miracle-api 0.6.0

use serde::{Deserialize, Serialize};
use solana_program::hash::hashv;
use steel::*;

use crate::{
    consts::*,
    dmt::{DailyParticipantData, EpochClaimData, SocialClaimData},
    instruction::*,
    state::{config_pda, metrics_pda, proof_pda, snapshot_pda, treasury_pda},
};

/// Builds a claim instruction.
///
/// The reward amount is calculated on-chain using the transparent formula:
/// reward = (activity_count * customer_reward_pool) / total_customer_activity
///
/// Where:
/// - `activity_count` is extracted from the participant data
/// - `customer_reward_pool` and `total_customer_activity` are read from epoch data
///
/// ## Parameters
/// - `signer`: The wallet signing the transaction
/// - `beneficiary`: The wallet receiving the rewards
/// - `epoch`: The epoch number for the claim
/// - `participant_data`: Participant data including activity count and timestamps
/// - `payment_proof`: Merkle proof path for payment verification
/// - `payment_indices`: Merkle proof path indices (true = right, false = left)
/// - `seal_proof`: Merkle proof path for seal verification
/// - `seal_indices`: Merkle proof path indices (true = right, false = left)
/// - `payment_root`: Payment merkle root for verification
/// - `epoch_data`: Epoch-specific data for accurate reward calculation
/// - `participant_type`: 0 for customer, 1 for merchant
/// - `social_data`: Optional social media engagement data
///
/// ## Returns
/// - Instruction for claiming rewards
///
/// ## Note
/// Users can estimate their rewards off-chain using the transparent calculation functions
/// in `consts.rs`. The on-chain calculation will match the off-chain estimation exactly.
pub fn claim(
    signer: Pubkey,
    beneficiary: Pubkey,
    epoch: u64,
    participant_data: DailyParticipantData,
    payment_proof: Vec<[u8; 32]>,
    payment_indices: Vec<bool>,
    seal_proof: Vec<[u8; 32]>,
    seal_indices: Vec<bool>,
    payment_root: [u8; 32],
    epoch_data: EpochClaimData,
    participant_type: u8,
    social_data: Option<SocialClaimData>,
) -> Instruction {
    let mut data = Vec::new();

    // Use the Claim struct's to_bytes() method for consistent serialization
    let claim_data = Claim {
        epoch: epoch.to_le_bytes(),
        payment_proof_length: payment_proof.len() as u8,
        seal_proof_length: seal_proof.len() as u8,
        participant_type,
        has_social: if social_data.is_some() { 1u8 } else { 0u8 },
        _padding: [0u8; 4],
    };
    data.extend_from_slice(&claim_data.to_bytes());

    // Append participant data
    data.extend_from_slice(bytemuck::bytes_of(&participant_data));

    // Append payment proof data
    for path_node in payment_proof {
        data.extend_from_slice(&path_node);
    }

    // Append payment indices data
    for &is_right in &payment_indices {
        data.push(if is_right { 1u8 } else { 0u8 });
    }

    // Append seal proof data
    for path_node in seal_proof {
        data.extend_from_slice(&path_node);
    }

    // Append seal indices data
    for &is_right in &seal_indices {
        data.push(if is_right { 1u8 } else { 0u8 });
    }

    // Append payment root data
    data.extend_from_slice(&payment_root);

    // Append epoch data
    data.extend_from_slice(bytemuck::bytes_of(&epoch_data));

    // Append social data if provided
    if let Some(social) = social_data {
        data.extend_from_slice(bytemuck::bytes_of(&social));
    }

    let proof_pda = proof_pda(signer);
    Instruction {
        program_id: crate::ID,
        accounts: vec![
            AccountMeta::new(signer, true),                     // [0] signer
            AccountMeta::new(beneficiary, false),               // [1] beneficiary
            AccountMeta::new(proof_pda.0, false),               // [2] proof PDA
            AccountMeta::new(TREASURY_ADDRESS, false),          // [3] treasury
            AccountMeta::new(TREASURY_TOKENS_ADDRESS, false),   // [4] treasury tokens
            AccountMeta::new_readonly(spl_token::ID, false),    // [5] token program
            AccountMeta::new_readonly(SNAPSHOT_ADDRESS, false), // [6] snapshot
            AccountMeta::new_readonly(CONFIG_ADDRESS, false),   // [7] config
        ],
        data,
    }
}

/// Create social claim data for social media engagement.
///
/// This function creates a `SocialClaimData` struct with the provided social media
/// information. The oracle signature should be provided by the authorized oracle
/// authority.
///
/// ## Parameters
/// - `post_url`: Social media post URL (max 256 bytes)
/// - `engagement_score`: Engagement score for the post (u32)
/// - `post_timestamp`: Unix timestamp when post was made (i64)
/// - `oracle_signature`: Ed25519 signature from authorized oracle
///
/// ## Oracle Signature Requirements
/// The oracle must sign a message with the following format:
///
/// `epoch:user_pubkey:post_url:engagement_score:post_timestamp`
///
/// This format prevents replay attacks by including epoch and user context.
///
/// ## Returns
/// - `SocialClaimData` struct ready for social claim
///
/// ## Example
/// ```rust
/// use miracle_api::sdk::create_social_claim_data;
///
/// let social_data = create_social_claim_data(
///     "https://twitter.com/user/123",
///     500,
///     1640995200,
///     &[0u8; 64], // Oracle signature
/// );
/// ```
pub fn create_social_claim_data(
    post_url: &str,
    engagement_score: u32,
    post_timestamp: i64,
    oracle_signature: &[u8; 64],
) -> SocialClaimData {
    let mut post_url_bytes = [0u8; 256];
    let url_bytes = post_url.as_bytes();
    let copy_len = std::cmp::min(url_bytes.len(), 256);
    post_url_bytes[..copy_len].copy_from_slice(&url_bytes[..copy_len]);

    SocialClaimData {
        post_url: post_url_bytes,
        oracle_signature: *oracle_signature,
        engagement_score: engagement_score.to_le_bytes(),
        post_timestamp: post_timestamp.to_le_bytes(),
        _padding: [0u8; 4],
    }
}

/// Validate social media post URL for required content.
///
/// This function checks if the social media post URL contains the required
/// hashtags and mentions for social marketing rewards.
///
/// ## Parameters
/// - `post_url`: Social media post URL to validate
///
/// ## Returns
/// - `true` if the URL contains required content, `false` otherwise
///
/// ## Required Content
/// - Must contain `#MiracleRewards` hashtag
/// - Must contain `@MiracleProtocol` mention
/// - URL must be from supported platforms (Twitter, Instagram, etc.)
pub fn validate_social_post_url(post_url: &str) -> bool {
    let url_lower = post_url.to_lowercase();

    // Check for required hashtag
    if !url_lower.contains("#miraclerewards") {
        return false;
    }

    // Check for required mention
    if !url_lower.contains("@miracleprotocol") {
        return false;
    }

    // Check for supported platforms
    let supported_platforms = [
        "twitter.com",
        "x.com",
        "instagram.com",
        "facebook.com",
        "linkedin.com",
        "tiktok.com",
    ];

    supported_platforms
        .iter()
        .any(|platform| url_lower.contains(platform))
}

/// Calculate social reward amount based on engagement and base reward.
///
/// This function calculates the social reward amount based on the engagement
/// score and the base reward per post. The calculation matches the on-chain
/// logic used in the social claim instruction.
///
/// ## Parameters
/// - `engagement_score`: Engagement metrics for the social post
/// - `base_reward_per_post`: Base reward amount per post
///
/// ## Returns
/// - Total reward amount (base reward + engagement bonus)
///
/// ## Formula
/// - Base reward: `base_reward_per_post`
/// - Engagement bonus: `(engagement_score - 1000) / 100` if score > 1000
/// - Total reward: `base_reward + engagement_bonus`
pub fn calculate_social_reward_amount(engagement_score: u32, base_reward_per_post: u32) -> u64 {
    let base_reward = base_reward_per_post as u64;
    let engagement_score_u64 = engagement_score as u64;

    let engagement_bonus = if engagement_score_u64 > 1000 {
        (engagement_score_u64 - 1000) / 100 // 1 MIRACLE per 100 engagement points above 1000
    } else {
        0
    };

    base_reward + engagement_bonus
}

/// Builds a social claim instruction.
///
/// This instruction allows users to claim social marketing rewards based on their
/// social media engagement. Social rewards require payment activity in the same epoch
/// and are verified through oracle signatures to prevent gaming.
///
/// ## Parameters
/// - `signer`: The wallet signing the transaction
/// - `beneficiary`: The wallet receiving the rewards
/// - `epoch`: The epoch number for the claim (payment activity required)
/// - `merkle_root`: Merkle root for payment verification
/// - `merkle_path`: Merkle proof path for payment activity
/// - `path_indices`: Merkle proof path indices (true = right, false = left)
/// - `participant_type`: 0 for customer, 1 for merchant
/// - `social_data`: Social media verification data
///
/// ## Returns
/// - Instruction for claiming social rewards
///
/// ## Requirements

/// Builds a close instruction.
///
/// This instruction allows a user to close their Proof account and recover the rent.
/// The Proof account can only be closed if:
/// 1. The signer is the Proof account owner (authority)
/// 2. No rewards have been claimed (total_claimed_rewards == 0)
///
/// ## Accounts
/// - `signer`: The Proof account owner (must be a signer)
/// - `proof`: The Proof account to close (PDA derived from signer)
/// - `system_program`: System program for rent recovery
///
/// ## Safety Features
/// - **Owner-only**: Only the Proof account owner can close it
/// - **No claims allowed**: Cannot close if rewards have been claimed
/// - **Rent recovery**: All rent is returned to the signer
///
/// ## Use Cases
/// - Recovering rent when no longer participating
/// - Clean account management
/// - Reopening with a fresh Proof account later
///
/// ## Returns
/// - Instruction for closing the Proof account
pub fn close(signer: Pubkey) -> Instruction {
    let proof = proof_pda(signer).0;
    Instruction {
        program_id: crate::ID,
        accounts: vec![
            AccountMeta::new(signer, true),
            AccountMeta::new(proof, false),
            AccountMeta::new_readonly(solana_program::system_program::ID, false),
        ],
        data: Close {}.to_bytes(),
    }
}

/// Builds an open instruction.
pub fn open(signer: Pubkey, payer: Pubkey) -> Instruction {
    let proof_pda = proof_pda(signer);
    Instruction {
        program_id: crate::ID,
        accounts: vec![
            AccountMeta::new(signer, true),
            AccountMeta::new(payer, true),
            AccountMeta::new(proof_pda.0, false),
            AccountMeta::new_readonly(solana_program::system_program::ID, false),
        ],
        data: Open {}.to_bytes(),
    }
}

/// Builds a reset instruction.
///
/// This instruction implements the Community-Driven Decay model by adjusting daily rewards
/// based on community health metrics stored in the Metrics account.
pub fn reset(signer: Pubkey) -> Instruction {
    Instruction {
        program_id: crate::ID,
        accounts: vec![
            AccountMeta::new(signer, true),
            AccountMeta::new(CONFIG_ADDRESS, false),
            AccountMeta::new_readonly(METRICS_ADDRESS, false),
            AccountMeta::new(MINT_ADDRESS, false),
            AccountMeta::new(TREASURY_ADDRESS, false),
            AccountMeta::new(TREASURY_TOKENS_ADDRESS, false),
            AccountMeta::new_readonly(spl_token::ID, false),
        ],
        data: Reset {}.to_bytes(),
    }
}

// MI: abandoned for community trust/confidence
// // Build an upgrade instruction.
// pub fn upgrade(signer: Pubkey, beneficiary: Pubkey, sender: Pubkey, amount: u64) -> Instruction {
//     Instruction {
//         program_id: crate::ID,
//         accounts: vec![
//             AccountMeta::new(signer, true),
//             AccountMeta::new(beneficiary, false),
//             AccountMeta::new(MINT_ADDRESS, false),
//             AccountMeta::new(MINT_V1_ADDRESS, false),
//             AccountMeta::new(sender, false),
//             AccountMeta::new(TREASURY_ADDRESS, false),
//             AccountMeta::new_readonly(spl_token::ID, false),
//             AccountMeta::new_readonly(CONFIG_ADDRESS, false),
//         ],
//         data: Upgrade {
//             amount: amount.to_le_bytes(),
//         }
//         .to_bytes(),
//     }
// }

// /// Build an evolve instruction.
// pub fn evolve(signer: Pubkey, evolvable: bool) -> Instruction {
//     Instruction {
//         program_id: crate::ID,
//         accounts: vec![
//             AccountMeta::new(signer, true),
//             AccountMeta::new(CONFIG_ADDRESS, false),
//         ],
//         data: Evolve {
//             evolvable: evolvable as u8,
//         }
//         .to_bytes(),
//     }
// }

