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                    // SAFETY CHECK: Detect if working branch has commits beyond the last stack entry
614                    // If it does, we need to preserve them - don't force-update the working branch
615                    if let (Ok(working_head), Ok(top_commit)) = (
616                        self.git_repo.get_branch_head(orig_branch),
617                        self.git_repo.get_branch_head(top_branch),
618                    ) {
619                        // Check if working branch is ahead of top stack entry
620                        if working_head != top_commit {
621                            // Get commits between top of stack and working branch head
622                            if let Ok(commits) = self
623                                .git_repo
624                                .get_commits_between(&top_commit, &working_head)
625                            {
626                                if !commits.is_empty() {
627                                    // Working branch has extra commits!
628                                    Output::error(format!(
629                                        "Cannot sync: Working branch '{}' has {} commit(s) not in the stack",
630                                        orig_branch,
631                                        commits.len()
632                                    ));
633                                    println!();
634                                    Output::sub_item("These commits would be lost if we proceed:");
635                                    for (i, commit) in commits.iter().take(5).enumerate() {
636                                        let message = commit.summary().unwrap_or("(no message)");
637                                        Output::sub_item(format!(
638                                            "  {}. {} - {}",
639                                            i + 1,
640                                            &commit.id().to_string()[..8],
641                                            message
642                                        ));
643                                    }
644                                    if commits.len() > 5 {
645                                        Output::sub_item(format!(
646                                            "  ... and {} more",
647                                            commits.len() - 5
648                                        ));
649                                    }
650                                    println!();
651                                    Output::tip("Add these commits to the stack first:");
652                                    Output::bullet("Run: ca stack push");
653                                    Output::bullet("Then run: ca sync");
654                                    println!();
655
656                                    return Err(CascadeError::validation(
657                                        format!(
658                                            "Working branch '{}' has {} untracked commit(s). Add them to the stack with 'ca stack push' before syncing.",
659                                            orig_branch, commits.len()
660                                        )
661                                    ));
662                                }
663                            }
664                        }
665
666                        // Safe to update - working branch matches top of stack or is behind
667                        debug!(
668                            "Updating working branch '{}' to match top of stack ({})",
669                            orig_branch,
670                            &top_commit[..8]
671                        );
672
673                        if let Err(e) = self
674                            .git_repo
675                            .update_branch_to_commit(orig_branch, &top_commit)
676                        {
677                            Output::warning(format!(
678                                "Could not update working branch '{}' to top of stack: {}",
679                                orig_branch, e
680                            ));
681                        }
682                    }
683                }
684
685                // Return to original working branch
686                // Use unsafe checkout to force it (we're in cleanup phase, no uncommitted changes)
687                if let Err(e) = self.git_repo.checkout_branch_unsafe(orig_branch) {
688                    debug!(
689                        "Could not return to original branch '{}': {}",
690                        orig_branch, e
691                    );
692                    // Non-critical: User is left on base branch instead of working branch
693                }
694            } else {
695                // User was on base branch - this is unusual but valid
696                // Don't update base branch, just checkout back to it
697                debug!(
698                    "Skipping working branch update - user was on base branch '{}'",
699                    orig_branch
700                );
701                if let Err(e) = self.git_repo.checkout_branch_unsafe(orig_branch) {
702                    debug!("Could not return to base branch '{}': {}", orig_branch, e);
703                }
704            }
705        }
706
707        // Build summary message
708        result.summary = if pushed_count > 0 {
709            let pr_plural = if pushed_count == 1 { "" } else { "s" };
710            let entry_plural = if entry_count == 1 { "entry" } else { "entries" };
711
712            if skipped_count > 0 {
713                format!(
714                    "{} {} rebased ({} PR{} updated, {} not yet submitted)",
715                    entry_count, entry_plural, pushed_count, pr_plural, skipped_count
716                )
717            } else {
718                format!(
719                    "{} {} rebased ({} PR{} updated)",
720                    entry_count, entry_plural, pushed_count, pr_plural
721                )
722            }
723        } else {
724            let plural = if entry_count == 1 { "entry" } else { "entries" };
725            format!("{} {} rebased (no PRs to update yet)", entry_count, plural)
726        };
727
728        // Display result with proper formatting
729        println!(); // Spacing after tree
730        if result.success {
731            Output::success(&result.summary);
732        } else {
733            // Display error with proper icon
734            let error_msg = result
735                .error
736                .as_deref()
737                .unwrap_or("Rebase failed for unknown reason");
738            Output::error(error_msg);
739        }
740
741        // Save the updated stack metadata to disk
742        self.stack_manager.save_to_disk()?;
743
744        // CRITICAL: Return error if rebase failed
745        // Don't return Ok(result) with result.success = false - that's confusing!
