/// <reference path="BaseAction.ts"/>

module TK.SpaceTac {
    /**
     * Action to trigger an equipment (for example a weapon), with an optional target
     * 
     * The target will be resolved as a list of ships, on which all the action effects will be applied
     */
    export class TriggerAction extends BaseAction {
        // Power consumption
        power: number

        // Maximal range of the weapon (distance to target)
        range: number

        // Radius around the target that will be impacted
        blast: number

        // Angle of the area between the source and the target that will be impacted
        angle: number

        // Influence of "precision" of firing ship (0..100)
        aim: number

        // Influence of "maneuvrability" of impacted ship (0..100)
        evasion: number

        // Influence of luck
        luck: number

        // Effects applied on target
        effects: BaseEffect[]

        // Equipment cannot be null
        equipment: Equipment

        constructor(equipment: Equipment, effects: BaseEffect[] = [], power = 1, range = 0, blast = 0, angle = 0, aim = 0, evasion = 0, luck = 0, code = `fire-${equipment.code}`) {
            super(code, equipment);

            this.power = power;
            this.range = range;
            this.effects = effects;
            this.blast = blast;
            this.angle = angle;
            this.aim = aim;
            this.evasion = evasion;
            this.luck = luck;
        }

        getVerb(): string {
            return this.range ? "Fire" : "Trigger";
        }

        getDefaultTarget(ship: Ship): Target {
            if (this.range == 0) {
                return Target.newFromShip(ship);
            } else {
                let battle = ship.getBattle();
                if (battle) {
                    let harmful = any(this.effects, effect => !effect.isBeneficial());
                    let player = ship.getPlayer();
                    let ships = imaterialize(harmful ? battle.ienemies(player, true) : ifilter(battle.iallies(player, true), iship => iship != ship));
                    let nearest = minBy(ships, iship => arenaDistance(ship.location, iship.location));
                    return Target.newFromShip(nearest);
                } else {
                    return Target.newFromShip(ship);
                }
            }
        }

        getTargettingMode(ship: Ship): ActionTargettingMode {
            if (this.blast) {
                if (this.range) {
                    return ActionTargettingMode.SPACE;
                } else {
                    return ActionTargettingMode.SURROUNDINGS;
                }
            } else if (this.range) {
                if (this.angle) {
                    return ActionTargettingMode.SPACE;
                } else {
                    return ActionTargettingMode.SHIP;
                }
            } else {
                return ActionTargettingMode.SELF_CONFIRM;
            }
        }

        getActionPointsUsage(ship: Ship, target: Target | null): number {
            return this.power;
        }

        getRangeRadius(ship: Ship): number {
            return this.range;
        }

        /**
         * Get the success factor [0-1] for this action applied from a ship to another
         * 
         * This is a predictible formula, not including random elements.
         */
        getSuccessFactor(from: Ship, to: Ship): number {
            let aim = this.aim * 0.01;
            let evasion = this.evasion * 0.01;
            let f1 = (x: number) => (x < 0 ? -1 : 1) * (1 - 1 / (x * x + 1));
            let prec = from.getAttribute("precision");
            let man = to.getAttribute("maneuvrability");
            let delta = Math.min(aim, evasion) * f1(0.2 * (prec - man));
            return clamp(1 - aim * (1 - f1(prec)) - evasion * f1(man) + delta, 0, 1);
        }

        /**
         * Get the effective success of the action [0-1].
         * 
         * Result has more chance to be near the success factor, but may be in the whole [0-1] range.
         */
        getEffectiveSuccess(from: Ship, to: Ship, random = RandomGenerator.global): number {
            let p = this.getSuccessFactor(from, to);
            let s = this.luck * 0.01;
            if (s) {
                let c = (2 / (2 - s)) - 1;
                let x = random.random();
                if (x <= p) {
                    return Math.pow(x, c) / Math.pow(p, c - 1);
                } else {
                    return 1 - Math.pow(1 - x, c) / Math.pow(1 - p, c - 1);
                }
            } else {
                return p;
            }
        }

