//! Phase guidance and deliverables tracking for contract management.
//!
//! This module provides structured guidance for each contract phase, tracking
//! expected deliverables and completion criteria.
//!
//! ## Contract Types
//!
//! ### Simple
//! - **Plan phase**: One required deliverable: "Plan"
//! - **Execute phase**: One required deliverable: "PR"
//!
//! ### Specification
//! - **Research phase**: One required deliverable: "Research Notes"
//! - **Specify phase**: One required deliverable: "Requirements Document"
//! - **Plan phase**: One required deliverable: "Plan"
//! - **Execute phase**: One required deliverable: "PR"
//! - **Review phase**: One required deliverable: "Release Notes"
//!
//! ### Execute
//! - **Execute phase only**: No deliverables at all

use serde::{Deserialize, Serialize};
use utoipa::ToSchema;
use uuid::Uuid;

/// Priority level for recommended deliverables
#[derive(Debug, Clone, Copy, PartialEq, Eq, Serialize, Deserialize, ToSchema)]
#[serde(rename_all = "lowercase")]
pub enum FilePriority {
    /// Must exist before advancing phase
    Required,
    /// Strongly suggested for phase completion
    Recommended,
    /// Nice to have, not blocking
    Optional,
}

/// A recommended file for a phase
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct RecommendedFile {
    /// Template ID to create from
    pub template_id: String,
    /// Suggested file name
    pub name_suggestion: String,
    /// Priority level
    pub priority: FilePriority,
    /// Brief description of purpose
    pub description: String,
}

/// Expected deliverables for a phase
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct PhaseDeliverables {
    /// Phase name
    pub phase: String,
    /// Recommended files to create
    pub recommended_files: Vec<RecommendedFile>,
    /// Whether a repository is required for this phase
    pub requires_repository: bool,
    /// Whether tasks should exist in this phase
    pub requires_tasks: bool,
    /// Guidance text for this phase
    pub guidance: String,
}

/// Status of a deliverable item
#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
pub struct DeliverableStatus {
    /// Template ID
    pub template_id: String,
    /// Expected name
    pub name: String,
    /// Priority
    pub priority: FilePriority,
    /// Whether it has been created
    pub completed: bool,
    /// File ID if created
    pub file_id: Option<Uuid>,
    /// Actual file name if created
    pub actual_name: Option<String>,
}

/// Checklist for phase completion
#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
pub struct PhaseChecklist {
    /// Current phase
    pub phase: String,
    /// File deliverables status
    pub file_deliverables: Vec<DeliverableStatus>,
    /// Whether repository is configured
    pub has_repository: bool,
    /// Whether repository was required
    pub repository_required: bool,
    /// Task statistics (for execute phase)
    pub task_stats: Option<TaskStats>,
    /// Overall completion percentage (0-100)
    pub completion_percentage: u8,
    /// Summary message
    pub summary: String,
    /// Suggestions for next actions
    pub suggestions: Vec<String>,
}

/// Task statistics for execute phase
#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
pub struct TaskStats {
    pub total: usize,
    pub pending: usize,
    pub running: usize,
    pub done: usize,
    pub failed: usize,
}

/// Minimal file info for checklist building
pub struct FileInfo {
    pub id: Uuid,
    pub name: String,
    pub contract_phase: Option<String>,
}

/// Minimal task info for checklist building
pub struct TaskInfo {
    pub id: Uuid,
    pub name: String,
    pub status: String,
}

/// Get phase deliverables configuration (legacy, defaults to "simple" contract type)
pub fn get_phase_deliverables(phase: &str) -> PhaseDeliverables {
    get_phase_deliverables_for_type(phase, "simple")
}

/// Get phase deliverables configuration for a specific contract type
///
/// ## Contract Types
///
/// ### Simple
/// - Plan: Only "Plan" deliverable (required)
/// - Execute: Only "PR" deliverable (required)
///
/// ### Specification
/// - Research: Only "Research Notes" deliverable (required)
/// - Specify: Only "Requirements Document" deliverable (required)
/// - Plan: Only "Plan" deliverable (required)
/// - Execute: Only "PR" deliverable (required)
/// - Review: Only "Release Notes" deliverable (required)
///
/// ### Execute
/// - Execute: No deliverables at all
pub fn get_phase_deliverables_for_type(phase: &str, contract_type: &str) -> PhaseDeliverables {
    match contract_type {
        "execute" => get_execute_type_deliverables(phase),
        "specification" => get_specification_type_deliverables(phase),
        "simple" | _ => get_simple_type_deliverables(phase),
    }
}