746        if !result.success {
747            // Include the detailed error message (which contains conflict info)
748            let detailed_error = result.error.as_deref().unwrap_or("Rebase failed");
749            return Err(CascadeError::Branch(detailed_error.to_string()));
750        }
751
752        Ok(result)
753    }
754
755    /// Interactive rebase with user input
756    fn rebase_interactive(&mut self, stack: &Stack) -> Result<RebaseResult> {
757        info!("Starting interactive rebase for stack '{}'", stack.name);
758
759        let mut result = RebaseResult {
760            success: true,
761            branch_mapping: HashMap::new(),
762            conflicts: Vec::new(),
763            new_commits: Vec::new(),
764            error: None,
765            summary: String::new(),
766        };
767
768        println!("Interactive Rebase for Stack: {}", stack.name);
769        println!("   Base branch: {}", stack.base_branch);
770        println!("   Entries: {}", stack.entries.len());
771
772        if self.options.interactive {
773            println!("\nChoose action for each commit:");
774            println!("  (p)ick   - apply the commit");
775            println!("  (s)kip   - skip this commit");
776            println!("  (e)dit   - edit the commit message");
777            println!("  (q)uit   - abort the rebase");
778        }
779
780        // For now, automatically pick all commits
781        // In a real implementation, this would prompt the user
782        for entry in &stack.entries {
783            println!(
784                "  {} {} - {}",
785                entry.short_hash(),
786                entry.branch,
787                entry.short_message(50)
788            );
789
790            // Auto-pick for demo purposes
791            match self.cherry_pick_commit(&entry.commit_hash) {
792                Ok(new_commit) => result.new_commits.push(new_commit),
793                Err(_) => result.conflicts.push(entry.commit_hash.clone()),
794            }
795        }
796
797        result.summary = format!(
798            "Interactive rebase processed {} commits",
799            stack.entries.len()
800        );
801        Ok(result)
802    }
803
804    /// Cherry-pick a commit onto the current branch
805    fn cherry_pick_commit(&self, commit_hash: &str) -> Result<String> {
806        // Use the real cherry-pick implementation from GitRepository
807        let new_commit_hash = self.git_repo.cherry_pick(commit_hash)?;
808
809        // Check for any leftover staged changes after successful cherry-pick
810        if let Ok(staged_files) = self.git_repo.get_staged_files() {
811            if !staged_files.is_empty() {
812                // Commit any leftover staged changes silently
813                let cleanup_message = format!("Cleanup after cherry-pick {}", &commit_hash[..8]);
814                let _ = self.git_repo.commit_staged_changes(&cleanup_message);
815            }
816        }
817
818        Ok(new_commit_hash)
819    }
820
821    /// Attempt to automatically resolve conflicts
822    fn auto_resolve_conflicts(&self, commit_hash: &str) -> Result<bool> {
823        debug!("Starting auto-resolve for commit {}", commit_hash);
824
825        // Check if there are actually conflicts
826        let has_conflicts = self.git_repo.has_conflicts()?;
827        debug!("has_conflicts() = {}", has_conflicts);
828
829        // Check if cherry-pick is in progress
830        let cherry_pick_head = self.git_repo.path().join(".git").join("CHERRY_PICK_HEAD");
831        let cherry_pick_in_progress = cherry_pick_head.exists();
832
833        if !has_conflicts {
834            debug!("No conflicts detected by Git index");
835
836            // If cherry-pick is in progress but no conflicts detected, something is wrong
837            if cherry_pick_in_progress {
838                warn!("CHERRY_PICK_HEAD exists but no conflicts in index - aborting cherry-pick");
839
840                // Abort the cherry-pick to clean up
841                let _ = std::process::Command::new("git")
842                    .args(["cherry-pick", "--abort"])
843                    .current_dir(self.git_repo.path())
844                    .output();
845
846                return Err(CascadeError::Branch(format!(
847                    "Cherry-pick failed for {} but Git index shows no conflicts. \
848                     This usually means the cherry-pick was aborted or failed in an unexpected way. \
849                     Please try manual resolution.",
850                    &commit_hash[..8]
851                )));
852            }
853
854            return Ok(true);
855        }
856
857        let conflicted_files = self.git_repo.get_conflicted_files()?;
858
859        if conflicted_files.is_empty() {
860            debug!("Conflicted files list is empty");
861            return Ok(true);
862        }
863
864        debug!(
865            "Found conflicts in {} files: {:?}",
866            conflicted_files.len(),
867            conflicted_files
868        );
869
870        // Use the new conflict analyzer for detailed analysis
871        let analysis = self
872            .conflict_analyzer
873            .analyze_conflicts(&conflicted_files, self.git_repo.path())?;
874
875        debug!(
876            "Conflict analysis: {} total conflicts, {} auto-resolvable",
877            analysis.total_conflicts, analysis.auto_resolvable_count
878        );
879
880        // Display recommendations
881        for recommendation in &analysis.recommendations {
882            debug!("{}", recommendation);
883        }
884
885        let mut resolved_count = 0;
886        let mut resolved_files = Vec::new(); // Track which files were actually resolved
887        let mut failed_files = Vec::new();
888
889        for file_analysis in &analysis.files {
890            debug!(
891                "Processing file: {} (auto_resolvable: {}, conflicts: {})",
892                file_analysis.file_path,
