// Headless checks for the v25 viewer colour-mode/overlay save block (no window needed).
// Modeled on test_events.cpp.

#include "Viewer.hpp"
#include <cstdio>
#include <fstream>
#include <string>

static int failures = 0;
static void check(bool cond, const char* what) {
    std::printf("  [%s] %s\n", cond ? "PASS" : "FAIL", what);
    if (!cond) ++failures;
}

int main() {
    std::printf("Viewer state: v25 colour-mode/overlay save/load round-trip\n");
    Viewer v;
    PlanetConfig cfg; cfg.subdivisions = 2; cfg.seed = 777;
    v.cfg = cfg;
    v.planet.generate(cfg);

    // Set every overlay to a value that differs from the Viewer's own defaults, plus a non-default
    // colour mode, so a bug that left fields untouched (rather than round-tripped) would show up.
    v.mode = ColorMode::Biome;
    v.showBorders = false;      // default true
    v.showDrift = false;        // default true
    v.showRivers = false;       // default true
    v.showGrat = true;          // default false
    v.dayNightOn = false;       // default true
    v.showTides = true;         // default false
    v.showCurrents = true;      // default false
    v.showClouds = false;       // default true
    v.showVolcanoes = false;    // default true
    v.showNames = true;         // default false
    v.showSettlements = false;  // default true
    v.showDiplomacy = false;    // default true
    v.showRealms = true;        // default false

    const char* path = "/tmp/fanworgen_viewerstate_test.save";
    v.saveGame(path);

    Viewer r;
    r.loadGame(path);
    check(r.mode == ColorMode::Biome, "v25 save/load restores the colour mode");
    check(r.showBorders == false, "v25 restores showBorders");
    check(r.showDrift == false, "v25 restores showDrift");
    check(r.showRivers == false, "v25 restores showRivers");
    check(r.showGrat == true, "v25 restores showGrat");
    check(r.dayNightOn == false, "v25 restores dayNightOn");
    check(r.showTides == true, "v25 restores showTides");
    check(r.showCurrents == true, "v25 restores showCurrents");
    check(r.showClouds == false, "v25 restores showClouds");
    check(r.showVolcanoes == false, "v25 restores showVolcanoes");
    check(r.showNames == true, "v25 restores showNames");
    check(r.showSettlements == false, "v25 restores showSettlements");
    check(r.showDiplomacy == false, "v25 restores showDiplomacy");
    check(r.showRealms == true, "v25 restores showRealms");
    check(r.screen == AppScreen::World, "loadGame() switches the app screen to World");
    check(r.menuState.worldEverGenerated, "loadGame() marks a world as having been generated");

    // Negative test: patch the save's version back to 24 (pre-v25, no mode/overlay block) and load
    // into a fresh Viewer whose defaults differ from the saved-but-truncated values above -- must
    // not crash, and must leave mode/overlays exactly at the fresh Viewer's own pre-load values.
    {
        std::fstream fs(path, std::ios::in | std::ios::out | std::ios::binary);
        uint32_t oldVer = 24;
        fs.seekp(4);
        fs.write((char*)&oldVer, 4);
    }
    Viewer old;
    ColorMode preLoadMode = old.mode;
    bool preLoadBorders = old.showBorders, preLoadRealms = old.showRealms;
    old.loadGame(path);
    check(old.mode == preLoadMode, "pre-v25 saves leave the colour mode at its pre-load value");
    check(old.showBorders == preLoadBorders, "pre-v25 saves leave showBorders at its pre-load value");
    check(old.showRealms == preLoadRealms, "pre-v25 saves leave showRealms at its pre-load value");

    std::printf(failures ? "\nFAILURES: %d\n" : "\nALL VIEWER STATE CHECKS PASSED\n", failures);
    return failures ? 1 : 0;
}