// opt/scorekeeper.js
import cron from 'node-cron';
import { SlashCommandBuilder, EmbedBuilder, PermissionFlagsBits } from 'discord.js';

// Module state container
const moduleState = {
	cronJobs: new Map(), // Store cron jobs by client ID
};

/**
 * Initialize the scorekeeper module
 */
export const init = async (client, config) => {
	client.logger.info('Initializing Scorekeeper module');

	// Check if configuration exists
	if (!config.scorekeeper) {
		client.logger.warn('Scorekeeper configuration missing, using defaults');
		config.scorekeeper = {
			baseOutput: 1000,
			commendationValue: 1.0,
			citationValue: 1.2,
			decay: 90,
			schedule: '0 0 * * 0' // Default: weekly at midnight on Sunday
		};
	}

	// Check if scorekeeper collection exists
	await checkCollection(client);

	// Create scorekeeper interface on client
	client.scorekeeper = {
		addInput: (guildId, userId, amount) => addInput(client, guildId, userId, amount),
		addOutput: (guildId, userId, amount) => addOutput(client, guildId, userId, amount),
		addCommendation: (guildId, userId, amount = 1) => addCommendation(client, guildId, userId, amount),
		addCitation: (guildId, userId, amount = 1) => addCitation(client, guildId, userId, amount),
		getScore: (guildId, userId) => getScore(client, guildId, userId),
		getScores: (guildId, limit = 10) => getScores(client, guildId, limit),
		runDecay: (guildId) => runDecay(client, guildId)
	};

	// Set up cron job for decay
	setupDecayCron(client, config.scorekeeper.schedule);

	client.logger.info('Scorekeeper module initialized');
};

/**
 * Check if the scorekeeper collection exists in PocketBase
 */
async function checkCollection(client) {
	try {
		// Check if collection exists by trying to list records
		await client.pb.collection('scorekeeper').getList(1, 1);
		client.logger.info('Scorekeeper collection exists in PocketBase');
	} catch (error) {
		// If collection doesn't exist, log warning
		client.logger.warn('Scorekeeper collection does not exist in PocketBase');
		client.logger.warn('Please create a "scorekeeper" collection with fields:');
		client.logger.warn('- guildId (text, required)');
		client.logger.warn('- userId (text, required)');
		client.logger.warn('- input (number, default: 0)');
		client.logger.warn('- output (number, default: 0)');
		client.logger.warn('- commendations (number, default: 0)');
		client.logger.warn('- citations (number, default: 0)');
		client.logger.warn('- lastDecay (date, required)');
	}
}

/**
 * Set up cron job for decay
 */
function setupDecayCron(client, schedule) {
	try {
		// Validate cron expression
		if (!cron.validate(schedule)) {
			client.logger.error(`Invalid cron schedule: ${schedule}, using default`);
			schedule = '0 0 * * 0'; // Default: weekly at midnight on Sunday
		}

		// Create and start the cron job
		const job = cron.schedule(schedule, async () => {
			client.logger.info('Running scheduled score decay');

			try {
				// Get all guilds the bot is in
				const guilds = client.guilds.cache.map(guild => guild.id);

				// Run decay for each guild
				for (const guildId of guilds) {
					await runDecay(client, guildId);
				}

				client.logger.info('Score decay completed');
			} catch (error) {
				client.logger.error(`Error during scheduled score decay: ${error.message}`);
			}
		});

		// Store the job in module state
		moduleState.cronJobs.set(client.config.id, job);

		client.logger.info(`Score decay scheduled with cron: ${schedule}`);
	} catch (error) {
		client.logger.error(`Failed to set up decay cron job: ${error.message}`);
	}
}

/**
 * Add input points for a user
 */
async function addInput(client, guildId, userId, amount) {
	if (!guildId || !userId || !amount || amount <= 0) {
		throw new Error(`Invalid parameters for addInput - guildId: ${guildId}, userId: ${userId}, amount: ${amount}`);
	}

	try {
		// Get or create user record
		const scoreData = await getOrCreateScoreData(client, guildId, userId);

		// Calculate new input score
		const newInput = scoreData.input + amount;

		client.logger.debug(`Updating record ${scoreData.id} - input from ${scoreData.input} to ${newInput}`);

		// Use direct update with ID to avoid duplicate records
		return await client.pb.collection('scorekeeper').update(scoreData.id, {
			input: newInput
		});
	} catch (error) {
		client.logger.error(`Error adding input points: ${error.message}`);
		throw error;
	}
}

/**
 * Add output points for a user
 */
async function addOutput(client, guildId, userId, amount) {
	if (!guildId || !userId || !amount || amount <= 0) {
		throw new Error('Invalid parameters for addOutput');
	}

	try {
		// Get or create user record
		const scoreData = await getOrCreateScoreData(client, guildId, userId);

