cascade_cli/stack/
rebase.rs

1use crate::errors::{CascadeError, Result};
2use crate::git::{ConflictAnalyzer, GitRepository};
3use crate::stack::{Stack, StackManager};
4use chrono::Utc;
5use serde::{Deserialize, Serialize};
6use std::collections::HashMap;
7use tracing::{debug, info, warn};
8use uuid::Uuid;
9
10/// Conflict resolution result
11#[derive(Debug, Clone)]
12enum ConflictResolution {
13    /// Conflict was successfully resolved
14    Resolved,
15    /// Conflict is too complex for automatic resolution
16    TooComplex,
17}
18
19/// Represents a conflict region in a file
20#[derive(Debug, Clone)]
21#[allow(dead_code)]
22struct ConflictRegion {
23    /// Byte position where conflict starts
24    start: usize,
25    /// Byte position where conflict ends  
26    end: usize,
27    /// Line number where conflict starts
28    start_line: usize,
29    /// Line number where conflict ends
30    end_line: usize,
31    /// Content from "our" side (before separator)
32    our_content: String,
33    /// Content from "their" side (after separator)
34    their_content: String,
35}
36
37/// Strategy for rebasing stacks (force-push is the only valid approach for preserving PR history)
38#[derive(Debug, Clone, Serialize, Deserialize, PartialEq)]
39pub enum RebaseStrategy {
40    /// Force-push rebased commits to original branches (preserves PR history)
41    /// This is the industry standard used by Graphite, Phabricator, spr, etc.
42    ForcePush,
43    /// Interactive rebase with conflict resolution
44    Interactive,
45}
46
47/// Options for rebase operations
48#[derive(Debug, Clone)]
49pub struct RebaseOptions {
50    /// The rebase strategy to use
51    pub strategy: RebaseStrategy,
52    /// Whether to run interactively (prompt for user input)
53    pub interactive: bool,
54    /// Target base branch to rebase onto
55    pub target_base: Option<String>,
56    /// Whether to preserve merge commits
57    pub preserve_merges: bool,
58    /// Whether to auto-resolve simple conflicts
59    pub auto_resolve: bool,
60    /// Maximum number of retries for conflict resolution
61    pub max_retries: usize,
62    /// Skip pulling latest changes (when already done by caller)
63    pub skip_pull: Option<bool>,
64    /// Original working branch to restore after rebase (if different from base)
65    /// This is critical to prevent updating the base branch when sync checks out to it
66    pub original_working_branch: Option<String>,
67}
68
69/// Result of a rebase operation
70#[derive(Debug)]
71pub struct RebaseResult {
72    /// Whether the rebase was successful
73    pub success: bool,
74    /// Old branch to new branch mapping
75    pub branch_mapping: HashMap<String, String>,
76    /// Commits that had conflicts
77    pub conflicts: Vec<String>,
78    /// New commit hashes
79    pub new_commits: Vec<String>,
80    /// Error message if rebase failed
81    pub error: Option<String>,
82    /// Summary of changes made
83    pub summary: String,
84}
85
86/// RAII guard to ensure temporary branches are cleaned up even on error/panic
87///
88/// This stores branch names and provides a cleanup method that can be called
89/// with a GitRepository reference. The Drop trait ensures cleanup happens
90/// even if the rebase function panics or returns early with an error.
91#[allow(dead_code)]
92struct TempBranchCleanupGuard {
93    branches: Vec<String>,
94    cleaned: bool,
95}
96
97#[allow(dead_code)]
98impl TempBranchCleanupGuard {
99    fn new() -> Self {
100        Self {
101            branches: Vec::new(),
102            cleaned: false,
103        }
104    }
105
106    fn add_branch(&mut self, branch: String) {
107        self.branches.push(branch);
108    }
109
110    /// Perform cleanup with provided git repository
111    fn cleanup(&mut self, git_repo: &GitRepository) {
112        if self.cleaned || self.branches.is_empty() {
113            return;
114        }
115
116        info!("๐Ÿงน Cleaning up {} temporary branches", self.branches.len());
117        for branch in &self.branches {
118            if let Err(e) = git_repo.delete_branch_unsafe(branch) {
119                warn!("Failed to delete temp branch {}: {}", branch, e);
120                // Continue with cleanup even if one fails
121            }
122        }
123        self.cleaned = true;
124    }
125}
126
127impl Drop for TempBranchCleanupGuard {
128    fn drop(&mut self) {
129        if !self.cleaned && !self.branches.is_empty() {
130            // This path is only hit on panic or unexpected early return
131            // We can't access git_repo here, so just log the branches that need manual cleanup
132            warn!(
133                "โš ๏ธ  {} temporary branches were not cleaned up: {}",
134                self.branches.len(),
135                self.branches.join(", ")
136            );
137            warn!("Run 'ca cleanup' to remove orphaned temporary branches");
138        }
139    }
140}
141
142/// Manages rebase operations for stacks
143pub struct RebaseManager {
144    stack_manager: StackManager,
145    git_repo: GitRepository,
146    options: RebaseOptions,
147    conflict_analyzer: ConflictAnalyzer,
148}
149
150impl Default for RebaseOptions {
151    fn default() -> Self {
152        Self {
153            strategy: RebaseStrategy::ForcePush,
154            interactive: false,
155            target_base: None,
156            preserve_merges: true,
157            auto_resolve: true,
158            max_retries: 3,
159            skip_pull: None,
160            original_working_branch: None,
161        }
162    }
163}
164
165impl RebaseManager {
166    /// Create a new rebase manager
167    pub fn new(
168        stack_manager: StackManager,
169        git_repo: GitRepository,
170        options: RebaseOptions,
171    ) -> Self {
172        Self {
173            stack_manager,
174            git_repo,
175            options,
176            conflict_analyzer: ConflictAnalyzer::new(),
177        }
178    }
179
180    /// Consume the rebase manager and return the updated stack manager
181    pub fn into_stack_manager(self) -> StackManager {
182        self.stack_manager
183    }
184
185    /// Rebase an entire stack onto a new base
186    pub fn rebase_stack(&mut self, stack_id: &Uuid) -> Result<RebaseResult> {
187        debug!("Starting rebase for stack {}", stack_id);
188
189        let stack = self
190            .stack_manager
191            .get_stack(stack_id)
192            .ok_or_else(|| CascadeError::config(format!("Stack {stack_id} not found")))?
193            .clone();
194
195        match self.options.strategy {
196            RebaseStrategy::ForcePush => self.rebase_with_force_push(&stack),
197            RebaseStrategy::Interactive => self.rebase_interactive(&stack),
198        }
199    }
200
201    /// Rebase using force-push strategy (industry standard for stacked diffs)
202    /// This updates local branches in-place, then force-pushes ONLY branches with existing PRs
203    /// to preserve PR history - the approach used by Graphite, Phabricator, spr, etc.
