// Headless test for civilization Step 5 (conflict, war & shifting borders). No display needed.
//
//   g++ -std=c++17 -O2 -Isrc/sim test_conflict.cpp src/sim/IcoSphere.cpp src/sim/Planet.cpp
//       src/sim/PlanetTectonics.cpp src/sim/PlanetDrift.cpp src/sim/PlanetErosion.cpp
//       src/sim/PlanetHydrology.cpp src/sim/PlanetBiomes.cpp src/sim/PlanetClimate.cpp
//       src/sim/PlanetLive.cpp src/sim/PlanetOcean.cpp src/sim/PlanetWeather.cpp
//       src/sim/PlanetVolcano.cpp src/sim/PlanetBiota.cpp src/sim/PlanetFloraGen.cpp
//       src/sim/PlanetFaunaGen.cpp src/sim/PlanetFungiGen.cpp src/sim/NameGen.cpp
//       src/sim/PlanetGeography.cpp src/sim/PlanetEcoregions.cpp src/sim/PlanetCiv.cpp
//       src/sim/PlanetNation.cpp src/sim/PlanetCulture.cpp src/sim/PlanetConflict.cpp
//       src/sim/PlanetIO.cpp -o /tmp/twar && /tmp/twar
//
// Verifies: wars start between neighbouring realms; conquest sets allegiance so computeTerritory moves
// the border (the city joins the overlord's realm); revolts clear allegiance; determinism + RNG
// isolation; save-v21 + step-back snapshot round-trip.

#include "Planet.hpp"
#include <cstdio>
#include <cmath>
#include <algorithm>
#include <sstream>

static int failures = 0;
static void check(bool cond, const char* what) {
    std::printf("  [%s] %s\n", cond ? "PASS" : "FAIL", what);
    if (!cond) ++failures;
}
static void settle(Planet& p, int maxSteps = 800) {
    int run = 0;
    for (int s = 0; s < maxSteps; ++s) { double mc = p.step(); if (mc < 2.0) { if (++run >= 3) break; } else run = 0; }
    p.computeClimate(); p.classifyBiomes();
}
static void drift(Planet& p, int iters) {
    p.drifting = true;
    for (int k = 0; k < iters; ++k) { double dt = p.cflDtMy(); p.advect(dt); p.step(); p.erode(dt); if (k >= iters/2) p.hydrology(dt*0.2); }
    p.computeClimate(); p.classifyBiomes();
}
// Crank the war knobs so conquest is frequent + persistent (isolates the mechanics from randomness).
static void aggressiveWars(Planet& p) {
    p.cfg.warDeclareRate = 8.0; p.cfg.warAmbition = 2.0; p.cfg.warIdeology = 2.0; p.cfg.warBorder = 2.0;
    p.cfg.warConquerScore = 0.05; p.cfg.warSackChance = 0.0; p.cfg.warExhaustion = 900.0;
    p.cfg.warRevoltRate = 0.0; p.cfg.warMinRealmPop = 1.0; p.cfg.warMaxConcurrent = 50; p.cfg.warCasualtyRate = 0.0;
}
static bool warsEqual(const std::vector<War>& a, const std::vector<War>& b) {
    if (a.size() != b.size()) return false;
    for (size_t i = 0; i < a.size(); ++i)
        if (a[i].attacker != b[i].attacker || a[i].defender != b[i].defender || a[i].battles != b[i].battles
            || std::fabs(a[i].warscore - b[i].warscore) > 1e-12) return false;
    return true;
}

int main() {
    PlanetConfig cfg; cfg.subdivisions = 5; cfg.seed = 4242;
    Planet p; p.generate(cfg); settle(p); drift(p, 400);
    const int n = (int)p.cells.size();
    const double yearH = p.cfg.dayLengthHours * p.cfg.yearLengthDays;
    p.placeSettlements();
    double lt = 0.0; for (int yr = 0; yr < 600; ++yr) { lt += 2.0 * yearH; p.stepCivilization(2.0 * yearH, lt); }
    aggressiveWars(p);

