#include "dialogue/DialogueRuntime.h"

#include <algorithm>
#include <iostream>

namespace ZL::Dialogue {

static std::pair<std::string, std::string> splitDot(const std::string& s) {
	const auto dot = s.find('.');
	if (dot == std::string::npos) return {s, ""};
	return {s.substr(0, dot), s.substr(dot + 1)};
}

void DialogueRuntime::setDatabase(const DialogueDatabase* value) {
	database = value;
}

bool DialogueRuntime::startDialogue(const std::string& dialogueId) {
	if (!database) {
		std::cerr << "[dialogue] No database assigned to runtime\n";
		return false;
	}

	if (mode != Mode::Inactive && activeDialogue && activeDialogue->uninterruptible) {
		std::cerr << "[dialogue] Blocked: '" << activeDialogue->id << "' is uninterruptible\n";
		return false;
	}

	const DialogueDefinition* dialogue = database->findDialogue(dialogueId);
	if (!dialogue) {
		std::cerr << "[dialogue] Dialogue not found: " << dialogueId << "\n";
		return false;
	}

	activeDialogue = dialogue;
	currentNodeId.clear();
	visibleChoices.clear();
	selectedChoice = -1;
	revealCharacters = 0.0f;
	presentation = {};
	presentation.dialogueId = dialogue->id;

	return enterNode(dialogue->startNode);
}

void DialogueRuntime::stop() {
	activeDialogue = nullptr;
	currentNodeId.clear();
	visibleChoices.clear();
	selectedChoice = -1;
	revealCharacters = 0.0f;
	mode = Mode::Inactive;
	presentation = {};
}

void DialogueRuntime::resumeFromNode(const std::string& nodeId) {
	if (mode != Mode::WaitingForCutscene) return;
	if (nodeId.empty()) {
		stop();
		return;
	}
	enterNode(nodeId);
}

void DialogueRuntime::setOnCutsceneStartNeeded(
	std::function<void(const std::string&, const std::string&)> cb)
{
	onCutsceneStartNeeded = std::move(cb);
}

void DialogueRuntime::setOnDialogueLineStarted(std::function<void(const std::string&)> cb) {
	onDialogueLineStarted = std::move(cb);
}

void DialogueRuntime::setOnChatBubbleReady(std::function<void(const std::string&, bool)> cb) {
	onChatBubbleReady = std::move(cb);
}

void DialogueRuntime::update(int deltaMs) {
	if (mode != Mode::PresentingLine) return;

	if (!presentation.revealCompleted) {
		revealCharacters += revealSpeedCharsPerSecond * (static_cast<float>(deltaMs) / 1000.0f);
		const size_t fullLen = presentation.fullText.size();
		const size_t visibleLen = static_cast<size_t>(std::min<float>(revealCharacters, static_cast<float>(fullLen)));
		presentation.visibleText = presentation.fullText.substr(0, visibleLen);
		presentation.revealCompleted = (visibleLen >= fullLen);
	}
}

void DialogueRuntime::confirmAdvance() {
	if (mode == Mode::PresentingLine) {
		if (!presentation.revealCompleted) {
			presentation.visibleText = presentation.fullText;
			presentation.revealCompleted = true;
			revealCharacters = static_cast<float>(presentation.fullText.size());
			return;
		}

		if (!activeDialogue) {
			stop();
			return;
		}

		auto it = activeDialogue->nodes.find(currentNodeId);
		if (it == activeDialogue->nodes.end()) {
			stop();
			return;
		}

		if (!it->second.next.empty()) {
			enterNode(it->second.next);
		}
		else {
			stop();
		}
		return;
	}

	if (mode == Mode::WaitingForChoice) {
		if (visibleChoices.empty() || selectedChoice < 0 || selectedChoice >= static_cast<int>(visibleChoices.size())) {
			return;
		}

