#!/bin/bash

# ============================================================================
# Claude Code Statusline - API-Synced LIVE Cost Module
# ============================================================================
#
# Calculates LIVE cost by reading JSONL files within the Anthropic API's
# 5-hour billing window. This ensures LIVE syncs with the reset timer.
#
# Data Sources:
# - Anthropic OAuth API: Gets 5-hour window boundaries (resets_at)
# - Local JSONL files: Reads token usage from ~/.claude/projects/
#
# Pricing (per million tokens):
# - Opus 4.5: Input $5, Output $25, Cache Write $6.25, Cache Read $0.50
# - Sonnet 4.5: Input $3, Output $15, Cache Write $3.75, Cache Read $0.30
# - Haiku 4.5: Input $1, Output $5, Cache Write $1.25, Cache Read $0.10
#
# Dependencies: usage_limits.sh (for OAuth token), jq
# ============================================================================

# Prevent multiple includes
[[ "${STATUSLINE_COST_API_LIVE_LOADED:-}" == "true" ]] && return 0
export STATUSLINE_COST_API_LIVE_LOADED=true

# Load pricing module (single source of truth for model rates)
source "${BASH_SOURCE[0]%/*}/pricing.sh"

# ============================================================================
# UTILITY FUNCTIONS
# ============================================================================

# Format tokens in compact notation (e.g., 1.5M, 500K)
# Used by block_projection, token_usage, and session components
format_tokens_compact() {
    local tokens="${1:-0}"

    # Handle empty or non-numeric input
    if [[ -z "$tokens" || ! "$tokens" =~ ^[0-9]+$ ]]; then
        echo "0"
        return
    fi

    if [[ "$tokens" -ge 1000000 ]]; then
        awk -v t="$tokens" 'BEGIN { printf "%.1fM", t / 1000000 }'
    elif [[ "$tokens" -ge 1000 ]]; then
        awk -v t="$tokens" 'BEGIN { printf "%.1fK", t / 1000 }'
    else
        echo "$tokens"
    fi
}

# Cache TTL for API-synced LIVE (30 seconds)
API_LIVE_CACHE_TTL="${API_LIVE_CACHE_TTL:-30}"

# ============================================================================
# JSONL DIRECTORY DISCOVERY
# ============================================================================

# Get Claude projects directory path
get_claude_projects_dir() {
    local projects_dir=""

    # Check environment variable first
    if [[ -n "${CLAUDE_CONFIG_DIR:-}" ]]; then
        projects_dir="${CLAUDE_CONFIG_DIR}/projects"
    elif [[ -d "$HOME/.claude/projects" ]]; then
        projects_dir="$HOME/.claude/projects"
    elif [[ -d "$HOME/.config/claude/projects" ]]; then
        projects_dir="$HOME/.config/claude/projects"
    fi

    echo "$projects_dir"
}

# ============================================================================
# COST CALCULATION
# ============================================================================

# Calculate cost for a single entry based on token usage
# Args: model, input_tokens, output_tokens, cache_write_5m_tokens, cache_write_1h_tokens, cache_read_tokens
# Legacy 5-arg form (model, input, output, cache_write, cache_read) is supported —
# when only cache_write_tokens is provided, it's billed as 5m writes.
calculate_entry_cost() {
    local model="$1"
    local input_tokens="${2:-0}"
    local output_tokens="${3:-0}"
    local cw_5m_tokens="${4:-0}"
    local cw_1h_tokens cache_read_tokens

    # Support legacy 5-arg signature: (model, input, output, cache_write, cache_read)
    if [[ $# -le 5 ]]; then
        cw_1h_tokens=0
        cache_read_tokens="${5:-0}"
    else
        cw_1h_tokens="${5:-0}"
        cache_read_tokens="${6:-0}"
    fi

    # Get pricing for model (5-col: input output cw_5m cw_1h cache_read)
    local pricing
    pricing=$(get_model_pricing "$model")

    # Parse pricing values
    local input_price output_price cw_5m_price cw_1h_price cache_read_price
    read -r input_price output_price cw_5m_price cw_1h_price cache_read_price <<< "$pricing"

    # Calculate cost (prices are per million tokens)
    local cost
    cost=$(awk -v it="$input_tokens" -v ip="$input_price" \
               -v ot="$output_tokens" -v op="$output_price" \
               -v cw5="$cw_5m_tokens" -v cw5p="$cw_5m_price" \
               -v cw1="$cw_1h_tokens" -v cw1p="$cw_1h_price" \
               -v crt="$cache_read_tokens" -v crp="$cache_read_price" \
        'BEGIN {
            total = (it * ip + ot * op + cw5 * cw5p + cw1 * cw1p + crt * crp) / 1000000
            printf "%.6f", total
        }' 2>/dev/null)

    echo "${cost:-0}"
}

# ============================================================================
# API-SYNCED LIVE CALCULATION
# ============================================================================