    std::printf("Conflict: wars erupt + conquest sets allegiance\n");
    bool sawWar = false; int totalDeclared = 0;
    for (long yr = 0; yr < 300; ++yr) {
        p.computeTerritory(); p.computeCultures();
        ConflictUpdate u = p.stepConflict(yr);
        if (!p.warList().empty()) sawWar = true;
        for (const WarEvent& e : u.events) if (e.title.find("declares war") != std::string::npos) ++totalDeclared;
    }
    p.computeTerritory();   // reflect the final allegiances
    int allegianceSet = 0;
    for (int a : p.settleAllegiance()) if (a >= 0) ++allegianceSet;
    std::printf("    saw wars: %s ; declared over run: %d ; cities under foreign rule: %d\n",
                sawWar ? "yes" : "no", totalDeclared, allegianceSet);
    check(sawWar, "wars break out between neighbouring realms");
    check(allegianceSet > 0, "at least one city is conquered (allegiance set)");

    std::printf("Conflict: conquest moves the border (city joins its overlord's realm)\n");
    {
        int joined = 0, crossedCulture = 0, checkedValidOverlord = 0;
        for (size_t s = 0; s < p.settlements.size(); ++s) {
            int ov = p.settleAllegiance()[s];
            if (ov < 0) continue;
            // Is the overlord still a living capital of some nation?
            int ovNation = -1;
            for (size_t ni = 0; ni < p.nationList().size(); ++ni) if (p.nationList()[ni].capital == ov) ovNation = (int)ni;
            if (ovNation < 0) continue;
            ++checkedValidOverlord;
            int myNation = p.settleNation()[s];
            if (myNation == ovNation && p.cellNation()[p.settlements[s].cell] == ovNation) ++joined;
            if (myNation == ovNation && s < p.settleCulture().size() &&
                p.settleCulture()[s] != p.settleCulture()[ov]) ++crossedCulture;
        }
        std::printf("    %d conquered cities have a living overlord ; %d joined it ; %d crossed a culture line\n",
                    checkedValidOverlord, joined, crossedCulture);
        check(checkedValidOverlord == 0 || joined > 0, "a conquered city sits in its overlord's realm (border moved)");
    }

    std::printf("Conflict: revolts free conquered cities\n");
    {
        int before = 0; for (int a : p.settleAllegiance()) if (a >= 0) ++before;
        p.cfg.warRevoltRate = 5.0; p.cfg.warDeclareRate = 0.0;   // no new wars, heavy revolts
        for (long yr = 300; yr < 320; ++yr) { p.computeTerritory(); p.computeCultures(); p.stepConflict(yr); }
        int after = 0; for (int a : p.settleAllegiance()) if (a >= 0) ++after;
        std::printf("    conquered cities before revolts: %d ; after: %d\n", before, after);
        check(before == 0 || after < before, "revolts reduce the number of conquered cities");
    }

    std::printf("Conflict: determinism\n");
    Planet q; q.generate(cfg); settle(q); drift(q, 400); q.placeSettlements();
    double lt2 = 0.0; for (int yr = 0; yr < 600; ++yr) { lt2 += 2.0 * yearH; q.stepCivilization(2.0 * yearH, lt2); }
    aggressiveWars(q);
    for (long yr = 0; yr < 300; ++yr) { q.computeTerritory(); q.computeCultures(); q.stepConflict(yr); }
    q.computeTerritory();
    // Re-run p's identical sequence into a third world to compare against (p has since had revolts applied).
    Planet p2; p2.generate(cfg); settle(p2); drift(p2, 400); p2.placeSettlements();
    double lt3 = 0.0; for (int yr = 0; yr < 600; ++yr) { lt3 += 2.0 * yearH; p2.stepCivilization(2.0 * yearH, lt3); }
    aggressiveWars(p2);
    for (long yr = 0; yr < 300; ++yr) { p2.computeTerritory(); p2.computeCultures(); p2.stepConflict(yr); }
    p2.computeTerritory();
    check(q.settleAllegiance() == p2.settleAllegiance() && warsEqual(q.warList(), p2.warList()),
          "stepConflict is deterministic (same allegiance + wars)");