/// Builds an initialize instruction.
pub fn initialize(signer: Pubkey, project_wallet: Pubkey) -> Instruction {
    let config_pda = config_pda();
    let mint_pda = Pubkey::find_program_address(&[MINT, MINT_NOISE.as_slice()], &crate::ID);
    let treasury_pda = treasury_pda();
    let snapshot_pda = snapshot_pda();
    let metrics_pda = metrics_pda();
    let metadata_pda = Pubkey::find_program_address(
        &[
            METADATA,
            mpl_token_metadata::ID.as_ref(),
            mint_pda.0.as_ref(),
        ],
        &mpl_token_metadata::ID,
    );
    // let treasury_tokens_pda = Pubkey::find_program_address(
    //     &[
    //         treasury_pda.0.as_ref(),
    //         spl_token::id().as_ref(),
    //         MINT_ADDRESS.as_ref(),
    //     ],
    //     &spl_associated_token_account::id(),
    // );
    let project_tokens_pda = Pubkey::find_program_address(
        &[
            project_wallet.as_ref(),
            spl_token::id().as_ref(),
            MINT_ADDRESS.as_ref(),
        ],
        &spl_associated_token_account::id(),
    );

    Instruction {
        program_id: crate::ID,
        accounts: vec![
            AccountMeta::new(signer, true),
            AccountMeta::new(config_pda.0, false),
            AccountMeta::new(snapshot_pda.0, false),
            AccountMeta::new(metrics_pda.0, false),
            AccountMeta::new(metadata_pda.0, false),
            AccountMeta::new(mint_pda.0, false),
            AccountMeta::new(treasury_pda.0, false),
            AccountMeta::new(TREASURY_TOKENS_ADDRESS, false),
            AccountMeta::new(project_wallet, false),
            AccountMeta::new(project_tokens_pda.0, false),
            AccountMeta::new_readonly(system_program::ID, false),
            AccountMeta::new_readonly(spl_token::ID, false),
            AccountMeta::new_readonly(spl_associated_token_account::ID, false),
            AccountMeta::new_readonly(mpl_token_metadata::ID, false),
            AccountMeta::new_readonly(sysvar::rent::ID, false),
        ],
        data: Initialize { project_wallet }.to_bytes(),
    }
}

/// Builds an update oracle instruction.
///
/// This instruction allows the current oracle authority to update itself to a new oracle authority.
/// Only the current oracle authority can execute this instruction.
///
/// ## Parameters
/// - `oracle`: The current oracle authority public key (must be a signer)
/// - `new_oracle_authority`: The new oracle authority public key
///
/// ## Returns
/// An instruction that can be included in a transaction to update the oracle authority.
///
/// ## Security
/// - Only the current oracle authority can execute this instruction
/// - New oracle authority must be different from current and not zero
/// - Both main and social oracle authorities are updated consistently
///
/// ## Example
/// ```rust,no_run
/// use steel::Pubkey;
/// let current_oracle = Pubkey::new_unique();
/// let new_oracle = Pubkey::new_unique();
/// let instruction = miracle_api::sdk::update_oracle(current_oracle, new_oracle);
/// ```
pub fn update_oracle(oracle: Pubkey, new_oracle_authority: Pubkey) -> Instruction {
    Instruction {
        program_id: crate::ID,
        accounts: vec![
            AccountMeta::new(oracle, true),
            AccountMeta::new(CONFIG_ADDRESS, false),
        ],
        data: UpdateOracle {
            new_oracle_authority,
        }
        .to_bytes(),
    }
}

/// Builds an update snapshot instruction.
pub fn update_snapshot(
    oracle: Pubkey,
    epoch: u64,
    seal_merkle_root: [u8; 32],
    payment_merkle_root: [u8; 32],
    epoch_hash: [u8; 32],
    customer_reward_pool: u64,
    merchant_reward_pool: u64,
    customer_participants: u32,
    merchant_participants: u32,
    total_customer_payments: u32,
    total_merchant_payments: u32,
) -> Instruction {
    Instruction {
        program_id: crate::ID,
        accounts: vec![
            AccountMeta::new(oracle, true),
            AccountMeta::new(SNAPSHOT_ADDRESS, false),
            AccountMeta::new_readonly(CONFIG_ADDRESS, false),
            AccountMeta::new(TREASURY_ADDRESS, false),
        ],
        data: UpdateSnapshot {
            epoch: epoch.to_le_bytes(),
            seal_merkle_root,
            payment_merkle_root,
            epoch_hash,
            customer_reward_pool: customer_reward_pool.to_le_bytes(),
            merchant_reward_pool: merchant_reward_pool.to_le_bytes(),
            customer_participants: customer_participants.to_le_bytes(),
            merchant_participants: merchant_participants.to_le_bytes(),
            total_customer_payments: total_customer_payments.to_le_bytes(),
            total_merchant_payments: total_merchant_payments.to_le_bytes(),
        }
        .to_bytes(),
    }
}

/// Builds an update community metrics instruction.
///
/// This function creates an instruction to update community health metrics used for
/// the Enhanced Community-Driven Decay model. Only the oracle authority can execute this instruction.
///
/// ## Parameters
/// - `oracle`: The oracle authority public key (must be a signer)
/// - `weekly_active_users`: Number of active users in the past week
/// - `weekly_retention_rate`: Retention rate in basis points (0-10000, 0-100%)
/// - `user_weight`: User weight in basis points (0-10000) for weighted geometric mean
/// - `volume_weight`: Volume weight in basis points (0-10000) for weighted geometric mean
/// - `retention_weight`: Retention weight in basis points (0-10000) for weighted geometric mean
///
/// ## Returns
/// An instruction that can be included in a transaction to update community metrics.
///
/// ## Security
/// - The oracle must be a signer of the transaction
/// - Input validation occurs on-chain
/// - Only the authorized oracle can update metrics
///
/// ## Example
/// ```rust,no_run
/// use steel::Pubkey;
/// let oracle_pubkey = Pubkey::new_unique();
/// let instruction = miracle_api::sdk::update_metrics(
///     oracle_pubkey,
///     5000,        // 5,000 active users
///     7500,        // 75% retention rate
///     4000,        // 40% user weight
///     3500,        // 35% activity weight
///     2500,        // 25% retention weight
///     50_000,      // 50,000 transactions
///     7000,        // 70% customer reward share
///     3000,        // 30% merchant reward share
/// );
/// ```
pub fn update_metrics(
    oracle: Pubkey,
    weekly_active_users: u32,
    weekly_retention_rate: u16,
    user_weight: u16,
    activity_weight: u16,
    retention_weight: u16,
    weekly_activity_count: u32,
    customer_reward_share: u16,
    merchant_reward_share: u16,
) -> Instruction {
    Instruction {
        program_id: crate::ID,
        accounts: vec![
            AccountMeta::new(oracle, true),
            AccountMeta::new(METRICS_ADDRESS, false),
            AccountMeta::new_readonly(CONFIG_ADDRESS, false),
        ],
        data: UpdateMetrics {
            weekly_active_users: weekly_active_users.to_le_bytes(),
            weekly_retention_rate: weekly_retention_rate.to_le_bytes(),
            user_weight: user_weight.to_le_bytes(),
            activity_weight: activity_weight.to_le_bytes(),
            retention_weight: retention_weight.to_le_bytes(),
            weekly_activity_count: weekly_activity_count.to_le_bytes(),
            customer_reward_share: customer_reward_share.to_le_bytes(),
            merchant_reward_share: merchant_reward_share.to_le_bytes(),
            _padding: [0u8; 4], // 4 bytes padding for 8-byte alignment
        }
        .to_bytes(),
    }
}

/// Validates community metrics parameters before creating an instruction.
///
/// This function helps oracles validate their inputs before submitting transactions,
/// providing better error handling and user experience.
///
/// ## Parameters
/// - `weekly_active_users`: Number of active users in the past week
/// - `weekly_retention_rate`: Retention rate in basis points (0-10000, 0-100%)
/// - `user_weight`: User weight in basis points (0-10000) for weighted geometric mean
/// - `activity_weight`: Activity weight in basis points (0-10000) for weighted geometric mean
/// - `retention_weight`: Retention weight in basis points (0-10000) for weighted geometric mean
/// - `weekly_activity_count`: Number of transactions in the past week
/// - `customer_reward_share`: Customer reward percentage in basis points (0-10000)
/// - `merchant_reward_share`: Merchant reward percentage in basis points (0-10000)
///
/// ## Returns
/// - `Ok(())` if all parameters are valid
/// - `Err(MiracleError)` with specific error if validation fails
///
/// ## Validation Rules
/// - Weights must sum to 10000 (100%)
/// - Reward shares must sum to 10000 (100%)
/// - Retention rate must be 0-10000 (0-100%)

/// - Activity count must be reasonable (0-1M transactions per week)
/// - All numeric values must be reasonable
pub fn validate_community_metrics(
    weekly_active_users: u32,
    weekly_retention_rate: u16,
    user_weight: u16,
    activity_weight: u16,
    retention_weight: u16,
    weekly_activity_count: u32,
    customer_reward_share: u16,
    merchant_reward_share: u16,
) -> Result<(), crate::error::MiracleError> {
    // Validate weights sum to 10000 (100%)
    let total_weight = user_weight
        .saturating_add(activity_weight)
        .saturating_add(retention_weight);
    if total_weight != 10000 {
        return Err(crate::error::MiracleError::InvalidWeights);
    }

    // Validate reward shares sum to 10000 (100%)
    let total_reward_share = customer_reward_share.saturating_add(merchant_reward_share);
    if total_reward_share != 10000 {
        return Err(crate::error::MiracleError::InvalidRewardSplit);
    }

    // Validate retention rate bounds (0-10000)
    if weekly_retention_rate > 10000 {
        return Err(crate::error::MiracleError::InvalidRetentionRate);
    }

    // Validate activity count bounds (reasonable bounds: 0-1M transactions per week)
    if weekly_activity_count > 1_000_000 {
        return Err(crate::error::MiracleError::InvalidActivityCount);
    }

    // Validate that weights are reasonable (not all zero)
    if user_weight == 0 && activity_weight == 0 && retention_weight == 0 {
        return Err(crate::error::MiracleError::InvalidWeights);
    }

    // Validate that weekly metrics are reasonable (not unreasonably large)
    if weekly_active_users > 1_000_000 {
        return Err(crate::error::MiracleError::InvalidInput);
    }

    Ok(())
}

/// Complete transparent calculation for customer rewards.
/// This function combines all steps of the reward calculation for transparency.
///
/// ## Formula Chain
/// 1. daily_rewards = calculate_daily_rewards(community_score, years_since_launch)
/// 2. customer_pool = daily_rewards * customer_reward_share / 10000
/// 3. customer_reward = (activity_count * customer_pool) / total_customer_activity
///
/// ## Parameters
/// - `activity_count`: Number of activities performed by the customer
/// - `community_score`: Community health score (0-10000 basis points)
/// - `years_since_launch`: Number of years since project launch (for time decay)
/// - `customer_reward_share`: Customer reward percentage in basis points (0-10000)
/// - `total_customer_activity`: Total activity count across all customers
///
/// ## Returns
/// - Individual customer reward amount in smallest token units
///
/// ## Usage
/// ```rust
/// use miracle_api::sdk::calculate_customer_reward_transparent;
///
/// let reward = calculate_customer_reward_transparent(
///     5,           // activity_count
///     8000,        // community_score
///     2,           // years_since_launch
///     7000,        // customer_reward_share
///     1000,        // total_customer_activity
/// );
/// println!("Reward: {} MIRACLE", reward);
/// ```
///
/// ## Note
/// This function provides complete transparency from community metrics to individual rewards.
/// It can be used both on-chain and off-chain for verification.
pub fn calculate_customer_reward_transparent(
    activity_count: u32,
    community_score: u16,
    years_since_launch: u32,
    customer_reward_share: u16,
    total_customer_activity: u32,
) -> u64 {
    crate::consts::calculate_customer_reward_transparent(
        activity_count,
        community_score,
        years_since_launch,
        customer_reward_share,
        total_customer_activity,
    )
}

/// Complete transparent calculation for customer rewards WITH activity capping.
/// This function matches the on-chain calculation behavior exactly.
///
/// ## Formula Chain
/// 1. daily_rewards = calculate_daily_rewards(community_score, years_since_launch)
/// 2. customer_pool = daily_rewards * customer_reward_share / 10000
/// 3. capped_activity = min(activity_count, max_customer_activity_per_epoch)
/// 4. customer_reward = (capped_activity * customer_pool) / total_customer_activity
///
/// ## Parameters
/// - `activity_count`: Number of activities performed by the customer
/// - `community_score`: Community health score (0-10000 basis points)
/// - `years_since_launch`: Number of years since project launch (for time decay)
/// - `customer_reward_share`: Customer reward percentage in basis points (0-10000)
/// - `total_customer_activity`: Total activity count across all customers
/// - `max_customer_activity_per_epoch`: Maximum allowed customer activity per epoch
///
/// ## Returns
/// - Individual customer reward amount in smallest token units (with activity capping)
///
/// ## Benefits
/// - Matches on-chain calculation exactly
/// - Includes activity capping to prevent gaming
/// - Complete transparency for off-chain estimation
/// - Deterministic calculation for verification
///
/// ## Usage
/// ```rust
/// use miracle_api::sdk::calculate_customer_reward_transparent_with_cap;
///
/// let reward = calculate_customer_reward_transparent_with_cap(
///     15,          // activity_count (will be capped)
///     8000,        // community_score
///     2,           // years_since_launch
///     7000,        // customer_reward_share
///     1000,        // total_customer_activity
///     10,          // max_customer_activity_per_epoch (caps activity at 10)
/// );
/// println!("Reward: {} MIRACLE", reward);
/// ```
///
/// ## Note
/// This function provides complete transparency from community metrics to individual rewards
/// and matches the on-chain calculation behavior exactly.
pub fn calculate_customer_reward_transparent_with_cap(
    activity_count: u32,
    community_score: u16,
    years_since_launch: u32,
    customer_reward_share: u16,
    total_customer_activity: u32,
    max_customer_activity_per_epoch: u32,
) -> u64 {
    crate::consts::calculate_customer_reward_transparent_with_cap(
        activity_count,
        community_score,
        years_since_launch,
        customer_reward_share,
        total_customer_activity,
        max_customer_activity_per_epoch,
    )
}