/// Get deliverables for 'simple' contract type
/// - Plan phase: Only "Plan" deliverable (required)
/// - Execute phase: Only "PR" deliverable (required)
fn get_simple_type_deliverables(phase: &str) -> PhaseDeliverables {
    match phase {
        "plan" => PhaseDeliverables {
            phase: "plan".to_string(),
            recommended_files: vec![
                RecommendedFile {
                    template_id: "plan".to_string(),
                    name_suggestion: "Plan".to_string(),
                    priority: FilePriority::Required,
                    description: "Implementation plan detailing the approach and tasks".to_string(),
                },
            ],
            requires_repository: true,
            requires_tasks: false,
            guidance: "Create a plan document that outlines the implementation approach. A repository must be configured before moving to Execute phase.".to_string(),
        },
        "execute" => PhaseDeliverables {
            phase: "execute".to_string(),
            recommended_files: vec![
                RecommendedFile {
                    template_id: "pr".to_string(),
                    name_suggestion: "PR".to_string(),
                    priority: FilePriority::Required,
                    description: "Pull request with the implemented changes".to_string(),
                },
            ],
            requires_repository: true,
            requires_tasks: true,
            guidance: "Execute the plan and create a PR with the implemented changes. Complete all tasks to finish the contract.".to_string(),
        },
        _ => PhaseDeliverables {
            phase: phase.to_string(),
            recommended_files: vec![],
            requires_repository: false,
            requires_tasks: false,
            guidance: "Unknown phase for simple contract type".to_string(),
        },
    }
}

/// Get deliverables for 'specification' contract type
/// - Research: Only "Research Notes" deliverable (required)
/// - Specify: Only "Requirements Document" deliverable (required)
/// - Plan: Only "Plan" deliverable (required)
/// - Execute: Only "PR" deliverable (required)
/// - Review: Only "Release Notes" deliverable (required)
fn get_specification_type_deliverables(phase: &str) -> PhaseDeliverables {
    match phase {
        "research" => PhaseDeliverables {
            phase: "research".to_string(),
            recommended_files: vec![
                RecommendedFile {
                    template_id: "research-notes".to_string(),
                    name_suggestion: "Research Notes".to_string(),
                    priority: FilePriority::Required,
                    description: "Document findings and insights during research".to_string(),
                },
            ],
            requires_repository: false,
            requires_tasks: false,
            guidance: "Focus on understanding the problem space and document your findings in the Research Notes before moving to Specify phase.".to_string(),
        },
        "specify" => PhaseDeliverables {
            phase: "specify".to_string(),
            recommended_files: vec![
                RecommendedFile {
                    template_id: "requirements".to_string(),
                    name_suggestion: "Requirements Document".to_string(),
                    priority: FilePriority::Required,
                    description: "Define functional and non-functional requirements".to_string(),
                },
            ],
            requires_repository: false,
            requires_tasks: false,
            guidance: "Define what needs to be built with clear requirements in the Requirements Document. Ensure specifications are detailed enough for planning.".to_string(),
        },
        "plan" => PhaseDeliverables {
            phase: "plan".to_string(),
            recommended_files: vec![
                RecommendedFile {
                    template_id: "plan".to_string(),
                    name_suggestion: "Plan".to_string(),
                    priority: FilePriority::Required,
                    description: "Implementation plan detailing the approach and tasks".to_string(),
                },
            ],
            requires_repository: true,
            requires_tasks: false,
            guidance: "Create a plan document that outlines the implementation approach. A repository must be configured before moving to Execute phase.".to_string(),
        },
        "execute" => PhaseDeliverables {
            phase: "execute".to_string(),
            recommended_files: vec![
                RecommendedFile {
                    template_id: "pr".to_string(),
                    name_suggestion: "PR".to_string(),
                    priority: FilePriority::Required,
                    description: "Pull request with the implemented changes".to_string(),
                },
            ],
            requires_repository: true,
            requires_tasks: true,
            guidance: "Execute the plan and create a PR with the implemented changes. Complete all tasks before moving to Review phase.".to_string(),
        },
        "review" => PhaseDeliverables {
            phase: "review".to_string(),
            recommended_files: vec![
                RecommendedFile {
                    template_id: "release-notes".to_string(),
                    name_suggestion: "Release Notes".to_string(),
                    priority: FilePriority::Required,
                    description: "Document changes for release communication".to_string(),
                },
            ],
            requires_repository: false,
            requires_tasks: false,
            guidance: "Review completed work and document the release in the Release Notes. The contract can be completed after review.".to_string(),
        },
        _ => PhaseDeliverables {
            phase: phase.to_string(),
            recommended_files: vec![],
            requires_repository: false,
            requires_tasks: false,
            guidance: "Unknown phase for specification contract type".to_string(),
        },
    }
}

