1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
//! Transaction Bakery

use crate::error::{Error, Result};
use crate::metadata::TransactionMetadata;
use crate::time::time_range_into_slots;
use crate::wallet::Wallet;
use anyhow::anyhow;
use chain_query::{ChainQuery, EraSummary, Network, ProtocolParameters};
use chrono::{DateTime, Utc};
use itertools::Itertools;
use num_bigint::BigInt;
use plutus_ledger_api::csl::{lib as csl, pla_to_csl::TryToCSL};
use plutus_ledger_api::plutus_data::IsPlutusData;
use plutus_ledger_api::v2::address::{Address, AddressWithExtraInfo, Credential};
use plutus_ledger_api::v2::crypto::PaymentPubKeyHash;
use plutus_ledger_api::v2::datum::{Datum, DatumHash, OutputDatum};
use plutus_ledger_api::v2::redeemer::{Redeemer, RedeemerWithExtraInfo};
use plutus_ledger_api::v2::script::{MintingPolicyHash, ScriptHash, ValidatorHash};
use plutus_ledger_api::v2::transaction::{
    ScriptPurpose, TransactionHash, TransactionInfo, TransactionInput, TransactionOutput,
    TransactionOutputWithExtraInfo, TxInInfo,
};
use plutus_ledger_api::v2::value::{CurrencySymbol, Value};
use std::collections::BTreeMap;
use submitter::Submitter;
use tracing::{debug, info};
use utils::script::ScriptOrRef;

pub mod chain_query;
#[cfg(feature = "clap")]
pub mod clap;
pub mod error;
pub mod metadata;
pub mod submitter;
pub mod time;
pub mod tx_info_builder;
pub mod utils;
pub mod wallet;

/// Transaction builder
///
/// The purpose of this component is to convert a raw TransactionInfo (dough)
/// into a fully baked valid transaction.
/// TxBakery does not perform IO and won't change it's internal state once initialized.
pub struct TxBakery {
    config: csl::TransactionBuilderConfig,
    data_cost: csl::DataCost,
    cost_models: csl::Costmdls,
    system_start: DateTime<Utc>,
    era_summaries: Vec<EraSummary>,
    network_id: u8,
}

/// TransactionInfo with additional context required to build a valid transaction
#[derive(Clone, Debug)]
pub struct TxWithCtx<'a> {
    pub tx_info: &'a TransactionInfo,
    pub scripts: &'a BTreeMap<ScriptHash, ScriptOrRef>,
    pub collateral_strategy: &'a CollateralStrategy,
    pub change_strategy: &'a ChangeStrategy,
    pub metadata: Option<&'a TransactionMetadata>,
    pub ex_units_map: Option<&'a BTreeMap<(csl::RedeemerTag, csl::BigNum), csl::ExUnits>>,
}

/// Options to deal with change outputs and collateral returns
#[derive(Clone, Debug)]
pub enum ChangeStrategy {
    /// Send all change to an address
    Address(Address),
    /// Use the last output of the TransactionInfo as change output (modify it's value)
    /// Collateral returns are following the address of the last output
    LastOutput,
}

impl<'a> TxWithCtx<'a> {
    pub fn new(
        tx_info: &'a TransactionInfo,
        scripts: &'a BTreeMap<ScriptHash, ScriptOrRef>,
        collateral_strategy: &'a CollateralStrategy,
        change_strategy: &'a ChangeStrategy,
    ) -> Self {
        TxWithCtx {
            tx_info,
            scripts,
            collateral_strategy,
            change_strategy,
            metadata: None,
            ex_units_map: None,
        }
    }

    /// Attach transaction metadata to the context
    pub fn with_metadata(mut self, metadata: &'a TransactionMetadata) -> Self {
        self.metadata = Some(metadata);
        self
    }

    /// Explicitly add execution units instead of running the ChainQuery evaluation
    pub fn with_ex_units(
        mut self,
        ex_units_map: &'a BTreeMap<(csl::RedeemerTag, csl::BigNum), csl::ExUnits>,
    ) -> Self {
        self.ex_units_map = Some(ex_units_map);
        self
    }
}