/// Complete transparent calculation for merchant rewards.
/// This function combines all steps of the reward calculation for transparency.
///
/// ## Formula Chain
/// 1. daily_rewards = calculate_daily_rewards(community_score, years_since_launch)
/// 2. merchant_pool = daily_rewards * merchant_reward_share / 10000
/// 3. merchant_reward = (activity_count * merchant_pool) / total_merchant_activity
///
/// ## Parameters
/// - `activity_count`: Number of activities performed by the merchant
/// - `community_score`: Community health score (0-10000 basis points)
/// - `years_since_launch`: Number of years since project launch (for time decay)
/// - `merchant_reward_share`: Merchant reward percentage in basis points (0-10000)
/// - `total_merchant_activity`: Total activity count across all merchants
///
/// ## Returns
/// - Individual merchant reward amount in smallest token units
///
/// ## Usage
/// ```rust
/// use miracle_api::sdk::calculate_merchant_reward_transparent;
///
/// let reward = calculate_merchant_reward_transparent(
///     3,           // activity_count
///     8000,        // community_score
///     2,           // years_since_launch
///     3000,        // merchant_reward_share
///     500,         // total_merchant_activity
/// );
/// println!("Reward: {} MIRACLE", reward);
/// ```
///
/// ## Note
/// This function provides complete transparency from community metrics to individual rewards.
/// It can be used both on-chain and off-chain for verification.
pub fn calculate_merchant_reward_transparent(
    activity_count: u32,
    community_score: u16,
    years_since_launch: u32,
    merchant_reward_share: u16,
    total_merchant_activity: u32,
) -> u64 {
    crate::consts::calculate_merchant_reward_transparent(
        activity_count,
        community_score,
        years_since_launch,
        merchant_reward_share,
        total_merchant_activity,
    )
}

/// Complete transparent calculation for merchant rewards WITH activity capping.
/// This function matches the on-chain calculation behavior exactly.
///
/// ## Formula Chain
/// 1. daily_rewards = calculate_daily_rewards(community_score, years_since_launch)
/// 2. merchant_pool = daily_rewards * merchant_reward_share / 10000
/// 3. capped_activity = min(activity_count, max_merchant_activity_per_epoch)
/// 4. merchant_reward = (capped_activity * merchant_pool) / total_merchant_activity
///
/// ## Parameters
/// - `activity_count`: Number of activities performed by the merchant
/// - `community_score`: Community health score (0-10000 basis points)
/// - `years_since_launch`: Number of years since project launch (for time decay)
/// - `merchant_reward_share`: Merchant reward percentage in basis points (0-10000)
/// - `total_merchant_activity`: Total activity count across all merchants
/// - `max_merchant_activity_per_epoch`: Maximum allowed merchant activity per epoch
///
/// ## Returns
/// - Individual merchant reward amount in smallest token units (with activity capping)
///
/// ## Benefits
/// - Matches on-chain calculation exactly
/// - Includes activity capping to prevent gaming
/// - Complete transparency for off-chain estimation
/// - Deterministic calculation for verification
///
/// ## Usage
/// ```rust
/// use miracle_api::sdk::calculate_merchant_reward_transparent_with_cap;
///
/// let reward = calculate_merchant_reward_transparent_with_cap(
///     25,          // activity_count (will be capped)
///     8000,        // community_score
///     2,           // years_since_launch
///     3000,        // merchant_reward_share
///     500,         // total_merchant_activity
///     20,          // max_merchant_activity_per_epoch (caps activity at 20)
/// );
/// println!("Reward: {} MIRACLE", reward);
/// ```
///
/// ## Note
/// This function provides complete transparency from community metrics to individual rewards
/// and matches the on-chain calculation behavior exactly.
pub fn calculate_merchant_reward_transparent_with_cap(
    activity_count: u32,
    community_score: u16,
    years_since_launch: u32,
    merchant_reward_share: u16,
    total_merchant_activity: u32,
    max_merchant_activity_per_epoch: u32,
) -> u64 {
    crate::consts::calculate_merchant_reward_transparent_with_cap(
        activity_count,
        community_score,
        years_since_launch,
        merchant_reward_share,
        total_merchant_activity,
        max_merchant_activity_per_epoch,
    )
}

/// Convert Unix timestamp to epoch number (day sequence since launch).
///
/// ## Formula
/// epoch = (timestamp - START_AT) / EPOCH_DURATION
///
/// ## Parameters
/// - `timestamp`: Unix timestamp in seconds
///
/// ## Returns
/// - Epoch number (0-based day sequence since launch)
///
/// ## Epoch Alignment
/// - Epoch 0: Sept 1, 2025 00:00:00 UTC to Sept 1, 2025 23:59:59 UTC
/// - Epoch 1: Sept 2, 2025 00:00:00 UTC to Sept 2, 2025 23:59:59 UTC
/// - Each epoch aligns with a natural UTC date (midnight to midnight)
/// - Project launches at START_AT (10:00 AM UTC on Sept 1, 2025) within epoch 0
///
/// ## Example
/// ```rust
/// use miracle_api::sdk;
/// let epoch = sdk::timestamp_to_epoch(1756756800); // Returns 0 (Sept 1, 2025 00:00:00 UTC)
/// let epoch = sdk::timestamp_to_epoch(1756843200); // Returns 1 (Sept 2, 2025 00:00:00 UTC)
/// ```
pub fn timestamp_to_epoch(timestamp: i64) -> u64 {
    // Align epochs with natural UTC dates (midnight to midnight)
    // Formula: Find the start of the UTC day containing START_AT
    // Then calculate epochs from that day boundary
    let start_day_beginning = (START_AT / EPOCH_DURATION) * EPOCH_DURATION; // Start of UTC day containing START_AT

    if timestamp < start_day_beginning {
        return 0; // Return epoch 0 for timestamps before the start of epoch 0
    }

    let adjusted_timestamp = timestamp - start_day_beginning;
    (adjusted_timestamp / EPOCH_DURATION) as u64
}

/// Calculate Unix timestamp from epoch number (day sequence).
///
/// ## Formula
/// timestamp = START_AT + (epoch * EPOCH_DURATION)
///
/// ## Parameters
/// - `epoch`: Epoch number (0-based day sequence since launch)
///
/// ## Returns
/// - Unix timestamp in seconds (start of the epoch day)
///
/// ## Epoch Alignment
/// - Epoch 0: Returns Sept 1, 2025 00:00:00 UTC
/// - Epoch 1: Returns Sept 2, 2025 00:00:00 UTC
/// - Each epoch starts at 00:00:00 UTC of the corresponding date
/// - Project launches at START_AT (10:00 AM UTC on Sept 1, 2025) within epoch 0
///
/// ## Example
/// ```rust
/// use miracle_api::sdk;
/// let timestamp = sdk::epoch_to_timestamp(0); // Returns 1756756800 (Sept 1, 2025 00:00:00 UTC)
/// let timestamp = sdk::epoch_to_timestamp(1); // Returns 1756843200 (Sept 2, 2025 00:00:00 UTC)
/// ```
pub fn epoch_to_timestamp(epoch: u64) -> i64 {
    // Align epochs with natural UTC dates (midnight to midnight)
    // Formula: Find the start of the UTC day containing START_AT
    // Then calculate timestamp from that day boundary
    let start_day_beginning = (START_AT / EPOCH_DURATION) * EPOCH_DURATION; // Start of UTC day containing START_AT
    start_day_beginning + (epoch as i64 * EPOCH_DURATION)
}

/// Convert a date range to a list of epochs.
///
/// ## Parameters
/// - `start_date`: Start date as Unix timestamp
/// - `end_date`: End date as Unix timestamp (inclusive)
///
/// ## Returns
/// - Vector of epoch numbers from start_date to end_date (inclusive)
///
/// ## Example
/// ```rust
/// use miracle_api::sdk;
/// let epochs = sdk::date_range_to_epochs(1756792800, 1756879199);
/// // Returns [0] for Sept 1, 2025 (launch day)
/// let epochs = sdk::date_range_to_epochs(1756792800, 1756965599);
/// // Returns [0, 1] for Sept 1-2, 2025
/// ```
pub fn date_range_to_epochs(start_date: i64, end_date: i64) -> Vec<u64> {
    if start_date > end_date {
        return Vec::new(); // Return empty vector for invalid range
    }

    let start_epoch = timestamp_to_epoch(start_date);
    let end_epoch = timestamp_to_epoch(end_date);

    (start_epoch..=end_epoch).collect()
}

/// Builds a batch claim instruction for a date range.
///
/// This function converts the date range to epochs and creates a vector claim.
/// It provides a user-friendly interface for claiming rewards across multiple days.
///
/// ## Parameters
/// - `signer`: The wallet signing the transaction
/// - `beneficiary`: The wallet receiving the rewards
/// - `start_date`: Start date as Unix timestamp
/// - `end_date`: End date as Unix timestamp (inclusive)
/// - `participant_type`: 0 = customer, 1 = merchant
/// - `max_batch_size`: Maximum epochs per batch (1-10)
/// - `merkle_proofs`: Vector of Merkle proof data for each epoch
///
/// ## Returns
/// - Instruction for batch claiming rewards across the date range
///
/// ## Note
/// - The date range is converted to epochs using `date_range_to_epochs`
/// - Each epoch requires its own Merkle proof in the `merkle_proofs` vector
/// - The number of proofs must match the number of epochs in the range
/// - If the date range is invalid or too large, returns an error
///
/// ## Example
/// ```rust
/// use miracle_api::sdk;
/// use solana_program::pubkey::Pubkey;
///
/// let signer = Pubkey::new_unique();
/// let beneficiary = Pubkey::new_unique();
/// let merkle_proofs = vec![vec![1, 2, 3], vec![4, 5, 6]]; // Example proofs
///
/// let instruction = sdk::batch_claim_date_range(
///     signer,
///     beneficiary,
///     1756792800, // Sept 1, 2025 00:00:00 UTC
///     1756879199, // Sept 1, 2025 23:59:59 UTC
///     0, // customer
///     10, // max batch size
///     merkle_proofs, // proofs for epoch 0
///     None, // social_data (no social claims)
/// );
/// ```
///
/// Batch claim instruction for date range - uses correct 8-account structure
pub fn batch_claim_date_range(
    signer: Pubkey,
    beneficiary: Pubkey,
    start_date: i64,
    end_date: i64,
    participant_type: u8,
    max_batch_size: u8,
    merkle_proofs: Vec<Vec<u8>>,
    social_data: Option<Vec<Option<SocialClaimData>>>,
) -> Result<Instruction, crate::error::MiracleError> {
    // Convert date range to epochs
    let epochs = date_range_to_epochs(start_date, end_date);

    if epochs.is_empty() {
        return Err(crate::error::MiracleError::InvalidInput);
    }

    if epochs.len() > max_batch_size as usize {
        return Err(crate::error::MiracleError::InvalidInput);
    }

    if merkle_proofs.len() != epochs.len() {
        return Err(crate::error::MiracleError::InvalidInput);
    }

    // Validate social_data if provided
    if let Some(ref social_data_vec) = social_data {
        if social_data_vec.len() != epochs.len() {
            return Err(crate::error::MiracleError::InvalidInput);
        }
    }

    // Create batch claim instruction using vector claim type
    let mut data = Vec::new();

    // Add instruction discriminator for MiracleInstruction::BatchClaim (value = 0)
    data.push(MiracleInstruction::BatchClaim as u8);

    // Manually serialize the BatchClaim struct fields in the exact order the program expects
    data.extend_from_slice(&[0u8; 8]); // start_epoch: 8 bytes (not used for date range)
    data.extend_from_slice(&[0u8; 8]); // end_epoch: 8 bytes (not used for date range)
    data.push(participant_type); // participant_type: 1 byte
    data.push(2u8); // claim_type: 1 byte (Date range claim = 2)
    data.push(epochs.len() as u8); // epoch_count: 1 byte
    data.push(max_batch_size); // max_batch_size: 1 byte
    data.extend_from_slice(&[0u8; 4]); // _padding: 4 bytes

    // Append epoch list
    for &epoch in &epochs {
        data.extend_from_slice(&epoch.to_le_bytes());
    }

    // Append Merkle proof data (consistent with single Claim)
    // For batch claims, we use the same merkle path and path indices for all epochs
    // since all epochs in a batch must use the same merkle root and structure
    let first_proof = &merkle_proofs[0];
    if first_proof.len() >= 37 {
        // Skip the first 33 bytes (merkle_root + merkle_path_length) and append the rest
        // This gives us: merkle_path + path_indices + activity_count
        data.extend_from_slice(&first_proof[33..]);
    } else {
        return Err(crate::error::MiracleError::InvalidInput);
    }

    // Append social flags (1 byte per epoch indicating if social claim exists)
    let social_flags = social_data
        .as_ref()
        .map(|social_vec| {
            social_vec
                .iter()
                .map(|opt| if opt.is_some() { 1u8 } else { 0u8 })
                .collect::<Vec<u8>>()
        })
        .unwrap_or_else(|| vec![0u8; epochs.len()]);

    data.extend_from_slice(&social_flags);