204    fn rebase_with_force_push(&mut self, stack: &Stack) -> Result<RebaseResult> {
205        use crate::cli::output::Output;
206
207        // Check if there's an in-progress cherry-pick from a previous failed sync
208        if self.has_in_progress_cherry_pick()? {
209            return self.handle_in_progress_cherry_pick(stack);
210        }
211
212        Output::section(format!("Rebasing stack: {}", stack.name));
213
214        let mut result = RebaseResult {
215            success: true,
216            branch_mapping: HashMap::new(),
217            conflicts: Vec::new(),
218            new_commits: Vec::new(),
219            error: None,
220            summary: String::new(),
221        };
222
223        let target_base = self
224            .options
225            .target_base
226            .as_ref()
227            .unwrap_or(&stack.base_branch)
228            .clone(); // Clone to avoid borrow issues
229
230        // Use the original working branch passed in options, or detect current branch
231        // CRITICAL: sync_stack passes the original branch before it checks out to base
232        // This prevents us from thinking we started on the base branch
233        let original_branch = self
234            .options
235            .original_working_branch
236            .clone()
237            .or_else(|| self.git_repo.get_current_branch().ok());
238
239        // SAFETY: Warn if we're starting on the base branch (unusual but valid)
240        // This can happen if user manually runs rebase while on base branch
241        if let Some(ref orig) = original_branch {
242            if orig == &target_base {
243                debug!(
244                    "Original working branch is base branch '{}' - will skip working branch update",
245                    orig
246                );
247            }
248        }
249
250        // Note: Caller (sync_stack) has already checked out base branch when skip_pull=true
251        // Only pull if not already done by caller (like sync command)
252        if !self.options.skip_pull.unwrap_or(false) {
253            if let Err(e) = self.pull_latest_changes(&target_base) {
254                Output::warning(format!("Could not pull latest changes: {}", e));
255            }
256        }
257
258        // Reset working directory to clean state before rebase
259        if let Err(e) = self.git_repo.reset_to_head() {
260            Output::warning(format!("Could not reset working directory: {}", e));
261        }
262
263        let mut current_base = target_base.clone();
264        let entry_count = stack.entries.len();
265        let mut temp_branches: Vec<String> = Vec::new(); // Track temp branches for cleanup
266        let mut branches_to_push: Vec<(String, String)> = Vec::new(); // (branch_name, pr_number)
267
268        // Handle empty stack early
269        if entry_count == 0 {
270            println!(); // Spacing
271            Output::info("Stack has no entries yet");
272            Output::tip("Use 'ca push' to add commits to this stack");
273
274            result.summary = "Stack is empty".to_string();
275
276            // Print success with summary (consistent with non-empty path)
277            println!(); // Spacing
278            Output::success(&result.summary);
279
280            // Save metadata and return
281            self.stack_manager.save_to_disk()?;
282            return Ok(result);
283        }
284
285        println!(); // Spacing before tree
286        let plural = if entry_count == 1 { "entry" } else { "entries" };
287        println!("Rebasing {} {}...", entry_count, plural);
288
289        // Phase 1: Rebase all entries locally (libgit2 only - no CLI commands)
290        for (index, entry) in stack.entries.iter().enumerate() {
291            let original_branch = &entry.branch;
292
293            // Check if this entry is already correctly based on the current base
294            // If so, skip rebasing it (avoids creating duplicate commits)
295            if self
296                .git_repo
297                .is_commit_based_on(&entry.commit_hash, &current_base)
298                .unwrap_or(false)
299            {
300                tracing::debug!(
301                    "Entry '{}' is already correctly based on '{}', skipping rebase",
302                    original_branch,
303                    current_base
304                );
305
306                // Track which branches need to be pushed (only those with PRs)
307                let tree_char = if index + 1 == entry_count {
308                    "โ””โ”€"
309                } else {
310                    "โ”œโ”€"
311                };
312
313                if let Some(pr_num) = &entry.pull_request_id {
314                    println!("   {} {} (PR #{})", tree_char, original_branch, pr_num);
315                    branches_to_push.push((original_branch.clone(), pr_num.clone()));
316                } else {
317                    println!("   {} {} (not submitted)", tree_char, original_branch);
318                }
319
320                result
321                    .branch_mapping
322                    .insert(original_branch.clone(), original_branch.clone());
323
324                // This branch becomes the base for the next entry
325                current_base = original_branch.clone();
326                continue;
327            }
328
329            // Create a temporary branch from the current base
330            // This avoids committing directly to protected branches like develop/main
331            let temp_branch = format!("{}-temp-{}", original_branch, Utc::now().timestamp());
332            temp_branches.push(temp_branch.clone()); // Track for cleanup
333            self.git_repo
334                .create_branch(&temp_branch, Some(&current_base))?;
335            self.git_repo.checkout_branch_silent(&temp_branch)?;
336
337            // Cherry-pick the commit onto the temp branch (NOT the protected base!)
338            match self.cherry_pick_commit(&entry.commit_hash) {
339                Ok(new_commit_hash) => {
340                    result.new_commits.push(new_commit_hash.clone());
341
342                    // Get the commit that's now at HEAD (the cherry-picked commit)
343                    let rebased_commit_id = self.git_repo.get_head_commit()?.id().to_string();
344
345                    // Update the original branch to point to this rebased commit
346                    // This is LOCAL ONLY - moves refs/heads/<branch> to the commit on temp branch
347                    self.git_repo
348                        .update_branch_to_commit(original_branch, &rebased_commit_id)?;
349
350                    // Track which branches need to be pushed (only those with PRs)
351                    let tree_char = if index + 1 == entry_count {
352                        "โ””โ”€"
353                    } else {
354                        "โ”œโ”€"
355                    };
356
357                    if let Some(pr_num) = &entry.pull_request_id {
358                        println!("   {} {} (PR #{})", tree_char, original_branch, pr_num);
359                        branches_to_push.push((original_branch.clone(), pr_num.clone()));
360                    } else {
361                        println!("   {} {} (not submitted)", tree_char, original_branch);
362                    }
363
364                    result
365                        .branch_mapping
366                        .insert(original_branch.clone(), original_branch.clone());
367
368                    // Update stack entry with new commit hash
369                    self.update_stack_entry(
370                        stack.id,
371                        &entry.id,
372                        original_branch,
373                        &rebased_commit_id,
374                    )?;
375
376                    // This branch becomes the base for the next entry
377                    current_base = original_branch.clone();
378                }
379                Err(e) => {
380                    result.conflicts.push(entry.commit_hash.clone());
381
382                    if !self.options.auto_resolve {
383                        println!(); // Spacing before error
384                        Output::error(e.to_string());
385                        result.success = false;
386                        result.error = Some(format!(
387                            "Conflict in {}: {}\n\n\
388                            MANUAL CONFLICT RESOLUTION REQUIRED\n\
389                            =====================================\n\n\
390                            Step 1: Analyze conflicts\n\
391                            โ†’ Run: ca conflicts\n\
392                            โ†’ This shows which conflicts are in which files\n\n\
393                            Step 2: Resolve conflicts in your editor\n\
394                            โ†’ Open conflicted files and edit them\n\
395                            โ†’ Remove conflict markers (<<<<<<, ======, >>>>>>)\n\
396                            โ†’ Keep the code you want\n\
397                            โ†’ Save the files\n\n\
398                            Step 3: Mark conflicts as resolved\n\
399                            โ†’ Run: git add <resolved-files>\n\
400                            โ†’ Or: git add -A (to stage all resolved files)\n\n\
401                            Step 4: Complete the sync\n\
402                            โ†’ Run: ca sync\n\
403                            โ†’ Cascade will detect resolved conflicts and continue\n\n\
404                            Alternative: Abort and start over\n\
405                            โ†’ Run: git cherry-pick --abort\n\
406                            โ†’ Then: ca sync (starts fresh)\n\n\
407                            TIP: Enable auto-resolution for simple conflicts:\n\
408                            โ†’ Run: ca sync --auto-resolve\n\
409                            โ†’ Only complex conflicts will require manual resolution",
410                            entry.commit_hash, e
411                        ));
412                        break;
413                    }
414
415                    // Try to resolve automatically
416                    match self.auto_resolve_conflicts(&entry.commit_hash) {