/// Get deliverables for 'execute' contract type
/// - Execute phase only: No deliverables at all
fn get_execute_type_deliverables(phase: &str) -> PhaseDeliverables {
    match phase {
        "execute" => PhaseDeliverables {
            phase: "execute".to_string(),
            recommended_files: vec![], // No deliverables for execute-only contract type
            requires_repository: true,
            requires_tasks: true,
            guidance: "Execute the tasks directly. No deliverable documents are required for this contract type.".to_string(),
        },
        _ => PhaseDeliverables {
            phase: phase.to_string(),
            recommended_files: vec![],
            requires_repository: false,
            requires_tasks: false,
            guidance: "The 'execute' contract type only supports the 'execute' phase.".to_string(),
        },
    }
}

/// Build a phase checklist comparing expected vs actual deliverables (legacy, defaults to "simple")
pub fn get_phase_checklist(
    phase: &str,
    files: &[FileInfo],
    tasks: &[TaskInfo],
    has_repository: bool,
) -> PhaseChecklist {
    get_phase_checklist_for_type(phase, files, tasks, has_repository, "simple")
}

/// Build a phase checklist comparing expected vs actual deliverables for a specific contract type
pub fn get_phase_checklist_for_type(
    phase: &str,
    files: &[FileInfo],
    tasks: &[TaskInfo],
    has_repository: bool,
    contract_type: &str,
) -> PhaseChecklist {
    let deliverables = get_phase_deliverables_for_type(phase, contract_type);

    // Match files to expected deliverables
    let file_deliverables: Vec<DeliverableStatus> = deliverables
        .recommended_files
        .iter()
        .map(|rec| {
            // Check if a file with matching template ID or similar name exists
            let matched_file = files.iter().find(|f| {
                // Match by phase first
                f.contract_phase.as_deref() == Some(phase) &&
                // Then by name similarity (case-insensitive contains)
                (f.name.to_lowercase().contains(&rec.name_suggestion.to_lowercase()) ||
                 rec.name_suggestion.to_lowercase().contains(&f.name.to_lowercase()) ||
                 f.name.to_lowercase().contains(&rec.template_id.replace("-", " ")))
            });

            DeliverableStatus {
                template_id: rec.template_id.clone(),
                name: rec.name_suggestion.clone(),
                priority: rec.priority,
                completed: matched_file.is_some(),
                file_id: matched_file.map(|f| f.id),
                actual_name: matched_file.map(|f| f.name.clone()),
            }
        })
        .collect();

    // Calculate task stats for execute phase
    let task_stats = if phase == "execute" {
        let total = tasks.len();
        let pending = tasks.iter().filter(|t| t.status == "pending").count();
        let running = tasks.iter().filter(|t| t.status == "running").count();
        let done = tasks.iter().filter(|t| t.status == "done").count();
        let failed = tasks.iter().filter(|t| t.status == "failed" || t.status == "error").count();

        Some(TaskStats { total, pending, running, done, failed })
    } else {
        None
    };

    // Calculate completion percentage
    let mut completed_items = 0;
    let mut total_items = 0;

    // Count required and recommended files (not optional)
    for status in &file_deliverables {
        if status.priority != FilePriority::Optional {
            total_items += 1;
            if status.completed {
                completed_items += 1;
            }
        }
    }

    // Count repository if required
    if deliverables.requires_repository {
        total_items += 1;
        if has_repository {
            completed_items += 1;
        }
    }

    // Count tasks if in execute phase
    if let Some(ref stats) = task_stats {
        if stats.total > 0 {
            total_items += 1;
            if stats.done == stats.total && stats.total > 0 {
                completed_items += 1;
            }
        }
    }

    let completion_percentage = if total_items > 0 {
        ((completed_items as f64 / total_items as f64) * 100.0) as u8
    } else {
        100 // No requirements means complete
    };

    // Generate suggestions
    let mut suggestions = Vec::new();

    // Suggest missing required files
    for status in &file_deliverables {
        if !status.completed {
            match status.priority {
                FilePriority::Required => {
                    suggestions.push(format!("Create {} (required)", status.name));
                }
                FilePriority::Recommended => {
                    suggestions.push(format!("Consider creating {} (recommended)", status.name));
                }
                FilePriority::Optional => {
                    // Don't suggest optional items
                }
            }
        }
    }