893                file_analysis.auto_resolvable,
894                file_analysis.conflicts.len()
895            );
896
897            if file_analysis.auto_resolvable {
898                match self.resolve_file_conflicts_enhanced(
899                    &file_analysis.file_path,
900                    &file_analysis.conflicts,
901                ) {
902                    Ok(ConflictResolution::Resolved) => {
903                        resolved_count += 1;
904                        resolved_files.push(file_analysis.file_path.clone());
905                        debug!("Successfully resolved {}", file_analysis.file_path);
906                    }
907                    Ok(ConflictResolution::TooComplex) => {
908                        debug!(
909                            "{} too complex for auto-resolution",
910                            file_analysis.file_path
911                        );
912                        failed_files.push(file_analysis.file_path.clone());
913                    }
914                    Err(e) => {
915                        debug!("Failed to resolve {}: {}", file_analysis.file_path, e);
916                        failed_files.push(file_analysis.file_path.clone());
917                    }
918                }
919            } else {
920                failed_files.push(file_analysis.file_path.clone());
921                debug!(
922                    "{} requires manual resolution ({} conflicts)",
923                    file_analysis.file_path,
924                    file_analysis.conflicts.len()
925                );
926            }
927        }
928
929        if resolved_count > 0 {
930            debug!(
931                "Resolved {}/{} files",
932                resolved_count,
933                conflicted_files.len()
934            );
935            debug!("Resolved files: {:?}", resolved_files);
936
937            // CRITICAL: Only stage files that were successfully resolved
938            // This prevents staging files that still have conflict markers
939            let file_paths: Vec<&str> = resolved_files.iter().map(|s| s.as_str()).collect();
940            debug!("Staging {} files", file_paths.len());
941            self.git_repo.stage_files(&file_paths)?;
942            debug!("Files staged successfully");
943        } else {
944            debug!("No files were resolved (resolved_count = 0)");
945        }
946
947        // Return true only if ALL conflicts were resolved
948        let all_resolved = failed_files.is_empty();
949
950        debug!(
951            "all_resolved = {}, failed_files = {:?}",
952            all_resolved, failed_files
953        );
954
955        if !all_resolved {
956            debug!("{} files still need manual resolution", failed_files.len());
957        }
958
959        debug!("Returning all_resolved = {}", all_resolved);
960        Ok(all_resolved)
961    }
962
963    /// Resolve conflicts using enhanced analysis
964    fn resolve_file_conflicts_enhanced(
965        &self,
966        file_path: &str,
967        conflicts: &[crate::git::ConflictRegion],
968    ) -> Result<ConflictResolution> {
969        let repo_path = self.git_repo.path();
970        let full_path = repo_path.join(file_path);
971
972        // Read the file content with conflict markers
973        let mut content = std::fs::read_to_string(&full_path)
974            .map_err(|e| CascadeError::config(format!("Failed to read file {file_path}: {e}")))?;
975
976        if conflicts.is_empty() {
977            return Ok(ConflictResolution::Resolved);
978        }
979
980        info!(
981            "Resolving {} conflicts in {} using enhanced analysis",
982            conflicts.len(),
983            file_path
984        );
985
986        let mut any_resolved = false;
987
988        // Process conflicts in reverse order to maintain string indices
989        for conflict in conflicts.iter().rev() {
990            match self.resolve_single_conflict_enhanced(conflict) {
991                Ok(Some(resolution)) => {
992                    // Replace the conflict region with the resolved content
993                    let before = &content[..conflict.start_pos];
994                    let after = &content[conflict.end_pos..];
995                    content = format!("{before}{resolution}{after}");
996                    any_resolved = true;
997                    debug!(
998                        "โœ… Resolved {} conflict at lines {}-{} in {}",
999                        format!("{:?}", conflict.conflict_type).to_lowercase(),
1000                        conflict.start_line,
1001                        conflict.end_line,
1002                        file_path
1003                    );
1004                }
1005                Ok(None) => {
1006                    debug!(
1007                        "โš ๏ธ  {} conflict at lines {}-{} in {} requires manual resolution",
1008                        format!("{:?}", conflict.conflict_type).to_lowercase(),
1009                        conflict.start_line,
1010                        conflict.end_line,
1011                        file_path
1012                    );
1013                    return Ok(ConflictResolution::TooComplex);
1014                }
1015                Err(e) => {
1016                    debug!("โŒ Failed to resolve conflict in {}: {}", file_path, e);
1017                    return Ok(ConflictResolution::TooComplex);
1018                }
1019            }
1020        }
1021
1022        if any_resolved {
1023            // Check if we resolved ALL conflicts in this file
1024            let remaining_conflicts = self.parse_conflict_markers(&content)?;
1025
1026            if remaining_conflicts.is_empty() {
1027                debug!(
1028                    "All conflicts resolved in {}, content length: {} bytes",
1029                    file_path,
1030                    content.len()
1031                );
1032
1033                // CRITICAL SAFETY CHECK: Don't write empty files!