		const Choice& choice = visibleChoices[selectedChoice];
		if (choice.consumeOnce && !choice.id.empty()) {
			consumedChoices.insert(choice.id);
		}
		applyEffects(choice.effects);
		enterNode(choice.next);
		return;
	}
}

void DialogueRuntime::moveSelection(int delta) {
	if (mode != Mode::WaitingForChoice || visibleChoices.empty()) return;

	const int count = static_cast<int>(visibleChoices.size());
	if (selectedChoice < 0 || selectedChoice >= count) {
		selectedChoice = (delta >= 0) ? 0 : (count - 1);
	}
	else {
		selectedChoice = (selectedChoice + delta) % count;
		if (selectedChoice < 0) selectedChoice += count;
	}
	presentation.selectedChoice = selectedChoice;
}

void DialogueRuntime::selectChoice(int index) {
	if (mode != Mode::WaitingForChoice || visibleChoices.empty()) return;
	if (index < 0 || index >= static_cast<int>(visibleChoices.size())) return;
	selectedChoice = index;
	presentation.selectedChoice = selectedChoice;
}

void DialogueRuntime::setFlag(const std::string& name, int value) {
	if (flagStore) (*flagStore)[name] = value;
}

int DialogueRuntime::getFlag(const std::string& name) const {
	if (!flagStore) return 0;
	auto it = flagStore->find(name);
	return (it != flagStore->end()) ? it->second : 0;
}

void DialogueRuntime::setGlobalFlagStore(std::unordered_map<std::string, int>* store) {
	flagStore = store;
}

void DialogueRuntime::setQuestJournal(Quest::QuestJournal* journal) {
	questJournal = journal;
}

void DialogueRuntime::applyQuestActions(
	const std::string& questUnlock, const std::string& questComplete,
	const std::string& questFail, const std::string& objectiveComplete,
	const std::string& objectiveVisible)
{
	if (!questJournal) return;
	if (!questUnlock.empty())       questJournal->unlockQuest(questUnlock);
	if (!questComplete.empty())     questJournal->completeQuest(questComplete);
	if (!questFail.empty())         questJournal->failQuest(questFail);
	if (!objectiveComplete.empty()) {
		auto [qId, oId] = splitDot(objectiveComplete);
		questJournal->setObjectiveCompleted(qId, oId);
	}
	if (!objectiveVisible.empty()) {
		auto [qId, oId] = splitDot(objectiveVisible);
		questJournal->setObjectiveVisible(qId, oId);
	}
}

bool DialogueRuntime::evaluateConditions(const std::vector<Condition>& conditions) const {
	for (const Condition& condition : conditions) {
		const int currentValue = getFlag(condition.flag);
		switch (condition.op) {
		case ComparisonOp::Exists:
			if (currentValue == 0) return false;
			break;
		case ComparisonOp::Equals:
			if (currentValue != condition.value) return false;
			break;
		case ComparisonOp::NotEquals:
			if (currentValue == condition.value) return false;
			break;
		case ComparisonOp::GreaterOrEqual:
			if (currentValue < condition.value) return false;
			break;
		case ComparisonOp::LessOrEqual:
			if (currentValue > condition.value) return false;
			break;
		}
	}
	return true;
}

void DialogueRuntime::applyEffects(const std::vector<Effect>& effects) {
	for (const Effect& effect : effects) {
		if (effect.flag.empty()) continue;
		if (effect.relative) {
			setFlag(effect.flag, getFlag(effect.flag) + effect.value);
		}
		else {
			setFlag(effect.flag, effect.value);
		}
	}
}

bool DialogueRuntime::enterNode(const std::string& nodeId) {
	if (!activeDialogue) {
		stop();
		return false;
	}

	auto it = activeDialogue->nodes.find(nodeId);
	if (it == activeDialogue->nodes.end()) {
		std::cerr << "[dialogue] Node not found: " << nodeId << " in dialogue " << activeDialogue->id << "\n";
		stop();
		return false;
	}

	const Node& node = it->second;
	currentNodeId = node.id;
	presentation.dialogueId = activeDialogue->id;