# Get the 5-hour window start time from API's resets_at
# Returns: Unix epoch timestamp of window start
get_api_window_start() {
    # Get resets_at from usage_limits component (already fetched and cached)
    local resets_at="${COMPONENT_USAGE_FIVE_HOUR_RESET:-}"

    if [[ -z "$resets_at" || "$resets_at" == "null" ]]; then
        # Fallback 1: Native JSON from Claude Code stdin (zero-latency)
        if [[ -n "${STATUSLINE_INPUT_JSON:-}" ]]; then
            resets_at=$(echo "$STATUSLINE_INPUT_JSON" | jq -r '.rate_limits.five_hour.resets_at // .five_hour.resets_at // empty' 2>/dev/null)
            if [[ -n "$resets_at" && "$resets_at" != "null" ]]; then
                debug_log "Using native JSON fallback for resets_at: $resets_at" "INFO"
            fi
        fi
    fi

    if [[ -z "$resets_at" || "$resets_at" == "null" ]]; then
        # Fallback 2: OAuth API (slower, requires token)
        local usage_data
        usage_data=$(fetch_usage_limits 2>/dev/null)
        resets_at=$(echo "$usage_data" | jq -r '.five_hour.resets_at // empty' 2>/dev/null)
    fi

    if [[ -z "$resets_at" || "$resets_at" == "null" ]]; then
        debug_log "No resets_at available (no component data, no native JSON, no OAuth)" "WARN"
        echo ""
        return 1
    fi

    # Parse resets_at to epoch
    local reset_epoch

    # Detect epoch timestamp (pure digits = Unix epoch seconds from CC v2.1.80+)
    if [[ "$resets_at" =~ ^[0-9]+$ ]]; then
        reset_epoch="$resets_at"
    else
        local normalized_ts
        normalized_ts=$(echo "$resets_at" | sed 's/\.[0-9]*//')

        if [[ "$(uname -s)" == "Darwin" ]]; then
            local mac_ts
            mac_ts=$(echo "$normalized_ts" | sed 's/+00:00/+0000/; s/Z$/+0000/; s/+\([0-9][0-9]\):\([0-9][0-9]\)/+\1\2/')
            reset_epoch=$(date -j -f "%Y-%m-%dT%H:%M:%S%z" "$mac_ts" "+%s" 2>/dev/null)
        else
            reset_epoch=$(date -d "$resets_at" "+%s" 2>/dev/null)
        fi
    fi

    if [[ -z "$reset_epoch" ]]; then
        debug_log "Could not parse API resets_at: $resets_at" "WARN"
        echo ""
        return 1
    fi

    # Calculate window start (5 hours before reset)
    local window_start=$((reset_epoch - 5 * 3600))
    echo "$window_start"
}

# Calculate LIVE cost from JSONL files within API's 5-hour window
# OPTIMIZED: Single jq+awk pipeline (no per-entry jq calls)
# Returns: Total cost in USD (e.g., "18.51")
calculate_api_synced_live() {
    local projects_dir
    projects_dir=$(get_claude_projects_dir)

    if [[ -z "$projects_dir" || ! -d "$projects_dir" ]]; then
        debug_log "Claude projects directory not found" "WARN"
        echo "0.00"
        return 1
    fi

    local window_start_epoch
    window_start_epoch=$(get_api_window_start)

    if [[ -z "$window_start_epoch" ]]; then
        debug_log "Could not determine API window start" "WARN"
        echo "0.00"
        return 1
    fi

    # Convert epoch to ISO format for string comparison
    local window_start_iso
    if [[ "$(uname -s)" == "Darwin" ]]; then
        window_start_iso=$(date -u -r "$window_start_epoch" "+%Y-%m-%dT%H:%M:%S" 2>/dev/null)
    else
        window_start_iso=$(date -u -d "@$window_start_epoch" "+%Y-%m-%dT%H:%M:%S" 2>/dev/null)
    fi

    debug_log "API LIVE window start: $window_start_iso" "INFO"