1034                if content.trim().is_empty() {
1035                    warn!(
1036                        "SAFETY CHECK: Resolved content for {} is empty! Aborting auto-resolution.",
1037                        file_path
1038                    );
1039                    return Ok(ConflictResolution::TooComplex);
1040                }
1041
1042                // SAFETY: Create backup before writing resolved content
1043                let backup_path = full_path.with_extension("cascade-backup");
1044                if let Ok(original_content) = std::fs::read_to_string(&full_path) {
1045                    debug!(
1046                        "Backup for {} (original: {} bytes, resolved: {} bytes)",
1047                        file_path,
1048                        original_content.len(),
1049                        content.len()
1050                    );
1051                    let _ = std::fs::write(&backup_path, original_content);
1052                }
1053
1054                // All conflicts resolved - write the file back atomically
1055                crate::utils::atomic_file::write_string(&full_path, &content)?;
1056
1057                debug!("Wrote {} bytes to {}", content.len(), file_path);
1058                return Ok(ConflictResolution::Resolved);
1059            } else {
1060                info!(
1061                    "Partially resolved conflicts in {} ({} remaining)",
1062                    file_path,
1063                    remaining_conflicts.len()
1064                );
1065            }
1066        }
1067
1068        Ok(ConflictResolution::TooComplex)
1069    }
1070
1071    /// Helper to count whitespace consistency (lower is better)
1072    #[allow(dead_code)]
1073    fn count_whitespace_consistency(content: &str) -> usize {
1074        let mut inconsistencies = 0;
1075        let lines: Vec<&str> = content.lines().collect();
1076
1077        for line in &lines {
1078            // Check for mixed tabs and spaces
1079            if line.contains('\t') && line.contains(' ') {
1080                inconsistencies += 1;
1081            }
1082        }
1083
1084        // Penalize for inconsistencies
1085        lines.len().saturating_sub(inconsistencies)
1086    }
1087
1088    /// Resolve a single conflict using enhanced analysis
1089    fn resolve_single_conflict_enhanced(
1090        &self,
1091        conflict: &crate::git::ConflictRegion,
1092    ) -> Result<Option<String>> {
1093        debug!(
1094            "Resolving {} conflict in {} (lines {}-{})",
1095            format!("{:?}", conflict.conflict_type).to_lowercase(),
1096            conflict.file_path,
1097            conflict.start_line,
1098            conflict.end_line
1099        );
1100
1101        use crate::git::ConflictType;
1102
1103        match conflict.conflict_type {
1104            ConflictType::Whitespace => {
1105                // SAFETY: Only resolve if the content is truly identical except for whitespace
1106                // Otherwise, it might be intentional formatting changes
1107                let our_normalized = conflict
1108                    .our_content
1109                    .split_whitespace()
1110                    .collect::<Vec<_>>()
1111                    .join(" ");
1112                let their_normalized = conflict
1113                    .their_content
1114                    .split_whitespace()
1115                    .collect::<Vec<_>>()
1116                    .join(" ");
1117
1118                if our_normalized == their_normalized {
1119                    // Content is identical - in cherry-pick context, ALWAYS prefer THEIRS
1120                    // CRITICAL: In cherry-pick, OURS=base branch, THEIRS=commit being applied
1121                    // We must keep the commit's changes (THEIRS), not the base (OURS)
1122                    // Otherwise we delete the user's code!
1123                    Ok(Some(conflict.their_content.clone()))
1124                } else {
1125                    // Content differs beyond whitespace - not safe to auto-resolve
1126                    debug!(
1127                        "Whitespace conflict has content differences - requires manual resolution"
1128                    );
1129                    Ok(None)
1130                }
1131            }
1132            ConflictType::LineEnding => {
1133                // Normalize to Unix line endings
1134                let normalized = conflict
1135                    .our_content
1136                    .replace("\r\n", "\n")
1137                    .replace('\r', "\n");
1138                Ok(Some(normalized))
1139            }
1140            ConflictType::PureAddition => {
1141                // CRITICAL: In cherry-pick, OURS=base, THEIRS=commit being applied
1142                // We must respect what the commit does (THEIRS), not what the base has (OURS)
1143
1144                if conflict.our_content.is_empty() && !conflict.their_content.is_empty() {
1145                    // Base is empty, commit adds content โ†’ keep the addition
1146                    Ok(Some(conflict.their_content.clone()))
1147                } else if conflict.their_content.is_empty() && !conflict.our_content.is_empty() {
1148                    // Base has content, commit removes it โ†’ keep it removed (empty)
1149                    Ok(Some(String::new()))
1150                } else if conflict.our_content.is_empty() && conflict.their_content.is_empty() {
1151                    // Both empty โ†’ keep empty
1152                    Ok(Some(String::new()))
1153                } else {
1154                    // Both sides have content - this could be:
1155                    // - Duplicate function definitions
1156                    // - Conflicting logic
1157                    // - Different implementations of same feature
