#!/bin/bash
set -euo pipefail

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"

source "$SCRIPT_DIR/kugetsu-config.sh"
source "$SCRIPT_DIR/kugetsu-index.sh"
source "$SCRIPT_DIR/kugetsu-worktree.sh"
source "$SCRIPT_DIR/kugetsu-log.sh"

load_agent_env "pm-agent"

acquire_lock() {
    local issue_ref="$1"
    local lock_file="$QUEUE_DIR/locks/$(echo "$issue_ref" | sed 's/[\/:]/-/g' | sed 's/#/-/').lock"
    mkdir -p "$(dirname "$lock_file")"
    if [ -f "$lock_file" ]; then
        local pid=$(cat "$lock_file" 2>/dev/null || echo "")
        if [ -n "$pid" ] && kill -0 "$pid" 2>/dev/null; then
            return 1
        fi
        rm -f "$lock_file"
    fi
    echo $$ > "$lock_file"
    return 0
}

release_lock() {
    local issue_ref="$1"
    local lock_file="$QUEUE_DIR/locks/$(echo "$issue_ref" | sed 's/[\/:]/-/g' | sed 's/#/-/').lock"
    rm -f "$lock_file"
}

check_task_completion() {
    local item="$1"
    local queue_id=$(basename "$item" .json)
    local state=$(python3 -c "import json; print(json.load(open('$item')).get('state', ''))" 2>/dev/null)

    [ "$state" = "notified" ] || return 0

    local session_id=$(python3 -c "import json; print(json.load(open('$item')).get('opencode_session_id', ''))" 2>/dev/null)
    local issue_ref=$(python3 -c "import json; print(json.load(open('$item')).get('issue_ref', ''))" 2>/dev/null)
    local pid=$(python3 -c "import json; print(json.load(open('$item')).get('pid', ''))" 2>/dev/null)
    local notified_at=$(python3 -c "import json; print(json.load(open('$item')).get('notified_at', ''))" 2>/dev/null)

    local timed_out=false
    if [ -n "$notified_at" ]; then
        local notified_epoch=$(date -d "$notified_at" +%s 2>/dev/null || echo "0")
        local now_epoch=$(date +%s)
        local hours_elapsed=$(( (now_epoch - notified_epoch) / 3600 ))
        if [ "$hours_elapsed" -ge "${TASK_TIMEOUT_HOURS:-1}" ]; then
            timed_out=true
            log_warn "queue-daemon" "Task $queue_id ($issue_ref) timed out after ${hours_elapsed}h"
        fi
    fi

    if [ "$timed_out" = true ]; then
        if [ -n "$pid" ] && [ "$pid" != "None" ]; then
            kill "$pid" 2>/dev/null || true
        fi
        if [ -n "$session_id" ]; then
            opencode session stop "$session_id" 2>/dev/null || true
        fi
        update_queue_item_state "$queue_id" "error"
        log_error "queue-daemon" "Task $queue_id ($issue_ref) marked error — timeout after ${hours_elapsed}h"
        release_lock "$issue_ref"
        return
    fi

    if [ -n "$pid" ] && [ "$pid" != "None" ]; then
        if ! kill -0 "$pid" 2>/dev/null; then
            local worktree_path=$(issue_ref_to_worktree_path "$issue_ref" "$WORKTREES_DIR")
            local has_commits=false

            if [ -d "$worktree_path" ] && [ -d "$worktree_path/.git" ]; then
                if [ -n "$(git -C "$worktree_path" log --oneline origin/main..HEAD 2>/dev/null)" ]; then
                    has_commits=true
                fi
            fi

            if [ "$has_commits" = true ]; then
                update_queue_item_state "$queue_id" "completed"
                echo "Task $queue_id ($issue_ref) completed — new commits found"
            else
                update_queue_item_state "$queue_id" "error"
                echo "Task $queue_id ($issue_ref) marked error — no commits found after session ended"
            fi
            release_lock "$issue_ref"
        fi
    else
        if [ -n "$session_id" ] && ! opencode session list 2>/dev/null | grep -q "$session_id"; then
            local worktree_path=$(issue_ref_to_worktree_path "$issue_ref" "$WORKTREES_DIR")
            local has_commits=false

            if [ -d "$worktree_path" ] && [ -d "$worktree_path/.git" ]; then
                if [ -n "$(git -C "$worktree_path" log --oneline origin/main..HEAD 2>/dev/null)" ]; then
                    has_commits=true
                fi
            fi

            if [ "$has_commits" = true ]; then
                update_queue_item_state "$queue_id" "completed"
                echo "Task $queue_id ($issue_ref) completed — new commits found"
            else
                update_queue_item_state "$queue_id" "error"
                echo "Task $queue_id ($issue_ref) marked error — no commits found after session ended"
            fi
            release_lock "$issue_ref"
        fi
    fi
}

get_session_id_for_issue() {
    local issue_ref="$1"
    local session_file=$(issue_ref_to_filename "$issue_ref")
    local session_path="$SESSIONS_DIR/$session_file"
    if [ -f "$session_path" ]; then
        python3 -c "import json; print(json.load(open('$session_path')).get('opencode_session_id', ''))" 2>/dev/null || echo ""
    else
        echo ""
    fi
}

process_task() {
    local item="$1"
    local queue_id=$(basename "$item" .json)
    local issue_ref=$(python3 -c "import json; print(json.load(open('$item')).get('issue_ref', ''))" 2>/dev/null)
    local message=$(python3 -c "import json; print(json.load(open('$item')).get('message', ''))" 2>/dev/null)

    if ! acquire_lock "$issue_ref"; then
        echo "Task $queue_id ($issue_ref) skipped — another process is handling it"
        return
    fi

    source "$SCRIPT_DIR/kugetsu-session.sh"

    log_file="$LOGS_DIR/delegate-$(date +%s).log"
    if cmd_continue "$issue_ref" "$message" >> "$log_file" 2>&1; then
        sleep 1
        local session_id=$(get_session_id_for_issue "$issue_ref")
        update_queue_item_state "$queue_id" "notified" "$session_id" ""
        echo "Task $queue_id continued for $issue_ref"
    else
        update_queue_item_state "$queue_id" "error"
        echo "Task $queue_id ($issue_ref) failed to continue"
    fi

    release_lock "$issue_ref"
}

while true; do
    if [ -d "$QUEUE_ITEMS_DIR" ]; then
        for item in "$QUEUE_ITEMS_DIR"/*.json; do
            [ -f "$item" ] || continue
            check_task_completion "$item"
        done

        for item in "$QUEUE_ITEMS_DIR"/*.json; do
            [ -f "$item" ] || continue
            state=$(python3 -c "import json; print(json.load(open('$item')).get('state', ''))" 2>/dev/null)
            if [ "$state" = "pending" ]; then
                process_task "$item"
            fi
        done
    fi
    sleep "${QUEUE_DAEMON_INTERVAL_MINUTES:-5}m"
done