    # Get pricing block from single source of truth
    local awk_pricing
    awk_pricing=$(get_awk_pricing_block)

    # OPTIMIZED: Single jq+awk pipeline
    local total_cost
    total_cost=$(find "$projects_dir" -name "*.jsonl" -type f -mmin -360 2>/dev/null | while read -r jsonl_file; do
        [[ -z "$jsonl_file" ]] && continue
        jq -r 'select(.type == "assistant") | select(.message.usage) | select(.timestamp) |
            [.timestamp, (.message.model // "default"),
             (.message.usage.input_tokens // 0),
             (.message.usage.output_tokens // 0),
             (.message.usage.cache_creation.ephemeral_5m_input_tokens // 0),
             (.message.usage.cache_creation.ephemeral_1h_input_tokens // 0),
             (.message.usage.cache_creation_input_tokens // 0),
             (.message.usage.cache_read_input_tokens // 0)] | @tsv' "$jsonl_file" 2>/dev/null
    done | awk -F'\t' -v start="$window_start_iso" "
    BEGIN {
        total = 0
        # Pricing from pricing.sh (single source of truth)
$awk_pricing
    }
    {
        ts = \$1
        gsub(/\.[0-9]+Z?\$/, \"\", ts)
        if (ts < start) next

        model = \$2
        input = \$3 + 0
        output = \$4 + 0
        cw_5m = \$5 + 0
        cw_1h = \$6 + 0
        cw_flat = \$7 + 0
        cache_read = \$8 + 0

        # Fallback: older entries lack nested cache_creation split.
        if (cw_5m + cw_1h == 0 && cw_flat > 0) cw_5m = cw_flat

        pricing = p[model]
        if (pricing == \"\") pricing = p[\"default\"]
        split(pricing, pr, \" \")
        cost = (input * pr[1] + output * pr[2] + cw_5m * pr[3] + cw_1h * pr[4] + cache_read * pr[5]) / 1000000
        total += cost
    }
    END {
        printf \"%.2f\", total
    }")

    debug_log "API LIVE calculated: \$${total_cost}" "INFO"
    echo "${total_cost:-0.00}"
}

# Get API-synced LIVE cost with caching
get_api_synced_live_cost() {
    # Check cache first
    local cache_key="api_synced_live"
    local cached_result
    cached_result=$(get_cached_value "$cache_key" "$API_LIVE_CACHE_TTL" 2>/dev/null)

    if [[ -n "$cached_result" ]]; then
        debug_log "Using cached API-synced LIVE: \$${cached_result}" "INFO"
        echo "$cached_result"
        return 0
    fi

    # Calculate fresh
    local live_cost
    live_cost=$(calculate_api_synced_live)

    # Cache result
    set_cached_value "$cache_key" "$live_cost" 2>/dev/null

    echo "$live_cost"
}

# ============================================================================
# NATIVE BLOCK METRICS
# ============================================================================

# Calculate token counts in current 5-hour window
# Returns: total_tokens:input_tokens:output_tokens:cache_read:cache_write
calculate_window_tokens() {
    local projects_dir
    projects_dir=$(get_claude_projects_dir)

    if [[ -z "$projects_dir" || ! -d "$projects_dir" ]]; then
        echo "0:0:0:0:0"
        return 1
    fi

    local window_start_epoch
    window_start_epoch=$(get_api_window_start)

    if [[ -z "$window_start_epoch" ]]; then
        echo "0:0:0:0:0"
        return 1
    fi

    # Convert epoch to ISO format for string comparison
    local window_start_iso
    if [[ "$(uname -s)" == "Darwin" ]]; then
        window_start_iso=$(date -u -r "$window_start_epoch" "+%Y-%m-%dT%H:%M:%S" 2>/dev/null)
    else
        window_start_iso=$(date -u -d "@$window_start_epoch" "+%Y-%m-%dT%H:%M:%S" 2>/dev/null)
    fi

    # Single jq+awk pass to sum all token types
    local result
    result=$(find "$projects_dir" -name "*.jsonl" -type f -mmin -360 2>/dev/null | while read -r jsonl_file; do
        [[ -z "$jsonl_file" ]] && continue
        jq -r 'select(.type == "assistant") | select(.message.usage) | select(.timestamp) |
            [.timestamp,
             (.message.usage.input_tokens // 0),
             (.message.usage.output_tokens // 0),
             (.message.usage.cache_read_input_tokens // 0),
             (.message.usage.cache_creation_input_tokens // 0)] | @tsv' "$jsonl_file" 2>/dev/null
    done | awk -F'\t' -v start="$window_start_iso" '
    BEGIN {
        total_input = 0; total_output = 0; cache_read = 0; cache_write = 0
    }
    {
        ts = $1
        gsub(/\.[0-9]+Z?$/, "", ts)
        if (ts < start) next

        total_input += $2 + 0
        total_output += $3 + 0
        cache_read += $4 + 0
        cache_write += $5 + 0
    }
    END {
        total = total_input + total_output
        printf "%d:%d:%d:%d:%d", total, total_input, total_output, cache_read, cache_write
    }')

    debug_log "Window tokens calculated: $result" "INFO"
    echo "${result:-0:0:0:0:0}"
}