1158                    // Too risky to auto-merge - require manual resolution
1159                    debug!(
1160                        "PureAddition conflict has content on both sides - requires manual resolution"
1161                    );
1162                    Ok(None)
1163                }
1164            }
1165            ConflictType::ImportMerge => {
1166                // SAFETY: Only merge simple single-line imports
1167                // Multi-line imports or complex cases require manual resolution
1168
1169                // Check if all imports are single-line and look like imports
1170                let our_lines: Vec<&str> = conflict.our_content.lines().collect();
1171                let their_lines: Vec<&str> = conflict.their_content.lines().collect();
1172
1173                // Verify all lines look like simple imports (heuristic check)
1174                let all_simple = our_lines.iter().chain(their_lines.iter()).all(|line| {
1175                    let trimmed = line.trim();
1176                    trimmed.starts_with("import ")
1177                        || trimmed.starts_with("from ")
1178                        || trimmed.starts_with("use ")
1179                        || trimmed.starts_with("#include")
1180                        || trimmed.is_empty()
1181                });
1182
1183                if !all_simple {
1184                    debug!("ImportMerge contains non-import lines - requires manual resolution");
1185                    return Ok(None);
1186                }
1187
1188                // Merge and deduplicate imports
1189                let mut all_imports: Vec<&str> = our_lines
1190                    .into_iter()
1191                    .chain(their_lines)
1192                    .filter(|line| !line.trim().is_empty())
1193                    .collect();
1194                all_imports.sort();
1195                all_imports.dedup();
1196                Ok(Some(all_imports.join("\n")))
1197            }
1198            ConflictType::Structural | ConflictType::ContentOverlap | ConflictType::Complex => {
1199                // These require manual resolution
1200                Ok(None)
1201            }
1202        }
1203    }
1204
1205    /// Parse conflict markers from file content
1206    fn parse_conflict_markers(&self, content: &str) -> Result<Vec<ConflictRegion>> {
1207        let lines: Vec<&str> = content.lines().collect();
1208        let mut conflicts = Vec::new();
1209        let mut i = 0;
1210
1211        while i < lines.len() {
1212            if lines[i].starts_with("<<<<<<<") {
1213                // Found start of conflict
1214                let start_line = i + 1;
1215                let mut separator_line = None;
1216                let mut end_line = None;
1217
1218                // Find the separator and end
1219                for (j, line) in lines.iter().enumerate().skip(i + 1) {
1220                    if line.starts_with("=======") {
1221                        separator_line = Some(j + 1);
1222                    } else if line.starts_with(">>>>>>>") {
1223                        end_line = Some(j + 1);
1224                        break;
1225                    }
1226                }
1227
1228                if let (Some(sep), Some(end)) = (separator_line, end_line) {
1229                    // Calculate byte positions
1230                    let start_pos = lines[..i].iter().map(|l| l.len() + 1).sum::<usize>();
1231                    let end_pos = lines[..end].iter().map(|l| l.len() + 1).sum::<usize>();
1232
1233                    let our_content = lines[(i + 1)..(sep - 1)].join("\n");
1234                    let their_content = lines[sep..(end - 1)].join("\n");
1235
1236                    conflicts.push(ConflictRegion {
1237                        start: start_pos,
1238                        end: end_pos,
1239                        start_line,
1240                        end_line: end,
1241                        our_content,
1242                        their_content,
1243                    });
1244
1245                    i = end;
1246                } else {
1247                    i += 1;
1248                }
1249            } else {
1250                i += 1;
1251            }
1252        }
1253
1254        Ok(conflicts)
1255    }
1256
1257    /// Update a stack entry with new commit information
1258    /// NOTE: We keep the original branch name to preserve PR mapping, only update commit hash
1259    fn update_stack_entry(
1260        &mut self,
1261        stack_id: Uuid,
1262        entry_id: &Uuid,
1263        _new_branch: &str,
1264        new_commit_hash: &str,
1265    ) -> Result<()> {
1266        debug!(
1267            "Updating entry {} in stack {} with new commit {}",
1268            entry_id, stack_id, new_commit_hash
1269        );
1270
1271        // Get the stack and update the entry
1272        let stack = self
1273            .stack_manager
1274            .get_stack_mut(&stack_id)
1275            .ok_or_else(|| CascadeError::config(format!("Stack {stack_id} not found")))?;
1276
1277        // Find and update the entry
1278        if let Some(entry) = stack.entries.iter_mut().find(|e| e.id == *entry_id) {
1279            debug!(
1280                "Found entry {} - updating commit from '{}' to '{}' (keeping original branch '{}')",
1281                entry_id, entry.commit_hash, new_commit_hash, entry.branch
1282            );
1283
1284            // CRITICAL: Keep the original branch name to preserve PR mapping
1285            // Only update the commit hash to point to the new rebased commit
1286            entry.commit_hash = new_commit_hash.to_string();
1287
1288            // Note: Stack will be saved by the caller (StackManager) after rebase completes
1289
1290            debug!(