417                        Ok(fully_resolved) => {
418                            if !fully_resolved {
419                                result.success = false;
420                                result.error = Some(format!(
421                                    "Conflicts in commit {}\n\n\
422                                    To resolve:\n\
423                                    1. Fix conflicts in your editor\n\
424                                    2. Run: ca sync --continue\n\n\
425                                    Or abort:\n\
426                                    โ†’ Run: git cherry-pick --abort",
427                                    &entry.commit_hash[..8]
428                                ));
429                                break;
430                            }
431
432                            // Commit the resolved changes
433                            let commit_message =
434                                format!("Auto-resolved conflicts in {}", &entry.commit_hash[..8]);
435
436                            // CRITICAL: Check if there are actually changes to commit
437                            debug!("Checking staged files before commit");
438                            let staged_files = self.git_repo.get_staged_files()?;
439
440                            if staged_files.is_empty() {
441                                // NO FILES STAGED! This means auto-resolve didn't actually stage anything
442                                // This is the bug - cherry-pick failed, but has_conflicts() returned false
443                                // so auto-resolve exited early without staging anything
444                                result.success = false;
445                                result.error = Some(format!(
446                                    "CRITICAL BUG DETECTED: Cherry-pick failed but no files were staged!\n\n\
447                                    This indicates a Git state issue after cherry-pick failure.\n\n\
448                                    RECOVERY STEPS:\n\
449                                    ================\n\n\
450                                    Step 1: Check Git status\n\
451                                    โ†’ Run: git status\n\
452                                    โ†’ Check if there are any changes in working directory\n\n\
453                                    Step 2: Check for conflicts manually\n\
454                                    โ†’ Run: git diff\n\
455                                    โ†’ Look for conflict markers (<<<<<<, ======, >>>>>>)\n\n\
456                                    Step 3: Abort the cherry-pick\n\
457                                    โ†’ Run: git cherry-pick --abort\n\n\
458                                    Step 4: Report this bug\n\
459                                    โ†’ This is a known issue we're investigating\n\
460                                    โ†’ Cherry-pick failed for commit {}\n\
461                                    โ†’ But Git reported no conflicts and no staged files\n\n\
462                                    Step 5: Try manual resolution\n\
463                                    โ†’ Run: ca sync --no-auto-resolve\n\
464                                    โ†’ Manually resolve conflicts as they appear",
465                                    &entry.commit_hash[..8]
466                                ));
467                                warn!("CRITICAL - No files staged after auto-resolve!");
468                                break;
469                            }
470
471                            debug!("{} files staged", staged_files.len());
472
473                            match self.git_repo.commit(&commit_message) {
474                                Ok(new_commit_id) => {
475                                    debug!(
476                                        "Created commit {} with message '{}'",
477                                        &new_commit_id[..8],
478                                        commit_message
479                                    );
480
481                                    Output::success("Auto-resolved conflicts");
482                                    result.new_commits.push(new_commit_id.clone());
483                                    let rebased_commit_id = new_commit_id;
484
485                                    // Update the original branch to point to this rebased commit
486                                    self.git_repo.update_branch_to_commit(
487                                        original_branch,
488                                        &rebased_commit_id,
489                                    )?;
490
491                                    // Track which branches need to be pushed (only those with PRs)
492                                    let tree_char = if index + 1 == entry_count {
493                                        "โ””โ”€"
494                                    } else {
495                                        "โ”œโ”€"
496                                    };
497
498                                    if let Some(pr_num) = &entry.pull_request_id {
499                                        println!(
500                                            "   {} {} (PR #{})",
501                                            tree_char, original_branch, pr_num
502                                        );
503                                        branches_to_push
504                                            .push((original_branch.clone(), pr_num.clone()));
505                                    } else {
506                                        println!(
507                                            "   {} {} (not submitted)",
508                                            tree_char, original_branch
509                                        );
510                                    }
511
512                                    result
513                                        .branch_mapping
514                                        .insert(original_branch.clone(), original_branch.clone());
515
516                                    // Update stack entry with new commit hash
517                                    self.update_stack_entry(
518                                        stack.id,
519                                        &entry.id,
520                                        original_branch,
521                                        &rebased_commit_id,
522                                    )?;
523
524                                    // This branch becomes the base for the next entry
525                                    current_base = original_branch.clone();
526                                }
527                                Err(commit_err) => {
528                                    result.success = false;
529                                    result.error = Some(format!(
530                                        "Could not commit auto-resolved conflicts: {}\n\n\
531                                        This usually means:\n\
532                                        - Git index is locked (another process accessing repo)\n\
533                                        - File permissions issue\n\
534                                        - Disk space issue\n\n\
535                                        Recovery:\n\
536                                        1. Check if another Git operation is running\n\
537                                        2. Run 'rm -f .git/index.lock' if stale lock exists\n\
538                                        3. Run 'git status' to check repo state\n\
539                                        4. Retry 'ca sync' after fixing the issue",
540                                        commit_err
541                                    ));
542                                    break;
543                                }
544                            }
545                        }
546                        Err(resolve_err) => {
547                            result.success = false;
548                            result.error = Some(format!(
549                                "Could not resolve conflicts: {}\n\n\
550                                Recovery:\n\
551                                1. Check repo state: 'git status'\n\
552                                2. If files are staged, commit or reset them: 'git reset --hard HEAD'\n\
553                                3. Remove any lock files: 'rm -f .git/index.lock'\n\
554                                4. Retry 'ca sync'",
555                                resolve_err
556                            ));
557                            break;
558                        }
559                    }
560                }
561            }
562        }
563
564        // Cleanup temp branches before returning to original branch
565        // Must checkout away from temp branches first
566        if !temp_branches.is_empty() {
567            // Force checkout to base branch to allow temp branch deletion
568            // Use unsafe checkout to bypass safety checks since we know this is cleanup
569            if let Err(e) = self.git_repo.checkout_branch_unsafe(&target_base) {
570                debug!("Could not checkout base for cleanup: {}", e);
571                // If we can't checkout, we can't delete temp branches
572                // This is non-critical - temp branches will be cleaned up eventually
573            } else {
574                // Successfully checked out - now delete temp branches
575                for temp_branch in &temp_branches {
576                    if let Err(e) = self.git_repo.delete_branch_unsafe(temp_branch) {
577                        debug!("Could not delete temp branch {}: {}", temp_branch, e);
578                    }
579                }
580            }
581        }
582
583        // Phase 2: Push all branches with PRs to remote (git CLI - after all libgit2 operations)
584        // This batch approach prevents index lock conflicts between libgit2 and git CLI
585        let pushed_count = branches_to_push.len();
586        let skipped_count = entry_count - pushed_count;
587
588        if !branches_to_push.is_empty() {
589            // Push branches silently - user will see the summary
590