    // Suggest repository if needed
    if deliverables.requires_repository && !has_repository {
        suggestions.push("Configure a repository for task execution".to_string());
    }

    // Suggest task actions for execute phase
    if let Some(ref stats) = task_stats {
        if stats.total == 0 {
            suggestions.push("Create tasks from the Task Breakdown document".to_string());
        } else if stats.pending > 0 {
            suggestions.push(format!("Run {} pending task(s)", stats.pending));
        } else if stats.running > 0 {
            suggestions.push(format!("Wait for {} running task(s) to complete", stats.running));
        } else if stats.failed > 0 {
            suggestions.push(format!("Address {} failed task(s)", stats.failed));
        } else if stats.done == stats.total && stats.total > 0 {
            // All tasks complete - for simple contracts, this is the terminal phase
            // For specification contracts, they should advance to review phase
            suggestions.push("Mark the contract as completed (for simple contracts) or advance to Review phase".to_string());
        }
    }

    // Suggest completion for review phase (terminal for specification contracts)
    if phase == "review" {
        let has_release_notes = file_deliverables.iter()
            .any(|d| d.template_id == "release-notes" && d.completed);
        if has_release_notes {
            suggestions.push("Mark the contract as completed".to_string());
        }
    }

    // Generate summary
    let summary = generate_phase_summary(phase, &file_deliverables, has_repository, &task_stats, completion_percentage);

    PhaseChecklist {
        phase: phase.to_string(),
        file_deliverables,
        has_repository,
        repository_required: deliverables.requires_repository,
        task_stats,
        completion_percentage,
        summary,
        suggestions,
    }
}

fn generate_phase_summary(
    phase: &str,
    deliverables: &[DeliverableStatus],
    has_repository: bool,
    task_stats: &Option<TaskStats>,
    completion_percentage: u8,
) -> String {
    let completed_count = deliverables.iter().filter(|d| d.completed).count();
    let total_count = deliverables.len();

    match phase {
        "research" => {
            if completed_count == 0 {
                "Research phase needs documentation. Create research notes or competitor analysis.".to_string()
            } else {
                format!("{}/{} research documents created. Consider transitioning to Specify phase.", completed_count, total_count)
            }
        }
        "specify" => {
            let has_required = deliverables.iter()
                .filter(|d| d.priority == FilePriority::Required)
                .all(|d| d.completed);

            if !has_required {
                "Specify phase requires a Requirements Document before transitioning.".to_string()
            } else if completion_percentage >= 66 {
                "Specifications are ready. Consider transitioning to Plan phase.".to_string()
            } else {
                format!("{}/{} specification documents created.", completed_count, total_count)
            }
        }
        "plan" => {
            let has_task_breakdown = deliverables.iter()
                .any(|d| d.template_id == "task-breakdown" && d.completed);

            if !has_task_breakdown {
                "Plan phase requires a Task Breakdown document.".to_string()
            } else if !has_repository {
                "Repository not configured. Configure a repository before Execute phase.".to_string()
            } else {
                "Planning complete. Ready to transition to Execute phase.".to_string()
            }
        }
        "execute" => {
            if let Some(stats) = task_stats {
                if stats.total == 0 {
                    "No tasks created. Create tasks from the Task Breakdown document.".to_string()
                } else if stats.done == stats.total {
                    "All tasks complete! Ready for Review phase.".to_string()
                } else {
                    format!("{}/{} tasks completed ({}% done)", stats.done, stats.total,
                        if stats.total > 0 { (stats.done * 100) / stats.total } else { 0 })
                }
            } else {
                "Execute phase in progress.".to_string()
            }
        }
        "review" => {
            let has_release_notes = deliverables.iter()
                .any(|d| d.template_id == "release-notes" && d.completed);

            if !has_release_notes {
                "Review phase requires Release Notes before completion.".to_string()
            } else {
                "Review documentation complete. Contract can be marked as done.".to_string()
            }
        }
        _ => format!("Phase {} - {}% complete", phase, completion_percentage),
    }
}

/// Check if phase targets are met for transition (legacy, defaults to "simple")
pub fn check_phase_completion(
    phase: &str,
    files: &[FileInfo],
    tasks: &[TaskInfo],
    has_repository: bool,
) -> bool {
    check_phase_completion_for_type(phase, files, tasks, has_repository, "simple")
}