1291                "Successfully updated entry {} in stack {}",
1292                entry_id, stack_id
1293            );
1294            Ok(())
1295        } else {
1296            Err(CascadeError::config(format!(
1297                "Entry {entry_id} not found in stack {stack_id}"
1298            )))
1299        }
1300    }
1301
1302    /// Pull latest changes from remote
1303    fn pull_latest_changes(&self, branch: &str) -> Result<()> {
1304        info!("Pulling latest changes for branch {}", branch);
1305
1306        // First try to fetch (this might fail if no remote exists)
1307        match self.git_repo.fetch() {
1308            Ok(_) => {
1309                debug!("Fetch successful");
1310                // Now try to pull the specific branch
1311                match self.git_repo.pull(branch) {
1312                    Ok(_) => {
1313                        info!("Pull completed successfully for {}", branch);
1314                        Ok(())
1315                    }
1316                    Err(e) => {
1317                        warn!("Pull failed for {}: {}", branch, e);
1318                        // Don't fail the entire rebase for pull issues
1319                        Ok(())
1320                    }
1321                }
1322            }
1323            Err(e) => {
1324                warn!("Fetch failed: {}", e);
1325                // Don't fail if there's no remote configured
1326                Ok(())
1327            }
1328        }
1329    }
1330
1331    /// Check if rebase is in progress
1332    pub fn is_rebase_in_progress(&self) -> bool {
1333        // Check for git rebase state files
1334        let git_dir = self.git_repo.path().join(".git");
1335        git_dir.join("REBASE_HEAD").exists()
1336            || git_dir.join("rebase-merge").exists()
1337            || git_dir.join("rebase-apply").exists()
1338    }
1339
1340    /// Abort an in-progress rebase
1341    pub fn abort_rebase(&self) -> Result<()> {
1342        info!("Aborting rebase operation");
1343
1344        let git_dir = self.git_repo.path().join(".git");
1345
1346        // Clean up rebase state files
1347        if git_dir.join("REBASE_HEAD").exists() {
1348            std::fs::remove_file(git_dir.join("REBASE_HEAD")).map_err(|e| {
1349                CascadeError::Git(git2::Error::from_str(&format!(
1350                    "Failed to clean rebase state: {e}"
1351                )))
1352            })?;
1353        }
1354
1355        if git_dir.join("rebase-merge").exists() {
1356            std::fs::remove_dir_all(git_dir.join("rebase-merge")).map_err(|e| {
1357                CascadeError::Git(git2::Error::from_str(&format!(
1358                    "Failed to clean rebase-merge: {e}"
1359                )))
1360            })?;
1361        }
1362
1363        if git_dir.join("rebase-apply").exists() {
1364            std::fs::remove_dir_all(git_dir.join("rebase-apply")).map_err(|e| {
1365                CascadeError::Git(git2::Error::from_str(&format!(
1366                    "Failed to clean rebase-apply: {e}"
1367                )))
1368            })?;
1369        }
1370
1371        info!("Rebase aborted successfully");
1372        Ok(())
1373    }
1374
1375    /// Continue an in-progress rebase after conflict resolution
1376    pub fn continue_rebase(&self) -> Result<()> {
1377        info!("Continuing rebase operation");
1378
1379        // Check if there are still conflicts
1380        if self.git_repo.has_conflicts()? {
1381            return Err(CascadeError::branch(
1382                "Cannot continue rebase: there are unresolved conflicts. Resolve conflicts and stage files first.".to_string()
1383            ));
1384        }
1385
1386        // Stage resolved files
1387        self.git_repo.stage_conflict_resolved_files()?;
1388
1389        info!("Rebase continued successfully");
1390        Ok(())
1391    }
1392
1393    /// Check if there's an in-progress cherry-pick operation
1394    fn has_in_progress_cherry_pick(&self) -> Result<bool> {
1395        let git_dir = self.git_repo.path().join(".git");
1396        Ok(git_dir.join("CHERRY_PICK_HEAD").exists())
1397    }
1398
1399    /// Handle resuming an in-progress cherry-pick from a previous failed sync
1400    fn handle_in_progress_cherry_pick(&mut self, stack: &Stack) -> Result<RebaseResult> {
1401        use crate::cli::output::Output;
1402
1403        let git_dir = self.git_repo.path().join(".git");
1404
1405        Output::section("Resuming in-progress sync");
1406        println!();
1407        Output::info("Detected unfinished cherry-pick from previous sync");
1408        println!();
1409
1410        // Check if conflicts are resolved
1411        if self.git_repo.has_conflicts()? {
1412            let conflicted_files = self.git_repo.get_conflicted_files()?;
1413
1414            let result = RebaseResult {
1415                success: false,
1416                branch_mapping: HashMap::new(),
1417                conflicts: conflicted_files.clone(),
1418                new_commits: Vec::new(),
1419                error: Some(format!(
1420                    "Cannot continue: {} file(s) still have unresolved conflicts\n\n\
1421                    MANUAL CONFLICT RESOLUTION REQUIRED\n\
1422                    =====================================\n\n\
1423                    Conflicted files:\n{}\n\n\
1424                    Step 1: Analyze conflicts\n\
1425                    โ†’ Run: ca conflicts\n\
1426                    โ†’ Shows detailed conflict analysis\n\n\
1427                    Step 2: Resolve conflicts in your editor\n\
1428                    โ†’ Open conflicted files and edit them\n\
1429                    โ†’ Remove conflict markers (<<<<<<, ======, >>>>>>)\n\
1430                    โ†’ Keep the code you want\n\
1431                    โ†’ Save the files\n\n\
