#!/usr/bin/env bash
#
# monitor-common.sh - Shared utilities for humanize monitor functions
#
# This file contains common functions used by humanize monitor functions.
# It should be sourced by humanize.sh rather than executed directly.

# ========================================
# ANSI Color Constants
# ========================================

# These are defined as functions to allow dynamic evaluation
# (some terminals may not support all colors)
monitor_color_green() { echo "\033[1;32m"; }
monitor_color_yellow() { echo "\033[1;33m"; }
monitor_color_cyan() { echo "\033[1;36m"; }
monitor_color_magenta() { echo "\033[1;35m"; }
monitor_color_red() { echo "\033[1;31m"; }
monitor_color_reset() { echo "\033[0m"; }
monitor_color_bg() { echo "\033[44m"; }
monitor_color_bold() { echo "\033[1m"; }
monitor_color_dim() { echo "\033[2m"; }
monitor_color_blue() { echo "\033[1;34m"; }

# ========================================
# File Utilities
# ========================================

# Get file size (cross-platform: Linux uses -c%s, macOS uses -f%z)
# Usage: monitor_get_file_size "/path/to/file"
# Returns: file size in bytes, or 0 if file doesn't exist
monitor_get_file_size() {
    local file="$1"
    stat -c%s "$file" 2>/dev/null || stat -f%z "$file" 2>/dev/null || echo 0
}

# Find latest directory by timestamp name pattern (YYYY-MM-DD_HH-MM-SS)
# Usage: monitor_find_latest_session "/path/to/loop/dir"
# Returns: path to latest session directory, or empty string if none found
monitor_find_latest_session() {
    local loop_dir="$1"
    local latest_session=""

    if [[ ! -d "$loop_dir" ]]; then
        echo ""
        return
    fi

    # Use find instead of glob to avoid zsh "no matches found" errors
    while IFS= read -r session_dir; do
        [[ -z "$session_dir" ]] && continue
        [[ ! -d "$session_dir" ]] && continue

        local session_name=$(basename "$session_dir")
        if [[ "$session_name" =~ ^[0-9]{4}-[0-9]{2}-[0-9]{2}_[0-9]{2}-[0-9]{2}-[0-9]{2}$ ]]; then
            if [[ -z "$latest_session" ]] || [[ "$session_name" > "$(basename "$latest_session")" ]]; then
                latest_session="$session_dir"
            fi
        fi
    done < <(find "$loop_dir" -mindepth 1 -maxdepth 1 -type d 2>/dev/null)

    echo "$latest_session"
}

# ========================================
# Terminal Utilities
# ========================================

# Setup terminal for split view with fixed header
# Usage: monitor_setup_terminal <header_height>
monitor_setup_terminal() {
    local header_height="$1"

    # Clear screen
    clear

    # Set scroll region (leave top lines for status bar)
    printf "\033[${header_height};%dr" $(tput lines)

    # Move cursor to scroll region
    tput cup "$header_height" 0
}

# Restore terminal to normal state
# Usage: monitor_restore_terminal
monitor_restore_terminal() {
    # Reset scroll region to full screen
    printf "\033[r"

    # Move to bottom
    tput cup $(tput lines) 0
}

# ========================================
# Signal Handling
# ========================================

# Setup signal handlers for clean Ctrl+C handling
# This function should be called with the cleanup function name as argument
#
# Usage: monitor_setup_signal_handlers "cleanup_function_name"
#
# The cleanup function should:
# 1. Set a cleanup_done flag to prevent multiple calls
# 2. Set monitor_running=false to stop loops
# 3. Kill any background processes
# 4. Restore terminal state
#
# Example cleanup function:
#   _cleanup() {
#       [[ "$cleanup_done" == "true" ]] && return
#       cleanup_done=true
#       monitor_running=false
#       trap - INT TERM 2>/dev/null || true
#       [[ -n "$TAIL_PID" ]] && kill "$TAIL_PID" 2>/dev/null
#       monitor_restore_terminal
#       echo "Stopped."
#   }
#
# Note: This function is a documentation reference. The actual signal
# setup should be done inline in each monitor function for proper scope
# handling of local variables (cleanup_done, monitor_running, etc.)

