import 'dart:developer';
import 'dart:math' as math;

import 'package:dartterm/world/level.dart';

part 'direction.dart';
part 'direction_set.dart';
part 'orientation.dart';
part 'requirement.dart';
part 'vault.dart';
part 'vaults.dart';

class Generator {
  final math.Random _random;
  final Vaults _vaults;

  Generator(this._random, this._vaults);

  Vault generateBoxed(Requirement req) {
    var vx = req.vx;
    var vy = req.vy;

    var v = Vault.blank(vx, vy, req.smooth, LevelTile.wall);

    if (req.vx < 2 || req.vy < 2) {
      return v;
    }
    var req2 = Requirement(vx - 2, vy - 2, req.smooth);
    var inner = generate(req2);
    v.blitFrom(inner, 1, 1);
    return v;
  }

  Vault generate(Requirement requirement) {
    // TODO: Pick a relevant vault from the vaults file if possible

    // First of all: randomize orientation
    // This way we only have to consider one kind of spilt
    var orientation = randomOrientation(_random);

    // Try to make vx the long axis if possible
    var req2 = unReorientRequirement(requirement, orientation);
    if (req2.vy > (req2.vx - 2) * 3 / 2) {
      orientation = (orientation + 2) % 8; // rotate once more
    }
    req2 = unReorientRequirement(requirement, orientation);

    var out2 = _generate(req2);
    var out1 = reorientVault(out2, orientation);

    log("$orientation ${requirement.vx} ${requirement.vy} ${req2.vx} ${req2.vy} ${out2.vx} ${out2.vy} ${out1.vx} ${out1.vy}");
    assert(out1.vx == requirement.vx);
    assert(out1.vy == requirement.vy);
    return out1;
  }

  Vault _generate(Requirement req) {
    var vx = req.vx;
    var vy = req.vy;
    var v = Vault.blank(vx, vy, req.smooth, LevelTile.wall);

    if (vx < 5 || vx * vy < 10) {
      v.clear(LevelTile.floor);
    } else {
      // pick a split point
      var splitVx = _random.nextInt(vx - 4) + 2;

      var reqLeft = Requirement(splitVx, vy, req.smooth.clone());
      reqLeft.smooth.directions.add(Direction.right);
      var reqRight = Requirement((vx - splitVx - 1), vy, req.smooth.clone());
      reqRight.smooth.directions.add(Direction.left);

      var vaultLeft = generate(reqLeft);
      var vaultRight = generate(reqRight);
      v.blitFrom(vaultLeft, 0, 0);
      v.blitFrom(vaultRight, splitVx + 1, 0);
    }

    return v;
  }
}