1432                    Step 3: Mark conflicts as resolved\n\
1433                    โ†’ Run: git add <resolved-files>\n\
1434                    โ†’ Or: git add -A (to stage all resolved files)\n\n\
1435                    Step 4: Complete the sync\n\
1436                    โ†’ Run: ca sync\n\
1437                    โ†’ Cascade will continue from where it left off\n\n\
1438                    Alternative: Abort and start over\n\
1439                    โ†’ Run: git cherry-pick --abort\n\
1440                    โ†’ Then: ca sync (starts fresh)",
1441                    conflicted_files.len(),
1442                    conflicted_files
1443                        .iter()
1444                        .map(|f| format!("  - {}", f))
1445                        .collect::<Vec<_>>()
1446                        .join("\n")
1447                )),
1448                summary: "Sync paused - conflicts need resolution".to_string(),
1449            };
1450
1451            return Ok(result);
1452        }
1453
1454        // Conflicts are resolved - continue the cherry-pick
1455        Output::info("Conflicts resolved, continuing cherry-pick...");
1456
1457        // Stage all resolved files
1458        self.git_repo.stage_conflict_resolved_files()?;
1459
1460        // Complete the cherry-pick by committing
1461        let cherry_pick_msg_file = git_dir.join("CHERRY_PICK_MSG");
1462        let commit_message = if cherry_pick_msg_file.exists() {
1463            std::fs::read_to_string(&cherry_pick_msg_file)
1464                .unwrap_or_else(|_| "Resolved conflicts".to_string())
1465        } else {
1466            "Resolved conflicts".to_string()
1467        };
1468
1469        match self.git_repo.commit(&commit_message) {
1470            Ok(_new_commit_id) => {
1471                Output::success("Cherry-pick completed");
1472
1473                // Clean up cherry-pick state
1474                if git_dir.join("CHERRY_PICK_HEAD").exists() {
1475                    let _ = std::fs::remove_file(git_dir.join("CHERRY_PICK_HEAD"));
1476                }
1477                if cherry_pick_msg_file.exists() {
1478                    let _ = std::fs::remove_file(&cherry_pick_msg_file);
1479                }
1480
1481                println!();
1482                Output::info("Continuing with rest of stack...");
1483                println!();
1484
1485                // Now continue with the rest of the rebase
1486                // We need to restart the full rebase since we don't track which entry we were on
1487                self.rebase_with_force_push(stack)
1488            }
1489            Err(e) => {
1490                let result = RebaseResult {
1491                    success: false,
1492                    branch_mapping: HashMap::new(),
1493                    conflicts: Vec::new(),
1494                    new_commits: Vec::new(),
1495                    error: Some(format!(
1496                        "Failed to complete cherry-pick: {}\n\n\
1497                        This usually means:\n\
1498                        - Git index is locked (another process accessing repo)\n\
1499                        - File permissions issue\n\
1500                        - Disk space issue\n\n\
1501                        Recovery:\n\
1502                        1. Check if another Git operation is running\n\
1503                        2. Run 'rm -f .git/index.lock' if stale lock exists\n\
1504                        3. Run 'git status' to check repo state\n\
1505                        4. Retry 'ca sync' after fixing the issue\n\n\
1506                        Or abort and start fresh:\n\
1507                        โ†’ Run: git cherry-pick --abort\n\
1508                        โ†’ Then: ca sync",
1509                        e
1510                    )),
1511                    summary: "Failed to complete cherry-pick".to_string(),
1512                };
1513
1514                Ok(result)
1515            }
1516        }
1517    }
1518}
1519
1520impl RebaseResult {
1521    /// Get a summary of the rebase operation
1522    pub fn get_summary(&self) -> String {
1523        if self.success {
1524            format!("โœ… {}", self.summary)
1525        } else {
1526            format!(
1527                "โŒ Rebase failed: {}",
1528                self.error.as_deref().unwrap_or("Unknown error")
1529            )
1530        }
1531    }
1532
1533    /// Check if any conflicts occurred
1534    pub fn has_conflicts(&self) -> bool {
1535        !self.conflicts.is_empty()
1536    }
1537
1538    /// Get the number of successful operations
1539    pub fn success_count(&self) -> usize {
1540        self.new_commits.len()
1541    }
1542}
1543
1544#[cfg(test)]
1545mod tests {
1546    use super::*;
1547    use std::path::PathBuf;
1548    use std::process::Command;
1549    use tempfile::TempDir;
1550
1551    #[allow(dead_code)]
1552    fn create_test_repo() -> (TempDir, PathBuf) {
1553        let temp_dir = TempDir::new().unwrap();
1554        let repo_path = temp_dir.path().to_path_buf();
1555
1556        // Initialize git repository
1557        Command::new("git")
1558            .args(["init"])
1559            .current_dir(&repo_path)
1560            .output()
1561            .unwrap();
1562        Command::new("git")
1563            .args(["config", "user.name", "Test"])
1564            .current_dir(&repo_path)
1565            .output()
1566            .unwrap();
1567        Command::new("git")
1568            .args(["config", "user.email", "test@test.com"])
1569            .current_dir(&repo_path)
1570            .output()
1571            .unwrap();
1572
1573        // Create initial commit
1574        std::fs::write(repo_path.join("README.md"), "# Test").unwrap();
1575        Command::new("git")
1576            .args(["add", "."])