	switch (node.type) {
	case NodeType::Line:
		presentLine(node);
		return true;

	case NodeType::Choice:
		presentChoices(node);
		return true;

	case NodeType::Condition:
		if (evaluateConditions(node.conditions)) {
			return enterNode(!node.trueNext.empty() ? node.trueNext : node.next);
		}
		return enterNode(node.falseNext);

	case NodeType::SetFlag:
		applyEffects(node.effects);
		if (!node.next.empty()) {
			return enterNode(node.next);
		}
		stop();
		return true;

	case NodeType::Jump:
		if (!node.next.empty()) {
			return enterNode(node.next);
		}
		stop();
		return true;

	case NodeType::End:
		if (!node.luaCallback.empty() && onDialogueLineStarted)
			onDialogueLineStarted(node.luaCallback);
		stop();
		return true;

	case NodeType::CutsceneStart:
		// Pause dialogue and hand off to the cutscene system via DialogueSystem.
		mode = Mode::WaitingForCutscene;
		if (onCutsceneStartNeeded)
			onCutsceneStartNeeded(node.cutsceneId, node.next);
		return true;
	}

	stop();
	return false;
}

void DialogueRuntime::presentLine(const Node& node) {
	mode = Mode::PresentingLine;
	revealCharacters = 0.0f;
	presentation.mode = PresentationMode::Dialogue;
	presentation.speaker = node.speaker;
	presentation.fullText = node.text;
	presentation.visibleText.clear();
	presentation.portraitPath = node.portrait;
	presentation.backgroundPath.clear();
	presentation.choices.clear();
	presentation.selectedChoice = -1;
	presentation.revealCompleted = node.text.empty();
	presentation.showCutsceneSubtitle = false;
	presentation.cutsceneSkippable = false;
	presentation.cutsceneCamera = {};
	presentation.cutsceneImages.clear();
	presentation.cutsceneGlobalFadeAlpha = 1.0f;
	presentation.cutsceneBlackAlpha = 0.0f;

	if (presentation.revealCompleted) {
		presentation.visibleText = node.text;
		revealCharacters = static_cast<float>(node.text.size());
	}

	applyQuestActions(node.questUnlock, node.questComplete, node.questFail,
	                  node.objectiveComplete, node.objectiveVisible);
	if (!node.luaCallback.empty() && onDialogueLineStarted) {
		onDialogueLineStarted(node.luaCallback);
	}
	if (!node.chatBubble.empty() && onChatBubbleReady) {
		onChatBubbleReady(node.text, node.chatBubble == "in");
	}
}

void DialogueRuntime::presentChoices(const Node& node) {
	visibleChoices.clear();
	presentation.choices.clear();

	for (const Choice& choice : node.choices) {
		if (!choice.id.empty() && consumedChoices.count(choice.id) > 0) continue;
		if (!evaluateConditions(choice.conditions)) continue;
		visibleChoices.push_back(choice);
		presentation.choices.push_back({ choice.id, choice.text, choice.kind });
	}

	if (visibleChoices.empty()) {
		if (!node.next.empty()) {
			enterNode(node.next);
		}
		else {
			stop();
		}
		return;
	}

	mode = Mode::WaitingForChoice;
	selectedChoice = -1;
	presentation.mode = PresentationMode::Choice;
	presentation.speaker = node.speaker;
	presentation.fullText = node.text;
	presentation.visibleText = node.text;
	presentation.portraitPath = node.portrait;
	presentation.backgroundPath.clear();
	presentation.selectedChoice = -1;
	presentation.revealCompleted = true;
	presentation.showCutsceneSubtitle = false;
	presentation.cutsceneSkippable = false;
	presentation.cutsceneCamera = {};
	presentation.cutsceneImages.clear();
	presentation.cutsceneGlobalFadeAlpha = 1.0f;
	presentation.cutsceneBlackAlpha = 0.0f;
}

} // namespace ZL::Dialogue