/// Options to deal with collateral selection
#[derive(Clone, Debug)]
pub enum CollateralStrategy {
    /// Automatically pick a suitable UTxO from the transaction inputs
    Automatic {
        min_amount: u64,
        max_utxo_count: usize,
    },
    /// Explicitly set a UTxO (doesn't have to be an input UTxO)
    Explicit {
        utxos: Vec<TxInInfo>,
        min_amount: u64,
    },
    /// No collateral (for transaction without scripts)
    None,
}

impl TxBakery {
    /// Query all the parameters required to build a transaction and store it for later use.
    /// This command will call the ChainQuery service to pull certain chain parameters
    pub async fn init(chain_query: &impl ChainQuery) -> Result<Self> {
        debug!("Initialising Transaction Bakery");
        let protocol_params = chain_query.query_protocol_params().await?;
        let system_start = chain_query.query_system_start().await?;
        let era_summaries = chain_query.query_era_summaries().await?;
        let network = chain_query.get_network();

        Self::init_with_config(&network, &protocol_params, system_start, era_summaries).await
    }

    /// Init TxBakey with the required configurations
    /// This allows to directly inject configurations, and handle them separately from the bakery
    /// (for example prefetch and cache them)
    pub async fn init_with_config(
        network: &Network,
        protocol_params: &ProtocolParameters,
        system_start: DateTime<Utc>,
        era_summaries: Vec<EraSummary>,
    ) -> Result<Self> {
        let data_cost =
            csl::DataCost::new_coins_per_byte(&protocol_params.min_utxo_deposit_coefficient);

        let linear_fee = &csl::LinearFee::new(
            &protocol_params.min_fee_coefficient,
            &protocol_params.min_fee_constant,
        );
        let config = csl::TransactionBuilderConfigBuilder::new()
            .fee_algo(linear_fee)
            .pool_deposit(&protocol_params.stake_pool_deposit)
            .key_deposit(&protocol_params.stake_credential_deposit)
            .max_value_size(protocol_params.max_value_size.ok_or(
                Error::MissingProtocolParameter("max_value_size".to_string()),
            )?)
            .max_tx_size(protocol_params.max_transaction_size.ok_or(
                Error::MissingProtocolParameter("max_transaction_size".to_string()),
            )?)
            .coins_per_utxo_byte(&protocol_params.min_utxo_deposit_coefficient)
            .ex_unit_prices(&protocol_params.script_execution_prices.clone().ok_or(
                Error::MissingProtocolParameter("script_execution_prices".to_string()),
            )?)
            .prefer_pure_change(true);

        let config = match protocol_params.min_fee_reference_scripts {
            None => config,
            Some(ref unit_interval) => config.ref_script_coins_per_byte(unit_interval),
        }
        .build()
        .unwrap();

        Ok(TxBakery {
            config,
            data_cost,
            cost_models: protocol_params
                .plutus_cost_models
                .clone()
                .ok_or(Error::MissingProtocolParameter("cost_models".to_string()))?,
            system_start,
            era_summaries,
            network_id: network.to_network_id(),
        })
    }

    /// Create a new CSL transaction builder
    fn create_tx_builder(&self) -> csl::TransactionBuilder {
        csl::TransactionBuilder::new(&self.config)
    }

    /// Convert PLA TransactionInfo inputs, redeemers and datums to a CSL transaction input builder
    fn mk_inputs(
        &self,
        inputs: &[TxInInfo],
        ref_inputs: &[TxInInfo],
        input_redeemers: &BTreeMap<TransactionInput, Redeemer>,
        input_datums: &BTreeMap<DatumHash, Datum>,
        scripts: &BTreeMap<ScriptHash, ScriptOrRef>,
        ex_units_map: Option<&BTreeMap<(csl::RedeemerTag, csl::BigNum), csl::ExUnits>>,
    ) -> Result<csl::TxInputsBuilder> {
        let mut tx_inputs_builder = csl::TxInputsBuilder::new();

        inputs
            .iter()
            .enumerate()
            .try_for_each(|(idx, TxInInfo { reference, output })| {
                let redeemer = input_redeemers.get(reference);