1577            .current_dir(&repo_path)
1578            .output()
1579            .unwrap();
1580        Command::new("git")
1581            .args(["commit", "-m", "Initial"])
1582            .current_dir(&repo_path)
1583            .output()
1584            .unwrap();
1585
1586        (temp_dir, repo_path)
1587    }
1588
1589    #[test]
1590    fn test_conflict_region_creation() {
1591        let region = ConflictRegion {
1592            start: 0,
1593            end: 50,
1594            start_line: 1,
1595            end_line: 3,
1596            our_content: "function test() {\n    return true;\n}".to_string(),
1597            their_content: "function test() {\n  return true;\n}".to_string(),
1598        };
1599
1600        assert_eq!(region.start_line, 1);
1601        assert_eq!(region.end_line, 3);
1602        assert!(region.our_content.contains("return true"));
1603        assert!(region.their_content.contains("return true"));
1604    }
1605
1606    #[test]
1607    fn test_rebase_strategies() {
1608        assert_eq!(RebaseStrategy::ForcePush, RebaseStrategy::ForcePush);
1609        assert_eq!(RebaseStrategy::Interactive, RebaseStrategy::Interactive);
1610    }
1611
1612    #[test]
1613    fn test_rebase_options() {
1614        let options = RebaseOptions::default();
1615        assert_eq!(options.strategy, RebaseStrategy::ForcePush);
1616        assert!(!options.interactive);
1617        assert!(options.auto_resolve);
1618        assert_eq!(options.max_retries, 3);
1619    }
1620
1621    #[test]
1622    fn test_cleanup_guard_tracks_branches() {
1623        let mut guard = TempBranchCleanupGuard::new();
1624        assert!(guard.branches.is_empty());
1625
1626        guard.add_branch("test-branch-1".to_string());
1627        guard.add_branch("test-branch-2".to_string());
1628
1629        assert_eq!(guard.branches.len(), 2);
1630        assert_eq!(guard.branches[0], "test-branch-1");
1631        assert_eq!(guard.branches[1], "test-branch-2");
1632    }
1633
1634    #[test]
1635    fn test_cleanup_guard_prevents_double_cleanup() {
1636        use std::process::Command;
1637        use tempfile::TempDir;
1638
1639        // Create a temporary git repo
1640        let temp_dir = TempDir::new().unwrap();
1641        let repo_path = temp_dir.path();
1642
1643        Command::new("git")
1644            .args(["init"])
1645            .current_dir(repo_path)
1646            .output()
1647            .unwrap();
1648
1649        Command::new("git")
1650            .args(["config", "user.name", "Test"])
1651            .current_dir(repo_path)
1652            .output()
1653            .unwrap();
1654
1655        Command::new("git")
1656            .args(["config", "user.email", "test@test.com"])
1657            .current_dir(repo_path)
1658            .output()
1659            .unwrap();
1660
1661        // Create initial commit
1662        std::fs::write(repo_path.join("test.txt"), "test").unwrap();
1663        Command::new("git")
1664            .args(["add", "."])
1665            .current_dir(repo_path)
1666            .output()
1667            .unwrap();
1668        Command::new("git")
1669            .args(["commit", "-m", "initial"])
1670            .current_dir(repo_path)
1671            .output()
1672            .unwrap();
1673
1674        let git_repo = GitRepository::open(repo_path).unwrap();
1675
1676        // Create a test branch
1677        git_repo.create_branch("test-temp", None).unwrap();
1678
1679        let mut guard = TempBranchCleanupGuard::new();
1680        guard.add_branch("test-temp".to_string());
1681
1682        // First cleanup should work
1683        guard.cleanup(&git_repo);
1684        assert!(guard.cleaned);
1685
1686        // Second cleanup should be a no-op (shouldn't panic)
1687        guard.cleanup(&git_repo);
1688        assert!(guard.cleaned);
1689    }
1690
1691    #[test]
1692    fn test_rebase_result() {
1693        let result = RebaseResult {
1694            success: true,
1695            branch_mapping: std::collections::HashMap::new(),
1696            conflicts: vec!["abc123".to_string()],
1697            new_commits: vec!["def456".to_string()],
1698            error: None,
1699            summary: "Test summary".to_string(),
1700        };
1701
1702        assert!(result.success);
1703        assert!(result.has_conflicts());
1704        assert_eq!(result.success_count(), 1);
1705    }
1706}