# Get cached window tokens (30s TTL)
get_cached_window_tokens() {
    local cache_key="window_tokens"
    local cached_result
    cached_result=$(get_cached_value "$cache_key" "$API_LIVE_CACHE_TTL" 2>/dev/null)

    if [[ -n "$cached_result" ]]; then
        echo "$cached_result"
        return 0
    fi

    local result
    result=$(calculate_window_tokens)
    set_cached_value "$cache_key" "$result" 2>/dev/null
    echo "$result"
}

# Calculate native burn rate from JSONL activity in 5-hour window
# Returns: tokens_per_minute:cost_per_hour
calculate_native_burn_rate() {
    local window_start_epoch
    window_start_epoch=$(get_api_window_start)

    if [[ -z "$window_start_epoch" ]]; then
        echo "0:0.00"
        return 1
    fi

    local now_epoch
    now_epoch=$(date +%s)

    # Calculate elapsed minutes since window start
    local elapsed_seconds=$((now_epoch - window_start_epoch))
    local elapsed_minutes=$((elapsed_seconds / 60))

    # Avoid division by zero
    if [[ "$elapsed_minutes" -lt 1 ]]; then
        elapsed_minutes=1
    fi

    # Get token counts from window
    local token_data
    token_data=$(get_cached_window_tokens)
    local total_tokens
    total_tokens=$(echo "$token_data" | cut -d: -f1)
    total_tokens="${total_tokens:-0}"

    # Calculate tokens per minute
    local tokens_per_minute
    tokens_per_minute=$((total_tokens / elapsed_minutes))

    # Get cost in window and calculate cost per hour
    local live_cost
    live_cost=$(get_api_synced_live_cost)
    live_cost="${live_cost:-0.00}"

    local cost_per_hour
    cost_per_hour=$(awk -v cost="$live_cost" -v mins="$elapsed_minutes" \
        'BEGIN { printf "%.2f", (cost / mins) * 60 }' 2>/dev/null)

    debug_log "Native burn rate: ${tokens_per_minute}/min, \$${cost_per_hour}/hr" "INFO"
    echo "${tokens_per_minute}:${cost_per_hour}"
}

# Get cached burn rate (30s TTL)
get_cached_native_burn_rate() {
    local cache_key="native_burn_rate"
    local cached_result
    cached_result=$(get_cached_value "$cache_key" "$API_LIVE_CACHE_TTL" 2>/dev/null)

    if [[ -n "$cached_result" ]]; then
        echo "$cached_result"
        return 0
    fi

    local result
    result=$(calculate_native_burn_rate)
    set_cached_value "$cache_key" "$result" 2>/dev/null
    echo "$result"
}

# Get native reset timer info from OAuth API
# Returns: reset_time_local:remaining_minutes
get_native_reset_info() {
    # Get resets_at from usage_limits component
    local resets_at="${COMPONENT_USAGE_FIVE_HOUR_RESET:-}"

    if [[ -z "$resets_at" || "$resets_at" == "null" ]]; then
        # Fallback 1: Native JSON from Claude Code stdin (zero-latency)
        if [[ -n "${STATUSLINE_INPUT_JSON:-}" ]]; then
            resets_at=$(echo "$STATUSLINE_INPUT_JSON" | jq -r '.rate_limits.five_hour.resets_at // .five_hour.resets_at // empty' 2>/dev/null)
            if [[ -n "$resets_at" && "$resets_at" != "null" ]]; then
                debug_log "Using native JSON fallback for reset info resets_at" "INFO"
            fi
        fi
    fi

    if [[ -z "$resets_at" || "$resets_at" == "null" ]]; then
        # Fallback 2: OAuth API (slower, requires token)
        if declare -f fetch_usage_limits &>/dev/null; then
            local usage_data
            usage_data=$(fetch_usage_limits 2>/dev/null)
            resets_at=$(echo "$usage_data" | jq -r '.five_hour.resets_at // empty' 2>/dev/null)
        fi
    fi

    if [[ -z "$resets_at" || "$resets_at" == "null" ]]; then
        echo ":"
        return 1
    fi