591            for (branch_name, _pr_num) in &branches_to_push {
592                match self.git_repo.force_push_single_branch_auto(branch_name) {
593                    Ok(_) => {
594                        debug!("Pushed {} successfully", branch_name);
595                    }
596                    Err(e) => {
597                        Output::warning(format!("Could not push '{}': {}", branch_name, e));
598                        // Continue pushing other branches even if one fails
599                    }
600                }
601            }
602        }
603
604        // Update working branch to point to the top of the rebased stack
605        // This ensures subsequent `ca push` doesn't re-add old commits
606        if let Some(ref orig_branch) = original_branch {
607            // CRITICAL: Never update the base branch! Only update working branches
608            if orig_branch != &target_base {
609                // Get the last entry's branch (top of stack)
610                if let Some(last_entry) = stack.entries.last() {
611                    let top_branch = &last_entry.branch;
612
613                    // Force-update working branch to point to same commit as top entry
614                    if let Ok(top_commit) = self.git_repo.get_branch_head(top_branch) {
615                        debug!(
616                            "Updating working branch '{}' to match top of stack ({})",
617                            orig_branch,
618                            &top_commit[..8]
619                        );
620
621                        if let Err(e) = self
622                            .git_repo
623                            .update_branch_to_commit(orig_branch, &top_commit)
624                        {
625                            Output::warning(format!(
626                                "Could not update working branch '{}' to top of stack: {}",
627                                orig_branch, e
628                            ));
629                        }
630                    }
631                }
632
633                // Return to original working branch
634                // Use unsafe checkout to force it (we're in cleanup phase, no uncommitted changes)
635                if let Err(e) = self.git_repo.checkout_branch_unsafe(orig_branch) {
636                    debug!(
637                        "Could not return to original branch '{}': {}",
638                        orig_branch, e
639                    );
640                    // Non-critical: User is left on base branch instead of working branch
641                }
642            } else {
643                // User was on base branch - this is unusual but valid
644                // Don't update base branch, just checkout back to it
645                debug!(
646                    "Skipping working branch update - user was on base branch '{}'",
647                    orig_branch
648                );
649                if let Err(e) = self.git_repo.checkout_branch_unsafe(orig_branch) {
650                    debug!("Could not return to base branch '{}': {}", orig_branch, e);
651                }
652            }
653        }
654
655        // Build summary message
656        result.summary = if pushed_count > 0 {
657            let pr_plural = if pushed_count == 1 { "" } else { "s" };
658            let entry_plural = if entry_count == 1 { "entry" } else { "entries" };
659
660            if skipped_count > 0 {
661                format!(
662                    "{} {} rebased ({} PR{} updated, {} not yet submitted)",
663                    entry_count, entry_plural, pushed_count, pr_plural, skipped_count
664                )
665            } else {
666                format!(
667                    "{} {} rebased ({} PR{} updated)",
668                    entry_count, entry_plural, pushed_count, pr_plural
669                )
670            }
671        } else {
672            let plural = if entry_count == 1 { "entry" } else { "entries" };
673            format!("{} {} rebased (no PRs to update yet)", entry_count, plural)
674        };
675
676        // Display result with proper formatting
677        println!(); // Spacing after tree
678        if result.success {
679            Output::success(&result.summary);
680        } else {
681            // Display error with proper icon
682            let error_msg = result
683                .error
684                .as_deref()
685                .unwrap_or("Rebase failed for unknown reason");
686            Output::error(error_msg);
687        }
688
689        // Save the updated stack metadata to disk
690        self.stack_manager.save_to_disk()?;
691
692        // CRITICAL: Return error if rebase failed
693        // Don't return Ok(result) with result.success = false - that's confusing!
694        if !result.success {
695            // Include the detailed error message (which contains conflict info)
696            let detailed_error = result.error.as_deref().unwrap_or("Rebase failed");
697            return Err(CascadeError::Branch(detailed_error.to_string()));
698        }
699
700        Ok(result)
701    }
702
703    /// Interactive rebase with user input
704    fn rebase_interactive(&mut self, stack: &Stack) -> Result<RebaseResult> {
705        info!("Starting interactive rebase for stack '{}'", stack.name);
706
707        let mut result = RebaseResult {
708            success: true,
709            branch_mapping: HashMap::new(),
710            conflicts: Vec::new(),
711            new_commits: Vec::new(),
712            error: None,
713            summary: String::new(),
714        };
715
716        println!("Interactive Rebase for Stack: {}", stack.name);
717        println!("   Base branch: {}", stack.base_branch);
718        println!("   Entries: {}", stack.entries.len());
719
720        if self.options.interactive {
721            println!("\nChoose action for each commit:");
722            println!("  (p)ick   - apply the commit");
723            println!("  (s)kip   - skip this commit");
724            println!("  (e)dit   - edit the commit message");
725            println!("  (q)uit   - abort the rebase");
726        }
727
728        // For now, automatically pick all commits
729        // In a real implementation, this would prompt the user
730        for entry in &stack.entries {
731            println!(
732                "  {} {} - {}",
733                entry.short_hash(),
734                entry.branch,
735                entry.short_message(50)
736            );
737
738            // Auto-pick for demo purposes
739            match self.cherry_pick_commit(&entry.commit_hash) {
740                Ok(new_commit) => result.new_commits.push(new_commit),
741                Err(_) => result.conflicts.push(entry.commit_hash.clone()),
742            }
743        }
744
745        result.summary = format!(
746            "Interactive rebase processed {} commits",
747            stack.entries.len()
748        );
749        Ok(result)
750    }
751
752    /// Cherry-pick a commit onto the current branch
753    fn cherry_pick_commit(&self, commit_hash: &str) -> Result<String> {
754        // Use the real cherry-pick implementation from GitRepository
755        let new_commit_hash = self.git_repo.cherry_pick(commit_hash)?;
756
757        // Check for any leftover staged changes after successful cherry-pick
758        if let Ok(staged_files) = self.git_repo.get_staged_files() {
759            if !staged_files.is_empty() {
760                // Commit any leftover staged changes silently
761                let cleanup_message = format!("Cleanup after cherry-pick {}", &commit_hash[..8]);
762                let _ = self.git_repo.commit_staged_changes(&cleanup_message);
763            }
764        }
765
766        Ok(new_commit_hash)
767    }
768
769    /// Attempt to automatically resolve conflicts
770    fn auto_resolve_conflicts(&self, commit_hash: &str) -> Result<bool> {
771        debug!("Starting auto-resolve for commit {}", commit_hash);
772
773        // Check if there are actually conflicts
774        let has_conflicts = self.git_repo.has_conflicts()?;
775        debug!("has_conflicts() = {}", has_conflicts);
776
777        // Check if cherry-pick is in progress
778        let cherry_pick_head = self.git_repo.path().join(".git").join("CHERRY_PICK_HEAD");
779        let cherry_pick_in_progress = cherry_pick_head.exists();
780
781        if !has_conflicts {
782            debug!("No conflicts detected by Git index");
783
784            // If cherry-pick is in progress but no conflicts detected, something is wrong
785            if cherry_pick_in_progress {
786                warn!("CHERRY_PICK_HEAD exists but no conflicts in index - aborting cherry-pick");
787
788                // Abort the cherry-pick to clean up
789                let _ = std::process::Command::new("git")
790                    .args(["cherry-pick", "--abort"])
791                    .current_dir(self.git_repo.path())
792                    .output();
793
794                return Err(CascadeError::Branch(format!(
795                    "Cherry-pick failed for {} but Git index shows no conflicts. \
796                     This usually means the cherry-pick was aborted or failed in an unexpected way. \
797                     Please try manual resolution.",
798                    &commit_hash[..8]
799                )));
800            }
801
802            return Ok(true);
803        }
804
805        let conflicted_files = self.git_repo.get_conflicted_files()?;
806
807        if conflicted_files.is_empty() {
808            debug!("Conflicted files list is empty");
809            return Ok(true);
810        }
811
812        debug!(
813            "Found conflicts in {} files: {:?}",
814            conflicted_files.len(),
815            conflicted_files
816        );
817
818        // Use the new conflict analyzer for detailed analysis
819        let analysis = self
820            .conflict_analyzer
821            .analyze_conflicts(&conflicted_files, self.git_repo.path())?;
822
823        debug!(
824            "Conflict analysis: {} total conflicts, {} auto-resolvable",
825            analysis.total_conflicts, analysis.auto_resolvable_count
826        );
827
828        // Display recommendations