		// Calculate new output score
		const newOutput = scoreData.output + amount;

		client.logger.debug(`Updating record ${scoreData.id} - output from ${scoreData.output} to ${newOutput}`);

		// Use direct update with ID to avoid duplicate records
		return await client.pb.collection('scorekeeper').update(scoreData.id, {
			output: newOutput
		});
	} catch (error) {
		client.logger.error(`Error adding output points: ${error.message}`);
		throw error;
	}
}

/**
 * Add commendations for a user
 */
async function addCommendation(client, guildId, userId, amount = 1) {
	if (!guildId || !userId || amount <= 0) {
		throw new Error('Invalid parameters for addCommendation');
	}

	try {
		// Log the search to debug
		client.logger.debug(`Looking for record with guildId=${guildId} and userId=${userId}`);

		// Get or create user record
		const scoreData = await getOrCreateScoreData(client, guildId, userId);

		// Log the found/created record
		client.logger.debug(`Found/created record with ID: ${scoreData.id}`);

		// Calculate new commendations value
		const newCommendations = scoreData.commendations + amount;

		// Log the update attempt
		client.logger.debug(`Updating record ${scoreData.id} - commendations from ${scoreData.commendations} to ${newCommendations}`);

		// Use direct update with ID to avoid duplicate records
		return await client.pb.collection('scorekeeper').update(scoreData.id, {
			commendations: newCommendations
		});
	} catch (error) {
		client.logger.error(`Error adding commendations: ${error.message}`);
		throw error;
	}
}

/**
 * Add citations for a user
 */
async function addCitation(client, guildId, userId, amount = 1) {
	if (!guildId || !userId || amount <= 0) {
		throw new Error('Invalid parameters for addCitation');
	}

	try {
		// Get or create user record
		const scoreData = await getOrCreateScoreData(client, guildId, userId);

		// Calculate new citations value
		const newCitations = scoreData.citations + amount;

		client.logger.debug(`Updating record ${scoreData.id} - citations from ${scoreData.citations} to ${newCitations}`);

		// Use direct update with ID to avoid duplicate records
		return await client.pb.collection('scorekeeper').update(scoreData.id, {
			citations: newCitations
		});
	} catch (error) {
		client.logger.error(`Error adding citations: ${error.message}`);
		throw error;
	}
}

/**
 * Get a user's score
 */
async function getScore(client, guildId, userId) {
	if (!guildId || !userId) {
		throw new Error('Guild ID and User ID are required');
	}

	try {
		// Get score data, create if not exists
		const scoreData = await getOrCreateScoreData(client, guildId, userId);

		// Calculate total score
		const totalScore = calculateScore(
			scoreData,
			client.config.scorekeeper.baseOutput,
			client.config.scorekeeper.commendationValue,
			client.config.scorekeeper.citationValue
		);

		return {
			...scoreData,
			totalScore
		};
	} catch (error) {
		client.logger.error(`Error getting score: ${error.message}`);
		throw error;
	}
}

/**
 * Get scores for a guild
 */
async function getScores(client, guildId, limit = 10) {
	if (!guildId) {
		throw new Error('Guild ID is required');
	}

    try {
        // Fetch all score records for this guild
        const records = await client.pb.collection('scorekeeper').getFullList({
            filter: `guildId = "${guildId}"`
        });
        // Compute totalScore for each, then sort and limit
        const scored = records.map(record => {
            const totalScore = calculateScore(
                record,
                client.config.scorekeeper.baseOutput,
                client.config.scorekeeper.commendationValue,
                client.config.scorekeeper.citationValue
            );
            return { ...record, totalScore };
        });
        // Sort descending by score
        scored.sort((a, b) => b.totalScore - a.totalScore);
        // Return top 'limit' entries
        return scored.slice(0, limit);
    } catch (error) {
        client.logger.error(`Error getting scores: ${error.message}`);
        throw error;
    }
}

/**
 * Run decay process for a guild
 */
async function runDecay(client, guildId) {
	if (!guildId) {
		throw new Error('Guild ID is required');
	}

	try {
		const decayFactor = client.config.scorekeeper.decay / 100;
		const baseOutput = client.config.scorekeeper.baseOutput;

		// Get all records for this guild
		const records = await client.pb.collection('scorekeeper').getFullList({
			filter: `guildId = "${guildId}"`
		});

		// Update each record with decay
		let updatedCount = 0;
		for (const record of records) {
			try {
				const newInput = Math.floor(record.input * decayFactor);

				// Calculate new output, but ensure it never falls below baseOutput
				let newOutput = Math.floor(record.output * decayFactor);
				if (newOutput < baseOutput) {
					newOutput = baseOutput;
					client.logger.debug(`Output for record ${record.id} would fall below BaseOutput - setting to ${baseOutput}`);
				}