                match redeemer {
                    None => {
                        tx_inputs_builder
                            .add_regular_input(
                                &AddressWithExtraInfo {
                                    address: &output.address,
                                    network_tag: self.network_id,
                                }
                                .try_to_csl()?,
                                &reference.try_to_csl()?,
                                &output.value.try_to_csl()?,
                            )
                            .map_err(|err| {
                                Error::TransactionBuildError(anyhow!(
                                    "Failed to add regular input {:?}: {}",
                                    reference,
                                    err
                                ))
                            })?;
                        Ok::<(), Error>(())
                    }
                    Some(redeemer) => {
                        let script_hash = match &output.address.credential {
                            Credential::Script(ValidatorHash(script_hash)) => Ok(script_hash),
                            _ => Err(Error::Internal(anyhow!(
                                "A public key transaction input should not have a redeemer."
                            ))),
                        }?;
                        let script_or_ref = scripts
                            .get(script_hash)
                            .ok_or_else(|| Error::MissingScript(script_hash.clone()))?;

                        let csl_redeemer = RedeemerWithExtraInfo {
                            redeemer,
                            tag: &csl::RedeemerTag::new_spend(),
                            index: idx as u64,
                        }
                        .try_to_csl()?;

                        let csl_redeemer = match ex_units_map {
                            Some(ex_units_map) => {
                                Self::apply_ex_units(&csl_redeemer, ex_units_map)?
                            }
                            None => csl_redeemer,
                        };

                        let script_source = match &script_or_ref {
                            ScriptOrRef::PlutusScript(script) => {
                                csl::PlutusScriptSource::new(script)
                            }
                            ScriptOrRef::RefScript(ref_tx_in, script) => {
                                ref_inputs
                                    .iter()
                                    .any(|TxInInfo { reference, .. }| reference == ref_tx_in)
                                    .then_some(())
                                    .ok_or_else(|| {
                                        Error::MissingReferenceScript(
                                            ref_tx_in.clone(),
                                            script_or_ref.get_script_hash(),
                                        )
                                    })?;
                                csl::PlutusScriptSource::new_ref_input(
                                    &script_hash.try_to_csl()?,
                                    &ref_tx_in.try_to_csl()?,
                                    &script.language_version(),
                                    script_or_ref.get_script_size(),
                                )
                            }
                        };

                        let datum_source = match &output.datum {
                            OutputDatum::DatumHash(dh) => {
                                let Datum(input_datum) = input_datums
                                    .get(dh)
                                    .ok_or(Error::MissingDatum(dh.clone()))?;

                                Some(csl::DatumSource::new(&input_datum.try_to_csl()?))
                            }

                            OutputDatum::InlineDatum(Datum(input_datum)) => {
                                Some(match &script_or_ref {
                                    ScriptOrRef::PlutusScript(_) => {
                                        csl::DatumSource::new(&input_datum.try_to_csl()?)
                                    }

                                    ScriptOrRef::RefScript(tx_in, _) => {
                                        csl::DatumSource::new_ref_input(&tx_in.try_to_csl()?)
                                    }
                                })
                            }

                            OutputDatum::None => None,
                        };

                        let tx_input_witness = match datum_source {
                            Some(datum_source) => csl::PlutusWitness::new_with_ref(
                                &script_source,
                                &datum_source,
                                &csl_redeemer,
                            ),
                            None => csl::PlutusWitness::new_with_ref_without_datum(
                                &script_source,
                                &csl_redeemer,
                            ),
                        };

                        tx_inputs_builder.add_plutus_script_input(
                            &tx_input_witness,
                            &reference.try_to_csl()?,
                            &output.value.try_to_csl()?,
                        );

                        Ok(())
                    }
                }
            })?;

        Ok(tx_inputs_builder)
    }

    /// Add transaction outputs to the builder
    /// If the change strategy if LastOutput, then we are postponing the addition of this output
    /// to balancing
    fn mk_outputs(
        &self,
        outputs: &Vec<TransactionOutput>,
        change_strategy: &ChangeStrategy,
        scripts: &BTreeMap<ScriptHash, ScriptOrRef>,
    ) -> Result<Vec<csl::TransactionOutput>> {
        let normal_outputs = match change_strategy {
            ChangeStrategy::Address(_) => outputs.as_slice(),
            ChangeStrategy::LastOutput => &outputs[..(outputs.len() - 1)],
        };
        let scripts = &scripts
            .iter()
            .map(|(hash, script)| (hash.clone(), script.clone().get_script()))
            .collect();
        Ok(normal_outputs
            .iter()
            .map(|transaction_output| {
                TransactionOutputWithExtraInfo {
                    scripts,
                    network_id: self.network_id,
                    data_cost: &self.data_cost,
                    transaction_output,
                }
                .try_to_csl()
            })
            .collect::<std::result::Result<_, _>>()?)
    }