# ========================================
# Status Color Helper
# ========================================

# Get color code for loop status
# Usage: color=$(monitor_get_status_color "active")
monitor_get_status_color() {
    local status="$1"
    case "$status" in
        active|methodology-analysis) echo "\033[1;32m" ;;  # green
        completed) echo "\033[1;36m" ;;  # cyan
        failed|error|timeout) echo "\033[1;31m" ;;  # red
        cancelled) echo "\033[1;33m" ;;  # yellow
        max-iterations) echo "\033[1;31m" ;;  # red
        unknown) echo "\033[2m" ;;  # dim
        *) echo "\033[1;33m" ;;  # yellow (default for unknown states)
    esac
}

# ========================================
# State File Detection
# ========================================

# Find state file in session directory
# Returns: state_file_path|loop_status
# - If state.md exists: returns "path/state.md|active"
# - If <STOP_REASON>-state.md exists: returns "path/<file>|<stop_reason>"
# - If no state file found: returns "|unknown"
#
# Usage: monitor_find_state_file "/path/to/session"
monitor_find_state_file() {
    local session_dir="$1"

    if [[ -z "$session_dir" || ! -d "$session_dir" ]]; then
        echo "|unknown"
        return
    fi

    # Priority 1: Active state files indicate running loop
    if [[ -f "$session_dir/methodology-analysis-state.md" ]]; then
        echo "$session_dir/methodology-analysis-state.md|methodology-analysis"
        return
    fi
    if [[ -f "$session_dir/state.md" ]]; then
        echo "$session_dir/state.md|active"
        return
    fi

    # Priority 2: Look for <STOP_REASON>-state.md files
    # Common stop reasons: completed, failed, cancelled, timeout, error, approve, maxiter
    local state_file=""
    local stop_reason=""
    while IFS= read -r f; do
        [[ -z "$f" ]] && continue
        if [[ -f "$f" ]]; then
            state_file="$f"
            # Extract stop reason from filename (e.g., "completed-state.md" -> "completed")
            local basename=$(basename "$f")
            stop_reason="${basename%-state.md}"
            break
        fi
    done < <(find "$session_dir" -maxdepth 1 -name '*-state.md' -type f 2>/dev/null)

    if [[ -n "$state_file" ]]; then
        echo "$state_file|$stop_reason"
    else
        echo "|unknown"
    fi
}

# ========================================
# YAML Frontmatter Parsing
# ========================================

# Extract a value from YAML frontmatter
# Usage: monitor_get_yaml_value "key" "/path/to/file.md"
# Returns: The value, or empty string if not found
monitor_get_yaml_value() {
    local key="$1"
    local file="$2"

    [[ ! -f "$file" ]] && return

    # Extract frontmatter (between first and second ---)
    local frontmatter
    frontmatter=$(sed -n '/^---$/,/^---$/{ /^---$/d; p; }' "$file" 2>/dev/null)

    # Extract value for key
    echo "$frontmatter" | grep -E "^${key}:" | sed "s/${key}: *//" | tr -d '"'
}

# ========================================
# Progress Display Helpers
# ========================================

# Format a timestamp for display
# Converts ISO format (2026-01-18T10:00:00Z) to readable format
# Usage: monitor_format_timestamp "2026-01-18T10:00:00Z"
monitor_format_timestamp() {
    local timestamp="$1"

    if [[ "$timestamp" == "N/A" || -z "$timestamp" ]]; then
        echo "N/A"
        return
    fi

    # Convert ISO format to more readable format
    echo "$timestamp" | sed 's/T/ /; s/Z/ UTC/'
}

# Truncate a string for display, adding ellipsis
# Usage: monitor_truncate_string "long string" <max_length> <direction>
# direction: "start" (keep end) or "end" (keep start, default)
monitor_truncate_string() {
    local str="$1"
    local max_len="$2"
    local direction="${3:-end}"

    if [[ ${#str} -le $max_len ]]; then
        echo "$str"
        return
    fi

    if [[ "$direction" == "start" ]]; then
        # Keep end, truncate start
        local suffix_len=$((max_len - 3))
        echo "...${str: -$suffix_len}"
    else
        # Keep start, truncate end
        local prefix_len=$((max_len - 3))
        echo "${str:0:$prefix_len}..."
    fi
}

# ========================================
# Goal Tracker Parsing
# ========================================

# Parse issue breakdown from goal-tracker.md
# Returns: blocking_issues|queued_issues|open_issues
# Usage: parse_goal_tracker_issue_counts "/path/to/goal-tracker.md"
parse_goal_tracker_issue_counts() {
    local tracker_file="$1"
    if [[ ! -f "$tracker_file" ]]; then
        echo "0|0|0"
        return
    fi