				// Update record directly
				await client.pb.collection('scorekeeper').update(record.id, {
					input: newInput,
					output: newOutput,
					lastDecay: new Date().toISOString()
				});

				updatedCount++;
			} catch (updateError) {
				client.logger.error(`Error updating record ${record.id} during decay: ${updateError.message}`);
			}
		}

		client.logger.info(`Decay completed for guild ${guildId}: ${updatedCount} records updated`);
		return updatedCount;
	} catch (error) {
		client.logger.error(`Error running decay: ${error.message}`);
		throw error;
	}
}

/**
 * Calculate score based on formula (no scaling factor)
 * Formula: (1 + C*commendationValue - D*citationValue) * (input / (output + baseOutput))
 */
function calculateScore(data, baseOutput, commendationValue, citationValue) {
    const multiplier = 1 + (data.commendations * commendationValue) - (data.citations * citationValue);
    const activityScore = data.input / (data.output + baseOutput);

    // Removed aesthetic scaling (×100) for raw score
    return multiplier * activityScore;
}

/**
 * Get or create score data for a user in a guild
 */
async function getOrCreateScoreData(client, guildId, userId) {
	try {
		// Always try to get existing record first
		let existingRecord = null;
		const baseOutput = client.config.scorekeeper.baseOutput;

		// Try to find the record using filter
		try {
			existingRecord = await client.pb.collection('scorekeeper').getFirstListItem(
				`guildId = "${guildId}" && userId = "${userId}"`
			);

			client.logger.debug(`Found existing score record for ${userId} in guild ${guildId}`);
			return existingRecord;
		} catch (error) {
			// Only create new record if specifically not found (404)
			if (error.status === 404) {
				client.logger.debug(`No existing score record found, creating new one for ${userId} in guild ${guildId}`);

				// Create new record with default values
				// Note: output is now initialized to baseOutput instead of 0
				const newData = {
					guildId,
					userId,
					input: 0,
					output: baseOutput, // Initialize to baseOutput, not 0
					commendations: 0,
					citations: 0,
					lastDecay: new Date().toISOString()
				};

				return await client.pb.collection('scorekeeper').create(newData);
			}

			// For any other error, rethrow
			client.logger.error(`Error searching for score record: ${error.message}`);
			throw error;
		}
	} catch (error) {
		client.logger.error(`Error in getOrCreateScoreData: ${error.message}`);
		throw error;
	}
}

// Define slash commands for the module
export const commands = [
	// Command to view a user's score
	{
		data: new SlashCommandBuilder()
			.setName('score')
 .setDescription('View your I/O score or another user\'s I/O score')
				.addUserOption(option =>
					option.setName('user')
 .setDescription('User to check I/O score for (defaults to you)')
						.setRequired(false)
				)
				.addBooleanOption(option =>
					option.setName('ephemeral')
						.setDescription('Whether the response should be ephemeral')
						.setRequired(false)
				),

		execute: async (interaction, client) => {
			const targetUser = interaction.options.getUser('user') || interaction.user;
            const ephemeral = interaction.options.getBoolean('ephemeral') ?? true;
            // Wrap score retrieval and embed generation in try/catch to handle errors gracefully
            try {

            // Fetch score data
            const baseOutput = client.config.scorekeeper.baseOutput;
            const commendationValue = client.config.scorekeeper.commendationValue;
            const citationValue = client.config.scorekeeper.citationValue;
            const scoreData = await client.scorekeeper.getScore(interaction.guildId, targetUser.id);
            const embed = new EmbedBuilder()
            .setTitle(`I/O Score for ${(await interaction.guild.members.fetch(targetUser.id).catch(() => null))?.displayName || targetUser.username}`)
					.setColor(0x00AE86)
					.setThumbnail(targetUser.displayAvatarURL())
					.addFields(
						{ name: 'Total Score', value: `**${scoreData.totalScore.toFixed(2)}**`, inline: false },
                { name: 'Commendations', value: `**${scoreData.commendations}** x ${commendationValue}`, inline: false },
                { name: 'Citations', value: `**${scoreData.citations}** x ${citationValue}`, inline: false },
						{ name: 'Input Score', value: `**${scoreData.input}**`, inline: true },
						{ name: 'Output Score', value: `**${scoreData.output}** + ${baseOutput}`, inline: true }
					)
					.setFooter({ text: 'Last decay: ' + new Date(scoreData.lastDecay).toLocaleDateString() })
					.setTimestamp();

                await interaction.reply({ embeds: [embed], ephemeral });
            } catch (error) {
                client.logger.error(`Error in score command: ${error.message}`);
                try {
                    await interaction.reply({ content: 'Failed to retrieve I/O score.', ephemeral });
                } catch {}
            }
		}
	},