829        for recommendation in &analysis.recommendations {
830            debug!("{}", recommendation);
831        }
832
833        let mut resolved_count = 0;
834        let mut resolved_files = Vec::new(); // Track which files were actually resolved
835        let mut failed_files = Vec::new();
836
837        for file_analysis in &analysis.files {
838            debug!(
839                "Processing file: {} (auto_resolvable: {}, conflicts: {})",
840                file_analysis.file_path,
841                file_analysis.auto_resolvable,
842                file_analysis.conflicts.len()
843            );
844
845            if file_analysis.auto_resolvable {
846                match self.resolve_file_conflicts_enhanced(
847                    &file_analysis.file_path,
848                    &file_analysis.conflicts,
849                ) {
850                    Ok(ConflictResolution::Resolved) => {
851                        resolved_count += 1;
852                        resolved_files.push(file_analysis.file_path.clone());
853                        debug!("Successfully resolved {}", file_analysis.file_path);
854                    }
855                    Ok(ConflictResolution::TooComplex) => {
856                        debug!(
857                            "{} too complex for auto-resolution",
858                            file_analysis.file_path
859                        );
860                        failed_files.push(file_analysis.file_path.clone());
861                    }
862                    Err(e) => {
863                        debug!("Failed to resolve {}: {}", file_analysis.file_path, e);
864                        failed_files.push(file_analysis.file_path.clone());
865                    }
866                }
867            } else {
868                failed_files.push(file_analysis.file_path.clone());
869                debug!(
870                    "{} requires manual resolution ({} conflicts)",
871                    file_analysis.file_path,
872                    file_analysis.conflicts.len()
873                );
874            }
875        }
876
877        if resolved_count > 0 {
878            debug!(
879                "Resolved {}/{} files",
880                resolved_count,
881                conflicted_files.len()
882            );
883            debug!("Resolved files: {:?}", resolved_files);
884
885            // CRITICAL: Only stage files that were successfully resolved
886            // This prevents staging files that still have conflict markers
887            let file_paths: Vec<&str> = resolved_files.iter().map(|s| s.as_str()).collect();
888            debug!("Staging {} files", file_paths.len());
889            self.git_repo.stage_files(&file_paths)?;
890            debug!("Files staged successfully");
891        } else {
892            debug!("No files were resolved (resolved_count = 0)");
893        }
894
895        // Return true only if ALL conflicts were resolved
896        let all_resolved = failed_files.is_empty();
897
898        debug!(
899            "all_resolved = {}, failed_files = {:?}",
900            all_resolved, failed_files
901        );
902
903        if !all_resolved {
904            debug!("{} files still need manual resolution", failed_files.len());
905        }
906
907        debug!("Returning all_resolved = {}", all_resolved);
908        Ok(all_resolved)
909    }
910
911    /// Resolve conflicts using enhanced analysis
912    fn resolve_file_conflicts_enhanced(
913        &self,
914        file_path: &str,
915        conflicts: &[crate::git::ConflictRegion],
916    ) -> Result<ConflictResolution> {
917        let repo_path = self.git_repo.path();
918        let full_path = repo_path.join(file_path);
919
920        // Read the file content with conflict markers
921        let mut content = std::fs::read_to_string(&full_path)
922            .map_err(|e| CascadeError::config(format!("Failed to read file {file_path}: {e}")))?;
923
924        if conflicts.is_empty() {
925            return Ok(ConflictResolution::Resolved);
926        }
927
928        info!(
929            "Resolving {} conflicts in {} using enhanced analysis",
930            conflicts.len(),
931            file_path
932        );
933
934        let mut any_resolved = false;
935
936        // Process conflicts in reverse order to maintain string indices
937        for conflict in conflicts.iter().rev() {
938            match self.resolve_single_conflict_enhanced(conflict) {
939                Ok(Some(resolution)) => {
940                    // Replace the conflict region with the resolved content
941                    let before = &content[..conflict.start_pos];
942                    let after = &content[conflict.end_pos..];
943                    content = format!("{before}{resolution}{after}");
944                    any_resolved = true;
945                    debug!(
946                        "โœ… Resolved {} conflict at lines {}-{} in {}",
947                        format!("{:?}", conflict.conflict_type).to_lowercase(),
948                        conflict.start_line,
949                        conflict.end_line,
950                        file_path
951                    );
952                }
953                Ok(None) => {
954                    debug!(
955                        "โš ๏ธ  {} conflict at lines {}-{} in {} requires manual resolution",
956                        format!("{:?}", conflict.conflict_type).to_lowercase(),
957                        conflict.start_line,
958                        conflict.end_line,
959                        file_path
960                    );
961                    return Ok(ConflictResolution::TooComplex);
962                }
963                Err(e) => {
964                    debug!("โŒ Failed to resolve conflict in {}: {}", file_path, e);
965                    return Ok(ConflictResolution::TooComplex);
966                }
967            }
968        }
969
970        if any_resolved {
971            // Check if we resolved ALL conflicts in this file
972            let remaining_conflicts = self.parse_conflict_markers(&content)?;
973
974            if remaining_conflicts.is_empty() {
975                debug!(
976                    "All conflicts resolved in {}, content length: {} bytes",
977                    file_path,
978                    content.len()
979                );
980
981                // CRITICAL SAFETY CHECK: Don't write empty files!
982                if content.trim().is_empty() {
983                    warn!(
984                        "SAFETY CHECK: Resolved content for {} is empty! Aborting auto-resolution.",
985                        file_path
986                    );
987                    return Ok(ConflictResolution::TooComplex);
988                }
989
990                // SAFETY: Create backup before writing resolved content
991                let backup_path = full_path.with_extension("cascade-backup");
992                if let Ok(original_content) = std::fs::read_to_string(&full_path) {
993                    debug!(
994                        "Backup for {} (original: {} bytes, resolved: {} bytes)",
995                        file_path,
996                        original_content.len(),
997                        content.len()
998                    );
999                    let _ = std::fs::write(&backup_path, original_content);
1000                }
1001
1002                // All conflicts resolved - write the file back atomically
1003                crate::utils::atomic_file::write_string(&full_path, &content)?;
1004
1005                debug!("Wrote {} bytes to {}", content.len(), file_path);
1006                return Ok(ConflictResolution::Resolved);
1007            } else {
1008                info!(
1009                    "Partially resolved conflicts in {} ({} remaining)",
1010                    file_path,
1011                    remaining_conflicts.len()
1012                );
1013            }
1014        }
1015
1016        Ok(ConflictResolution::TooComplex)
1017    }
1018
1019    /// Helper to count whitespace consistency (lower is better)
1020    #[allow(dead_code)]
1021    fn count_whitespace_consistency(content: &str) -> usize {
1022        let mut inconsistencies = 0;
1023        let lines: Vec<&str> = content.lines().collect();
1024
1025        for line in &lines {
1026            // Check for mixed tabs and spaces
1027            if line.contains('\t') && line.contains(' ') {
1028                inconsistencies += 1;
1029            }
1030        }
1031
1032        // Penalize for inconsistencies
1033        lines.len().saturating_sub(inconsistencies)
1034    }
1035
1036    /// Resolve a single conflict using enhanced analysis
1037    fn resolve_single_conflict_enhanced(
1038        &self,
1039        conflict: &crate::git::ConflictRegion,
1040    ) -> Result<Option<String>> {
1041        debug!(
1042            "Resolving {} conflict in {} (lines {}-{})",
1043            format!("{:?}", conflict.conflict_type).to_lowercase(),
1044            conflict.file_path,
1045            conflict.start_line,
1046            conflict.end_line
1047        );
1048
1049        use crate::git::ConflictType;
1050
1051        match conflict.conflict_type {
1052            ConflictType::Whitespace => {
1053                // SAFETY: Only resolve if the content is truly identical except for whitespace
1054                // Otherwise, it might be intentional formatting changes
1055                let our_normalized = conflict
1056                    .our_content
1057                    .split_whitespace()
1058                    .collect::<Vec<_>>()
1059                    .join(" ");
1060                let their_normalized = conflict
1061                    .their_content
1062                    .split_whitespace()
1063                    .collect::<Vec<_>>()
1064                    .join(" ");
1065
1066                if our_normalized == their_normalized {
1067                    // Content is identical - in cherry-pick context, ALWAYS prefer THEIRS
1068                    // CRITICAL: In cherry-pick, OURS=base branch, THEIRS=commit being applied
1069                    // We must keep the commit's changes (THEIRS), not the base (OURS)
1070                    // Otherwise we delete the user's code!