    // Append social data for epochs that have social claims
    if let Some(social_data_vec) = social_data {
        for social_opt in social_data_vec {
            if let Some(social) = social_opt {
                // Serialize SocialClaimData using bytemuck::bytes_of for consistent formatting
                data.extend_from_slice(bytemuck::bytes_of(&social));
            }
        }
    }

    // Create instruction with correct account structure matching program
    let proof_pda = proof_pda(signer);
    Ok(Instruction {
        program_id: crate::ID,
        accounts: vec![
            AccountMeta::new(signer, true),                     // [0] signer
            AccountMeta::new(beneficiary, false),               // [1] beneficiary
            AccountMeta::new(proof_pda.0, false),               // [2] proof PDA
            AccountMeta::new(TREASURY_ADDRESS, false),          // [3] treasury
            AccountMeta::new(TREASURY_TOKENS_ADDRESS, false),   // [4] treasury tokens
            AccountMeta::new_readonly(spl_token::ID, false),    // [5] token program
            AccountMeta::new_readonly(SNAPSHOT_ADDRESS, false), // [6] snapshot
            AccountMeta::new_readonly(CONFIG_ADDRESS, false),   // [7] config
        ],
        data,
    })
}

/// Builds a batch claim instruction for a vector of epochs.
///
/// This is the underlying function used by `batch_claim_date_range`.
/// Uses correct 8-account structure matching program.
/// It allows claiming rewards for specific epochs in a single transaction.
/// Supports both payment rewards and optional social rewards per epoch.
///
/// ## Parameters
/// - `signer`: The wallet signing the transaction
/// - `beneficiary`: The wallet receiving the rewards
/// - `epochs`: Vector of epoch numbers to claim
/// - `participant_type`: 0 for customer, 1 for merchant
/// - `max_batch_size`: Maximum epochs per batch (1-10)
/// - `epoch_proofs`: Vector of proof data for each epoch
/// - `social_data`: Optional vector of social data for each epoch (None = no social claim)
///
/// ## Returns
/// - Instruction for batch claiming rewards for specific epochs
///
/// ## Note
/// - Each epoch requires its own proof data
/// - The number of proofs must match the number of epochs
/// - Social data is optional per epoch (None = payment only, Some = payment + social)
/// - Epochs must be in ascending order for optimal gas efficiency
///
/// ## Data Structure
/// Each epoch proof contains:
/// - `DailyParticipantData`: Participant-specific information
/// - `Vec<[u8; 32]>`: Payment proof path
/// - `Vec<bool>`: Payment proof indices
/// - `Vec<[u8; 32]>`: Seal proof path
/// - `Vec<bool>`: Seal proof indices
/// - `[u8; 32]`: Payment root
/// - `EpochClaimData`: Epoch-specific reward and activity data
/// - `DailyParticipantData`: Participant data for each epoch
pub fn batch_claim_vector(
    signer: Pubkey,
    beneficiary: Pubkey,
    epochs: Vec<u64>,
    participant_type: u8,
    max_batch_size: u8,
    epoch_proofs: Vec<(
        Vec<[u8; 32]>, // payment_proof
        Vec<bool>,     // payment_indices
        Vec<[u8; 32]>, // seal_proof
        Vec<bool>,     // seal_indices
        [u8; 32],      // payment_root
        EpochClaimData,
        DailyParticipantData, // participant data for each epoch
    )>,
    social_data: Option<Vec<Option<SocialClaimData>>>,
) -> Result<Instruction, crate::error::MiracleError> {
    if epochs.is_empty() {
        return Err(crate::error::MiracleError::InvalidInput);
    }

    if epochs.len() > max_batch_size as usize {
        return Err(crate::error::MiracleError::InvalidInput);
    }

    if epoch_proofs.len() != epochs.len() {
        return Err(crate::error::MiracleError::InvalidInput);
    }

    // Validate social_data if provided
    if let Some(ref social_data_vec) = social_data {
        if social_data_vec.len() != epochs.len() {
            return Err(crate::error::MiracleError::InvalidInput);
        }
    }

    // Create batch claim instruction
    let mut data = Vec::new();

    // Use the BatchClaim struct's proper serialization like single claim does
    let batch_claim_data = BatchClaim {
        start_epoch: [0u8; 8], // Not used for vector claims
        end_epoch: [0u8; 8],   // Not used for vector claims
        participant_type,
        claim_type: 1u8, // Vector claim = 1
        epoch_count: epochs.len() as u8,
        max_batch_size,
        _padding: [0u8; 4],
    };
    data.extend_from_slice(&batch_claim_data.to_bytes());

    // Add epoch list with proper endianness like single claim
    for &epoch in &epochs {
        data.extend_from_slice(&epoch.to_le_bytes());
    }

    // Add proof data for each epoch
    for epoch_proof in &epoch_proofs {
        let (
            payment_proof,
            payment_indices,
            seal_proof,
            seal_indices,
            payment_root,
            epoch_data,
            participant_data,
        ) = epoch_proof;

        // Add payment proof length
        data.push(payment_proof.len() as u8);

        // Add payment proof path
        for path_node in payment_proof {
            data.extend_from_slice(path_node);
        }

        // Add payment indices
        for &is_right in payment_indices {
            data.push(if is_right { 1u8 } else { 0u8 });
        }

        // Add seal proof length
        data.push(seal_proof.len() as u8);

        // Add seal proof path
        for path_node in seal_proof {
            data.extend_from_slice(path_node);
        }

        // Add seal indices
        for &is_right in seal_indices {
            data.push(if is_right { 1u8 } else { 0u8 });
        }

        // Add payment root
        data.extend_from_slice(payment_root);

        // Add epoch data
        data.extend_from_slice(bytemuck::bytes_of(epoch_data));

        // Add participant data for this epoch
        data.extend_from_slice(bytemuck::bytes_of(participant_data));
    }

    // Add social flags (1 byte per epoch indicating if social claim exists)
    let social_flags = social_data
        .as_ref()
        .map(|social_vec| {
            social_vec
                .iter()
                .map(|opt| if opt.is_some() { 1u8 } else { 0u8 })
                .collect::<Vec<u8>>()
        })
        .unwrap_or_else(|| vec![0u8; epochs.len()]);

    data.extend_from_slice(&social_flags);

    // Add social data for epochs that have social claims
    if let Some(social_data_vec) = social_data {
        for social_opt in social_data_vec {
            if let Some(social) = social_opt {
                data.extend_from_slice(bytemuck::bytes_of(&social));
            }
        }
    }

    // Create instruction with correct account structure
    let proof_pda = proof_pda(signer);
    Ok(Instruction {
        program_id: crate::ID,
        accounts: vec![
            AccountMeta::new(signer, true),                     // [0] signer
            AccountMeta::new(beneficiary, false),               // [1] beneficiary
            AccountMeta::new(proof_pda.0, false),               // [2] proof PDA
            AccountMeta::new(TREASURY_ADDRESS, false),          // [3] treasury
            AccountMeta::new(TREASURY_TOKENS_ADDRESS, false),   // [4] treasury tokens
            AccountMeta::new_readonly(spl_token::ID, false),    // [5] token program
            AccountMeta::new_readonly(SNAPSHOT_ADDRESS, false), // [6] snapshot
            AccountMeta::new_readonly(CONFIG_ADDRESS, false),   // [7] config
        ],
        data,
    })
}

/// Build an UpdateTargets instruction to update community targets and activity limits.
/// This function allows the oracle to update configurable parameters based on community performance.
///
/// ## Parameters
/// - `oracle_authority`: The oracle authority that can update these parameters
/// - `target_weekly_users`: Target weekly active users (default: 500 for launch)
/// - `target_weekly_activity`: Target weekly activity count (default: 5,000 for launch)
/// - `target_retention_rate`: Target retention rate in basis points (default: 5,000 = 50%)
/// - `max_customer_activity_per_epoch`: Max customer activities per epoch (default: 5)
/// - `max_merchant_activity_per_epoch`: Max merchant activities per epoch (default: 50)
/// - `activity_cap_enabled`: Whether activity capping is enabled (default: 1 = enabled)
/// - `claim_cap_enabled`: Whether claim capping is enabled (default: 1 = enabled)
///
/// ## Returns
/// - Instruction to update community targets and activity limits
///
/// ## Authority
/// - Only the oracle authority can execute this instruction
/// - Oracle has the data to make informed decisions about community health
///
/// ## Benefits
/// - **Operational Flexibility**: Adjust parameters based on real community performance
/// - **Anti-Gaming**: Update activity limits to prevent new gaming strategies
/// - **Community Adaptation**: Adjust targets as community grows and evolves
/// - **Economic Balance**: Fine-tune parameters for sustainable tokenomics
/// - **Risk Management**: Adjust claim rewards threshold based on market conditions
///
/// ## Example
/// ```rust
/// use miracle_api::sdk;
/// use solana_program::pubkey::Pubkey;
///
/// let oracle_authority = Pubkey::new_unique();
/// let update_targets_ix = sdk::update_targets(
///     oracle_authority,
///     1000,   // target_weekly_users
///     10000,  // target_weekly_activity
///     6000,   // target_retention_rate (60%)
///     10,     // max_customer_activity_per_epoch
///     100,    // max_merchant_activity_per_epoch
///     1,      // activity_cap_enabled
///     1,      // claim_cap_enabled
///     1000000, // claim_rewards_threshold
/// );
/// ```
pub fn update_targets(
    oracle_authority: Pubkey,
    target_weekly_users: u32,
    target_weekly_activity: u32,
    target_retention_rate: u16,
    max_customer_activity_per_epoch: u32,
    max_merchant_activity_per_epoch: u32,
    activity_cap_enabled: u8,
    claim_cap_enabled: u8,
    claim_rewards_threshold: u64,
) -> Instruction {
    let data = UpdateTargets {
        target_weekly_users: target_weekly_users.to_le_bytes(),
        target_weekly_activity: target_weekly_activity.to_le_bytes(),
        target_retention_rate: target_retention_rate.to_le_bytes(),
        max_customer_activity_per_epoch: max_customer_activity_per_epoch.to_le_bytes(),
        max_merchant_activity_per_epoch: max_merchant_activity_per_epoch.to_le_bytes(),
        activity_cap_enabled,
        claim_cap_enabled,
        claim_rewards_threshold: claim_rewards_threshold.to_le_bytes(),
        _padding: [0; 4],
    }
    .to_bytes();

    Instruction {
        program_id: crate::ID,
        accounts: vec![
            AccountMeta::new(oracle_authority, true),
            AccountMeta::new(CONFIG_ADDRESS, false),
        ],
        data,
    }
}

// ===== MERKLE TREE CREATION MODULE =====

/// Merkle tree creation result containing the root and proof generation capabilities.
///
/// This structure provides everything needed for off-chain processors to:
/// 1. Generate the merkle root for snapshot updates
/// 2. Generate merkle proofs for individual claims
/// 3. Verify merkle proofs for validation
///
/// ## Security
/// - **Deterministic**: Same input data always produces the same merkle root
/// - **Cryptographic**: Uses Solana hashv for collision resistance
/// - **Efficient**: O(n) construction time, O(log n) proof generation
/// - **Verifiable**: All proofs can be verified on-chain
#[repr(C)]
#[derive(Clone, Debug, Serialize, Deserialize)]
pub struct MerkleTree {
    /// The merkle root hash (32 bytes) - used for snapshot updates
    pub root: [u8; 32],
    /// Internal tree structure for proof generation
    tree: Vec<Vec<[u8; 32]>>,
    /// Original participant data for proof generation
    participants: Vec<DailyParticipantData>,
}

impl MerkleTree {
    /// Create a new merkle tree from participant data.
    ///
    /// ## Parameters
    /// - `participants`: Vector of daily participant data
    ///
    /// ## Returns
    /// - `MerkleTree` instance with root and proof generation capabilities
    ///
    /// ## Panics
    /// - If participants vector is empty
    ///
    /// ## Example
    /// ```rust
    /// use miracle_api::{sdk, prelude::{DailyParticipantData, MerkleTree}};
    ///
    /// let participants = vec![
    ///     DailyParticipantData::new([1u8; 32], 1723680000, 1723766400, [1u8; 8], [2u8; 8], 5, 0),
    ///     DailyParticipantData::new([2u8; 32], 1723680000, 1723766400, [3u8; 8], [4u8; 8], 10, 1),
    /// ];
    ///
    /// let merkle_tree = MerkleTree::new(participants);
    /// println!("Merkle root: {:?}", merkle_tree.root());
    /// ```
    pub fn new(mut participants: Vec<DailyParticipantData>) -> Self {
        if participants.is_empty() {
            panic!("Cannot create merkle tree from empty participants list");
        }

        // Validate all participants
        for participant in &participants {
            participant.validate().expect("Invalid participant data");
        }

        // Sort participants deterministically by participant_id for consistent merkle tree construction
        // This ensures that the same participants always produce the same merkle root regardless of input order
        sort_participants_by_id(&mut participants);

        // Generate leaf hashes from sorted participants
        let mut leaves: Vec<[u8; 32]> =
            participants.iter().map(|p| p.compute_leaf_hash()).collect();

        // CRITICAL: Handle single leaf case - duplicate the leaf to force one hash operation
        // This matches Oracle's logic exactly for consistency
        if leaves.len() == 1 {
            leaves.push(leaves[0]); // Duplicate the single leaf
        }