    /// Convert PLA mints to CSL and pair them with their corresponding redeemers
    fn mk_mints(
        tx_mint: &Value,
        ref_inputs: &[TxInInfo],
        mint_redeemers: &BTreeMap<ScriptHash, Redeemer>,
        scripts: &BTreeMap<ScriptHash, ScriptOrRef>,
        ex_units_map: Option<&BTreeMap<(csl::RedeemerTag, csl::BigNum), csl::ExUnits>>,
    ) -> Result<csl::MintBuilder> {
        let mut mint_builder = csl::MintBuilder::new();
        tx_mint
            .0
            .iter()
            .filter_map(|(cur_sym, assets)| match cur_sym {
                CurrencySymbol::NativeToken(MintingPolicyHash(script_hash)) => {
                    Some((script_hash, assets))
                }
                CurrencySymbol::Ada => None,
            })
            .enumerate()
            .try_for_each(|(idx, (script_hash, assets))| {
                assets.iter().try_for_each(|(token_name, amount)| {
                    let script_or_ref = scripts
                        .get(script_hash)
                        .ok_or(Error::MissingScript(script_hash.clone()))?;
                    let redeemer = mint_redeemers
                        .get(script_hash)
                        .ok_or(Error::MissingMintRedeemer(script_hash.clone()))?;

                    let csl_redeemer = RedeemerWithExtraInfo {
                        redeemer,
                        tag: &csl::RedeemerTag::new_mint(),
                        index: idx as u64,
                    }
                    .try_to_csl()?;

                    let csl_redeemer = match ex_units_map {
                        Some(ex_units_map) => Self::apply_ex_units(&csl_redeemer, ex_units_map)?,
                        None => csl_redeemer,
                    };

                    let script_source = match &script_or_ref {
                        ScriptOrRef::PlutusScript(script) => csl::PlutusScriptSource::new(script),
                        ScriptOrRef::RefScript(ref_tx_in, script) => {
                            ref_inputs
                                .iter()
                                .find(|TxInInfo { reference, .. }| reference == ref_tx_in)
                                .map(|_| ())
                                .ok_or_else(|| {
                                    Error::MissingReferenceScript(
                                        ref_tx_in.clone(),
                                        script_or_ref.get_script_hash(),
                                    )
                                })?;
                            csl::PlutusScriptSource::new_ref_input(
                                &script_hash.try_to_csl()?,
                                &ref_tx_in.try_to_csl()?,
                                &script.language_version(),
                                script_or_ref.get_script_size(),
                            )
                        }
                    };

                    let mint_witness =
                        csl::MintWitness::new_plutus_script(&script_source, &csl_redeemer);
                    mint_builder
                        .add_asset(
                            &mint_witness,
                            &token_name.try_to_csl()?,
                            &amount.try_to_csl()?,
                        )
                        .map_err(|err| {
                            Error::TransactionBuildError(anyhow!(
                                "Failed to add mint {:?}: {}",
                                MintingPolicyHash(script_hash.clone()),
                                err
                            ))
                        })?;
                    Ok::<(), Error>(())
                })
            })?;

        Ok(mint_builder)
    }

    /// Find suitable UTxOs to be used as a collateral. Each UTxO has to be at a pub key address,
    /// and the total Ada amount of must be at least the configured collateral amount
    // TODO(szg251): we could calculate the exact minimum collateral amount using protocol params
    fn find_collaterals(
        &self,
        min_collateral_amount: u64,
        max_utxo_count: usize,

        tx_inputs: &[TxInInfo],
    ) -> Result<Vec<TxInInfo>> {
        let min_collateral_amount = BigInt::from(min_collateral_amount);
        let (amount, collaterals) = tx_inputs
            .iter()
            .sorted_by_key(|input| -input.output.value.get_ada_amount())
            .take(max_utxo_count)
            .fold(
                (BigInt::ZERO, Vec::new()),
                |(mut acc_amount, mut collaterals), tx_in_info| {
                    if acc_amount < min_collateral_amount {
                        if let Credential::PubKey(_) = tx_in_info.output.address.credential {
                            let ada_amount = tx_in_info.output.value.get_ada_amount();
                            acc_amount += ada_amount;
                            collaterals.push(tx_in_info.clone());
                        }
                    };