1071                    Ok(Some(conflict.their_content.clone()))
1072                } else {
1073                    // Content differs beyond whitespace - not safe to auto-resolve
1074                    debug!(
1075                        "Whitespace conflict has content differences - requires manual resolution"
1076                    );
1077                    Ok(None)
1078                }
1079            }
1080            ConflictType::LineEnding => {
1081                // Normalize to Unix line endings
1082                let normalized = conflict
1083                    .our_content
1084                    .replace("\r\n", "\n")
1085                    .replace('\r', "\n");
1086                Ok(Some(normalized))
1087            }
1088            ConflictType::PureAddition => {
1089                // CRITICAL: In cherry-pick, OURS=base, THEIRS=commit being applied
1090                // We must respect what the commit does (THEIRS), not what the base has (OURS)
1091
1092                if conflict.our_content.is_empty() && !conflict.their_content.is_empty() {
1093                    // Base is empty, commit adds content โ†’ keep the addition
1094                    Ok(Some(conflict.their_content.clone()))
1095                } else if conflict.their_content.is_empty() && !conflict.our_content.is_empty() {
1096                    // Base has content, commit removes it โ†’ keep it removed (empty)
1097                    Ok(Some(String::new()))
1098                } else if conflict.our_content.is_empty() && conflict.their_content.is_empty() {
1099                    // Both empty โ†’ keep empty
1100                    Ok(Some(String::new()))
1101                } else {
1102                    // Both sides have content - this could be:
1103                    // - Duplicate function definitions
1104                    // - Conflicting logic
1105                    // - Different implementations of same feature
1106                    // Too risky to auto-merge - require manual resolution
1107                    debug!(
1108                        "PureAddition conflict has content on both sides - requires manual resolution"
1109                    );
1110                    Ok(None)
1111                }
1112            }
1113            ConflictType::ImportMerge => {
1114                // SAFETY: Only merge simple single-line imports
1115                // Multi-line imports or complex cases require manual resolution
1116
1117                // Check if all imports are single-line and look like imports
1118                let our_lines: Vec<&str> = conflict.our_content.lines().collect();
1119                let their_lines: Vec<&str> = conflict.their_content.lines().collect();
1120
1121                // Verify all lines look like simple imports (heuristic check)
1122                let all_simple = our_lines.iter().chain(their_lines.iter()).all(|line| {
1123                    let trimmed = line.trim();
1124                    trimmed.starts_with("import ")
1125                        || trimmed.starts_with("from ")
1126                        || trimmed.starts_with("use ")
1127                        || trimmed.starts_with("#include")
1128                        || trimmed.is_empty()
1129                });
1130
1131                if !all_simple {
1132                    debug!("ImportMerge contains non-import lines - requires manual resolution");
1133                    return Ok(None);
1134                }
1135
1136                // Merge and deduplicate imports
1137                let mut all_imports: Vec<&str> = our_lines
1138                    .into_iter()
1139                    .chain(their_lines)
1140                    .filter(|line| !line.trim().is_empty())
1141                    .collect();
1142                all_imports.sort();
1143                all_imports.dedup();
1144                Ok(Some(all_imports.join("\n")))
1145            }
1146            ConflictType::Structural | ConflictType::ContentOverlap | ConflictType::Complex => {
1147                // These require manual resolution
1148                Ok(None)
1149            }
1150        }
1151    }
1152
1153    /// Parse conflict markers from file content
1154    fn parse_conflict_markers(&self, content: &str) -> Result<Vec<ConflictRegion>> {
1155        let lines: Vec<&str> = content.lines().collect();
1156        let mut conflicts = Vec::new();
1157        let mut i = 0;
1158
1159        while i < lines.len() {
1160            if lines[i].starts_with("<<<<<<<") {
1161                // Found start of conflict
1162                let start_line = i + 1;
1163                let mut separator_line = None;
1164                let mut end_line = None;
1165
1166                // Find the separator and end
1167                for (j, line) in lines.iter().enumerate().skip(i + 1) {
1168                    if line.starts_with("=======") {
1169                        separator_line = Some(j + 1);
1170                    } else if line.starts_with(">>>>>>>") {
1171                        end_line = Some(j + 1);
1172                        break;
1173                    }
1174                }
1175
1176                if let (Some(sep), Some(end)) = (separator_line, end_line) {
1177                    // Calculate byte positions
1178                    let start_pos = lines[..i].iter().map(|l| l.len() + 1).sum::<usize>();
1179                    let end_pos = lines[..end].iter().map(|l| l.len() + 1).sum::<usize>();
1180
1181                    let our_content = lines[(i + 1)..(sep - 1)].join("\n");
1182                    let their_content = lines[sep..(end - 1)].join("\n");
1183
1184                    conflicts.push(ConflictRegion {
1185                        start: start_pos,
1186                        end: end_pos,
1187                        start_line,
1188                        end_line: end,
1189                        our_content,
1190                        their_content,
1191                    });
1192
1193                    i = end;
1194                } else {
1195                    i += 1;
1196                }
1197            } else {
1198                i += 1;
1199            }
1200        }
1201
1202        Ok(conflicts)
1203    }
1204
1205    /// Update a stack entry with new commit information
1206    /// NOTE: We keep the original branch name to preserve PR mapping, only update commit hash
1207    fn update_stack_entry(
1208        &mut self,
1209        stack_id: Uuid,
1210        entry_id: &Uuid,
1211        _new_branch: &str,
1212        new_commit_hash: &str,
1213    ) -> Result<()> {
1214        debug!(
1215            "Updating entry {} in stack {} with new commit {}",
1216            entry_id, stack_id, new_commit_hash
1217        );
1218
1219        // Get the stack and update the entry
1220        let stack = self
1221            .stack_manager
1222            .get_stack_mut(&stack_id)
1223            .ok_or_else(|| CascadeError::config(format!("Stack {stack_id} not found")))?;
1224
1225        // Find and update the entry
1226        if let Some(entry) = stack.entries.iter_mut().find(|e| e.id == *entry_id) {
1227            debug!(
1228                "Found entry {} - updating commit from '{}' to '{}' (keeping original branch '{}')",
1229                entry_id, entry.commit_hash, new_commit_hash, entry.branch
1230            );
1231
1232            // CRITICAL: Keep the original branch name to preserve PR mapping
1233            // Only update the commit hash to point to the new rebased commit
1234            entry.commit_hash = new_commit_hash.to_string();
1235
1236            // Note: Stack will be saved by the caller (StackManager) after rebase completes
1237
1238            debug!(
1239                "Successfully updated entry {} in stack {}",
1240                entry_id, stack_id
1241            );
1242            Ok(())
1243        } else {