/// Check if phase targets are met for transition for a specific contract type
pub fn check_phase_completion_for_type(
    phase: &str,
    files: &[FileInfo],
    tasks: &[TaskInfo],
    has_repository: bool,
    contract_type: &str,
) -> bool {
    let checklist = get_phase_checklist_for_type(phase, files, tasks, has_repository, contract_type);

    // Check required files are complete
    let required_files_complete = checklist.file_deliverables.iter()
        .filter(|d| d.priority == FilePriority::Required)
        .all(|d| d.completed);

    // Check repository if required
    let repository_ok = !checklist.repository_required || checklist.has_repository;

    // Check tasks if in execute phase
    let tasks_ok = if let Some(stats) = &checklist.task_stats {
        stats.total > 0 && stats.done == stats.total
    } else {
        true
    };

    required_files_complete && repository_ok && tasks_ok
}

/// Result of checking if deliverables are met for the current phase
#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
pub struct DeliverableCheckResult {
    /// Whether all required deliverables are met
    pub deliverables_met: bool,
    /// Whether the phase is ready to advance (includes all readiness checks)
    pub ready_to_advance: bool,
    /// Current phase
    pub phase: String,
    /// Next phase (if available)
    pub next_phase: Option<String>,
    /// List of required deliverables and their status
    pub required_deliverables: Vec<DeliverableItem>,
    /// List of what's missing (if any)
    pub missing: Vec<String>,
    /// Human-readable summary
    pub summary: String,
    /// Whether auto-progress is recommended
    pub auto_progress_recommended: bool,
}

/// A single deliverable item status
#[derive(Debug, Clone, Serialize, Deserialize, ToSchema)]
pub struct DeliverableItem {
    /// Name of the deliverable
    pub name: String,
    /// Type: "file", "repository", "pr", "tasks"
    pub deliverable_type: String,
    /// Whether it's met
    pub met: bool,
    /// Additional details
    pub details: Option<String>,
}

/// Check if all required deliverables for the current phase are met
/// This is used for both prompts and the check_deliverables_met tool
pub fn check_deliverables_met(
    phase: &str,
    contract_type: &str,
    files: &[FileInfo],
    tasks: &[TaskInfo],
    has_repository: bool,
    pr_url: Option<&str>,
) -> DeliverableCheckResult {
    let mut required_deliverables = Vec::new();
    let mut missing = Vec::new();

    // Get the deliverables for this contract type and phase
    let deliverables = get_phase_deliverables_for_type(phase, contract_type);

    // Check required files for this phase
    for rec in &deliverables.recommended_files {
        if rec.priority == FilePriority::Required {
            let matched = files.iter().any(|f| {
                f.contract_phase.as_deref() == Some(phase) &&
                (f.name.to_lowercase().contains(&rec.name_suggestion.to_lowercase()) ||
                 rec.name_suggestion.to_lowercase().contains(&f.name.to_lowercase()) ||
                 f.name.to_lowercase().contains(&rec.template_id.replace("-", " ")))
            });

            required_deliverables.push(DeliverableItem {
                name: rec.name_suggestion.clone(),
                deliverable_type: "file".to_string(),
                met: matched,
                details: if matched {
                    Some("Document exists".to_string())
                } else {
                    None
                },
            });

            if !matched {
                missing.push(format!("Create {} (required)", rec.name_suggestion));
            }
        }
    }

    // Check repository for phases that require it
    if deliverables.requires_repository {
        required_deliverables.push(DeliverableItem {
            name: "Repository".to_string(),
            deliverable_type: "repository".to_string(),
            met: has_repository,
            details: if has_repository {
                Some("Repository configured".to_string())
            } else {
                None
            },
        });

        if !has_repository {
            missing.push("Configure a repository".to_string());
        }
    }

    // Check tasks for execute phase
    if deliverables.requires_tasks {
        let total_tasks = tasks.len();
        let done_tasks = tasks.iter().filter(|t| t.status == "done").count();
        let tasks_complete = total_tasks > 0 && done_tasks == total_tasks;

        required_deliverables.push(DeliverableItem {
            name: "Tasks Completed".to_string(),
            deliverable_type: "tasks".to_string(),
            met: tasks_complete,
            details: Some(format!("{}/{} tasks done", done_tasks, total_tasks)),
        });

        if !tasks_complete {
            if total_tasks == 0 {
                missing.push("Create and complete tasks".to_string());
            } else {
                missing.push(format!("Complete remaining {} task(s)", total_tasks - done_tasks));
            }
        }
    }