        // Build merkle tree bottom-up
        let mut tree = vec![leaves.clone()];

        while leaves.len() > 1 {
            let mut new_level = Vec::new();
            for chunk in leaves.chunks(2) {
                if chunk.len() == 2 {
                    let combined = hashv(&[&chunk[0], &chunk[1]]).to_bytes();
                    new_level.push(combined);
                } else {
                    // Single element case - hash with itself for consistency
                    let combined = hashv(&[&chunk[0], &chunk[0]]).to_bytes();
                    new_level.push(combined);
                }
            }
            leaves = new_level;
            tree.push(leaves.clone());
        }

        println!("🔍 Debug: Built tree with {} levels", tree.len());
        for (i, level) in tree.iter().enumerate() {
            println!("🔍 Debug: Level {} has {} nodes", i, level.len());
        }

        let root = tree.last().unwrap()[0];
        println!("🔍 Debug: Root from tree: {:?}", root);
        println!("🔍 Debug: Root from leaves: {:?}", leaves[0]);

        Self {
            root,
            tree,
            participants,
        }
    }

    /// Get the merkle root hash.
    ///
    /// ## Returns
    /// - 32-byte merkle root hash for snapshot updates
    pub fn root(&self) -> [u8; 32] {
        self.root
    }

    /// Generate a merkle proof for a specific participant.
    ///
    /// ## Parameters
    /// - `participant_index`: Index of the participant in the original data
    ///
    /// ## Returns
    /// - `MerkleProof` containing path and indices for verification
    ///
    /// ## Panics
    /// - If participant_index is out of bounds
    ///
    /// ## Example
    /// ```rust
    /// use miracle_api::{sdk, prelude::{DailyParticipantData, MerkleTree, EpochClaimData}};
    /// use solana_program::pubkey::Pubkey;
    ///
    /// let participants = vec![
    ///     DailyParticipantData::new([1u8; 32], 1723680000, 1723766400, [1u8; 8], [2u8; 8], 5, 0),
    ///     DailyParticipantData::new([2u8; 32], 1723680000, 1723766400, [3u8; 8], [4u8; 8], 10, 1),
    /// ];
    ///
    /// let merkle_tree = MerkleTree::new(participants);
    /// let payment_proof = merkle_tree.generate_proof(0);
    /// let seal_proof = sdk::SealProof::new_for_verification(vec![[2u8; 32]], vec![true], merkle_tree.root());
    ///
    /// // Use proof for claim instruction using dual merkle tree
    /// let customer_wallet = Pubkey::new_unique();
    /// let beneficiary = Pubkey::new_unique();
    /// let epoch = 0u64;
    /// let participant_type = 0u8;
    /// let claim_ix = sdk::claim(
    ///     customer_wallet,
    ///     beneficiary,
    ///     epoch,
    ///     DailyParticipantData::new([1u8; 32], 1723680000, 1723766400, [1u8; 8], [2u8; 8], 5, 0),
    ///     payment_proof.path,
    ///     payment_proof.indices,
    ///     seal_proof.path,
    ///     seal_proof.indices,
    ///     seal_proof.payment_root,
    ///     EpochClaimData {
    ///         customer_reward_pool: 1000000u64.to_le_bytes(),
    ///         merchant_reward_pool: 500000u64.to_le_bytes(),
    ///         total_customer_activity: 0u64.to_le_bytes(),
    ///         total_merchant_activity: 0u64.to_le_bytes(),
    ///     },
    ///     participant_type,
    ///     None, // social_data (no social claim)
    /// );
    /// ```
    pub fn generate_proof(&self, participant_index: usize) -> MerkleProof {
        if participant_index >= self.participants.len() {
            panic!("Participant index out of bounds");
        }

        let mut path = Vec::new();
        let mut indices = Vec::new();
        let mut current_index = participant_index;

        println!(
            "🔍 Debug: Generating proof for participant index {}",
            participant_index
        );
        println!("🔍 Debug: Tree has {} levels", self.tree.len());

        // Traverse up the tree to build the proof
        for level in 0..self.tree.len() - 1 {
            let level_size = self.tree[level].len();
            println!(
                "🔍 Debug: Level {} has {} nodes, current_index = {}",
                level, level_size, current_index
            );

            if current_index % 2 == 0 {
                // Left child - need right sibling
                if current_index + 1 < level_size {
                    let sibling = self.tree[level][current_index + 1];
                    path.push(sibling);
                    indices.push(true); // true = sibling is on the right
                    println!(
                        "🔍 Debug: Level {}: Left child, adding right sibling {:?}",
                        level, sibling
                    );
                }
            } else {
                // Right child - need left sibling
                let sibling = self.tree[level][current_index - 1];
                path.push(sibling);
                indices.push(false); // false = sibling is on the left
                println!(
                    "🔍 Debug: Level {}: Right child, adding left sibling {:?}",
                    level, sibling
                );
            }

            current_index /= 2;
        }

        println!(
            "🔍 Debug: Generated proof with {} path nodes and indices {:?}",
            path.len(),
            indices
        );
        MerkleProof { path, indices }
    }

    /// Find participant by ID and generate proof.
    ///
    /// ## Parameters
    /// - `participant_id`: The participant ID to find
    ///
    /// ## Returns
    /// - `Some(MerkleProof)` if participant found
    /// - `None` if participant not found
    ///
    /// ## Example
    /// ```rust
    /// use miracle_api::{sdk, prelude::{DailyParticipantData, MerkleTree}};
    ///
    /// let participants = vec![
    ///     DailyParticipantData::new([1u8; 32], 1723680000, 1723766400, [1u8; 8], [2u8; 8], 5, 0),
    ///     DailyParticipantData::new([2u8; 32], 1723680000, 1723766400, [3u8; 8], [4u8; 8], 10, 1),
    /// ];
    ///
    /// let merkle_tree = MerkleTree::new(participants);
    ///
    /// if let Some(payment_proof) = merkle_tree.find_and_generate_proof([1u8; 32]) {
    ///     // Use payment proof for dual merkle tree claim
    /// }
    /// ```
    pub fn find_and_generate_proof(&self, participant_id: [u8; 32]) -> Option<MerkleProof> {
        self.participants
            .iter()
            .position(|p| p.participant_id == participant_id)
            .map(|index| self.generate_proof(index))
    }

    /// Get the number of participants in the tree.
    ///
    /// ## Returns
    /// - Number of participants
    pub fn participant_count(&self) -> usize {
        self.participants.len()
    }

    /// Get participant data by index.
    ///
    /// ## Parameters
    /// - `index`: Participant index
    ///
    /// ## Returns
    /// - `Some(&DailyParticipantData)` if index is valid
    /// - `None` if index is out of bounds
    pub fn get_participant(&self, index: usize) -> Option<&DailyParticipantData> {
        self.participants.get(index)
    }

    /// Get all participant data.
    ///
    /// ## Returns
    /// - Reference to all participant data
    pub fn participants(&self) -> &[DailyParticipantData] {
        &self.participants
    }
}

/// Merkle proof for a specific participant.
///
/// This structure contains the path and direction indices needed to verify
/// that a participant's data is included in the merkle tree.
///
/// ## Security
/// - **Cryptographic**: Uses Solana hashv for collision resistance
/// - **Deterministic**: Same participant always generates same proof
/// - **Verifiable**: Can be verified on-chain against merkle root
#[repr(C)]
#[derive(Clone, Debug, Serialize, Deserialize)]
pub struct MerkleProof {
    /// Merkle path nodes (sibling hashes)
    pub path: Vec<[u8; 32]>,
    /// Direction indices (false = left, true = right)
    pub indices: Vec<bool>,
}

/// Seal proof structure for dual merkle tree verification.
/// Contains both the merkle proof path and the payment root being proven.
/// Enhanced with epoch-specific data for accurate historical reward calculations.
#[repr(C)]
#[derive(Clone, Debug, Serialize, Deserialize)]
pub struct SealProof {
    /// Seal merkle path nodes (sibling hashes)
    pub path: Vec<[u8; 32]>,
    /// Seal direction indices (false = left, true = right)
    pub indices: Vec<bool>,
    /// Payment root being proven (embedded in seal proof)
    pub payment_root: [u8; 32],
    /// Epoch-specific reward calculation data for accurate historical calculations
    pub customer_reward_pool: u64,
    pub merchant_reward_pool: u64,
    pub total_customer_activity: u64,
    pub total_merchant_activity: u64,
    pub community_score: u16,
    pub customer_reward_share: u16,
    pub merchant_reward_share: u16,
    pub weekly_active_users: u32,
    pub weekly_retention_rate: u16,
    pub weekly_activity_count: u32,
}

impl MerkleProof {
    /// Create a new merkle proof.
    ///
    /// ## Parameters
    /// - `path`: Vector of merkle path nodes
    /// - `indices`: Vector of direction indices
    ///
    /// ## Returns
    /// - New MerkleProof instance
    pub fn new(path: Vec<[u8; 32]>, indices: Vec<bool>) -> Self {
        Self { path, indices }
    }

    /// Verify this proof against a merkle root and participant data.
    ///
    /// ## Parameters
    /// - `participant`: The participant data to verify
    /// - `merkle_root`: The expected merkle root
    ///
    /// ## Returns
    /// - `true` if proof is valid
    /// - `false` if proof is invalid
    ///
    /// ## Example
    /// ```rust
    /// use miracle_api::{sdk, prelude::{DailyParticipantData, MerkleTree}};
    ///
    /// let participant = DailyParticipantData::new([1u8; 32], 1723680000, 1723766400, [1u8; 8], [2u8; 8], 5, 0);
    /// let participants = vec![participant.clone()];
    /// let merkle_tree = MerkleTree::new(participants);
    /// let proof = merkle_tree.generate_proof(0);
    ///
    /// assert!(proof.verify(&participant, merkle_tree.root()));
    /// ```
    pub fn verify(&self, participant: &DailyParticipantData, merkle_root: [u8; 32]) -> bool {
        if self.path.len() != self.indices.len() {
            return false;
        }

        let mut current_hash = participant.compute_leaf_hash();
        println!(
            "🔍 Debug: Starting verification with leaf hash: {:?}",
            current_hash
        );

        // Traverse the proof path
        for (i, &path_node) in self.path.iter().enumerate() {
            let is_right = self.indices[i];
            println!(
                "🔍 Debug: Step {}: is_right={}, path_node={:?}",
                i, is_right, path_node
            );

            if is_right {
                // When is_right is true, the sibling is on the right
                // So current_hash should be on the left, path_node on the right
                // Use hashv(&[&left, &right]) to match tree construction
                current_hash = hashv(&[&current_hash, &path_node]).to_bytes();
            } else {
                // When is_right is false, the sibling is on the left
                // So path_node should be on the left, current_hash on the right
                // Use hashv(&[&left, &right]) to match tree construction
                current_hash = hashv(&[&path_node, &current_hash]).to_bytes();
            }
            println!("🔍 Debug: Step {}: current hash = {:?}", i, current_hash);
        }

        println!(
            "🔍 Debug: Final hash: {:?}, Expected root: {:?}",
            current_hash, merkle_root
        );
        current_hash == merkle_root
    }

    /// Get the proof length (number of path nodes).
    ///
    /// ## Returns
    /// - Number of nodes in the proof path
    pub fn length(&self) -> usize {
        self.path.len()
    }

    /// Check if this is an empty proof (single leaf tree).
    ///
    /// ## Returns
    /// - `true` if proof is empty
    /// - `false` if proof has path nodes
    pub fn is_empty(&self) -> bool {
        self.path.is_empty()
    }

    /// Serialize the MerkleProof to bytes (for use in transactions, batch claims, etc.)
    pub fn serialize(&self) -> Vec<u8> {
        bincode::serialize(self).expect("MerkleProof serialization failed")
    }

    /// Deserialize a MerkleProof from bytes.
    pub fn deserialize(data: &[u8]) -> Self {
        bincode::deserialize(data).expect("MerkleProof deserialization failed")
    }
}

/// Create a merkle tree from participant data.
///
/// This is a convenience function that creates a merkle tree from a vector
/// of participant data. It's the primary entry point for off-chain processors.
///
/// ## Parameters
/// - `participants`: Vector of daily participant data
///
/// ## Returns
/// - `MerkleTree` instance with root and proof generation capabilities
///
/// ## Panics
/// - If participants vector is empty
///
/// ## Example
/// ```rust
/// use miracle_api::{sdk, prelude::{DailyParticipantData, MerkleTree}};
///
/// // Off-chain processor aggregates daily payments
/// let participants = vec![
///     DailyParticipantData::new([1u8; 32], 1723680000, 1723766400, [1u8; 8], [2u8; 8], 5, 0),
///     DailyParticipantData::new([2u8; 32], 1723680000, 1723766400, [3u8; 8], [4u8; 8], 10, 1),
/// ];
///
/// // Create merkle tree
/// let merkle_tree = sdk::create_merkle_tree(participants);
/// println!("Merkle root: {:?}", merkle_tree.root());
/// ```
pub fn create_merkle_tree(participants: Vec<DailyParticipantData>) -> MerkleTree {
    MerkleTree::new(participants)
}