1244            Err(CascadeError::config(format!(
1245                "Entry {entry_id} not found in stack {stack_id}"
1246            )))
1247        }
1248    }
1249
1250    /// Pull latest changes from remote
1251    fn pull_latest_changes(&self, branch: &str) -> Result<()> {
1252        info!("Pulling latest changes for branch {}", branch);
1253
1254        // First try to fetch (this might fail if no remote exists)
1255        match self.git_repo.fetch() {
1256            Ok(_) => {
1257                debug!("Fetch successful");
1258                // Now try to pull the specific branch
1259                match self.git_repo.pull(branch) {
1260                    Ok(_) => {
1261                        info!("Pull completed successfully for {}", branch);
1262                        Ok(())
1263                    }
1264                    Err(e) => {
1265                        warn!("Pull failed for {}: {}", branch, e);
1266                        // Don't fail the entire rebase for pull issues
1267                        Ok(())
1268                    }
1269                }
1270            }
1271            Err(e) => {
1272                warn!("Fetch failed: {}", e);
1273                // Don't fail if there's no remote configured
1274                Ok(())
1275            }
1276        }
1277    }
1278
1279    /// Check if rebase is in progress
1280    pub fn is_rebase_in_progress(&self) -> bool {
1281        // Check for git rebase state files
1282        let git_dir = self.git_repo.path().join(".git");
1283        git_dir.join("REBASE_HEAD").exists()
1284            || git_dir.join("rebase-merge").exists()
1285            || git_dir.join("rebase-apply").exists()
1286    }
1287
1288    /// Abort an in-progress rebase
1289    pub fn abort_rebase(&self) -> Result<()> {
1290        info!("Aborting rebase operation");
1291
1292        let git_dir = self.git_repo.path().join(".git");
1293
1294        // Clean up rebase state files
1295        if git_dir.join("REBASE_HEAD").exists() {
1296            std::fs::remove_file(git_dir.join("REBASE_HEAD")).map_err(|e| {
1297                CascadeError::Git(git2::Error::from_str(&format!(
1298                    "Failed to clean rebase state: {e}"
1299                )))
1300            })?;
1301        }
1302
1303        if git_dir.join("rebase-merge").exists() {
1304            std::fs::remove_dir_all(git_dir.join("rebase-merge")).map_err(|e| {
1305                CascadeError::Git(git2::Error::from_str(&format!(
1306                    "Failed to clean rebase-merge: {e}"
1307                )))
1308            })?;
1309        }
1310
1311        if git_dir.join("rebase-apply").exists() {
1312            std::fs::remove_dir_all(git_dir.join("rebase-apply")).map_err(|e| {
1313                CascadeError::Git(git2::Error::from_str(&format!(
1314                    "Failed to clean rebase-apply: {e}"
1315                )))
1316            })?;
1317        }
1318
1319        info!("Rebase aborted successfully");
1320        Ok(())
1321    }
1322
1323    /// Continue an in-progress rebase after conflict resolution
1324    pub fn continue_rebase(&self) -> Result<()> {
1325        info!("Continuing rebase operation");
1326
1327        // Check if there are still conflicts
1328        if self.git_repo.has_conflicts()? {
1329            return Err(CascadeError::branch(
1330                "Cannot continue rebase: there are unresolved conflicts. Resolve conflicts and stage files first.".to_string()
1331            ));
1332        }
1333
1334        // Stage resolved files
1335        self.git_repo.stage_conflict_resolved_files()?;
1336
1337        info!("Rebase continued successfully");
1338        Ok(())
1339    }
1340
1341    /// Check if there's an in-progress cherry-pick operation
1342    fn has_in_progress_cherry_pick(&self) -> Result<bool> {
1343        let git_dir = self.git_repo.path().join(".git");
1344        Ok(git_dir.join("CHERRY_PICK_HEAD").exists())
1345    }
1346
1347    /// Handle resuming an in-progress cherry-pick from a previous failed sync
1348    fn handle_in_progress_cherry_pick(&mut self, stack: &Stack) -> Result<RebaseResult> {
1349        use crate::cli::output::Output;
1350
1351        let git_dir = self.git_repo.path().join(".git");
1352
1353        Output::section("Resuming in-progress sync");
1354        println!();
1355        Output::info("Detected unfinished cherry-pick from previous sync");
1356        println!();
1357
1358        // Check if conflicts are resolved
1359        if self.git_repo.has_conflicts()? {
1360            let conflicted_files = self.git_repo.get_conflicted_files()?;
1361
1362            let result = RebaseResult {
1363                success: false,
1364                branch_mapping: HashMap::new(),
1365                conflicts: conflicted_files.clone(),
1366                new_commits: Vec::new(),
1367                error: Some(format!(
1368                    "Cannot continue: {} file(s) still have unresolved conflicts\n\n\
1369                    MANUAL CONFLICT RESOLUTION REQUIRED\n\
1370                    =====================================\n\n\
1371                    Conflicted files:\n{}\n\n\
1372                    Step 1: Analyze conflicts\n\
1373                    โ†’ Run: ca conflicts\n\
1374                    โ†’ Shows detailed conflict analysis\n\n\
1375                    Step 2: Resolve conflicts in your editor\n\
1376                    โ†’ Open conflicted files and edit them\n\
1377                    โ†’ Remove conflict markers (<<<<<<, ======, >>>>>>)\n\
1378                    โ†’ Keep the code you want\n\
1379                    โ†’ Save the files\n\n\
1380                    Step 3: Mark conflicts as resolved\n\
1381                    โ†’ Run: git add <resolved-files>\n\
1382                    โ†’ Or: git add -A (to stage all resolved files)\n\n\
1383                    Step 4: Complete the sync\n\
1384                    โ†’ Run: ca sync\n\
1385                    โ†’ Cascade will continue from where it left off\n\n\
1386                    Alternative: Abort and start over\n\
1387                    โ†’ Run: git cherry-pick --abort\n\
1388                    โ†’ Then: ca sync (starts fresh)",
1389                    conflicted_files.len(),
1390                    conflicted_files
1391                        .iter()
1392                        .map(|f| format!("  - {}", f))
1393                        .collect::<Vec<_>>()
1394                        .join("\n")
1395                )),
1396                summary: "Sync paused - conflicts need resolution".to_string(),
1397            };
1398
1399            return Ok(result);
1400        }
1401
1402        // Conflicts are resolved - continue the cherry-pick
1403        Output::info("Conflicts resolved, continuing cherry-pick...");
1404
1405        // Stage all resolved files
1406        self.git_repo.stage_conflict_resolved_files()?;
1407
1408        // Complete the cherry-pick by committing
1409        let cherry_pick_msg_file = git_dir.join("CHERRY_PICK_MSG");
1410        let commit_message = if cherry_pick_msg_file.exists() {
1411            std::fs::read_to_string(&cherry_pick_msg_file)
1412                .unwrap_or_else(|_| "Resolved conflicts".to_string())
1413        } else {
1414            "Resolved conflicts".to_string()
1415        };
1416
1417        match self.git_repo.commit(&commit_message) {
1418            Ok(_new_commit_id) => {
1419                Output::success("Cherry-pick completed");
1420
1421                // Clean up cherry-pick state
1422                if git_dir.join("CHERRY_PICK_HEAD").exists() {
1423                    let _ = std::fs::remove_file(git_dir.join("CHERRY_PICK_HEAD"));
1424                }
1425                if cherry_pick_msg_file.exists() {
1426                    let _ = std::fs::remove_file(&cherry_pick_msg_file);
1427                }
1428
1429                println!();