    std::printf("Conflict: RNG isolation from tectonics\n");
    Planet x; x.generate(cfg); settle(x);
    Planet y; y.generate(cfg); settle(y);
    for (int k = 0; k < 40; ++k) {
        double dx = x.cflDtMy(); x.advect(dx); x.step(); x.erode(dx);
        double dy = y.cflDtMy(); y.advect(dy); y.step(); y.erode(dy);
        if (k == 20) { y.placeSettlements(); y.stepCivilization(yearH, yearH); y.computeTerritory(); y.computeCultures(); aggressiveWars(y); y.stepConflict(0); }
    }
    {
        bool same = true;
        for (int i = 0; i < n; ++i) if (std::fabs(x.cells[i].elevation - y.cells[i].elevation) > 1e-9) same = false;
        check(same, "stepConflict never perturbs tectonic evolution");
    }

    std::printf("Conflict: save v21 round-trip\n");
    {
        std::stringstream ss(std::ios::in | std::ios::out | std::ios::binary);
        p2.writeState(ss);
        Planet r;
        bool ok = r.readState(ss, true, true, true, true, true, true, true, true, true, true, true, true);
        check(ok, "readState accepts the v21 stream");
        check(r.settleAllegiance() == p2.settleAllegiance(), "allegiance survives save/load");
        check(warsEqual(r.warList(), p2.warList()), "active wars survive save/load");
        r.computeTerritory();
        check(r.cellNation() == p2.cellNation(), "territory recomputed after load matches (allegiance honoured)");
    }
    {
        Planet bad = p2;
        bad.wars.clear();
        War w; w.attacker = 0; w.defender = (int)bad.settlements.size() + 10;
        bad.wars.push_back(w);
        std::stringstream ss(std::ios::in | std::ios::out | std::ios::binary);
        bad.writeState(ss);
        Planet r;
        check(!r.readState(ss, true, true, true, true, true, true, true, true, true, true, true, true),
              "readState rejects active wars with invalid settlement endpoints");
    }
    if (p2.settlements.size() >= 2) {
        Planet bad = p2;
        bad.wars.clear();
        War a; a.attacker = 0; a.defender = 1;
        War b; b.attacker = 1; b.defender = 0;
        bad.wars.push_back(a);
        bad.wars.push_back(b);
        std::stringstream ss(std::ios::in | std::ios::out | std::ios::binary);
        bad.writeState(ss);
        Planet r;
        check(!r.readState(ss, true, true, true, true, true, true, true, true, true, true, true, true),
              "readState rejects duplicate active wars for the same realm pair");
    }

    std::printf("Conflict: step-back snapshot round-trip\n");
    {
        WeatherSnapshot snap = p2.captureWeather();
        std::vector<int> before = p2.settleAllegiance();
        std::vector<War> wbefore = p2.warList();
        // Mutate: heavy revolts + more wars.
        p2.cfg.warRevoltRate = 5.0; p2.cfg.warDeclareRate = 5.0;
        for (long yr = 400; yr < 410; ++yr) { p2.computeTerritory(); p2.computeCultures(); p2.stepConflict(yr); }
        bool changed = (p2.settleAllegiance() != before) || !warsEqual(p2.warList(), wbefore);
        p2.restoreWeather(snap);
        check(changed, "the mutation actually changed conflict state");
        check(p2.settleAllegiance() == before && warsEqual(p2.warList(), wbefore),
              "restoreWeather rewinds allegiance + wars (step-back)");
    }

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