/// Verify a merkle proof against a merkle root and participant data.
///
/// This is a convenience function for proof verification that can be used
/// both off-chain (for testing) and on-chain (in claim instructions).
///
/// ## Parameters
/// - `participant`: The participant data to verify
/// - `proof`: The merkle proof
/// - `merkle_root`: The expected merkle root
///
/// ## Returns
/// - `true` if proof is valid
/// - `false` if proof is invalid
///
/// ## Example
/// ```rust
/// use miracle_api::{sdk, prelude::DailyParticipantData};
///
/// let participant = DailyParticipantData::new([1u8; 32], 1723680000, 1723766400, [1u8; 8], [2u8; 8], 5, 0);
/// let participants = vec![participant.clone()];
/// let merkle_tree = sdk::create_merkle_tree(participants);
/// let proof = merkle_tree.generate_proof(0);
///
/// assert!(sdk::verify_merkle_proof(&participant, &proof, merkle_tree.root()));
/// ```
pub fn verify_merkle_proof(
    participant: &DailyParticipantData,
    proof: &MerkleProof,
    merkle_root: [u8; 32],
) -> bool {
    proof.verify(participant, merkle_root)
}

/// Find the index of a participant in the participant list.
///
/// This helper function allows users to find their index in the Merkle tree
/// without needing to know the internal ordering. This is useful for:
/// - Generating proofs for claims
/// - Verifying participant inclusion
/// - Building user-friendly interfaces
///
/// ## Parameters
/// - `participants`: Vector of daily participant data
/// - `participant_id`: The participant ID to find
///
/// ## Returns
/// - `Some(index)` if participant found
/// - `None` if participant not found
///
/// ## Example
/// ```rust
/// use miracle_api::{sdk, prelude::{DailyParticipantData, MerkleTree, EpochClaimData}};
/// use solana_program::pubkey::Pubkey;
///
/// let participants = vec![
///     DailyParticipantData::new([1u8; 32], 1723680000, 1723766400, [1u8; 8], [2u8; 8], 5, 0),
///     DailyParticipantData::new([2u8; 32], 1723680000, 1723766400, [3u8; 8], [4u8; 8], 10, 1),
/// ];
///
/// let my_id = [1u8; 32];
/// if let Some(my_index) = sdk::find_participant_index(&participants, my_id) {
///     println!("My index in the Merkle tree: {}", my_index);
///     
///     // Generate proof using the index
///     let merkle_tree = sdk::create_merkle_tree(participants);
///     let proof = merkle_tree.generate_proof(my_index);
///     
///     // Use proof for claim
///     let customer_wallet = Pubkey::new_unique();
///     let beneficiary = Pubkey::new_unique();
///     let epoch = 0u64;
///     let activity_count = 5u32;
///     let participant_type = 0u8;
///     let payment_proof = merkle_tree.generate_proof(my_index);
///     let seal_proof = sdk::SealProof::new_for_verification(vec![[2u8; 32]], vec![true], merkle_tree.root());
///     let claim_ix = sdk::claim(
///         customer_wallet,
///         beneficiary,
///         epoch,
///         DailyParticipantData::new([1u8; 32], 1723680000, 1723766400, [1u8; 8], [2u8; 8], 5, 0),
///         payment_proof.path,
///         payment_proof.indices,
///         seal_proof.path,
///         seal_proof.indices,
///         seal_proof.payment_root,
///         EpochClaimData {
///             customer_reward_pool: 1000000u64.to_le_bytes(),
///             merchant_reward_pool: 500000u64.to_le_bytes(),
///             total_customer_activity: 0u64.to_le_bytes(),
///             total_merchant_activity: 0u64.to_le_bytes(),
///         },
///         participant_type,
///         None, // social_data (no social claim)
///     );
/// }
/// ```
///
/// ## Alternative Approaches
/// Instead of finding the index, you can also use:
/// ```rust
/// use miracle_api::{sdk, prelude::{DailyParticipantData, MerkleTree}};
///
/// let participants = vec![
///     DailyParticipantData::new([1u8; 32], 1723680000, 1723766400, [1u8; 8], [2u8; 8], 5, 0),
///     DailyParticipantData::new([2u8; 32], 1723680000, 1723766400, [3u8; 8], [4u8; 8], 10, 1),
/// ];
///
/// let my_id = [1u8; 32];
/// // Direct proof generation by participant ID
/// let merkle_tree = sdk::create_merkle_tree(participants);
/// if let Some(proof) = merkle_tree.find_and_generate_proof(my_id) {
///     // Use proof directly
/// }
/// ```
pub fn find_participant_index(
    participants: &[DailyParticipantData],
    participant_id: [u8; 32],
) -> Option<usize> {
    participants
        .iter()
        .position(|p| p.participant_id == participant_id)
}

/// Helper to sort participants deterministically by participant_id (lexicographically).
/// This is recommended for trustless Merkle tree construction.
pub fn sort_participants_by_id(participants: &mut [DailyParticipantData]) {
    participants.sort_by(|a, b| a.participant_id.cmp(&b.participant_id));
}

/// Convert wallet address to participant ID (32-byte hash).
///
/// This function creates a deterministic participant ID from a wallet address
/// by hashing the address bytes. This ensures consistent participant identification
/// across different systems while maintaining privacy.
///
/// ## Parameters
/// - `wallet_address`: Base58 encoded Solana wallet address
///
/// ## Returns
/// - 32-byte participant ID hash
///
/// ## Example
/// ```rust
/// use miracle_api::sdk;
///
/// let wallet = "9WzDXwBbmkg8ZTbNMqUxvQRAyrZzDsGYdLVL9zYtAWWM";
/// let participant_id = sdk::wallet_to_participant_id(wallet);
/// println!("Participant ID: {:?}", participant_id);
/// ```
///
/// ## Note
/// - Uses Solana's hashv function for deterministic results
/// - Same wallet address always produces same participant ID
/// - 32-byte output matches DailyParticipantData::participant_id type
/// - Matches on-chain participant ID computation exactly
pub fn wallet_to_participant_id(wallet_address: &str) -> [u8; 32] {
    use solana_program::pubkey::Pubkey;
    use std::str::FromStr;

    // Parse wallet address to Pubkey first, then hash the bytes (same as on-chain)
    match Pubkey::from_str(wallet_address) {
        Ok(pubkey) => {
            let wallet_bytes = pubkey.to_bytes();
            hashv(&[&wallet_bytes]).to_bytes()
        }
        Err(_) => {
            // Fallback to hash of string bytes if Pubkey parsing fails
            hashv(&[wallet_address.as_bytes()]).to_bytes()
        }
    }
}

/// Find participant by wallet address in a participant list.
///
/// This function converts the wallet address to a participant ID and then
/// searches for it in the participant list. Useful for user-friendly lookups
/// when you have the wallet address but need to find the participant data.
///
/// ## Parameters
/// - `participants`: Vector of daily participant data
/// - `wallet_address`: Base58 encoded Solana wallet address
///
/// ## Returns
/// - `Some(index)` if participant found
/// - `None` if participant not found
///
/// ## Example
/// ```rust
/// use miracle_api::{sdk, prelude::{DailyParticipantData, MerkleTree, EpochClaimData}};
/// use solana_program::pubkey::Pubkey;
///
/// let participants = vec![
///     DailyParticipantData::new([1u8; 32], 1723680000, 1723766400, [1u8; 8], [2u8; 8], 5, 0),
///     DailyParticipantData::new([2u8; 32], 1723680000, 1723766400, [3u8; 8], [4u8; 8], 10, 1),
/// ];
///
/// let wallet = "9WzDXwBbmkg8ZTbNMqUxvQRAyrZzDsGYdLVL9zYtAWWM";
/// if let Some(index) = sdk::find_participant_by_wallet(&participants, wallet) {
///     println!("Found participant at index: {}", index);
///     
///     // Generate proof using the index
///     let merkle_tree = sdk::create_merkle_tree(participants);
///     let proof = merkle_tree.generate_proof(index);
///     
///     // Use proof for claim
///     let customer_wallet = Pubkey::new_unique();
///     let beneficiary = Pubkey::new_unique();
///     let epoch = 0u64;
///     let activity_count = 5u32;
///     let participant_type = 0u8;
///     let payment_proof = merkle_tree.generate_proof(index);
///     let seal_proof = sdk::SealProof::new_for_verification(vec![[2u8; 32]], vec![true], merkle_tree.root());
///     let claim_ix = sdk::claim(
///         customer_wallet,
///         beneficiary,
///         epoch,
///         DailyParticipantData::new([1u8; 32], 1723680000, 1723766400, [1u8; 8], [2u8; 8], 5, 0),
///         payment_proof.path,
///         payment_proof.indices,
///         seal_proof.path,
///         seal_proof.indices,
///         seal_proof.payment_root,
///         EpochClaimData {
///             customer_reward_pool: 1000000u64.to_le_bytes(),
///             merchant_reward_pool: 500000u64.to_le_bytes(),
///             total_customer_activity: 0u64.to_le_bytes(),
///             total_merchant_activity: 0u64.to_le_bytes(),
///         },
///         participant_type,
///         None, // social_data (no social claim)
///     );
/// }
/// ```
pub fn find_participant_by_wallet(
    participants: &[DailyParticipantData],
    wallet_address: &str,
) -> Option<usize> {
    let participant_id = wallet_to_participant_id(wallet_address);
    participants
        .iter()
        .position(|p| p.participant_id == participant_id)
}

/// Create DailyParticipantData from wallet address and payment information.
///
/// This convenience function creates a DailyParticipantData instance from
/// a wallet address, automatically converting it to the required participant ID.
/// Useful for off-chain processors when aggregating payment data.
///
/// ## Parameters
/// - `wallet_address`: Base58 encoded Solana wallet address
/// - `first_payment_timestamp`: Unix timestamp of first payment
/// - `last_payment_timestamp`: Unix timestamp of last payment
/// - `first_payment_tx_sig_short`: First payment transaction signature (short)
/// - `last_payment_tx_sig_short`: Last payment transaction signature (short)
/// - `payment_count`: Number of transactions for this participant
/// - `participant_type`: 0 for customer, 1 for merchant
///
/// ## Returns
/// - New DailyParticipantData instance
///
/// ## Example
/// ```rust
/// use miracle_api::{sdk, prelude::{DailyParticipantData, MerkleTree}};
///
/// // Off-chain processor aggregating daily payments
/// let customer_wallet = "9WzDXwBbmkg8ZTbNMqUxvQRAyrZzDsGYdLVL9zYtAWWM";
/// let customer_data = sdk::create_participant_from_wallet(
///     customer_wallet,
///     1723680000,     // first payment timestamp
///     1723766400,     // last payment timestamp
///     [1u8; 8],       // first payment tx sig short
///     [2u8; 8],       // last payment tx sig short
///     5,              // 5 transactions
///     0,              // customer type
/// );
///
/// let merchant_wallet = "7xKXtg2CW87d97TXJSDpbD5jBkheTqA83TZRuJosgAsU";
/// let merchant_data = sdk::create_participant_from_wallet(
///     merchant_wallet,
///     1723680000,     // first payment timestamp
///     1723766400,     // last payment timestamp
///     [3u8; 8],       // first payment tx sig short
///     [4u8; 8],       // last payment tx sig short
///     10,             // 10 transactions
///     1,              // merchant type
/// );
///
/// // Create merkle tree from aggregated data
/// let participants = vec![customer_data, merchant_data];
/// let merkle_tree = sdk::create_merkle_tree(participants);
/// println!("Merkle root: {:?}", merkle_tree.root());
/// ```
pub fn create_participant_from_wallet(
    wallet_address: &str,
    first_payment_timestamp: i64,
    last_payment_timestamp: i64,
    first_payment_tx_sig_short: [u8; 8],
    last_payment_tx_sig_short: [u8; 8],
    payment_count: u32,
    participant_type: u8,
) -> DailyParticipantData {
    DailyParticipantData::new(
        wallet_to_participant_id(wallet_address),
        first_payment_timestamp,
        last_payment_timestamp,
        first_payment_tx_sig_short,
        last_payment_tx_sig_short,
        payment_count,
        participant_type,
    )
}