    _count_table_rows() {
        local start_pattern="$1"
        local end_pattern="$2"
        local row_count
        row_count=$(sed -n "/${start_pattern}/,/${end_pattern}/p" "$tracker_file" | grep -cE '^\|' || true)
        row_count=${row_count:-0}
        echo $((row_count > 2 ? row_count - 2 : 0))
    }

    local blocking_issues
    local queued_issues
    local open_issues

    blocking_issues=$(_count_table_rows '### Blocking Side Issues' '^###')
    queued_issues=$(_count_table_rows '### Queued Side Issues' '^###')
    open_issues=$((blocking_issues + queued_issues))

    if [[ "$open_issues" -eq 0 ]]; then
        open_issues=$(_count_table_rows '### Open Issues' '^###')
        blocking_issues="$open_issues"
    fi

    echo "${blocking_issues}|${queued_issues}|${open_issues}"
}

# Parse goal-tracker.md and return summary values
# Returns: total_acs|completed_acs|active_tasks|completed_tasks|deferred_tasks|open_issues|goal_summary
# Usage: parse_goal_tracker "/path/to/goal-tracker.md"
parse_goal_tracker() {
    local tracker_file="$1"
    if [[ ! -f "$tracker_file" ]]; then
        echo "0|0|0|0|0|0|No goal tracker"
        return
    fi

    # Helper: count data rows in a markdown table section (total rows minus header and separator)
    _count_table_rows() {
        local start_pattern="$1"
        local end_pattern="$2"
        local row_count
        row_count=$(sed -n "/${start_pattern}/,/${end_pattern}/p" "$tracker_file" | grep -cE '^\|' || true)
        row_count=${row_count:-0}
        echo $((row_count > 2 ? row_count - 2 : 0))
    }

    # Count Acceptance Criteria (supports both table and list formats)
    # Stop at next section header (##) to avoid counting ACs from other sections
    local total_acs
    total_acs=$(sed -n '/### Acceptance Criteria/,/^##/p' "$tracker_file" \
        | grep -cE '(^\|\s*\*{0,2}[A]?[C]-?[0-9]+|^-\s*\*{0,2}[A]?[C]-?[0-9]+)' || true)
    total_acs=${total_acs:-0}

    # Count Active Tasks
    local total_active_section_rows
    local completed_in_active
    local deferred_in_active

    total_active_section_rows=$(sed -n '/#### Active Tasks/,/^###/p' "$tracker_file" \
        | grep -cE '^\|' || true)
    total_active_section_rows=${total_active_section_rows:-0}
    local total_active_data_rows=$((total_active_section_rows > 2 ? total_active_section_rows - 2 : 0))

    completed_in_active=$(sed -n '/#### Active Tasks/,/^###/p' "$tracker_file" \
        | sed 's/\*\*//g' \
        | grep -ciE '^\|[^|]+\|[^|]+\|[[:space:]]*completed[[:space:]]*\|' || true)
    completed_in_active=${completed_in_active:-0}

    deferred_in_active=$(sed -n '/#### Active Tasks/,/^###/p' "$tracker_file" \
        | sed 's/\*\*//g' \
        | grep -ciE '^\|[^|]+\|[^|]+\|[[:space:]]*deferred[[:space:]]*\|' || true)
    deferred_in_active=${deferred_in_active:-0}

    local active_tasks=$((total_active_data_rows - completed_in_active - deferred_in_active))
    [[ "$active_tasks" -lt 0 ]] && active_tasks=0

    # Count Completed tasks
    local completed_tasks
    completed_tasks=$(_count_table_rows '### Completed and Verified' '^###')

    # Count verified ACs (unique AC entries in Completed section)
    local completed_acs
    completed_acs=$(sed -n '/### Completed and Verified/,/^###/p' "$tracker_file" \
        | grep -oE '^\|\s*[A]?[C]-?[0-9]+' | sort -u | wc -l | tr -d ' ')
    completed_acs=${completed_acs:-0}

    # Count Deferred tasks
    local deferred_tasks
    deferred_tasks=$(_count_table_rows '### Explicitly Deferred' '^###')

    # Count Open Issues (new schema prefers Blocking/Queued Side Issues; old schema used Open Issues)
    local issue_parts_raw
    local open_issues
    issue_parts_raw=$(parse_goal_tracker_issue_counts "$tracker_file")
    if [[ -n "${ZSH_VERSION:-}" ]]; then
        local -a issue_parts
        issue_parts=("${(@s:|:)issue_parts_raw}")
        open_issues="${issue_parts[3]}"
    else
        local -a issue_parts
        IFS='|' read -r -a issue_parts <<< "$issue_parts_raw"
        open_issues="${issue_parts[2]}"
    fi

    # Extract Ultimate Goal summary
    local goal_summary
    goal_summary=$(sed -n '/### Ultimate Goal/,/^###/p' "$tracker_file" \
        | grep -v '^###' | grep -v '^$' | grep -v '^\[To be' \
        | head -1 | sed 's/^[[:space:]]*//' | cut -c1-60)
    goal_summary="${goal_summary:-No goal defined}"

    echo "${total_acs}|${completed_acs}|${active_tasks}|${completed_tasks}|${deferred_tasks}|${open_issues}|${goal_summary}"
}