                    (acc_amount, collaterals)
                },
            );

        if amount >= min_collateral_amount {
            Ok(collaterals)
        } else {
            Err(Error::NotEnoughCollaterals {
                amount,
                required: min_collateral_amount,
                utxos: collaterals,
            })
        }
    }

    fn mk_collaterals(&self, tx_inputs: &[TxInInfo]) -> Result<csl::TxInputsBuilder> {
        let mut tx_inputs_builder = csl::TxInputsBuilder::new();
        for tx_input in tx_inputs {
            let TxInInfo { reference, output } = tx_input;

            tx_inputs_builder
                .add_regular_input(
                    &output
                        .address
                        .with_extra_info(self.network_id)
                        .try_to_csl()?,
                    &reference.try_to_csl()?,
                    &output.value.try_to_csl()?,
                )
                .map_err(|err| {
                    Error::TransactionBuildError(anyhow!(
                        "Failed to add regular input {:?}: {}",
                        reference,
                        err
                    ))
                })?;
        }

        Ok(tx_inputs_builder)
    }

    /// Convert a PLA TransactionInfo into a CSL transaction builder.
    /// The result is not yet balanced and witnesses are not added. This is useful for
    /// some further manual processing of the transaction before finalising.
    pub fn mk_tx_builder(&self, tx: &TxWithCtx<'_>) -> Result<csl::TransactionBuilder> {
        let mut tx_builder = self.create_tx_builder();

        let (input_redeemers, mint_redeemers) = tx.tx_info.redeemers.0.iter().fold(
            (BTreeMap::new(), BTreeMap::new()),
            |(mut input_reds, mut mint_reds), (purpose, red)| {
                match purpose {
                    ScriptPurpose::Spending(tx_in) => {
                        input_reds.insert(tx_in.clone(), red.clone());
                    }
                    ScriptPurpose::Minting(CurrencySymbol::NativeToken(MintingPolicyHash(
                        script_hash,
                    ))) => {
                        mint_reds.insert(script_hash.clone(), red.clone());
                    }

                    _ => {}
                };
                (input_reds, mint_reds)
            },
        );

        let input_datums = tx
            .tx_info
            .datums
            .0
            .iter()
            .cloned()
            .collect::<BTreeMap<_, _>>();

        tx_builder.set_inputs(&self.mk_inputs(
            &tx.tx_info.inputs,
            &tx.tx_info.reference_inputs,
            &input_redeemers,
            &input_datums,
            tx.scripts,
            tx.ex_units_map,
        )?);

        tx.tx_info
            .reference_inputs
            .iter()
            .try_for_each(|TxInInfo { reference, output }| {
                match output.reference_script {
                    None => tx_builder.add_reference_input(&reference.try_to_csl()?),
                    Some(ref script_hash) => {
                        let script_or_ref = tx
                            .scripts
                            .get(script_hash)
                            .ok_or(Error::MissingScript(script_hash.clone()))?;
                        tx_builder.add_script_reference_input(
                            &reference.try_to_csl()?,
                            script_or_ref.get_script_size(),
                        )
                    }
                }
                Ok::<(), Error>(())
            })?;

        tx_builder.set_mint_builder(&TxBakery::mk_mints(
            &tx.tx_info.mint,
            &tx.tx_info.reference_inputs,
            &mint_redeemers,
            tx.scripts,
            tx.ex_units_map,
        )?);

        let collateral_return_address = match tx.change_strategy {
            ChangeStrategy::Address(addr) => addr,
            ChangeStrategy::LastOutput => {
                &tx.tx_info
                    .outputs
                    .last()
                    .ok_or(Error::MissingChangeOutput)?
                    .address
            }
        };