    // For simple/specification contracts in execute phase, PR is a key deliverable
    if (contract_type == "simple" || contract_type == "specification") && phase == "execute" {
        let has_pr = pr_url.is_some() && !pr_url.unwrap_or("").is_empty();
        required_deliverables.push(DeliverableItem {
            name: "Pull Request".to_string(),
            deliverable_type: "pr".to_string(),
            met: has_pr,
            details: pr_url.map(|u| format!("PR: {}", u)),
        });

        if !has_pr {
            missing.push("Create a Pull Request for the completed work".to_string());
        }
    }

    let deliverables_met = required_deliverables.iter().all(|d| d.met);
    let next_phase = get_next_phase_for_contract(contract_type, phase);
    let ready_to_advance = deliverables_met && next_phase.is_some();

    let summary = if deliverables_met {
        if let Some(ref next) = next_phase {
            format!("All deliverables met for {} phase. Ready to advance to {} phase.", phase, next)
        } else {
            format!("All deliverables met for {} phase. This is the final phase.", phase)
        }
    } else {
        format!("{} deliverable(s) still needed for {} phase.", missing.len(), phase)
    };

    DeliverableCheckResult {
        deliverables_met,
        ready_to_advance,
        phase: phase.to_string(),
        next_phase,
        required_deliverables,
        missing,
        summary,
        auto_progress_recommended: deliverables_met && ready_to_advance,
    }
}

/// Get the next phase based on contract type
pub fn get_next_phase_for_contract(contract_type: &str, current_phase: &str) -> Option<String> {
    match contract_type {
        "simple" => match current_phase {
            "plan" => Some("execute".to_string()),
            "execute" => None, // Terminal phase for simple contracts
            _ => None,
        },
        "execute" => None, // Execute-only contracts don't have phase transitions
        "specification" | _ => match current_phase {
            "research" => Some("specify".to_string()),
            "specify" => Some("plan".to_string()),
            "plan" => Some("execute".to_string()),
            "execute" => Some("review".to_string()),
            "review" => None, // Final phase
            _ => None,
        },
    }
}

/// Determine if the contract should auto-progress to the next phase
/// This is called when deliverables are met and autonomous_loop is enabled
pub fn should_auto_progress(
    phase: &str,
    contract_type: &str,
    files: &[FileInfo],
    tasks: &[TaskInfo],
    has_repository: bool,
    pr_url: Option<&str>,
    autonomous_loop: bool,
) -> AutoProgressDecision {
    let check = check_deliverables_met(phase, contract_type, files, tasks, has_repository, pr_url);

    if !check.deliverables_met {
        return AutoProgressDecision {
            should_progress: false,
            next_phase: None,
            reason: format!("Deliverables not met: {}", check.missing.join(", ")),
            action: AutoProgressAction::WaitForDeliverables,
        };
    }

    if check.next_phase.is_none() {
        return AutoProgressDecision {
            should_progress: false,
            next_phase: None,
            reason: "This is the terminal phase. Contract can be completed.".to_string(),
            action: AutoProgressAction::CompleteContract,
        };
    }

    if autonomous_loop {
        AutoProgressDecision {
            should_progress: true,
            next_phase: check.next_phase,
            reason: "All deliverables met and autonomous_loop is enabled.".to_string(),
            action: AutoProgressAction::AdvancePhase,
        }
    } else {
        AutoProgressDecision {
            should_progress: false,
            next_phase: check.next_phase,
            reason: "All deliverables met. Suggest advancing to next phase.".to_string(),
            action: AutoProgressAction::SuggestAdvance,
        }
    }
}

/// Result of auto-progress decision
#[derive(Debug, Clone, Serialize, Deserialize)]
pub struct AutoProgressDecision {
    /// Whether to automatically progress
    pub should_progress: bool,
    /// The next phase to progress to
    pub next_phase: Option<String>,
    /// Reason for the decision
    pub reason: String,
    /// Recommended action
    pub action: AutoProgressAction,
}

/// Actions that can be taken based on auto-progress decision
#[derive(Debug, Clone, Serialize, Deserialize)]
pub enum AutoProgressAction {
    /// Wait for required deliverables
    WaitForDeliverables,
    /// Automatically advance to next phase
    AdvancePhase,
    /// Suggest user to advance (when not autonomous)
    SuggestAdvance,
    /// Contract is complete, mark as done
    CompleteContract,
}

/// Generate enhanced prompt guidance for deliverable checking
pub fn generate_deliverable_prompt_guidance(
    phase: &str,
    contract_type: &str,
    check_result: &DeliverableCheckResult,
) -> String {
    let mut guidance = String::new();

    guidance.push_str("\n## Phase Deliverables Status\n\n");
    guidance.push_str(&format!("**Current Phase**: {} | **Contract Type**: {}\n\n",
        capitalize(phase), contract_type));

