Rust

Creating a Rust-based smart contract for Solana to achieve these functionalities involves building a program on Solana that defines the logic for a DAO fundraising process, token trading, and fund expiration mechanics. The contract will also incorporate logic to handle fundraising failure or success scenarios, as well as the curve-based AMM (automated market maker) for token trading. Here’s a high-level outline of how to structure this contract:

use anchor_lang::prelude::*;

use anchor_spl::token::{Token, TokenAccount, Mint, MintTo, Transfer, Burn};

declare_id!("YourProgramIdHere");

#[program]

pub mod dao_fundraise {

    use super::*;

    pub fn initialize(ctx: Context<Initialize>, fundraise_amount: u64, duration: i64) -> Result<()> {

        let fund = &mut ctx.accounts.fund;

        fund.creator = *ctx.accounts.creator.key;

        fund.fundraise_goal = fundraise_amount;

        fund.fundraise_end_time = Clock::get()?.unix_timestamp + duration;

        fund.state = FundState::Fundraising;

        Ok(())

    }

    pub fn contribute(ctx: Context<Contribute>, amount: u64) -> Result<()> {

        let fund = &mut ctx.accounts.fund;

        require!(Clock::get()?.unix_timestamp < fund.fundraise_end_time, ErrorCode::FundraiseEnded);

        require!(fund.state == FundState::Fundraising, ErrorCode::FundNotInFundraising);

        

        // Transfer SOL from contributor to fund

        token::transfer(ctx.accounts.transfer_ctx().with_signer(&[]), amount)?;

        fund.total_raised += amount;

        if fund.total_raised >= fund.fundraise_goal {

            fund.state = FundState::Successful;

        }

        Ok(())

    }

    pub fn finalize_fundraise(ctx: Context<FinalizeFundraise>) -> Result<()> {

        let fund = &mut ctx.accounts.fund;

        require!(Clock::get()?.unix_timestamp >= fund.fundraise_end_time, ErrorCode::FundraiseNotEnded);

        if fund.total_raised >= fund.fundraise_goal {

            fund.state = FundState::Successful;

        } else {

            fund.state = FundState::Failed;

        }

        Ok(())

    }

    pub fn invest(ctx: Context<Invest>, amount: u64) -> Result<()> {

        let fund = &mut ctx.accounts.fund;

        require!(fund.state == FundState::Successful, ErrorCode::FundNotSuccessful);

        

        // Placeholder for investment logic on Solana protocols

        // Implement specific logic to call protocol functions here

        fund.invested_amount += amount;

        Ok(())

    }

    pub fn sell(ctx: Context<Sell>, amount: u64) -> Result<()> {

        let fund = &mut ctx.accounts.fund;

        require!(fund.state == FundState::Successful, ErrorCode::FundNotSuccessful);

        

        // Logic to calculate current token price based on curve

        let price = calculate_price(fund.total_raised, fund.market_cap);

        

        // Burn user's DAO tokens

        token::burn(ctx.accounts.burn_ctx().with_signer(&[]), amount)?;

        // Transfer SOL back to seller based on price

        let sol_to_transfer = amount * price;

        token::transfer(ctx.accounts.transfer_ctx().with_signer(&[]), sol_to_transfer)?;

        Ok(())

    }

    pub fn redeem(ctx: Context<Redeem>) -> Result<()> {

        let fund = &mut ctx.accounts.fund;

        require!(fund.state == FundState::Successful, ErrorCode::FundNotSuccessful);

        

        // Calculate redeemable amount based on profits

        let redeemable_amount = calculate_redeemable(fund.total_raised, fund.invested_amount, fund.profit);

        // Transfer SOL to token holder

        token::transfer(ctx.accounts.transfer_ctx().with_signer(&[]), redeemable_amount)?;

        

        Ok(())

    }

}

#[derive(Accounts)]

pub struct Initialize<'info> {

    #[account(init, payer = creator, space = 8 + 128)]

    pub fund: Account<'info, Fund>,

    #[account(mut)]

    pub creator: Signer<'info>,

    pub system_program: Program<'info, System>,

}

#[derive(Accounts)]

pub struct Contribute<'info> {

    #[account(mut)]

    pub fund: Account<'info, Fund>,

    #[account(mut)]

    pub contributor: Signer<'info>,

    #[account(mut)]

    pub contributor_token_account: Account<'info, TokenAccount>,

    pub token_program: Program<'info, Token>,

}

#[derive(Accounts)]

pub struct FinalizeFundraise<'info> {

    #[account(mut, has_one = creator)]

    pub fund: Account<'info, Fund>,

    pub creator: Signer<'info>,

}

#[derive(Accounts)]

pub struct Invest<'info> {

    #[account(mut, has_one = creator)]

    pub fund: Account<'info, Fund>,

    pub creator: Signer<'info>,

}

#[derive(Accounts)]

pub struct Sell<'info> {

    #[account(mut)]

    pub fund: Account<'info, Fund>,

    #[account(mut)]

    pub seller: Signer<'info>,

    #[account(mut)]

    pub seller_token_account: Account<'info, TokenAccount>,

    pub token_program: Program<'info, Token>,

}

#[derive(Accounts)]

pub struct Redeem<'info> {

    #[account(mut)]

    pub fund: Account<'info, Fund>,

    #[account(mut)]

    pub redeemer: Signer<'info>,

    #[account(mut)]

    pub redeemer_token_account: Account<'info, TokenAccount>,

    pub token_program: Program<'info, Token>,

}

#[account]

pub struct Fund {

    pub creator: Pubkey,

    pub fundraise_goal: u64,

    pub total_raised: u64,

    pub invested_amount: u64,

    pub profit: u64,

    pub market_cap: u64,

    pub fundraise_end_time: i64,

    pub state: FundState,

}

#[derive(AnchorSerialize, AnchorDeserialize, Clone, PartialEq, Eq)]

pub enum FundState {

    Fundraising,

    Successful,

    Failed,

    Expired,

}

#[error_code]

pub enum ErrorCode {

    #[msg("Fundraising has already ended.")]

    FundraiseEnded,

    #[msg("The fund is not in fundraising state.")]

    FundNotInFundraising,

    #[msg("Fundraising is not over yet.")]

    FundraiseNotEnded,

    #[msg("The fund has not been successful.")]

    FundNotSuccessful,

}

fn calculate_price(total_raised: u64, market_cap: u64) -> u64 {

    // Placeholder for pricing algorithm based on market activity and fund's performance

    // Implement curve-based price calculation

    1

}

fn calculate_redeemable(total_raised: u64, invested_amount: u64, profit: u64) -> u64 {

    // Placeholder for redeemable logic calculation

    // Adjust based on the profits and investment return

    profit

}

Explanation of Functions and Key Logic

1. initialize: Starts a fundraising round with a goal and duration. Sets the fund’s state to fundraising.

2. contribute: Allows users to contribute SOL toward the fund. If contributions exceed the fundraising goal, the fund transitions to a successful state.

3. finalize_fundraise: Ends the fundraising round. If the goal is met, it becomes successful; otherwise, it fails.

4. invest: Manages the fund’s SOL investments in protocols if the fundraising is successful.

5. sell: Allows users to sell their tokens if the market cap is above the original goal.

6. redeem: Handles profit distribution to token holders at fund expiration.

Curve-Based Price Calculation

The price calculation and AMM functions (calculate_price and calculate_redeemable) are placeholders and should be implemented based on the preferred bonding curve and specific pricing model.

This structure can be modified to integrate with Solana-specific DeFi protocols, with careful security checks and testing for handling funds and token mechanics effectively.