        filterImpactedShips(source: ArenaLocation, target: Target, ships: Ship[]): Ship[] {
            if (this.blast) {
                return ships.filter(ship => arenaDistance(ship.location, target) <= this.blast);
            } else if (this.angle) {
                let angle = arenaAngle(source, target);
                let maxangle = (this.angle * 0.5) * Math.PI / 180;
                return ships.filter(ship => {
                    let dist = arenaDistance(source, ship.location);
                    if (dist < 0.000001 || dist > this.range) {
                        return false;
                    } else {
                        return Math.abs(angularDistance(arenaAngle(source, ship.location), angle)) < maxangle;
                    }
                });
            } else {
                return ships.filter(ship => ship.is(target.ship_id));
            }
        }

        checkLocationTarget(ship: Ship, target: Target): Target | null {
            if (target && (this.blast > 0 || this.angle > 0)) {
                target = target.constraintInRange(ship.arena_x, ship.arena_y, this.range);
                return target;
            } else {
                return null;
            }
        }

        checkShipTarget(ship: Ship, target: Target): Target | null {
            if (this.range > 0 && ship.is(target.ship_id)) {
                // No self fire
                return null;
            } else {
                // Check if target is in range
                if (this.blast > 0 || this.angle > 0) {
                    return this.checkLocationTarget(ship, new Target(target.x, target.y));
                } else if (target.isInRange(ship.arena_x, ship.arena_y, this.range)) {
                    return target;
                } else {
                    return null;
                }
            }
        }

        /**
         * Collect the effects applied by this action
         * 
         * If *luck* is specified, an effective success factor is used, instead of an estimated one
         */
        getEffects(ship: Ship, target: Target, source = ship.location, luck?: RandomGenerator): [Ship, BaseEffect, number][] {
            let result: [Ship, BaseEffect, number][] = [];
            let ships = this.getImpactedShips(ship, target, source);
            ships.forEach(iship => {
                let success = luck ? this.getEffectiveSuccess(ship, iship, luck) : this.getSuccessFactor(ship, iship);
                this.effects.forEach(effect => result.push([iship, effect, success]));
            });
            return result;
        }

        protected getSpecificDiffs(ship: Ship, battle: Battle, target: Target): BaseBattleDiff[] {
            let result: BaseBattleDiff[] = [];

            if (arenaDistance(ship.location, target) > 1e-6) {
                // Face the target
                let angle = arenaAngle(ship.location, target);
                if (Math.abs(angularDistance(angle, ship.arena_angle)) > 1e-6) {
                    let destination = new ArenaLocationAngle(ship.arena_x, ship.arena_y, angle);
                    let engine = first(ship.listEquipment(SlotType.Engine), () => true);
                    result.push(new ShipMoveDiff(ship, ship.location, destination, engine));
                }

                // Fire a projectile
                if (this.equipment && this.equipment.slot_type == SlotType.Weapon) {
                    result.push(new ProjectileFiredDiff(ship, this.equipment, target));
                }
            }

            // Apply effects
            let effects = this.getEffects(ship, target, undefined, RandomGenerator.global);
            effects.forEach(([ship_target, effect, success]) => {
                let diffs = effect.getOnDiffs(ship_target, ship, success);
                result = result.concat(diffs);
            });

            return result;
        }

        getEffectsDescription(): string {
            if (this.effects.length == 0) {
                return "";
            }

            let info: string[] = [];
            if (this.power) {
                info.push(`power ${this.power}`);
            }
            if (this.range) {
                info.push(`range ${this.range}km`);
            }
            if (this.aim) {
                info.push(`aim +${this.aim}%`);
            }
            if (this.evasion) {
                info.push(`evasion -${this.evasion}%`);
            }
            if (this.luck) {
                info.push(`luck ±${this.luck}%`);
            }

            let desc = (info.length) ? `${this.getVerb()} (${info.join(", ")})` : this.getVerb();
            let effects = this.effects.map(effect => {
                let suffix: string;
                if (this.blast) {
                    suffix = `in ${this.blast}km radius`;
                } else if (this.angle) {
                    suffix = `in ${this.angle}° arc`;
                } else if (this.range) {
                    suffix = "on target";
                } else {
                    suffix = "on self";
                }
                return "• " + effect.getDescription() + " " + suffix;
            });
            return `${desc}:\n${effects.join("\n")}`;
        }
    }
}