	// Command to view top scores
	{
		data: new SlashCommandBuilder()
			.setName('leaderboard')
 .setDescription('View the server\'s I/O score leaderboard')
               .addBooleanOption(option =>
                   option.setName('ephemeral')
                       .setDescription('Whether the response should be ephemeral')
                       .setRequired(false)
               ),

		execute: async (interaction, client) => {
       const ephemeral = interaction.options.getBoolean('ephemeral') ?? true;
       await interaction.deferReply({ ephemeral });

			const limit = 10;

			try {
				const scores = await client.scorekeeper.getScores(interaction.guildId, limit);

				if (scores.length === 0) {
					return interaction.editReply('No scores found for this server.');
				}

				// Format leaderboard
				const guild = interaction.guild;
				let leaderboardText = '';

				for (let i = 0; i < scores.length; i++) {
					const score = scores[i];
					const user = await guild.members.fetch(score.userId).catch(() => null);
					const displayName = user ? user.displayName : 'Unknown User';

					leaderboardText += `${i + 1}. **${displayName}**: ${score.totalScore.toFixed(2)}\n`;
				}

				const embed = new EmbedBuilder()
            .setTitle('I/O Score Leaderboard')
					.setColor(0x00AE86)
					.setDescription(leaderboardText)
					.setFooter({ text: `Showing top ${scores.length} users` })
					.setTimestamp();

				await interaction.editReply({ embeds: [embed] });
			} catch (error) {
				client.logger.error(`Error in leaderboard command: ${error.message}`);
				await interaction.editReply('Failed to retrieve leaderboard data.');
			}
		}
	},

	// Command to give a commendation (admin only)
	{
		data: new SlashCommandBuilder()
			.setName('commend')
			.setDescription('Give a commendation to a user (Admin only)')
			.addUserOption(option => 
				option.setName('user')
					.setDescription('User to commend')
					.setRequired(true))
			.addIntegerOption(option => 
				option.setName('amount')
					.setDescription('Amount of commendations (default: 1)')
					.setRequired(false)
					.setMinValue(1)
					.setMaxValue(10))
			.setDefaultMemberPermissions(PermissionFlagsBits.Administrator),

		execute: async (interaction, client) => {
			const targetUser = interaction.options.getUser('user');
			const amount = interaction.options.getInteger('amount') || 1;

			try {
				await client.scorekeeper.addCommendation(interaction.guildId, targetUser.id, amount);

				await interaction.reply(`Added ${amount} commendation${amount !== 1 ? 's' : ''} to ${targetUser}.`);
			} catch (error) {
				client.logger.error(`Error in commend command: ${error.message}`);
				await interaction.reply({ 
					content: 'Failed to add commendation.', 
					ephemeral: true 
				});
			}
		}
	},

	// Command to give a citation (admin only)
	{
		data: new SlashCommandBuilder()
			.setName('cite')
			.setDescription('Give a citation to a user (Admin only)')
			.addUserOption(option => 
				option.setName('user')
					.setDescription('User to cite')
					.setRequired(true))
			.addIntegerOption(option => 
				option.setName('amount')
					.setDescription('Amount of citations (default: 1)')
					.setRequired(false)
					.setMinValue(1)
					.setMaxValue(10))
			.setDefaultMemberPermissions(PermissionFlagsBits.Administrator),

		execute: async (interaction, client) => {
			const targetUser = interaction.options.getUser('user');
			const amount = interaction.options.getInteger('amount') || 1;

			try {
				await client.scorekeeper.addCitation(interaction.guildId, targetUser.id, amount);

				await interaction.reply(`Added ${amount} citation${amount !== 1 ? 's' : ''} to ${targetUser}.`);
			} catch (error) {
				client.logger.error(`Error in cite command: ${error.message}`);
				await interaction.reply({ 
					content: 'Failed to add citation.', 
					ephemeral: true 
				});
			}
		}
	},

	// Command to manually run decay (admin only)
	{
		data: new SlashCommandBuilder()
			.setName('run-decay')
			.setDescription('Manually run score decay (Admin only)')
			.setDefaultMemberPermissions(PermissionFlagsBits.Administrator),

		execute: async (interaction, client) => {
			await interaction.deferReply();

			try {
				const updatedCount = await client.scorekeeper.runDecay(interaction.guildId);

				await interaction.editReply(`Score decay completed. Updated ${updatedCount} user records.`);
			} catch (error) {
				client.logger.error(`Error in run-decay command: ${error.message}`);
				await interaction.editReply('Failed to run score decay.');
			}
		}
	}
];