        match &tx.collateral_strategy {
            CollateralStrategy::Automatic {
                min_amount,
                max_utxo_count,
            } => {
                let tx_input =
                    self.find_collaterals(*min_amount, *max_utxo_count, &tx.tx_info.inputs)?;
                let collateral = self.mk_collaterals(&tx_input)?;
                tx_builder.set_collateral(&collateral);
                tx_builder
                    .set_total_collateral_and_return(
                        &csl::BigNum::from(*min_amount),
                        &collateral_return_address
                            .with_extra_info(self.network_id)
                            .try_to_csl()?,
                    )
                    .map_err(|source| Error::TransactionBuildError(anyhow!(source)))?;
            }
            CollateralStrategy::Explicit { utxos, min_amount } => {
                let collateral = self.mk_collaterals(utxos)?;
                tx_builder.set_collateral(&collateral);
                tx_builder
                    .set_total_collateral_and_return(
                        &csl::BigNum::from(*min_amount),
                        &collateral_return_address
                            .with_extra_info(self.network_id)
                            .try_to_csl()?,
                    )
                    .map_err(|source| Error::TransactionBuildError(anyhow!(source)))?;
            }
            CollateralStrategy::None => {}
        };

        self.mk_outputs(&tx.tx_info.outputs, tx.change_strategy, tx.scripts)?
            .iter()
            .try_for_each(|tx_out| {
                tx_builder
                    .add_output(tx_out)
                    .map_err(|source| Error::TransactionBuildError(anyhow!(source)))
            })?;

        let (validity_start, ttl) = time_range_into_slots(
            &self.era_summaries,
            &self.system_start,
            tx.tx_info.valid_range.clone(),
        )?;

        if let Some(validity_start) = validity_start {
            tx_builder.set_validity_start_interval_bignum(validity_start);
        }
        if let Some(ttl) = ttl {
            tx_builder.set_ttl_bignum(&ttl);
        }

        tx.tx_info
            .signatories
            .iter()
            .try_for_each(|PaymentPubKeyHash(pkh)| {
                tx_builder.add_required_signer(&pkh.try_to_csl()?);
                Ok::<(), Error>(())
            })?;

        if let Some(metadata) = tx.metadata {
            tx_builder.set_metadata(&metadata.try_into()?);
        }

        Ok(tx_builder)
    }

    pub fn mk_tx_body(&self, tx: &TxWithCtx<'_>) -> Result<csl::TransactionBody> {
        let tx_builder = self.mk_tx_builder(tx)?;

        let (datums, redeemers) = TxBakery::extract_witnesses(tx.tx_info)?;

        self.balance_transaction(tx, tx_builder, &datums, &redeemers)
    }

    /// Extract witness datums and redeemers from TransactionInfo
    /// Inline datums are embedded in the transaction body, so they won't appear here
    /// Redeemers execution units are set to 0
    fn extract_witnesses(
        tx_info: &TransactionInfo,
    ) -> Result<(Vec<csl::PlutusData>, Vec<csl::Redeemer>)> {
        let datums = tx_info
            .datums
            .0
            .iter()
            .map(|(_dh, Datum(d))| Ok(d.to_plutus_data().try_to_csl()?))
            .collect::<Result<_>>()?;

        let redeemers = tx_info
            .redeemers
            .0
            .iter()
            .filter_map(|(script_purpose, redeemer)| match script_purpose {
                ScriptPurpose::Spending(reference) => tx_info
                    .inputs
                    .iter()
                    .enumerate()
                    .find(|(_idx, tx_input)| &tx_input.reference == reference)
                    .map(|(idx, _)| {
                        Ok(RedeemerWithExtraInfo {
                            redeemer,
                            tag: &csl::RedeemerTag::new_spend(),
                            index: idx as u64,
                        }
                        .try_to_csl()?)
                    }),
                ScriptPurpose::Minting(reference) => tx_info
                    .mint
                    .0
                    .iter()
                    .filter(|(cur_sym, _)| match cur_sym {
                        CurrencySymbol::NativeToken(_) => true,
                        CurrencySymbol::Ada => false,
                    })
                    .enumerate()
                    .find(|(_idx, (currency_symbol, _assets))| currency_symbol == &reference)
                    .map(|(idx, _)| {
                        Ok(RedeemerWithExtraInfo {
                            redeemer,
                            tag: &csl::RedeemerTag::new_mint(),
                            index: idx as u64,
                        }
                        .try_to_csl()?)
                    }),
                _ => Some(Err(Error::Unsupported(
                    "Only spending and minting redeemers are supported".to_string(),
                ))),
            })
            .collect::<Result<_>>()?;