/// Generate merkle proof for a wallet address.
///
/// This convenience function combines wallet address lookup and proof generation.
/// It finds the participant by wallet address and generates their merkle proof
/// in one step. Useful for user-facing applications where you have the wallet
/// address but need the proof for claiming.
///
/// ## Parameters
/// - `participants`: Vector of daily participant data
/// - `wallet_address`: Base58 encoded Solana wallet address
///
/// ## Returns
/// - `Some(MerkleProof)` if participant found
/// - `None` if participant not found
///
/// ## Example
/// ```rust
/// use miracle_api::{sdk, prelude::{DailyParticipantData, MerkleTree, EpochClaimData}};
/// use solana_program::pubkey::Pubkey;
///
/// let participants = vec![
///     DailyParticipantData::new([1u8; 32], 1723680000, 1723766400, [1u8; 8], [2u8; 8], 5, 0),
///     DailyParticipantData::new([2u8; 32], 1723680000, 1723766400, [3u8; 8], [4u8; 8], 10, 1),
/// ];
///
/// let wallet = "9WzDXwBbmkg8ZTbNMqUxvQRAyrZzDsGYdLVL9zYtAWWM";
/// if let Some(proof) = sdk::generate_proof_for_wallet(&participants, wallet) {
///     println!("Generated proof with {} path nodes", proof.length());
///     
///     // Use proof for claim
///     let merkle_tree = sdk::create_merkle_tree(participants);
///     let customer_wallet = Pubkey::new_unique();
///     let beneficiary = Pubkey::new_unique();
///     let epoch = 0u64;
///     let activity_count = 5u32;
///     let participant_type = 0u8;
///     let payment_proof = proof;
///     let seal_proof = sdk::SealProof::new_for_verification(vec![[2u8; 32]], vec![true], merkle_tree.root());
///     let claim_ix = sdk::claim(
///         customer_wallet,
///         beneficiary,
///         epoch,
///         DailyParticipantData::new([1u8; 32], 1723680000, 1723766400, [1u8; 8], [2u8; 8], 5, 0),
///         payment_proof.path,
///         payment_proof.indices,
///         seal_proof.path,
///         seal_proof.indices,
///         seal_proof.payment_root,
///         EpochClaimData {
///             customer_reward_pool: 1000000u64.to_le_bytes(),
///             merchant_reward_pool: 500000u64.to_le_bytes(),
///             total_customer_activity: 0u64.to_le_bytes(),
///             total_merchant_activity: 0u64.to_le_bytes(),
///         },
///         participant_type,
///         None, // social_data (no social claim)
///     );
/// }
/// ```
pub fn generate_proof_for_wallet(
    participants: &[DailyParticipantData],
    wallet_address: &str,
) -> Option<MerkleProof> {
    let merkle_tree = create_merkle_tree(participants.to_vec());
    merkle_tree.find_and_generate_proof(wallet_to_participant_id(wallet_address))
}

// ===== CLAIMS TRACKING MODULE =====

/// Generate a unique claim key for tracking claims.
///
/// The claim key is a hash of participant ID, epoch, participant type, and claim type.
/// This ensures each claim is uniquely identifiable and prevents double-spending.
///
/// ## Parameters
/// - `participant_id`: 32-byte participant ID (wallet hash)
/// - `epoch`: Epoch number
/// - `participant_type`: 0 = customer, 1 = merchant
/// - `claim_type`: 1 = payment only, 3 = payment + social
///
/// ## Returns
/// - 32-byte claim key hash
///
/// ## Security
/// - **Unique**: Each (participant, epoch, type) combination has unique key
/// - **Collision Resistant**: Uses SHA-256 for cryptographic security
/// - **Deterministic**: Same inputs always produce same key
pub fn generate_claim_key(
    participant_id: [u8; 32],
    epoch: u64,
    participant_type: u8,
    claim_type: u8,
) -> [u8; 32] {
    use solana_program::hash::hashv;

    hashv(&[
        &participant_id,
        &epoch.to_le_bytes(),
        &participant_type.to_le_bytes(),
        &claim_type.to_le_bytes(),
    ])
    .to_bytes()
}

// ===== DUAL MERKLE TREE VERIFICATION FUNCTIONS =====

/// Verify a dual merkle claim using both payment and seal proofs.
///
/// This function implements the core security verification for the Dual Merkle Tree system.
/// It verifies both the payment merkle proof (user activity within epoch) and the seal
/// merkle proof (payment root authenticity from oracle), with the payment root embedded
/// in the seal proof data.
///
/// ## Parameters
/// - `payment_proof`: Merkle proof for user's activity within the epoch
/// - `seal_proof`: Merkle proof that payment root is in the seal tree (contains payment root)
/// - `on_chain_seal_root`: Current seal merkle root stored on-chain
/// - `participant_data`: User's participant data to verify
///
/// ## Returns
/// - `Ok(())` if both proofs are valid
/// - `Err(InvalidPaymentProof)` if payment proof is invalid
/// - `Err(InvalidSealProof)` if seal proof is invalid
///
/// ## Security Features
/// - **Payment Proof**: Ensures claim data integrity within an epoch
/// - **Seal Proof**: Ensures payment merkle root is authentic (from oracle)
/// - **Payment Root**: Embedded in seal proof for explicit verification
/// - **Dual Verification**: Both proofs must pass for a valid claim
///
/// ## Example
/// ```rust
/// use miracle_api::{sdk, prelude::{DailyParticipantData, MerkleProof, SealProof}};
///
/// let participant = DailyParticipantData::new([1u8; 32], 1723680000, 1723766400, [1u8; 8], [2u8; 8], 5, 0);
/// let payment_proof = MerkleProof::new(vec![[2u8; 32]], vec![true]);
/// let seal_proof = SealProof::new_for_verification(vec![[4u8; 32]], vec![false], [3u8; 32]);
/// let on_chain_seal_root = [5u8; 32];
///
/// let result = sdk::verify_dual_merkle_claim(
///     &payment_proof,
///     &seal_proof,
///     on_chain_seal_root,
///     &participant,
/// );
///
/// match result {
///     Ok(()) => println!("Dual merkle verification successful"),
///     Err(e) => println!("Verification failed: {:?}", e),
/// }
/// ```
pub fn verify_dual_merkle_claim(
    payment_proof: &MerkleProof,
    seal_proof: &SealProof,
    on_chain_seal_root: [u8; 32],
    participant_data: &DailyParticipantData,
) -> Result<(), crate::error::MiracleError> {
    // Rule 1: Verify seal proof - payment root must be in seal merkle tree
    if !verify_seal_proof(
        &seal_proof.path,
        &seal_proof.indices,
        seal_proof.payment_root,
        on_chain_seal_root,
    ) {
        return Err(crate::error::MiracleError::InvalidSealProof);
    }

    // Rule 2: Verify payment proof against payment root
    if !payment_proof.verify(participant_data, seal_proof.payment_root) {
        return Err(crate::error::MiracleError::InvalidPaymentProof);
    }

    Ok(())
}

impl SealProof {
    /// Create a new seal proof with path, indices, payment root, and epoch-specific data.
    ///
    /// This constructor is required for:
    /// - Historical reward calculations
    /// - Production claim verification
    /// - Accurate epoch-specific data
    ///
    /// Use this for all production claims that require historical accuracy.
    ///
    /// ## Parameters
    /// - `path`: Seal merkle path nodes (sibling hashes)
    /// - `indices`: Seal direction indices (false = left, true = right)
    /// - `payment_root`: Payment root being proven (embedded in seal proof)
    /// - `customer_reward_pool`: Epoch-specific customer reward pool
    /// - `merchant_reward_pool`: Epoch-specific merchant reward pool
    /// - `total_customer_activity`: Epoch-specific total customer activity
    /// - `total_merchant_activity`: Epoch-specific total merchant activity
    /// - `community_score`: Epoch-specific community score
    /// - `customer_reward_share`: Epoch-specific customer reward share
    /// - `merchant_reward_share`: Epoch-specific merchant reward share
    /// - `weekly_active_users`: Epoch-specific weekly active users
    /// - `weekly_retention_rate`: Epoch-specific weekly retention rate
    /// - `weekly_activity_count`: Epoch-specific weekly activity count
    pub fn new(
        path: Vec<[u8; 32]>,
        indices: Vec<bool>,
        payment_root: [u8; 32],
        customer_reward_pool: u64,
        merchant_reward_pool: u64,
        total_customer_activity: u64,
        total_merchant_activity: u64,
        community_score: u16,
        customer_reward_share: u16,
        merchant_reward_share: u16,
        weekly_active_users: u32,
        weekly_retention_rate: u16,
        weekly_activity_count: u32,
    ) -> Self {
        Self {
            path,
            indices,
            payment_root,
            customer_reward_pool,
            merchant_reward_pool,
            total_customer_activity,
            total_merchant_activity,
            community_score,
            customer_reward_share,
            merchant_reward_share,
            weekly_active_users,
            weekly_retention_rate,
            weekly_activity_count,
        }
    }

    /// Create a new seal proof for verification purposes only.
    ///
    /// This constructor is suitable for:
    /// - Proof verification (merkle path validation)
    /// - Testing and development
    /// - Backward compatibility with existing proofs
    /// - Client-side utility functions
    ///
    /// ⚠️  WARNING: This proof will have zero epoch data.
    /// For historical reward calculations, use oracle-generated proofs instead.
    ///
    /// ## Parameters
    /// - `path`: Seal merkle path nodes (sibling hashes)
    /// - `indices`: Seal direction indices (false = left, true = right)
    /// - `payment_root`: Payment root being proven (embedded in seal proof)
    ///
    /// ## Usage
    /// ```rust
    /// use miracle_api::prelude::SealProof;
    /// let path = vec![[1u8; 32], [2u8; 32]];
    /// let indices = vec![true, false];
    /// let payment_root = [3u8; 32];
    /// let proof = SealProof::new_for_verification(path, indices, payment_root);
    /// // Use for proof verification only
    /// ```
    pub fn new_for_verification(
        path: Vec<[u8; 32]>,
        indices: Vec<bool>,
        payment_root: [u8; 32],
    ) -> Self {
        Self {
            path,
            indices,
            payment_root,
            customer_reward_pool: 0,
            merchant_reward_pool: 0,
            total_customer_activity: 0,
            total_merchant_activity: 0,
            community_score: 0,
            customer_reward_share: 0,
            merchant_reward_share: 0,
            weekly_active_users: 0,
            weekly_retention_rate: 0,
            weekly_activity_count: 0,
        }
    }
}

/// Verify a seal merkle proof.
///
/// This function verifies that a payment merkle root is included in the seal merkle tree.
/// The seal proof demonstrates that the payment root is authentic and was provided by the oracle.
///
/// ## Parameters
/// - `seal_path`: Seal merkle path nodes (Vec<[u8; 32]>)
/// - `seal_indices`: Seal direction indices (Vec<bool>)
/// - `payment_root`: Payment merkle root to verify
/// - `seal_root`: Root of the seal merkle tree
///
/// ## Returns
/// - `true` if seal proof is valid
/// - `false` if seal proof is invalid
///
/// ## Security
/// - Verifies payment root is authentic (from oracle)
/// - Prevents forged payment roots
/// - Ensures payment root is in the historical seal tree
fn verify_seal_proof(
    seal_path: &Vec<[u8; 32]>,
    seal_indices: &Vec<bool>,
    payment_root: [u8; 32],
    seal_root: [u8; 32],
) -> bool {
    // REJECT empty seal proof paths - they can't be verified
    if seal_path.is_empty() {
        return false;
    }

    if seal_path.len() != seal_indices.len() {
        return false;
    }

    let mut current_hash = payment_root;

    // Traverse the seal proof path
    for (i, &path_node) in seal_path.iter().enumerate() {
        let is_right = seal_indices[i];

        let mut combined_data = Vec::new();
        if is_right {
            // When is_right is true, the sibling is on the right
            // So current_hash should be on the left, path_node on the right
            combined_data.extend_from_slice(&current_hash);
            combined_data.extend_from_slice(&path_node);
        } else {
            // When is_right is false, the sibling is on the left
            // So path_node should be on the left, current_hash on the right
            combined_data.extend_from_slice(&path_node);
            combined_data.extend_from_slice(&current_hash);
        }

        current_hash = hashv(&[&combined_data]).to_bytes();
    }

    current_hash == seal_root
}

/// Seal Merkle Tree for incremental construction of historical payment roots.
///
/// This tree grows incrementally, adding each new payment merkle root as a leaf.
/// It enables unlimited claim history while maintaining perfect security.
///
/// ## Growth Pattern
///
/// The seal tree grows incrementally:
/// - Epoch 0: [Payment Root 0]
/// - Epoch 1: [Payment Root 0] + [Payment Root 1] -> Seal Root 1
/// - Epoch 2: [Payment Root 0] + [Payment Root 1] + [Payment Root 2] -> Seal Root 2
/// - ...
/// - Epoch N: [Payment Root 0] + ... + [Payment Root N] -> Seal Root N
///
/// ## Security
/// - Each payment root is embedded in the seal tree
/// - Seal proofs demonstrate payment root authenticity
/// - Dual verification prevents all attack vectors
///
/// ## 🚨 CRITICAL: Chronological Ordering Requirement
///
/// **PAYMENT ROOTS MUST BE PROVIDED IN CHRONOLOGICAL ORDER (EPOCH 0, 1, 2, 3...)**
///
/// This is essential for:
/// - Deterministic seal merkle root generation
/// - Consistent verification between Oracle and on-chain program
/// - Preventing `0x10` (InvalidPaymentProof) errors
///
/// The Oracle team MUST ensure:
/// 1. Database queries return epochs in chronological order
/// 2. Payment roots are collected in epoch sequence
/// 3. `SealMerkleTree::from_payment_roots()` receives ordered data
///
/// Failure to maintain chronological ordering will result in:
/// - Different seal merkle roots between Oracle and on-chain
/// - Proof verification failures
/// - Inability to process claims
#[repr(C)]
#[derive(Clone, Debug, Serialize, Deserialize)]
pub struct SealMerkleTree {
    /// Current seal merkle root (32 bytes)
    pub root: [u8; 32],
    /// Internal tree structure for proof generation
    tree: Vec<Vec<[u8; 32]>>,
    /// Historical payment roots (leaves of the seal tree)
    payment_roots: Vec<[u8; 32]>,
}

impl SealMerkleTree {
    /// Create a new empty seal merkle tree.
    ///
    /// ## Returns
    /// - Empty seal merkle tree with zero root
    pub fn new() -> Self {
        Self {
            root: [0u8; 32],
            tree: vec![vec![]],
            payment_roots: vec![],
        }
    }

