_str());
        return;
    }

    reasampler::AddResult added = g_session.bank().add(res.sample);
    // Persist the updated bank into the active project's ext state so the capture
    // survives Save / close+reopen (M4). Non-destructive: writes only our own
    // ext-state key. No-ops on an unsaved project (nothing to store into yet).
    g_session.saveToActiveProject();

    std::string log = "ReaSampler: " + res.message + "\n";
    log += "  bank size now " + std::to_string(g_session.bank().size()) +
           (added == reasampler::AddResult::Added      ? " (added)\n"
            : added == reasampler::AddResult::Collapsed ? " (collapsed on hash)\n"
                                                        : " (rejected)\n");
    ShowConsoleMsg(log.c_str());
}

// REAPER calls this for EVERY action fired anywhere; claim only our own id,
// return false otherwise so REAPER keeps looking.
static bool OnHookCommand(int command, int /*flag*/)
{
    if (command == 0) return false;
    if (command == g_cmdCaptureMasterSpike) { RunCaptureMasterSpike(); return true; }
    if (command == g_cmdToggleBankPanel)    { reasampler::bankPanelToggle(); return true; }
    return false;
}

// REAPER polls this to render each of OUR actions' checked state in menus/toolbars.
// Return 1 (on) / 0 (off) for ids we own, -1 for everything else (per the contract).
static int OnToggleAction(int command)
{
    if (command == g_cmdToggleBankPanel)
        return reasampler::bankPanelIsOpen() ? 1 : 0;
    return -1;  // not ours / non-toggling
}

// gaccel storage must outlive registration — REAPER holds the pointer.
static gaccel_register_t g_accelCaptureMaster{};
static gaccel_register_t g_accelToggleBankPanel{};

extern "C" REAPER_PLUGIN_DLL_EXPORT int REAPER_PLUGIN_ENTRYPOINT(
    REAPER_PLUGIN_HINSTANCE hInstance, reaper_plugin_info_t* rec)
{
    if (!rec)
    {
        // rec == nullptr  =>  REAPER is UNLOADING us. Mirror-unregister every
        // callback with the same strings prefixed '-' (per the contract).
        if (g_rec)
        {
            g_rec->Register("-timer", (void*)&OnTimer);
            g_rec->Register("-toggleaction", (void*)&OnToggleAction);
            g_rec->Register("-hookcommand", (void*)&OnHookCommand);
            g_rec->Register("-gaccel", (void*)&g_accelToggleBankPanel);
            g_rec->Register("-command_id",
                            (void*)(REASAMPLER_ACTION_PREFIX "TOGGLE_BANK_PANEL"));
            g_rec->Register("-gaccel", (void*)&g_accelCaptureMaster);
            g_rec->Register("-command_id",
                            (void*)(REASAMPLER_ACTION_PREFIX "CAPTURE_MASTER_SPIKE"));
        }
        // Destroy the docked window and release cached thumbnails before we drop
        // the API pointers (DockWindowRemove/DestroyWindow need them live).
        reasampler::bankPanelShutdown();
        g_rec = nullptr;
        return 0;
    }

    // ABI guard: the struct layout we compiled against must match this REAPER.
    if (rec->caller_version != REAPER_PLUGIN_VERSION)
        return 0;

    // Resolve every REAPER API function pointer. Returns the number that FAILED
    // to load; 0 == success. Non-zero usually means REAPER is older than our SDK.
    if (REAPERAPI_LoadAPI(rec->GetFunc) != 0)
        return 0;

    g_hInst = hInstance;
    g_rec   = rec;

    // Register the M3 spike action (command_id -> gaccel -> hookcommand).
    g_cmdCaptureMasterSpike = rec->Register(
        "command_id",
        (void*)(REASAMPLER_ACTION_PREFIX "CAPTURE_MASTER_SPIKE"));
    if (g_cmdCaptureMasterSpike)
    {
        g_accelCaptureMaster.accel.cmd = g_cmdCaptureMasterSpike;
        g_accelCaptureMaster.desc      = "ReaSampler: capture master mix (spike)";
        rec->Register("gaccel", (void*)&g_accelCaptureMaster);
    }

    // Point the bank panel at the live session BEFORE registering its action, so
    // a toggle firing immediately has a session to read (M5). Does not open the
    // window — only stores the session pointer.
    reasampler::bankPanelInit(&g_session);

    // Register the M5 "toggle bank panel" action (command_id -> gaccel ->
    // hookcommand + toggleaction for the checked state).
    g_cmdToggleBankPanel = rec->Register(
        "command_id",
        (void*)(REASAMPLER_ACTION_PREFIX "TOGGLE_BANK_PANEL"));
    if (g_cmdToggleBankPanel)
    {
        g_accelToggleBankPanel.accel.cmd = g_cmdToggleBankPanel;
        g_accelToggleBankPanel.desc      = "ReaSampler: toggle bank panel";
        rec->Register("gaccel", (void*)&g_accelToggleBankPanel);
        rec->Register("toggleaction", (void*)&OnToggleAction);
    }

    // One hookcommand routes every ReaSampler action (spike + toggle). Registered
    // once, after both command ids are minted.
    rec->Register("hookcommand", (void*)&OnHookCommand);

    // Drive project-load / Save-As detection (M4 persist). The timer polls the
    // active project each tick; on a project load it reloads the bank from ext
    // state, on a Save-As it relocates the bank folder under the new .rpp.
    rec->Register("timer", (void*)&OnTimer);

    ShowConsoleMsg("ReaSampler loaded.\n");

    return 1;  // success — REAPER keeps us loaded
}