    # Parse resets_at to epoch
    local reset_epoch

    # Detect epoch timestamp (pure digits = Unix epoch seconds from CC v2.1.80+)
    if [[ "$resets_at" =~ ^[0-9]+$ ]]; then
        reset_epoch="$resets_at"
    else
        local normalized_ts
        normalized_ts=$(echo "$resets_at" | sed 's/\.[0-9]*//')

        if [[ "$(uname -s)" == "Darwin" ]]; then
            local mac_ts
            mac_ts=$(echo "$normalized_ts" | sed 's/+00:00/+0000/; s/Z$/+0000/; s/+\([0-9][0-9]\):\([0-9][0-9]\)/+\1\2/')
            reset_epoch=$(date -j -f "%Y-%m-%dT%H:%M:%S%z" "$mac_ts" "+%s" 2>/dev/null)
        else
            reset_epoch=$(date -d "$resets_at" "+%s" 2>/dev/null)
        fi
    fi

    if [[ -z "$reset_epoch" ]]; then
        echo ":"
        return 1
    fi

    # Calculate remaining time
    local now_epoch
    now_epoch=$(date +%s)
    local remaining_seconds=$((reset_epoch - now_epoch))
    local remaining_minutes=$((remaining_seconds / 60))

    # Handle negative (already reset)
    if [[ "$remaining_minutes" -lt 0 ]]; then
        remaining_minutes=0
    fi

    # Format reset time in local timezone (HH.MM format)
    local reset_time_local
    if [[ "$(uname -s)" == "Darwin" ]]; then
        reset_time_local=$(date -r "$reset_epoch" "+%H.%M" 2>/dev/null)
    else
        reset_time_local=$(date -d "@$reset_epoch" "+%H.%M" 2>/dev/null)
    fi

    debug_log "Native reset info: ${reset_time_local}, ${remaining_minutes}m remaining" "INFO"
    echo "${reset_time_local}:${remaining_minutes}"
}

# Get cached reset info (30s TTL)
get_cached_native_reset_info() {
    local cache_key="native_reset_info"
    local cached_result
    cached_result=$(get_cached_value "$cache_key" "$API_LIVE_CACHE_TTL" 2>/dev/null)

    if [[ -n "$cached_result" ]]; then
        echo "$cached_result"
        return 0
    fi

    local result
    result=$(get_native_reset_info)
    set_cached_value "$cache_key" "$result" 2>/dev/null
    echo "$result"
}

# Calculate native block projection
# Returns: projected_cost:projected_tokens
calculate_native_block_projection() {
    # Get current window data
    local burn_rate_data
    burn_rate_data=$(get_cached_native_burn_rate)
    local tokens_per_minute cost_per_hour
    IFS=':' read -r tokens_per_minute cost_per_hour <<< "$burn_rate_data"

    # Get remaining time
    local reset_info
    reset_info=$(get_cached_native_reset_info)
    local remaining_minutes
    remaining_minutes=$(echo "$reset_info" | cut -d: -f2)
    remaining_minutes="${remaining_minutes:-0}"

    # Get current cost
    local current_cost
    current_cost=$(get_api_synced_live_cost)
    current_cost="${current_cost:-0.00}"

    # Get current tokens
    local token_data
    token_data=$(get_cached_window_tokens)
    local current_tokens
    current_tokens=$(echo "$token_data" | cut -d: -f1)
    current_tokens="${current_tokens:-0}"

    # Project to end of window
    local projected_tokens projected_cost
    projected_tokens=$((current_tokens + (tokens_per_minute * remaining_minutes)))

    projected_cost=$(awk -v curr="$current_cost" -v rate="$cost_per_hour" -v mins="$remaining_minutes" \
        'BEGIN { printf "%.2f", curr + (rate * mins / 60) }' 2>/dev/null)

    debug_log "Block projection: \$${projected_cost}, ${projected_tokens} tokens" "INFO"
    echo "${projected_cost}:${projected_tokens}"
}

# Get cached block projection (30s TTL)
get_cached_native_block_projection() {
    local cache_key="native_block_projection"
    local cached_result
    cached_result=$(get_cached_value "$cache_key" "$API_LIVE_CACHE_TTL" 2>/dev/null)

    if [[ -n "$cached_result" ]]; then
        echo "$cached_result"
        return 0
    fi

    local result
    result=$(calculate_native_block_projection)
    set_cached_value "$cache_key" "$result" 2>/dev/null
    echo "$result"
}

# ============================================================================
# EXPORTS
# ============================================================================

export -f format_tokens_compact
export -f get_claude_projects_dir calculate_entry_cost
export -f get_api_window_start calculate_api_synced_live get_api_synced_live_cost
export -f calculate_window_tokens get_cached_window_tokens
export -f calculate_native_burn_rate get_cached_native_burn_rate
export -f get_native_reset_info get_cached_native_reset_info
export -f calculate_native_block_projection get_cached_native_block_projection

debug_log "API-synced LIVE cost module loaded" "INFO"