        Ok((datums, redeemers))
    }

    /// Collect witness scripts (validators and mintig policies)
    fn witness_scripts(
        tx_info: &TransactionInfo,
        scripts: &BTreeMap<ScriptHash, ScriptOrRef>,
    ) -> Result<Vec<csl::PlutusScript>> {
        Ok(tx_info
            .inputs
            .iter()
            .filter_map(
                |TxInInfo {
                     reference: _,
                     output,
                 }| {
                    match &output.address {
                        Address {
                            credential: Credential::Script(ValidatorHash(script_hash)),
                            staking_credential: _,
                        } => Some(script_hash),
                        _ => None,
                    }
                },
            )
            .chain(tx_info.mint.0.iter().filter_map(|(cs, _)| match cs {
                CurrencySymbol::NativeToken(MintingPolicyHash(script_hash)) => Some(script_hash),
                _ => None,
            }))
            .map(|script_hash| {
                scripts
                    .get(script_hash)
                    .cloned()
                    .ok_or(Error::MissingScript((*script_hash).clone()))
            })
            .collect::<Result<Vec<_>>>()?
            .into_iter()
            .filter_map(|script_or_ref| match script_or_ref {
                ScriptOrRef::PlutusScript(script) => Some(script),
                ScriptOrRef::RefScript(_, _) => None,
            })
            .collect())
    }

    /// Calculate script integrity hash
    fn calc_script_data_hash(
        &self,
        mut tx_builder: csl::TransactionBuilder,
        wit_datums: &[csl::PlutusData],
        wit_redeemers: &[csl::Redeemer],
    ) -> csl::TransactionBuilder {
        debug!("Calculating script integrity hash");
        let mut redeemers = csl::Redeemers::new();
        wit_redeemers.iter().for_each(|red| redeemers.add(red));

        if !wit_datums.is_empty() || !wit_redeemers.is_empty() {
            let datums = if wit_datums.is_empty() {
                None
            } else {
                let mut ds = csl::PlutusList::new();
                wit_datums.iter().for_each(|dat| ds.add(dat));
                Some(ds)
            };

            let mut used_langs = csl::Languages::new();
            used_langs.add(csl::Language::new_plutus_v2());

            let script_data_hash = csl::hash_script_data(
                &redeemers,
                &self.cost_models.retain_language_versions(&used_langs),
                datums,
            );

            tx_builder.set_script_data_hash(&script_data_hash);
        }
        tx_builder
    }

    /// Apply execution units to redeemers
    fn apply_ex_units(
        redeemer: &csl::Redeemer,
        ex_units_map: &BTreeMap<(csl::RedeemerTag, csl::BigNum), csl::ExUnits>,
    ) -> Result<csl::Redeemer> {
        debug!("Apply execution units.");
        let key = (redeemer.tag(), redeemer.index());
        let ex_units = ex_units_map.get(&key).ok_or(Error::MissingExUnits(key))?;
        Ok(csl::Redeemer::new(
            &redeemer.tag(),
            &redeemer.index(),
            &redeemer.data(),
            ex_units,
        ))
    }

    /// Calculate script integrity hash, balance the transaction and add change if necessary
    fn balance_transaction(
        &self,
        tx: &TxWithCtx<'_>,
        mut tx_builder: csl::TransactionBuilder,
        wit_datums: &[csl::PlutusData],
        wit_redeemers: &[csl::Redeemer],
    ) -> Result<csl::TransactionBody> {
        debug!("Balance transaction");
        let mut redeemers = csl::Redeemers::new();
        wit_redeemers.iter().for_each(|red| redeemers.add(red));

        tx_builder = self.calc_script_data_hash(tx_builder, wit_datums, wit_redeemers);

        let (change_addr, change_datum) = match tx.change_strategy {
            ChangeStrategy::Address(address) => (
                AddressWithExtraInfo {
                    address,
                    network_tag: self.network_id,
                }
                .try_to_csl()?,
                None,
            ),
            ChangeStrategy::LastOutput => {
                let last_output = tx
                    .tx_info
                    .outputs
                    .last()
                    .ok_or(Error::MissingChangeOutput)?;