    // Show required deliverables checklist
    guidance.push_str("### Required Deliverables Checklist\n");
    for item in &check_result.required_deliverables {
        let status = if item.met { "[x]" } else { "[ ]" };
        let details = item.details.as_ref().map(|d| format!(" - {}", d)).unwrap_or_default();
        guidance.push_str(&format!("{} **{}** ({}){}\n", status, item.name, item.deliverable_type, details));
    }

    // Show status and next actions
    guidance.push_str("\n### Status\n");
    if check_result.deliverables_met {
        guidance.push_str("**All deliverables are met.**\n\n");
        if let Some(ref next) = check_result.next_phase {
            guidance.push_str(&format!("Ready to advance to **{}** phase.\n", next));
            if check_result.auto_progress_recommended {
                guidance.push_str(&format!("\n**ACTION REQUIRED**: Since all deliverables are met, you should call `advance_phase` with `new_phase=\"{}\"` to progress the contract.\n", next));
            }
        } else {
            guidance.push_str("This is the terminal phase. The contract can be marked as completed.\n");
        }
    } else {
        guidance.push_str("**Deliverables not yet met.**\n\n");
        guidance.push_str("Missing:\n");
        for item in &check_result.missing {
            guidance.push_str(&format!("- {}\n", item));
        }
        guidance.push_str("\nComplete the missing deliverables before advancing to the next phase.\n");
    }

    guidance
}

/// Format checklist as markdown for LLM context
pub fn format_checklist_markdown(checklist: &PhaseChecklist) -> String {
    let mut md = format!("## Phase Progress ({} Phase)\n\n", capitalize(&checklist.phase));

    // File deliverables
    md.push_str("### Deliverables\n");
    for status in &checklist.file_deliverables {
        let check = if status.completed { "+" } else { "-" };
        let priority_label = match status.priority {
            FilePriority::Required => " (required)",
            FilePriority::Recommended => " (recommended)",
            FilePriority::Optional => " (optional)",
        };

        if status.completed {
            md.push_str(&format!("[{}] {} - \"{}\"\n", check, status.name, status.actual_name.as_deref().unwrap_or("created")));
        } else {
            md.push_str(&format!("[{}] {}{}\n", check, status.name, priority_label));
        }
    }

    // Repository status
    if checklist.repository_required {
        let check = if checklist.has_repository { "+" } else { "-" };
        md.push_str(&format!("[{}] Repository configured (required)\n", check));
    }

    // Task stats for execute phase
    if let Some(ref stats) = checklist.task_stats {
        md.push_str(&format!("\n### Task Progress\n"));
        md.push_str(&format!("- Total: {}\n", stats.total));
        md.push_str(&format!("- Done: {}\n", stats.done));
        if stats.pending > 0 {
            md.push_str(&format!("- Pending: {}\n", stats.pending));
        }
        if stats.running > 0 {
            md.push_str(&format!("- Running: {}\n", stats.running));
        }
        if stats.failed > 0 {
            md.push_str(&format!("- Failed: {}\n", stats.failed));
        }
    }

    // Summary
    md.push_str(&format!("\n**Status**: {} ({}% complete)\n", checklist.summary, checklist.completion_percentage));

    // Suggestions
    if !checklist.suggestions.is_empty() {
        md.push_str("\n**Next Steps**:\n");
        for suggestion in &checklist.suggestions {
            md.push_str(&format!("- {}\n", suggestion));
        }
    }

    md
}

fn capitalize(s: &str) -> String {
    let mut chars = s.chars();
    match chars.next() {
        None => String::new(),
        Some(first) => first.to_uppercase().collect::<String>() + chars.as_str(),
    }
}

#[cfg(test)]
mod tests {
    use super::*;

    #[test]
    fn test_get_phase_deliverables_simple() {
        // Simple contract type: Plan phase has only "Plan" deliverable
        let plan = get_phase_deliverables_for_type("plan", "simple");
        assert_eq!(plan.phase, "plan");
        assert!(plan.requires_repository);
        assert_eq!(plan.recommended_files.len(), 1);
        assert_eq!(plan.recommended_files[0].template_id, "plan");
        assert_eq!(plan.recommended_files[0].priority, FilePriority::Required);