1430                Output::info("Continuing with rest of stack...");
1431                println!();
1432
1433                // Now continue with the rest of the rebase
1434                // We need to restart the full rebase since we don't track which entry we were on
1435                self.rebase_with_force_push(stack)
1436            }
1437            Err(e) => {
1438                let result = RebaseResult {
1439                    success: false,
1440                    branch_mapping: HashMap::new(),
1441                    conflicts: Vec::new(),
1442                    new_commits: Vec::new(),
1443                    error: Some(format!(
1444                        "Failed to complete cherry-pick: {}\n\n\
1445                        This usually means:\n\
1446                        - Git index is locked (another process accessing repo)\n\
1447                        - File permissions issue\n\
1448                        - Disk space issue\n\n\
1449                        Recovery:\n\
1450                        1. Check if another Git operation is running\n\
1451                        2. Run 'rm -f .git/index.lock' if stale lock exists\n\
1452                        3. Run 'git status' to check repo state\n\
1453                        4. Retry 'ca sync' after fixing the issue\n\n\
1454                        Or abort and start fresh:\n\
1455                        โ†’ Run: git cherry-pick --abort\n\
1456                        โ†’ Then: ca sync",
1457                        e
1458                    )),
1459                    summary: "Failed to complete cherry-pick".to_string(),
1460                };
1461
1462                Ok(result)
1463            }
1464        }
1465    }
1466}
1467
1468impl RebaseResult {
1469    /// Get a summary of the rebase operation
1470    pub fn get_summary(&self) -> String {
1471        if self.success {
1472            format!("โœ… {}", self.summary)
1473        } else {
1474            format!(
1475                "โŒ Rebase failed: {}",
1476                self.error.as_deref().unwrap_or("Unknown error")
1477            )
1478        }
1479    }
1480
1481    /// Check if any conflicts occurred
1482    pub fn has_conflicts(&self) -> bool {
1483        !self.conflicts.is_empty()
1484    }
1485
1486    /// Get the number of successful operations
1487    pub fn success_count(&self) -> usize {
1488        self.new_commits.len()
1489    }
1490}
1491
1492#[cfg(test)]
1493mod tests {
1494    use super::*;
1495    use std::path::PathBuf;
1496    use std::process::Command;
1497    use tempfile::TempDir;
1498
1499    #[allow(dead_code)]
1500    fn create_test_repo() -> (TempDir, PathBuf) {
1501        let temp_dir = TempDir::new().unwrap();
1502        let repo_path = temp_dir.path().to_path_buf();
1503
1504        // Initialize git repository
1505        Command::new("git")
1506            .args(["init"])
1507            .current_dir(&repo_path)
1508            .output()
1509            .unwrap();
1510        Command::new("git")
1511            .args(["config", "user.name", "Test"])
1512            .current_dir(&repo_path)
1513            .output()
1514            .unwrap();
1515        Command::new("git")
1516            .args(["config", "user.email", "test@test.com"])
1517            .current_dir(&repo_path)
1518            .output()
1519            .unwrap();
1520
1521        // Create initial commit
1522        std::fs::write(repo_path.join("README.md"), "# Test").unwrap();
1523        Command::new("git")
1524            .args(["add", "."])
1525            .current_dir(&repo_path)
1526            .output()
1527            .unwrap();
1528        Command::new("git")
1529            .args(["commit", "-m", "Initial"])
1530            .current_dir(&repo_path)
1531            .output()
1532            .unwrap();
1533
1534        (temp_dir, repo_path)
1535    }
1536
1537    #[test]
1538    fn test_conflict_region_creation() {
1539        let region = ConflictRegion {
1540            start: 0,
1541            end: 50,
1542            start_line: 1,
1543            end_line: 3,
1544            our_content: "function test() {\n    return true;\n}".to_string(),
1545            their_content: "function test() {\n  return true;\n}".to_string(),
1546        };
1547
1548        assert_eq!(region.start_line, 1);
1549        assert_eq!(region.end_line, 3);
1550        assert!(region.our_content.contains("return true"));
1551        assert!(region.their_content.contains("return true"));
1552    }
1553
1554    #[test]
1555    fn test_rebase_strategies() {
1556        assert_eq!(RebaseStrategy::ForcePush, RebaseStrategy::ForcePush);
1557        assert_eq!(RebaseStrategy::Interactive, RebaseStrategy::Interactive);
1558    }
1559
1560    #[test]
1561    fn test_rebase_options() {
1562        let options = RebaseOptions::default();
1563        assert_eq!(options.strategy, RebaseStrategy::ForcePush);
1564        assert!(!options.interactive);
1565        assert!(options.auto_resolve);
1566        assert_eq!(options.max_retries, 3);
1567    }
1568
1569    #[test]
1570    fn test_cleanup_guard_tracks_branches() {
1571        let mut guard = TempBranchCleanupGuard::new();
1572        assert!(guard.branches.is_empty());
1573
1574        guard.add_branch("test-branch-1".to_string());
1575        guard.add_branch("test-branch-2".to_string());
1576
1577        assert_eq!(guard.branches.len(), 2);
1578        assert_eq!(guard.branches[0], "test-branch-1");
1579        assert_eq!(guard.branches[1], "test-branch-2");
1580    }
1581
1582    #[test]
1583    fn test_cleanup_guard_prevents_double_cleanup() {
1584        use std::process::Command;
1585        use tempfile::TempDir;
1586
1587        // Create a temporary git repo
1588        let temp_dir = TempDir::new().unwrap();
1589        let repo_path = temp_dir.path();
1590
1591        Command::new("git")
1592            .args(["init"])
1593            .current_dir(repo_path)
1594            .output()
1595            .unwrap();
1596
1597        Command::new("git")
1598            .args(["config", "user.name", "Test"])
1599            .current_dir(repo_path)
1600            .output()
1601            .unwrap();
1602
1603        Command::new("git")
1604            .args(["config", "user.email", "test@test.com"])
1605            .current_dir(repo_path)
1606            .output()
1607            .unwrap();
1608
1609        // Create initial commit
1610        std::fs::write(repo_path.join("test.txt"), "test").unwrap();
1611        Command::new("git")
1612            .args(["add", "."])
1613            .current_dir(repo_path)
1614            .output()
1615            .unwrap();
1616        Command::new("git")
1617            .args(["commit", "-m", "initial"])
1618            .current_dir(repo_path)
1619            .output()
1620            .unwrap();
1621
1622        let git_repo = GitRepository::open(repo_path).unwrap();
1623
1624        // Create a test branch
1625        git_repo.create_branch("test-temp", None).unwrap();
1626
1627        let mut guard = TempBranchCleanupGuard::new();
1628        guard.add_branch("test-temp".to_string());
1629
1630        // First cleanup should work
1631        guard.cleanup(&git_repo);
1632        assert!(guard.cleaned);
1633
1634        // Second cleanup should be a no-op (shouldn't panic)
1635        guard.cleanup(&git_repo);
1636        assert!(guard.cleaned);
1637    }
1638
1639    #[test]
1640    fn test_rebase_result() {
1641        let result = RebaseResult {
1642            success: true,
1643            branch_mapping: std::collections::HashMap::new(),
1644            conflicts: vec!["abc123".to_string()],
1645            new_commits: vec!["def456".to_string()],
1646            error: None,
1647            summary: "Test summary".to_string(),
1648        };
1649
1650        assert!(result.success);
1651        assert!(result.has_conflicts());
1652        assert_eq!(result.success_count(), 1);
1653    }
1654}