    /// Create a seal merkle tree from existing payment roots.
    ///
    /// ## Parameters
    /// - `payment_roots`: Vector of historical payment merkle roots
    ///
    /// ## Returns
    /// - Seal merkle tree with all payment roots included
    ///
    /// ## Important: Chronological Ordering
    /// The payment roots MUST be provided in chronological order (epoch 0, 1, 2, 3...)
    /// to ensure deterministic and verifiable seal merkle roots across all systems.
    /// This ordering rule is enforced to maintain consistency between Oracle and on-chain verification.
    pub fn from_payment_roots(payment_roots: Vec<[u8; 32]>) -> Self {
        if payment_roots.is_empty() {
            return Self::new();
        }

        // CRITICAL: Enforce chronological ordering for deterministic seal merkle roots
        // The Oracle team must provide payment roots in epoch order (0, 1, 2, 3...)
        // This ensures the on-chain program can verify proofs against the same tree structure
        if payment_roots.len() > 1 {
            // Note: We cannot directly sort by epoch number from payment root hashes
            // The Oracle team MUST provide payment roots in chronological order (0, 1, 2, 3...)
            // This is a critical architectural requirement for deterministic tree construction

            // Log warning about chronological ordering requirement
            // This helps debug ordering issues during development
            println!(
                "⚠️  WARNING: SealMerkleTree::from_payment_roots called with {} payment roots",
                payment_roots.len()
            );
            println!("   CRITICAL: Oracle team MUST provide payment roots in chronological order (epoch 0, 1, 2, 3...)");
            println!("   This ensures deterministic seal merkle roots for on-chain verification");
            println!("   Current implementation assumes correct ordering from Oracle team");
        }

        // Build merkle tree from payment roots
        let mut tree = Vec::new();
        tree.push(payment_roots.clone());

        while tree.last().unwrap().len() > 1 {
            let current_level = tree.last().unwrap();
            let mut next_level = Vec::new();

            for chunk in current_level.chunks(2) {
                if chunk.len() == 2 {
                    // Correct hash ordering: left child first, then right child
                    let combined = hashv(&[&chunk[0], &chunk[1]]).to_bytes();
                    next_level.push(combined);
                } else {
                    // Single element case
                    let combined = hashv(&[&chunk[0], &chunk[0]]).to_bytes();
                    next_level.push(combined);
                }
            }

            tree.push(next_level);
        }

        let root = tree.last().unwrap()[0];

        Self {
            root,
            tree,
            payment_roots,
        }
    }

    /// Add a new payment root to the seal merkle tree.
    ///
    /// This function incrementally grows the seal tree by adding the new payment root
    /// and rebuilding the tree structure.
    ///
    /// ## Parameters
    /// - `payment_root`: New payment merkle root to add
    ///
    /// ## Returns
    /// - Updated seal merkle tree with new payment root included
    ///
    /// ## Important: Chronological Ordering
    /// Payment roots MUST be added in chronological order (epoch 0, 1, 2, 3...)
    /// to maintain deterministic tree structure. This method assumes the new payment root
    /// is for the next sequential epoch.
    pub fn add_payment_root(&mut self, payment_root: [u8; 32]) {
        // CRITICAL: Ensure payment roots are added in chronological order
        // This method assumes the new payment root is for the next sequential epoch
        // The Oracle team must call this method in epoch order to maintain consistency
        println!(
            "🔒 Adding payment root to seal merkle tree (epoch {})",
            self.payment_roots.len()
        );
        println!("   CRITICAL: Payment roots must be added in chronological order for deterministic verification");

        self.payment_roots.push(payment_root);

        // Rebuild the entire tree with the new payment root
        let mut tree = Vec::new();
        tree.push(self.payment_roots.clone());

        while tree.last().unwrap().len() > 1 {
            let current_level = tree.last().unwrap();
            let mut next_level = Vec::new();

            for chunk in current_level.chunks(2) {
                if chunk.len() == 2 {
                    // Correct hash ordering: left child first, then right child
                    let combined = hashv(&[&chunk[0], &chunk[1]]).to_bytes();
                    next_level.push(combined);
                } else {
                    // Single element case
                    let combined = hashv(&[&chunk[0], &chunk[0]]).to_bytes();
                    next_level.push(combined);
                }
            }

            tree.push(next_level);
        }

        self.tree = tree;
        self.root = self.tree.last().unwrap()[0];
    }

    /// Get the current seal merkle root.
    ///
    /// ## Returns
    /// - Current seal merkle root (32 bytes)
    pub fn root(&self) -> [u8; 32] {
        self.root
    }

    /// Get the number of payment roots in the seal tree.
    ///
    /// ## Returns
    /// - Number of historical payment roots
    pub fn payment_root_count(&self) -> usize {
        self.payment_roots.len()
    }

    /// Get all payment roots in the seal tree.
    ///
    /// ## Returns
    /// - Vector of all historical payment roots
    pub fn payment_roots(&self) -> &[[u8; 32]] {
        &self.payment_roots
    }

    /// Validate that payment roots are in chronological order.
    ///
    /// This method helps ensure the Oracle team is providing payment roots
    /// in the correct epoch sequence for deterministic tree construction.
    ///
    /// ## Returns
    /// - `true` if payment roots appear to be in chronological order
    /// - `false` if there are potential ordering issues
    ///
    /// ## Note
    /// This is a best-effort validation since we can't directly determine
    /// epoch numbers from payment root hashes. The Oracle team must ensure
    /// chronological ordering when calling this method.
    pub fn validate_chronological_order(&self) -> bool {
        if self.payment_roots.len() <= 1 {
            return true; // Single or no payment roots are always "ordered"
        }

        // Log the current payment root count for debugging
        println!(
            "🔍 Validating chronological order of {} payment roots",
            self.payment_roots.len()
        );
        println!("   CRITICAL: Oracle team must ensure payment roots are provided in epoch order (0, 1, 2, 3...)");

        // Since we can't directly validate epoch numbers from hashes,
        // we rely on the Oracle team's commitment to chronological ordering
        // This method serves as a reminder and debugging aid
        true
    }

    /// Generate a seal proof for a specific payment root.
    ///
    /// This function creates a proof that demonstrates a payment root is included
    /// in the current seal merkle tree.
    ///
    /// ## Parameters
    /// - `payment_root`: Payment root to generate proof for
    ///
    /// ## Returns
    /// - `Some(SealProof)` if payment root is found
    /// - `None` if payment root is not in the tree
    pub fn generate_seal_proof(&self, payment_root: [u8; 32]) -> Option<SealProof> {
        // Find the index of the payment root
        let payment_root_index = self
            .payment_roots
            .iter()
            .position(|&root| root == payment_root)?;

        let mut path = Vec::new();
        let mut indices = Vec::new();

        let mut current_index = payment_root_index;
        for level in &self.tree[..self.tree.len() - 1] {
            let sibling_index = if current_index % 2 == 0 {
                current_index + 1
            } else {
                current_index - 1
            };

            if sibling_index < level.len() {
                path.push(level[sibling_index]);
                indices.push(current_index % 2 == 1); // true if right sibling
            }

            current_index /= 2;
        }

        Some(SealProof::new_for_verification(path, indices, payment_root))
    }

    /// Find and generate a seal proof for a payment root by epoch.
    ///
    /// This is a convenience function that finds a payment root by its epoch index
    /// and generates a seal proof for it.
    ///
    /// ## Parameters
    /// - `epoch_index`: Index of the epoch (0-based)
    ///
    /// ## Returns
    /// - `Some(SealProof)` if epoch exists
    /// - `None` if epoch index is out of bounds
    pub fn generate_seal_proof_for_epoch(&self, epoch_index: usize) -> Option<SealProof> {
        let payment_root = self.payment_roots.get(epoch_index)?;
        self.generate_seal_proof(*payment_root)
    }

    /// Verify that a payment root is included in the seal tree.
    ///
    /// ## Parameters
    /// - `payment_root`: Payment root to verify
    ///
    /// ## Returns
    /// - `true` if payment root is in the seal tree
    /// - `false` if payment root is not in the seal tree
    pub fn contains_payment_root(&self, payment_root: [u8; 32]) -> bool {
        self.payment_roots.contains(&payment_root)
    }
}

/// Create a new seal merkle tree.
///
/// This is a convenience function that creates an empty seal merkle tree.
/// Use `SealMerkleTree::from_payment_roots()` to create a tree with existing payment roots.
///
/// ## Returns
/// - Empty seal merkle tree
///
/// ## Example
/// ```rust
/// use miracle_api::sdk::create_seal_merkle_tree;
///
/// let mut seal_tree = create_seal_merkle_tree();
/// seal_tree.add_payment_root([1u8; 32]);
/// println!("Seal root: {:?}", seal_tree.root());
/// ```
pub fn create_seal_merkle_tree() -> SealMerkleTree {
    SealMerkleTree::new()
}

/// Create a seal merkle tree from payment roots.
///
/// This is a convenience function that creates a seal merkle tree from existing payment roots.
///
/// ## Parameters
/// - `payment_roots`: Vector of historical payment merkle roots
///
/// ## Returns
/// - Seal merkle tree with all payment roots included
///
/// ## 🚨 CRITICAL: Chronological Ordering Requirement
///
/// **PAYMENT ROOTS MUST BE PROVIDED IN CHRONOLOGICAL ORDER (EPOCH 0, 1, 2, 3...)**
///
/// This is essential for deterministic seal merkle root generation and consistent
/// verification between Oracle and on-chain program. Failure to maintain chronological
/// ordering will result in proof verification failures.
///
/// ## Example
/// ```rust
/// use miracle_api::sdk::create_seal_merkle_tree_from_roots;
///
/// let payment_roots = vec![[1u8; 32], [2u8; 32], [3u8; 32]];
/// let seal_tree = create_seal_merkle_tree_from_roots(payment_roots);
/// println!("Seal root: {:?}", seal_tree.root());
/// ```
pub fn create_seal_merkle_tree_from_roots(payment_roots: Vec<[u8; 32]>) -> SealMerkleTree {
    SealMerkleTree::from_payment_roots(payment_roots)
}

/// Generate a seal proof for a payment root.
///
/// This is a convenience function that generates a seal proof for a payment root
/// from a seal merkle tree.
///
/// ## Parameters
/// - `seal_tree`: Seal merkle tree
/// - `payment_root`: Payment root to generate proof for
///
/// ## Returns
/// - `Some(SealProof)` if payment root is found
/// - `None` if payment root is not in the tree
///
/// ## Example
/// ```rust
/// use miracle_api::sdk::{create_seal_merkle_tree_from_roots, generate_seal_proof};
///
/// let payment_roots = vec![[1u8; 32], [2u8; 32]];
/// let seal_tree = create_seal_merkle_tree_from_roots(payment_roots);
/// let seal_proof = generate_seal_proof(&seal_tree, [1u8; 32]);
/// assert!(seal_proof.is_some());
/// ```
pub fn generate_seal_proof(
    seal_tree: &SealMerkleTree,
    payment_root: [u8; 32],
) -> Option<SealProof> {
    seal_tree.generate_seal_proof(payment_root)
}

/// Computes the epoch hash for the Epoch Hash Chain security solution.
///
/// This function implements the same logic as the on-chain program:
/// - Epoch 0: Uses the predefined genesis hash constant
/// - Subsequent epochs: Hash(previous_epoch_hash + epoch_number + current_payment_merkle_root)
///
/// ## Parameters
/// - `epoch`: The epoch number
/// - `previous_epoch_hash`: The hash from the previous epoch (use genesis hash for epoch 0)
/// - `payment_merkle_root`: The current epoch's payment merkle root
///
/// ## Returns
/// The computed epoch hash for tamper detection
///
/// ## Security
/// This function must be used consistently between off-chain oracle processing
/// and on-chain verification to maintain the hash chain integrity.
/// The epoch number inclusion ensures uniqueness even with identical payment roots.
///
/// ## Implementation Details
/// - **Epoch 0**: Uses the predefined genesis hash constant (same as on-chain program)
/// - **Subsequent epochs**: Build upon the previous epoch hash + epoch number + payment root
/// - **No fallback logic**: Since program now initializes with genesis hash, fallback is not needed
/// - **Uniqueness guarantee**: Epoch number ensures uniqueness even with identical payment roots
pub fn compute_epoch_hash(
    epoch: u64,
    previous_epoch_hash: [u8; 32],
    payment_merkle_root: [u8; 32],
) -> [u8; 32] {
    if epoch == 0 {
        // For epoch 0, use the predefined genesis hash constant
        // This maintains security while allowing epoch 0 to be properly initialized
        crate::consts::miracle_epoch_0_genesis()
    } else {
        // For subsequent epochs: Previous hash + EPOCH_NUMBER + current payment merkle root
        // This creates an unbreakable chain: each epoch depends on all previous epochs
        // The epoch number ensures uniqueness even when payment roots are identical (e.g., empty epochs)

        // Handle fallback for backward compatibility (external callers might still pass [0; 32])
        let previous_epoch_hash = if previous_epoch_hash == [0u8; 32] {
            // If previous epoch hash is zero, use genesis as fallback (same as program)
            // This handles cases where the previous epoch hash hasn't been set yet
            crate::consts::miracle_epoch_0_genesis()
        } else {
            previous_epoch_hash
        };

        // Include epoch number to ensure uniqueness even with empty payment roots
        let epoch_bytes = epoch.to_le_bytes();
        hashv(&[&previous_epoch_hash, &epoch_bytes, &payment_merkle_root]).to_bytes()
    }
}