        // Simple contract type: Execute phase has only "PR" deliverable
        let execute = get_phase_deliverables_for_type("execute", "simple");
        assert_eq!(execute.phase, "execute");
        assert!(execute.requires_repository);
        assert!(execute.requires_tasks);
        assert_eq!(execute.recommended_files.len(), 1);
        assert_eq!(execute.recommended_files[0].template_id, "pr");
        assert_eq!(execute.recommended_files[0].priority, FilePriority::Required);
    }

    #[test]
    fn test_get_phase_deliverables_specification() {
        // Specification: Research phase has only "Research Notes" deliverable
        let research = get_phase_deliverables_for_type("research", "specification");
        assert_eq!(research.phase, "research");
        assert!(!research.requires_repository);
        assert_eq!(research.recommended_files.len(), 1);
        assert_eq!(research.recommended_files[0].template_id, "research-notes");
        assert_eq!(research.recommended_files[0].priority, FilePriority::Required);

        // Specification: Specify phase has only "Requirements Document" deliverable
        let specify = get_phase_deliverables_for_type("specify", "specification");
        assert_eq!(specify.phase, "specify");
        assert_eq!(specify.recommended_files.len(), 1);
        assert_eq!(specify.recommended_files[0].template_id, "requirements");
        assert_eq!(specify.recommended_files[0].priority, FilePriority::Required);

        // Specification: Plan phase has only "Plan" deliverable
        let plan = get_phase_deliverables_for_type("plan", "specification");
        assert_eq!(plan.phase, "plan");
        assert_eq!(plan.recommended_files.len(), 1);
        assert_eq!(plan.recommended_files[0].template_id, "plan");

        // Specification: Execute phase has only "PR" deliverable
        let execute = get_phase_deliverables_for_type("execute", "specification");
        assert_eq!(execute.phase, "execute");
        assert_eq!(execute.recommended_files.len(), 1);
        assert_eq!(execute.recommended_files[0].template_id, "pr");

        // Specification: Review phase has only "Release Notes" deliverable
        let review = get_phase_deliverables_for_type("review", "specification");
        assert_eq!(review.phase, "review");
        assert_eq!(review.recommended_files.len(), 1);
        assert_eq!(review.recommended_files[0].template_id, "release-notes");
        assert_eq!(review.recommended_files[0].priority, FilePriority::Required);
    }

    #[test]
    fn test_get_phase_deliverables_execute_type() {
        // Execute contract type: Only execute phase, NO deliverables
        let execute = get_phase_deliverables_for_type("execute", "execute");
        assert_eq!(execute.phase, "execute");
        assert!(execute.requires_repository);
        assert!(execute.requires_tasks);
        assert!(execute.recommended_files.is_empty()); // NO deliverables

        // Execute contract type: Other phases should return empty deliverables
        let plan = get_phase_deliverables_for_type("plan", "execute");
        assert!(plan.recommended_files.is_empty());
    }

    #[test]
    fn test_phase_checklist_empty_simple() {
        let checklist = get_phase_checklist_for_type("plan", &[], &[], false, "simple");
        assert_eq!(checklist.completion_percentage, 0);
        assert!(!checklist.suggestions.is_empty());
    }

    #[test]
    fn test_phase_checklist_execute_type_no_deliverables() {
        // Execute contract type with no file deliverables
        let checklist = get_phase_checklist_for_type("execute", &[], &[], true, "execute");
        // Should have no file deliverables
        assert!(checklist.file_deliverables.is_empty());
    }

    #[test]
    fn test_check_phase_completion_specification() {
        let files = vec![
            FileInfo {
                id: Uuid::new_v4(),
                name: "Requirements Document".to_string(),
                contract_phase: Some("specify".to_string()),
            },
        ];

        // Specify phase has required file for specification contract type
        let complete = check_phase_completion_for_type("specify", &files, &[], false, "specification");
        assert!(complete);
    }

    #[test]
    fn test_check_phase_completion_simple() {
        let files = vec![
            FileInfo {
                id: Uuid::new_v4(),
                name: "Plan".to_string(),
                contract_phase: Some("plan".to_string()),
            },
        ];

        // Plan phase has required "Plan" file for simple contract type
        let complete = check_phase_completion_for_type("plan", &files, &[], true, "simple");
        assert!(complete);
    }

    #[test]
    fn test_legacy_functions_default_to_simple() {
        // Legacy get_phase_deliverables defaults to simple
        let plan = get_phase_deliverables("plan");
        assert_eq!(plan.recommended_files.len(), 1);
        assert_eq!(plan.recommended_files[0].template_id, "plan");
    }
}