                (
                    AddressWithExtraInfo {
                        address: &last_output.address,
                        network_tag: self.network_id,
                    }
                    .try_to_csl()?,
                    last_output.datum.try_to_csl()?,
                )
            }
        };

        match change_datum {
            None => tx_builder
                .add_change_if_needed(&change_addr)
                .map_err(|source| Error::TransactionBuildError(anyhow!(source)))?,
            Some(output_datum) => tx_builder
                .add_change_if_needed_with_datum(&change_addr, &output_datum)
                .map_err(|source| Error::TransactionBuildError(anyhow!(source)))?,
        };

        tx_builder
            .build()
            .map_err(|source| Error::TransactionBuildError(anyhow!(source)))
    }

    /// Convert a TransactionInfo into a valid TransactionBody and prepare all witnesses (except
    /// wallet signatures)
    /// If the transaction context does not include execution units, we use Ogmios to calculate
    /// those
    pub async fn bake_balanced_tx(
        &self,
        submitter: &impl Submitter,
        tx: TxWithCtx<'_>,
    ) -> Result<csl::FixedTransaction> {
        info!("Bake balanced transaction.");
        let (datums, redeemers) = TxBakery::extract_witnesses(tx.tx_info)?;
        let plutus_scripts = TxBakery::witness_scripts(tx.tx_info, tx.scripts)?;

        let aux_data: Result<Option<csl::AuxiliaryData>> = tx
            .metadata
            .map(|metadata| {
                let mut aux_data = csl::AuxiliaryData::new();
                aux_data.set_metadata(&metadata.try_into()?);
                Ok(aux_data)
            })
            .transpose();
        let aux_data = aux_data?;

        let (tx_builder, ex_units) = match &tx.ex_units_map {
            Some(ex_units_map) => {
                debug!("Using supplied execution units.");
                (self.mk_tx_builder(&tx)?, (*ex_units_map).clone())
            }
            None => {
                debug!("Using Ogmios to calculate execution units.");
                let tx_builder = self.mk_tx_builder(&tx)?;

                let ex_units = submitter
                    .evaluate_transaction(&tx_builder, &plutus_scripts, &redeemers)
                    .await?;

                debug!("Applying execution units to transaction.");

                (
                    self.mk_tx_builder(&tx.clone().with_ex_units(&ex_units))?,
                    ex_units,
                )
            }
        };

        let redeemers_w_ex_u = redeemers
            .iter()
            .map(|r| TxBakery::apply_ex_units(r, &ex_units))
            .collect::<Result<Vec<_>>>()?;

        let tx_body = self.balance_transaction(&tx, tx_builder, &datums, &redeemers_w_ex_u)?;

        let mut witness_set = csl::TransactionWitnessSet::new();
        let mut script_witnesses = csl::PlutusScripts::new();

        plutus_scripts
            .iter()
            .for_each(|script| script_witnesses.add(script));

        let mut redeemer_witnesses = csl::Redeemers::new();

        redeemers_w_ex_u
            .iter()
            .for_each(|redeemer| redeemer_witnesses.add(redeemer));

        witness_set.set_plutus_scripts(&script_witnesses);
        witness_set.set_redeemers(&redeemer_witnesses);

        let tx = csl::Transaction::new(&tx_body, &witness_set, aux_data);

        let fixed_tx = csl::FixedTransaction::from_bytes(tx.to_bytes())
            .map_err(|source| Error::TransactionBuildError(anyhow!(source)))?;

        Ok(fixed_tx)
    }

    /// Convert a TransactionInfo into a valid signed Transaction
    pub async fn bake_signed_tx(
        &self,
        submitter: &impl Submitter,
        wallet: &impl Wallet,
        tx: TxWithCtx<'_>,
    ) -> Result<csl::FixedTransaction> {
        let tx = self.bake_balanced_tx(submitter, tx).await?;
        debug!("Signing transaction.");
        Ok(wallet.sign_transaction(&tx))
    }

    /// Convert a TransactionInfo into a valid signed Transaction and submit it to the chain
    /// (Not waiting for confirmation)
    pub async fn bake_and_deliver(
        &self,
        submitter: &impl Submitter,
        wallet: &impl Wallet,
        tx: TxWithCtx<'_>,
    ) -> Result<TransactionHash> {
        let tx = self.bake_signed_tx(submitter, wallet, tx).await?;

        debug!("Submitting transaction.");
        Ok(submitter.submit_transaction(&tx).await?)
    }
}